[
{
"id": "https://authors.library.caltech.edu/records/z63xj-vka05",
"eprint_status": "archive",
"datestamp": "2026-06-13 18:42:51",
"lastmod": "2026-06-13 18:42:51",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Audard",
"given": "Marc"
},
"orcid": "0000-0003-4721-034X"
},
{
"name": {
"family": "Awaki",
"given": "Hisamitsu"
}
},
{
"name": {
"family": "Ballhausen",
"given": "Ralf"
},
"orcid": "0000-0002-1118-8470"
},
{
"name": {
"family": "Bamba",
"given": "Aya"
},
"orcid": "0000-0003-0890-4920"
},
{
"name": {
"family": "Behar",
"given": "Ehud"
},
"orcid": "0000-0001-9735-4873"
},
{
"name": {
"family": "Boissay-Malaquin",
"given": "Rozenn"
},
"orcid": "0000-0003-2704-599X"
},
{
"name": {
"family": "Brenneman",
"given": "Laura"
},
"orcid": "0000-0003-2663-1954"
},
{
"name": {
"family": "Brown",
"given": "Gregory V."
},
"orcid": "0000-0001-6338-9445"
},
{
"name": {
"family": "Corcoran",
"given": "Michael F."
},
"orcid": "0000-0002-7762-3172"
},
{
"name": {
"family": "Corrales",
"given": "Lia"
},
"orcid": "0000-0002-5466-3817"
},
{
"name": {
"family": "Costantini",
"given": "Elisa"
},
"orcid": "0000-0001-8470-749X"
},
{
"name": {
"family": "Cumbee",
"given": "Renata"
},
"orcid": "0000-0001-9894-295X"
},
{
"name": {
"family": "Diaz Trigo",
"given": "Maria"
},
"orcid": "0000-0001-7796-4279"
},
{
"name": {
"family": "Done",
"given": "Chris"
},
"orcid": "0000-0002-1065-7239"
},
{
"name": {
"family": "Dotani",
"given": "Tadayasu"
}
},
{
"name": {
"family": "Ebisawa",
"given": "Ken"
},
"orcid": "0000-0002-5352-7178"
},
{
"name": {
"family": "Eckart",
"given": "Megan E."
},
"orcid": "0000-0003-3894-5889"
},
{
"name": {
"family": "Eckert",
"given": "Dominique"
},
"orcid": "0000-0001-7917-3892"
},
{
"name": {
"family": "Eguchi",
"given": "Satoshi"
},
"orcid": "0000-0003-2814-9336"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Ezoe",
"given": "Yuichiro"
}
},
{
"name": {
"family": "Foster",
"given": "Adam"
},
"orcid": "0000-0003-3462-8886"
},
{
"name": {
"family": "Fujimoto",
"given": "Ryuichi"
},
"orcid": "0000-0002-2374-7073"
},
{
"name": {
"family": "Fujita",
"given": "Yutaka"
},
"orcid": "0000-0003-0058-9719"
},
{
"name": {
"family": "Fukazawa",
"given": "Yasushi"
},
"orcid": "0000-0002-0921-8837"
},
{
"name": {
"family": "Fukushima",
"given": "Kotaro"
},
"orcid": "0000-0001-8055-7113"
},
{
"name": {
"family": "Furuzawa",
"given": "Akihiro"
}
},
{
"name": {
"family": "Gallo",
"given": "Luigi"
},
"orcid": "0009-0006-4968-7108"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Goto",
"given": "Emi"
}
},
{
"name": {
"family": "Gu",
"given": "Liyi"
},
"orcid": "0000-0001-9911-7038"
},
{
"name": {
"family": "Guainazzi",
"given": "Matteo"
},
"orcid": "0000-0002-1094-3147"
},
{
"name": {
"family": "Hagino",
"given": "Kouichi"
},
"orcid": "0000-0003-4235-5304"
},
{
"name": {
"family": "Hamaguchi",
"given": "Kenji"
},
"orcid": "0000-0001-7515-2779"
},
{
"name": {
"family": "Hatsukade",
"given": "Isamu"
},
"orcid": "0000-0003-3518-3049"
},
{
"name": {
"family": "Hayashi",
"given": "Katsuhiro"
},
"orcid": "0000-0001-6922-6583"
},
{
"name": {
"family": "Hayashi",
"given": "Takayuki"
},
"orcid": "0000-0001-6665-2499"
},
{
"name": {
"family": "Hell",
"given": "Natalie"
},
"orcid": "0000-0003-3057-1536"
},
{
"name": {
"family": "Hodges-Kluck",
"given": "Edmund"
},
"orcid": "0000-0002-2397-206X"
},
{
"name": {
"family": "Hornschemeier",
"given": "Ann"
},
"orcid": "0000-0001-8667-2681"
},
{
"name": {
"family": "Ichinohe",
"given": "Yuto"
},
"orcid": "0000-0002-6102-1441"
},
{
"name": {
"family": "Inoue",
"given": "Shun"
}
},
{
"name": {
"family": "Ishi",
"given": "Daiki"
}
},
{
"name": {
"family": "Ishida",
"given": "Manabu"
}
},
{
"name": {
"family": "Ishihara",
"given": "Yukiko"
}
},
{
"name": {
"family": "Ishikawa",
"given": "Kumi"
}
},
{
"name": {
"family": "Ishisaki",
"given": "Yoshitaka"
}
},
{
"name": {
"family": "Junqueira",
"given": "Francisco"
}
},
{
"name": {
"family": "Kaastra",
"given": "Jelle"
},
"orcid": "0000-0001-5540-2822"
},
{
"name": {
"family": "Kallman",
"given": "Timothy"
}
},
{
"name": {
"family": "Kanemaru",
"given": "Yoshiaki"
},
"orcid": "0000-0002-4541-1044"
},
{
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"name": {
"family": "Katsuda",
"given": "Satoru"
},
"orcid": "0000-0002-1104-7205"
},
{
"name": {
"family": "Kelley",
"given": "Richard L."
},
"orcid": "0009-0007-2283-3336"
},
{
"name": {
"family": "Kilbourne",
"given": "Caroline A."
},
"orcid": "0000-0001-9464-4103"
},
{
"name": {
"family": "Kitamoto",
"given": "Shunji"
},
"orcid": "0000-0001-8948-7983"
},
{
"name": {
"family": "Kobayashi",
"given": "Shogo"
},
"orcid": "0000-0001-7773-9266"
},
{
"name": {
"family": "Kohmura",
"given": "Takayoshi"
}
},
{
"name": {
"family": "Kubota",
"given": "Aya"
}
},
{
"name": {
"family": "Leutenegger",
"given": "Maurice"
},
"orcid": "0000-0002-3331-7595"
},
{
"name": {
"family": "Loewenstein",
"given": "Michael"
},
"orcid": "0000-0002-1661-4029"
},
{
"name": {
"family": "Maeda",
"given": "Yoshitomo"
},
"orcid": "0000-0002-9099-5755"
},
{
"name": {
"family": "Markevitch",
"given": "Maxim"
},
"orcid": "0000-0003-0144-4052"
},
{
"name": {
"family": "Matsumoto",
"given": "Hironori"
}
},
{
"name": {
"family": "Matsushita",
"given": "Kyoko"
},
"orcid": "0000-0003-2907-0902"
},
{
"name": {
"family": "McCammon",
"given": "Dan"
},
"orcid": "0000-0001-5170-4567"
},
{
"name": {
"family": "McNamara",
"given": "Brian"
}
},
{
"name": {
"family": "Mernier",
"given": "Fran\u00e7ois"
},
"orcid": "0000-0002-7031-4772"
},
{
"name": {
"family": "Vander Meulen",
"given": "Bert"
},
"orcid": "0000-0002-5488-1961"
},
{
"name": {
"family": "Miller",
"given": "Eric D."
},
"orcid": "0000-0002-3031-2326"
},
{
"name": {
"family": "Miller",
"given": "Jon M."
},
"orcid": "0000-0003-2869-7682"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Miyamoto",
"given": "Asca"
}
},
{
"name": {
"family": "Mizumoto",
"given": "Misaki"
},
"orcid": "0000-0003-2161-0361"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Mori",
"given": "Koji"
},
"orcid": "0000-0002-0018-0369"
},
{
"name": {
"family": "Mukai",
"given": "Koji"
},
"orcid": "0000-0002-8286-8094"
},
{
"name": {
"family": "Murakami",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Nakajima",
"given": "Hiroshi"
},
"orcid": "0000-0001-6988-3938"
},
{
"name": {
"family": "Nakazawa",
"given": "Kazuhiro"
},
"orcid": "0000-0003-2930-350X"
},
{
"name": {
"family": "Ness",
"given": "Jan-Uwe"
}
},
{
"name": {
"family": "Nobukawa",
"given": "Kumiko"
},
"orcid": "0000-0002-0726-7862"
},
{
"name": {
"family": "Nobukawa",
"given": "Masayoshi"
},
"orcid": "0000-0003-1130-5363"
},
{
"name": {
"family": "Noda",
"given": "Hirofumi"
},
"orcid": "0000-0001-6020-517X"
},
{
"name": {
"family": "Odaka",
"given": "Hirokazu"
}
},
{
"name": {
"family": "Ogawa",
"given": "Shoji"
},
"orcid": "0000-0002-5701-0811"
},
{
"name": {
"family": "Ogorza\u0142ek",
"given": "Anna"
},
"orcid": "0000-0003-4504-2557"
},
{
"name": {
"family": "Okajima",
"given": "Takashi"
},
"orcid": "0000-0002-6054-3432"
},
{
"name": {
"family": "Ota",
"given": "Naomi"
},
"orcid": "0000-0002-2784-3652"
},
{
"name": {
"family": "Paltani",
"given": "Stephane"
},
"orcid": "0000-0002-8108-9179"
},
{
"name": {
"family": "Petre",
"given": "Robert"
},
"orcid": "0000-0003-3850-2041"
},
{
"name": {
"family": "Plucinsky",
"given": "Paul"
},
"orcid": "0000-0003-1415-5823"
},
{
"name": {
"family": "Porter",
"given": "Frederick S."
},
"orcid": "0000-0002-6374-1119"
},
{
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
},
{
"name": {
"family": "Sato",
"given": "Kosuke"
}
},
{
"name": {
"family": "Sato",
"given": "Toshiki"
}
},
{
"name": {
"family": "Sawada",
"given": "Makoto"
},
"orcid": "0000-0003-2008-6887"
},
{
"name": {
"family": "Seta",
"given": "Hiromi"
}
},
{
"name": {
"family": "Shidatsu",
"given": "Megumi"
},
"orcid": "0000-0001-8195-6546"
},
{
"name": {
"family": "Simionescu",
"given": "Aurora"
},
"orcid": "0000-0002-9714-3862"
},
{
"name": {
"family": "Smith",
"given": "Randall"
},
"orcid": "0000-0003-4284-4167"
},
{
"name": {
"family": "Suzuki",
"given": "Hiromasa"
},
"orcid": "0000-0002-8152-6172"
},
{
"name": {
"family": "Szymkowiak",
"given": "Andrew"
},
"orcid": "0000-0002-4974-687X"
},
{
"name": {
"family": "Takahashi",
"given": "Hiromitsu"
},
"orcid": "0000-0001-6314-5897"
},
{
"name": {
"family": "Takeo",
"given": "Mai"
}
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
}
},
{
"name": {
"family": "Tamura",
"given": "Keisuke"
}
},
{
"name": {
"family": "Tanaka",
"given": "Takaaki"
},
"orcid": "0000-0002-4383-0368"
},
{
"name": {
"family": "Tanimoto",
"given": "Atsushi"
},
"orcid": "0000-0002-0114-5581"
},
{
"name": {
"family": "Tashiro",
"given": "Makoto"
},
"orcid": "0000-0002-5097-1257"
},
{
"name": {
"family": "Terada",
"given": "Yukikatsu"
},
"orcid": "0000-0002-2359-1857"
},
{
"name": {
"family": "Terashima",
"given": "Yuichi"
},
"orcid": "0000-0003-1780-5481"
},
{
"name": {
"family": "Tsuboi",
"given": "Yohko"
},
"orcid": "0000-0001-9943-0024"
},
{
"name": {
"family": "Tsujimoto",
"given": "Masahiro"
},
"orcid": "0000-0002-9184-5556"
},
{
"name": {
"family": "Tsunemi",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Tsuru",
"given": "Takeshi"
},
"orcid": "0000-0002-5504-4903"
},
{
"name": {
"family": "T\u00fcmer",
"given": "Ay\u015feg\u00fcl"
},
"orcid": "0000-0002-3132-8776"
},
{
"name": {
"family": "Uchida",
"given": "Hiroyuki"
},
"orcid": "0000-0003-1518-2188"
},
{
"name": {
"family": "Uchida",
"given": "Nagomi"
},
"orcid": "0000-0002-5641-745X"
},
{
"name": {
"family": "Uchida",
"given": "Yuusuke"
},
"orcid": "0000-0002-7962-4136"
},
{
"name": {
"family": "Uchiyama",
"given": "Hideki"
},
"orcid": "0000-0003-4580-4021"
},
{
"name": {
"family": "Ueda",
"given": "Shutaro"
},
"orcid": "0000-0001-6252-7922"
},
{
"name": {
"family": "Ueda",
"given": "Yoshihiro"
},
"orcid": "0000-0001-7821-6715"
},
{
"name": {
"family": "Uno",
"given": "Shinichiro"
}
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Watanabe",
"given": "Shin"
},
"orcid": "0000-0003-0441-7404"
},
{
"name": {
"family": "Williams",
"given": "Brian J."
},
"orcid": "0000-0003-2063-381X"
},
{
"name": {
"family": "Yamada",
"given": "Satoshi"
},
"orcid": "0000-0002-9754-3081"
},
{
"name": {
"family": "Yamada",
"given": "Shinya"
},
"orcid": "0000-0003-4808-893X"
},
{
"name": {
"family": "Yamaguchi",
"given": "Hiroya"
},
"orcid": "0000-0002-5092-6085"
},
{
"name": {
"family": "Yamaoka",
"given": "Kazutaka"
},
"orcid": "0000-0003-3841-0980"
},
{
"name": {
"family": "Yamasaki",
"given": "Noriko"
},
"orcid": "0000-0003-4885-5537"
},
{
"name": {
"family": "Yamauchi",
"given": "Makoto"
},
"orcid": "0000-0003-1100-1423"
},
{
"name": {
"family": "Yamauchi",
"given": "Shigeo"
}
},
{
"name": {
"family": "Yaqoob",
"given": "Tahir"
}
},
{
"name": {
"family": "Yoneyama",
"given": "Tomokage"
}
},
{
"name": {
"family": "Yoshida",
"given": "Tessei"
}
},
{
"name": {
"family": "Yukita",
"given": "Mihoko"
},
"orcid": "0000-0001-6366-3459"
},
{
"name": {
"family": "Zhuravleva",
"given": "Irina"
},
"orcid": "0000-0001-7630-8085"
}
]
},
"title": "High-spectral-resolution X-Ray Observations of the Evolved Supermassive Stellar Binary System \u03b7 Carinae: Fe K\u03b1 Band Profile Revealed with XRISM",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Stellar abundances; Luminous blue variable stars; Massive stars; Binary stars; Stellar winds",
"note": "© 2026. The Author(s). Published by the American Astronomical Society.
\n\nWe appreciate fruitful discussions with Drs. Augusto Damineli, Theodor R. Gull, D. John Hillier, Jonathan Mackey, Anthony F.J., Moffat, Yaël Nazé, Julian M. Pittard, Noel Richardson, Christopher Russell, and Gerd Weigelt. The material is based upon work supported by NASA under award Nos. 80GSFC21M0002, 80GSFC24M0006, 80NSSC18K1684, 80NSSC18K0988, 80NSSC20K0733, 80NSSC20K0737, 80NSSC20K0883, 80NNSC22K1922, 80NSSC23K1656, 80NSSC24K0678, 80NSSC24K1148, 80NSSC24K1774, 80NSSC25K7064, and 80NSSC25K7536, and contract NAS8-0360. This work is supported by JSPS KAKENHI grant Nos. JP19K14762, JP19K21884, JP20H00157, JP20H01946, JP20H01947, JP20H05857, JP20K04009, JP20K14491, JP20KK0071, JP21H01095, JP21H04493, JP21K03615, JP21K13958, JP21K13963, JP22H00158, JP23H00121, JP23H00151, JP23H01211, JP23K03454, JP23K03459, JP23H04899, JP23K13154, JP23K20239, JP23K20850, JP23K22548, JP23KJ1807, JP24H00253, JP24K00638, JP24K00672, JP24K00677, JP24K17093, JP24K17104, JP24K17105, JP25H00672, and JP25K01026. This work is supported by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, STFC through grant ST/T000244/1, Canadian Space Agency grant 18XARMSTMA, the Alfred P. Sloan Foundation through the Sloan Research Fellowship, the Israel Science Foundation grant 2617/25, the JSPS Core-to-Core Program, JPJSCCA20220002, the RIKEN Pioneering Project Evolution of Matter in the Universe (r-EMU), the RIKEN SPDR Program, Rikkyo University Special Fund for Research (Rikkyo SFR), the Kagoshima University postdoctoral research program (KU-DREAM), the Strategic Research Center of Saitama University, Program for Forming Japan’s Peak Research Universities (J-PEAKS), and the Organization for the Promotion of Gender Equality at Nara Women's University.
\n\nXRISM - (Resolve, Xtend).
\n\nHEASoft (Nasa High Energy Astrophysics Science Archive Research Center (Heasarc) 2014), xspec (K. A. Arnaud 1996), scipy (P. Virtanen et al. 2020), astropy (Astropy Collaboration et al. 2013), AtomDB ver. 3.1.2 (A. R. Foster et al. 2012).
",
"abstract": "\n
The supermassive binary system, η Carinae, is experiencing enormous wind-driven mass loss at a rate unparalleled in the rest of the Galaxy. Their wind–wind collision (WWC) continuously produces shock heated, X-ray-emitting plasmas. The XRISM X-ray observatory observed the system in 2023 and 2024 when the X-ray emission began to increase toward periastron passage in 2025. This paper reports unprecedentedly high-resolution X-ray spectra in the Fe Kα band between 6.2 and 7.1 keV, obtained with the Resolve X-ray microcalorimeter. The hydrogen-like (Lyα) and helium-like (Heα) lines reveal three velocity components. Two of them are broadened with maximum velocities of 2000–3000 km s−1, likely originating from the postshock companion wind. The other is relatively narrow, with a Gaussian broadening of only ∼290 km s−1 in 1σ, which may originate from the postshock companion wind at the WWC stagnation point or penetrating the primary wind. The Fe fluorescent lines exhibit a moderate blueshift and broadening with velocities at 100–200 km s−1, consistent with the primary wind’s velocity field. The spectra also confirm a Compton shoulder of the Heα line complex for the first time. Both fluorescing and scattering spectral profiles indicate that the binary system is seen from the companion side during these observations. The flux ratio of the Compton-scattering emission to the fluorescent line suggests substantial hydrogen depletion of the primary wind, expected from CNO-cycled hydrogen nuclear fusion gas.
\n
© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
We thank the anonymous referee for comments that improved this manuscript. J.M.M. acknowledges helpful conversations with Niel Brandt and Michael Eracleous, and SPEX help from Jelle de Plaa.
\n
\n
NGC 4151 is the brightest Seyfert 1 galaxy in the band of the Resolve calorimeter aboard XRISM. It has been observed on 14 occasions. Herein, we report on an analysis of its time-averaged 893 ks spectrum. The narrow Fe K α emission-line complex requires contributions from the torus and optical broad-line region (BLR). Models assuming an emissivity index of q = 2 for these components are statistically preferred, consistent with a \"bowl\" geometry for the central engine. A smooth red wing of these line components is consistent with Compton scattering from bound electrons, signaling the presence of dust in the base of the BLR and in the torus. The data statistically prefer relativistic reflection from a disk with an inner radius of r = 3.2(−2.0)^(+3.5) GM/c², and an inclination of θ = 29.7_(−0.4)^(+0.5) degrees. The Fe K edge at 7.1 keV is best modeled with contributions from multiple charge states, consistent with cool, kT \u2243 5 eV collisional gas or photoionized gas. Slow \"warm absorber\" winds spanning Fe XX–XXVI , faster winds seen via Fe XXV and Fe XXVI lines, and ultra-fast outflows (UFOs) are detected simultaneously. The warm absorbers are \"failed\" winds; the data constrain their radius, density, filling factor, and distribution. For the most conservative volume filling factors, the UFOs may not be able to halt star formation. However, the UFOs may generate galaxy-altering feedback for larger filling factors and/or during certain intervals.
",
"date": "2026-06-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "1003",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "L34",
"issn": "2041-8205",
"official_url": "https://authors.library.caltech.edu/records/pvgqe-5qf85",
"funders": {
"items": [
{
"agency": "NASA/GSFC",
"grant_number": "F071940"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/ae63cd",
"primary_object": {
"basename": "Miller_2026_ApJL_1003_L34.pdf",
"url": "https://authors.library.caltech.edu/records/pvgqe-5qf85/files/Miller_2026_ApJL_1003_L34.pdf"
},
"pub_year": "2026",
"author_list": "Miller, Jon M.; Xiang, Xin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gnd2y-jk125",
"eprint_status": "archive",
"datestamp": "2026-06-04 18:42:15",
"lastmod": "2026-06-04 18:42:15",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Raouafi",
"given": "N. E."
}
},
{
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"name": {
"family": "Kouloumvakos",
"given": "A."
},
"orcid": "0000-0001-6589-4509"
},
{
"name": {
"family": "Collier",
"given": "H."
}
},
{
"name": {
"family": "Roelof",
"given": "E. C."
}
},
{
"name": {
"family": "Berland",
"given": "G."
},
"orcid": "0000-0001-6010-6374"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Mostafavi",
"given": "P. S."
},
"orcid": "0000-0002-3808-3580"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Whittlesey",
"given": "P. L."
},
"orcid": "0000-0002-7287-5098"
}
]
},
"title": "The 3He-rich SEP on Event 2024 April 1 at 27 Solar Radii\u2014Indications of Acceleration by Waves and Implications of Coronal Source Location",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar particle emission; Solar active region magnetic fields",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nParker Solar Probe was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission.
\nThis work was supported by the IS\u2609IS instrument suite on NASA’s Parker Solar Probe Mission, contract NNN06AA01C. The data supporting the analysis of the energetic-particle event was measured largely by the EPI-Lo instrument of the IS\u2609IS instrument suite. P.M. acknowledges the support from NASA HGIO grant No. 80NSSC23K0419. G.M.M. also acknowledges support under NASA contract NNN06AA01C. D.L. acknowledges support from the Strategic Capability project under NASA grant No. 80NSSC22K0892 (SCEPTER).
",
"abstract": "\n
Parker Solar Probe (PSP) observations of a small dispersive event on 2024 April 1 reveal highly enriched 3He abundance in the suprathermal energy range (40–250 keV nucleon−1). Time dispersion observed in this impulsive solar energetic particle (SEP) event is consistent with an estimated onset time of 22:50 UT on 2024 March 31. The event occurred during an orbital segment as PSP moved from about 27 Rs to about 29 Rs while outbound in orbit 19. For this segment of the orbit, PSP’s motion in Carrington coordinates remains within about 1° of the same Carrington longitude. The 3He content is much larger than the usual SEP abundances, especially in this energy range. Additionally, the 3He energy spectrum is not power law in shape, unlike the H and 4He spectra. Heavy ions (O, Fe) are also somewhat enhanced. These compositional signatures suggest that this is an example of resonant wave–particle acceleration, as hypothesized for generating the suprathermal seed particles required to account for the enrichment of various species above solar abundances in shock (or compression) acceleration models of SEP events. Like many previously reported impulsive 3He-rich events, this event is associated with an energetic electron beam, type III radio emission, and a hard X-ray flare. However, associating the hard X-ray event with this SEP event requires significant (∼60°) prompt longitudinal propagation of energetic particles in the low corona before they access open magnetic flux, complicating its interpretation as part of the source process for this particular event.
\n
© The Author(s) 2026. Published by Oxford University Press on behalf of the Astronomical Society of Japan.
\n\n
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
\n
The XRISM observation provided new findings and further motivated our interest. This work was made possible by the dedicated efforts of the XRISM team members, engineers, and operations team, and we thank them for their efforts. The NuSTAR observation enhanced the scientific value of the XRISM data, and we also thank all members of the NuSTAR mission. Additionally, we thank the referee for their helpful comments and Yoshiyuki Inoue for valuable discussions.
\n\nTK, RT, KO, HN, and HM are supported by JSPS KAKENHI grant numbers 23K13153/24K00673, 24KJ0152, 22H00128/22K18277, 23K20239/24K00672/25H00660, and 23H00128, respectively. SB acknowledges funding from PRIN MUR 2022 SEAWIND 2022Y2T94C, supported by European Union - Next Generation EU, Mission 4 Component 1 CUP C53D23001330006. CR acknowledges support from SNSF Consolidator grant F01-13252, Fondecyt Regular grant 1230345, ANID BASAL project FB210003 and the China–Chile joint research fund. This work was supported by JSPS Core-to-Core Program, (grant number: JPJSCCA20220002).
",
"abstract": "We present an analysis of XRISM and NuSTAR data obtained for the nearby low-Eddington active galactic nucleus NGC 7213. Our goal is to examine whether its He-like and H-like iron emission lines can be reproduced by photoionization or collisional ionization processes. Using the broad-band energy coverage of our data (2–60 keV), we first constrained the continuum shape. Then, we focused on the iron-K band in the Resolve spectrum. Gaussian fits to Fe xxv He$\\alpha$ and Fe xxvi Ly$\\alpha$ lines suggest that they may have different velocity widths: $v_\\sigma =790^{+370}_{-240}$ km s$^{-1}$ for Fe xxv and $v_\\sigma =2610^{+1700}_{-1580}$ km s$^{-1}$ for Fe xxvi. In this case, the He$\\alpha$ resonance line (w) and forbidden line (z) have similar intensities of ${\\approx }0.5$–$0.6\\times 10^{-5}$ ph s$^{-1}$ cm$^{-2}$, while the intercombination lines (x + y) are not significantly detected with upper limits of ${\\lesssim }0.2\\times 10^{-5}$ ph s$^{-1}$ cm$^{-2}$. Motivated by the possible difference in the line widths, we tested one- and two-zone photoionized and collisionally ionized models. Our results show that the additional ionized component is not significantly required, and the current data cannot uniquely determine whether photoionization or collisional ionization dominates. Moreover, if the Fe xxv He$\\alpha$ complex implies that the weak x + y lines are suppressed relative to the w and z lines, such a structure is difficult to reproduce with either ionization model adopted. Finally, by comparing NGC 7213 with M 81$^\\ast$, accreting at a much lower Eddington ratio of $\\lambda _{\\rm Edd}\\sim 10^{-5}$, we found a decrease in the density of the gas responsible for highly ionized iron emission, which may imply that the density decreases with decreasing $\\lambda _{\\rm Edd}$.
",
"date": "2026-06",
"date_type": "published",
"publication": "Publications of the Astronomical Society of Japan",
"volume": "78",
"number": "3",
"publisher": "Oxford University Press (OUP)",
"pagerange": "1130-1140",
"issn": "0004-6264",
"official_url": "https://authors.library.caltech.edu/records/j7kxx-th939",
"funders": {
"items": [
{
"grant_number": "23K13153"
},
{
"grant_number": "24K00673"
},
{
"grant_number": "24KJ0152"
},
{
"grant_number": "22H00128"
},
{
"grant_number": "22K18277"
},
{
"grant_number": "23K20239"
},
{
"grant_number": "24K00672"
},
{
"grant_number": "25H00660"
},
{
"grant_number": "23H00128"
},
{
"agency": "PRIN"
},
{
"agency": "MUR",
"grant_number": "2022Y2T94C"
},
{
"grant_number": "C53D23001330006"
},
{
"grant_number": "F01-13252"
},
{
"grant_number": "1230345"
},
{
"grant_number": "FB210003"
},
{
"grant_number": "JPJSCCA20220002"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1093/pasj/psag049",
"primary_object": {
"basename": "psag049.pdf",
"url": "https://authors.library.caltech.edu/records/j7kxx-th939/files/psag049.pdf"
},
"pub_year": "2026",
"author_list": "Murakami, Kaito; Kawamuro, Taiki; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2h94d-w9e28",
"eprint_status": "archive",
"datestamp": "2026-05-30 11:59:13",
"lastmod": "2026-05-30 11:59:13",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Yao",
"given": "Yuhan"
},
"orcid": "0000-0001-6747-8509"
},
{
"name": {
"family": "Chornock",
"given": "Ryan"
},
"orcid": "0000-0002-7706-5668"
},
{
"name": {
"family": "Mummery",
"given": "Andrew"
}
},
{
"name": {
"family": "Margutti",
"given": "Raffaella"
},
"orcid": "0000-0003-4768-7586"
},
{
"name": {
"family": "Gilfanov",
"given": "Marat"
}
},
{
"name": {
"family": "Guolo",
"given": "Muryel"
},
"orcid": "0000-0002-5063-0751"
},
{
"name": {
"family": "Coughlin",
"given": "Eric R"
},
"orcid": "0000-0003-3765-6401"
},
{
"name": {
"family": "Lu",
"given": "Wenbin"
},
"orcid": "0000-0002-1568-7461"
},
{
"name": {
"family": "Chakraborty",
"given": "Joheen"
},
"orcid": "0000-0002-0568-6000"
},
{
"name": {
"family": "Pasham",
"given": "Dheeraj R"
},
"orcid": "0000-0003-1386-7861"
},
{
"name": {
"family": "Alexander",
"given": "Kate D"
},
"orcid": "0000-0002-8297-2473"
},
{
"name": {
"family": "Aspegren",
"given": "Olivia"
},
"orcid": "0000-0001-5674-8403"
},
{
"name": {
"family": "Angus",
"given": "Charlotte R"
},
"orcid": "0000-0002-4269-7999"
},
{
"name": {
"family": "Guo",
"given": "Xinze"
},
"orcid": "0009-0002-9727-8326"
},
{
"name": {
"family": "Hall",
"given": "Xander J"
},
"orcid": "0000-0002-9364-5419"
},
{
"name": {
"family": "Hammerstein",
"given": "Erica"
},
"orcid": "0000-0002-5698-8703"
},
{
"name": {
"family": "Hinds",
"given": "K -Ryan"
},
"orcid": "0000-0002-0129-806X"
},
{
"name": {
"family": "Ho",
"given": "Anna Y Q"
},
"orcid": "0000-0002-9017-3567"
},
{
"id": "Huang-Xiaoshan",
"name": {
"family": "Huang",
"given": "Xiaoshan"
},
"orcid": "0000-0003-2868-489X"
},
{
"id": "Kammoun-Elias",
"name": {
"family": "Kammoun",
"given": "Elias"
},
"orcid": "0000-0002-0273-218X"
},
{
"name": {
"family": "LeBaron",
"given": "Natalie"
},
"orcid": "0000-0002-2249-0595"
},
{
"name": {
"family": "Lucchini",
"given": "Matteo"
},
"orcid": "0000-0002-2235-3347"
},
{
"name": {
"family": "McGrath",
"given": "Zo\u00eb"
},
"orcid": "0009-0006-0726-1328"
},
{
"name": {
"family": "Nicholl",
"given": "Matt"
},
"orcid": "0000-0002-2555-3192"
},
{
"name": {
"family": "Perley",
"given": "Daniel A"
},
"orcid": "0000-0001-8472-1996"
},
{
"name": {
"family": "Rich",
"given": "R Michael"
},
"orcid": "0000-0003-0427-8387"
},
{
"name": {
"family": "Schroeder",
"given": "Genevieve"
},
"orcid": "0000-0001-9915-8147"
},
{
"name": {
"family": "Sheng",
"given": "Xinyue"
},
"orcid": "0000-0002-6527-1368"
},
{
"name": {
"family": "Sollerman",
"given": "Jesper"
},
"orcid": "0000-0003-1546-6615"
},
{
"name": {
"family": "Somalwar",
"given": "Jean"
},
"orcid": "0000-0001-8426-5732"
},
{
"name": {
"family": "Wise",
"given": "Jacob L"
},
"orcid": "0000-0003-0733-2916"
},
{
"name": {
"family": "Coughlin",
"given": "Michael W"
},
"orcid": "0000-0002-8262-2924"
},
{
"id": "Drake-Andrew",
"name": {
"family": "Drake",
"given": "Andrew"
},
"orcid": "0000-0003-0228-6594"
},
{
"id": "Graham-M-J",
"name": {
"family": "Graham",
"given": "Matthew J"
},
"orcid": "0000-0002-3168-0139"
},
{
"id": "Helou-G",
"name": {
"family": "Helou",
"given": "George"
},
"orcid": "0000-0003-3367-3415"
},
{
"id": "Jaimes-Joahan-C",
"name": {
"family": "Jaimes",
"given": "Joahan C"
},
"orcid": "0000-0002-0987-3372"
},
{
"id": "Kasliwal-M-M",
"name": {
"family": "Kasliwal",
"given": "Mansi M"
},
"orcid": "0000-0002-5619-4938"
},
{
"id": "Mahabal-A-A",
"name": {
"family": "Mahabal",
"given": "Ashish A"
},
"orcid": "0000-0003-2242-0244"
},
{
"name": {
"family": "Medvedev",
"given": "Pavel"
},
"orcid": "0000-0002-9380-8708"
},
{
"id": "Purdum-Josiah-N",
"name": {
"family": "Purdum",
"given": "Josiah"
},
"orcid": "0000-0003-1227-3738"
},
{
"id": "Rusholme-Benjamin",
"name": {
"family": "Rusholme",
"given": "Ben"
},
"orcid": "0000-0001-7648-4142"
},
{
"name": {
"family": "Sunyaev",
"given": "Rashid"
}
}
]
},
"title": "AT2024lhc and AT2024kmq in the landscape of featureless tidal disruption events",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion; black hole physics; galaxies: nuclei; transients: tidal disruption events",
"note": "© The Author(s) 2026. Published by Oxford University Press on behalf of Royal Astronomical Society.
\n\n
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
\n
YY, RC, and EH acknowledge support from the NASA/NuSTAR GO programme, grant 80NSSC25K7488. AM acknowledges support from the Ambrose Monell Foundation, the W. M. Keck Foundation and the John N. Bahcall Fellowship Fund at the Institute for Advanced Study. MG acknowledges support by the Ministry of Science and Higher Education grant 075-15-2024-647. ERC acknowledges support from the National Aeronautics and Space Administration through the Astrophysics Theory Program, grant 80NSSC24K0897. DRP acknowledges the support of the NASA/NuSTAR GO programme, grant 80NSSC25K7949. KDA gratefully acknowledges support provided by the NSF through award AST-2307668and from the Alfred P. Sloan Foundation. CRA, MN, and XS are supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 948381). MWC acknowledges support from the National Science Foundation with grant numbers PHY-2117997, PHY-2308862, and PHY-2409481.
\nThis work is partly based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Support for Program number GO-17667 was provided through a grant from the STScI under NASA contract NAS5-26555.
\nBased on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant Nos AST-1440341, AST-2034437, and currently Award #2407588. ZTF receives additional funding from the ZTF partnership. Current members include Caltech, USA; Caltech/IPAC, USA; University of Maryland, USA; University of California, Berkeley, USA; University of Wisconsin at Milwaukee, USA; Cornell University, USA; Drexel University, USA; University of North Carolina at Chapel Hill, USA; Institute of Science and Technology, Austria; National Central University, Taiwan, and OKC, University of Stockholm, Sweden. Operations are conducted by Caltech’s Optical Observatory (COO), Caltech/IPAC, and the University of Washington at Seattle, USA.
\nThe Gordon and Betty Moore Foundation, through both the Data-Driven Investigator Program and a dedicated grant, provided critical funding for SkyPortal. The ZTF forced-photometry service was funded under the Heising-Simons Foundation grant No. 12540303(PI: Graham).
\nThe National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.
\nThis work has made use of data from the Asteroid Terrestrial-impact Last Alert System (ATLAS) project. The ATLAS project is primarily funded to search for near earth asteroids through NASA grants NN12AR55G, 80NSSC18K0284, and 80NSSC18K1575; byproducts of the NEO search include images and catalogues from the survey area. This work was partially funded by Kepler/K2 grant J1944/80NSSC19K0112and HST GO-15889, and STFC grants ST/T000198/1 and ST/S006109/1. The ATLAS science products have been made possible through the contributions of the University of Hawaii Institute for Astronomy, the Queen’s University Belfast, the Space Telescope Science Institute, the South African Astronomical Observatory, and The Millennium Institute of Astrophysics (MAS), Chile.
\nThis work uses data obtained with eROSITA telescope onboard SRG observatory. The SRG observatory was built by Roskosmos with the participation of the Deutsches Zentrum für Luft- und Raumfahrt (DLR). The SRG/eROSITA X-ray telescope was built by a consortium of German Institutes led by MPE, and supported by DLR. The SRG spacecraft was designed, built, launched and is operated by the Lavochkin Association and its sub-contractors. The science data were downlinked via the Deep Space Network Antennae in Bear Lakes, Ussurijsk, and Baykonur, funded by Roskosmos. The eROSITA data used in this work were processed using the eSASS software system developed by the German eROSITA consortium and proprietary data reduction and analysis software developed by the Russian eROSITA Consortium.
\nSome of the data presented herein were obtained at Keck Observatory, which is a private 501(c)3 non-profit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the Native Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.
\nA major upgrade of the Kast spectrograph on the Shane 3 m telescope at Lick Observatory, led by Brad Holden, was made possible through gifts from the Heising-Simons Foundation, William and Marina Kast, and the University of California Observatories. Research at Lick Observatory is partially supported by a generous gift from Google.
\nBased on observations made with the Liverpool Telescope operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council.
\nPartly based on observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The NOT data were obtained under programme ID P68-501.
\nThis research has made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. Data analysis was performed using the NuSTAR Data Analysis Software (nustardas), jointly developed by the ASI Science Data Center (SSDC, Italy) and the California Institute of Technology (USA).
\n\nThe data behind Figs 1–5 are available at https://github.com/yaoyuhan/TDE-2024lhc-2024kmq/. Other data underlying this article that are not in the Appendix will be shared on reasonable request to the corresponding author.
",
"abstract": "We study AT2024kmq and AT2024lhc, two tidal disruption events (TDEs) with blue featureless spectra associated with high-mass black holes ($M_{\\rm BH}\\sim 10^8\\, \\mathrm{ M}_\\odot$). Both events show optical precursors consistent with shock dissipation from stream self-intersection. Their X-ray emission is luminous ($L_{\\rm X}\\sim 10^{44}\\, {\\rm erg\\, s^{-1}}$), highly variable (with minimum observed variability time-scales of 1.3 and 4.8 h for factor of ∼3 flux changes), long-lasting (>1 yr), emerging no later than the optical peak, and well characterized by power laws with $1.7\\lt \\Gamma \\lt 3$ (where $f_\\nu \\propto \\nu ^{1-\\Gamma }$). The X-ray properties and radio non-detections support a compact corona ($\\lesssim 10 r_{\\rm g}$) producing Comptonized X-ray emission. Using all published featureless TDEs, we find statistically significant bimodality in the distribution of their peak ultraviolet/optical blackbody luminosities and radii. We assemble a comparison TDE sample with early-time X-ray observations with eROSITA, in which we find different $M_{\\rm BH}$ distributions in TDEs with different X-ray spectral evolution properties: low-mass black holes ($M_{\\rm BH} \\sim 10^6 \\mathrm{ M}_\\odot$) remain soft ($\\Gamma \\gt 4$) within $t\\lesssim 2$ yr, intermediate masses ($\\sim 10^7 \\mathrm{ M}_\\odot$) transition from soft to hard at $\\sim$1 yr, while high masses ($\\sim 10^8 \\mathrm{ M}_\\odot$) are hard ($1.5\\lt \\Gamma \\lesssim 3$) from the outset. We interpret this result as evidence that the soft-to-hard state transition in TDEs occurs at the critical threshold of $\\dot{M}_{\\rm acc} \\sim 0.03 \\dot{M}_{\\rm Edd}$ (similar to X-ray binaries), using the fact that the transition time-scale predicted by simple disc theory scales with black hole mass as $t_{\\rm tr}\\propto M_{\\rm BH}^{-3/4}$.
",
"date": "2026-06",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "549",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "stag920",
"issn": "0035-8711",
"official_url": "https://authors.library.caltech.edu/records/2h94d-w9e28",
"funders": {
"items": [
{
"grant_number": "80NSSC25K7488"
},
{},
{},
{},
{
"grant_number": "075-15-2024-647"
},
{
"grant_number": "80NSSC24K0897"
},
{
"grant_number": "80NSSC25K7949"
},
{
"grant_number": "AST-2307668"
},
{},
{
"grant_number": "948381"
},
{
"grant_number": "PHY-2117997"
},
{
"grant_number": "PHY-2308862"
},
{
"grant_number": "PHY-2409481"
},
{},
{
"grant_number": "NAS5-26555"
},
{
"grant_number": "AST-1440341"
},
{
"grant_number": "AST-2034437"
},
{
"grant_number": "2407588"
},
{},
{
"grant_number": "12540303"
},
{
"grant_number": "NN12AR55G"
},
{
"grant_number": "80NSSC18K0284"
},
{
"grant_number": "80NSSC18K1575"
},
{
"grant_number": "J1944/80NSSC19K0112"
},
{
"grant_number": "GO-15889"
},
{
"grant_number": "ST/T000198/1"
},
{
"grant_number": "ST/S006109/1"
}
]
},
"local_group": {
"items": [
{
"id": "Palomar-Observatory"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
},
{
"id": "Zwicky-Transient-Facility"
},
{
"id": "Astronomy-Department"
},
{
"id": "Center-for-Data-Driven-Discovery"
},
{
"id": "Infrared-Processing-and-Analysis-Center-(IPAC)"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1093/mnras/stag920",
"primary_object": {
"basename": "stag920.pdf",
"url": "https://authors.library.caltech.edu/records/2h94d-w9e28/files/stag920.pdf"
},
"pub_year": "2026",
"author_list": "Yao, Yuhan; Chornock, Ryan; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8v7pf-x0c07",
"eprint_status": "archive",
"datestamp": "2026-06-03 21:36:53",
"lastmod": "2026-06-03 21:36:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Hutchins",
"given": "Tate"
}
},
{
"name": {
"family": "Kasapis",
"given": "Spiridon"
},
"orcid": "0000-0002-0972-8642"
},
{
"name": {
"family": "Farooki",
"given": "Hameedullah"
}
},
{
"name": {
"family": "Cuesta",
"given": "Manuel E."
},
"orcid": "0000-0002-7341-2992"
},
{
"name": {
"family": "Khoo",
"given": "Lengying"
},
"orcid": "0000-0003-0412-1064"
},
{
"name": {
"family": "Pak",
"given": "Sungmin"
},
"orcid": "0000-0003-2847-7110"
},
{
"name": {
"family": "Czarnota",
"given": "Robert"
}
},
{
"name": {
"family": "Rankin",
"given": "Jamie"
}
},
{
"name": {
"family": "Szalay",
"given": "Jamey"
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Zigong"
},
"orcid": "0000-0002-9246-996X"
},
{
"name": {
"family": "Livadiotis",
"given": "Georgios"
}
},
{
"name": {
"family": "Sarlis",
"given": "Nikolaos"
}
},
{
"name": {
"family": "McComas",
"given": "David"
},
"orcid": "0000-0002-9745-3502"
}
]
},
"title": "Solar Energetic Particle Prediction in the Inner Heliosphere Using Deep Learning and PSP/IS\u2299IS Data",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "solar energetic particles; machine learning; prediction; parker solar probe; solar dynamics observatory",
"note": "© 2026 The Author(s). Journal of Geophysical Research: Machine Learning and Computation published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
\n\n\n
We thank the IS\u2299IS team and everyone that made the PSP mission possible. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/PSP. Parker Solar Probe was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C).
\n
All figures were generated using Matplotlib version 3.2.1 (Hunter, 2007), available under the Matplotlib license at https://matplotlib.org/. The ML methods were implemented using the PyTorch library, which is publicly available at https://pytorch.org/. For the implementation of the above research, all relevant code can be found in the relevant Zenodo repository: https://doi.org/10.5281/zenodo.20292939. All of the computing and data storage for the model were done on Princeton University's Stellar cluster https://researchcomputing.princeton.edu/systems/stellar. The IS\u2299IS data are publicly available and can be downloaded at https://spp-isois.sr.unh.edu/. The authors have made all necessary efforts to comply with the NASA Transform to Open Science (TOPS) directive. More information about the NOAA Space Weather Scale used in this work can be found in https://www.swpc.noaa.gov/phenomena/solar-radiation-storm.
",
"abstract": "Solar events, such as coronal mass ejections and solar flares, accelerate large numbers of energetic charged particles, producing solar energetic particle (SEP) events that can harm astronauts, damage satellites, and potentially damage infrastructure on Earth. Previous machine learning (ML) SEP prediction models aimed to predict geoeffective events using data from Earth\u2010orbiting or Sun\u2010Earth Lagrange 1 (L1) point missions. However, predicting SEP events throughout the heliosphere is essential for supporting missions to Mars and other deep\u2010space destinations. This study uses EUV images from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) to predict particle intensity values observed by the Integrated Science Investigation of the Sun (IS\u2299IS) onboard the Parker Solar Probe (PSP), over various points in the ecliptic plane between Sun and Earth, using deep learning. The ML models extract features from SDO/AIA_(171A) images through a series of convolutional layers, combine them with PSP's trajectory, and process the fused representation using transformer and dense layers. The output is a regression estimate of the energy\u2010weighted average particle intensity (J_linlin), which is subsequently thresholded to yield a binary classification indicating whether J_(linlin) ≥ 0.1 counts/cm2 s sr keV. The best\u2010performing model achieves a probability of detection of 0.76, true skill score (TSS) of 0.47, F1 score of 0.47, false alarm rate (FAR) of 0.65 and precision of 0.35. These results are comparable to ML models that predict geoeffective events, opening avenues toward ML\u2010aided predictions in the inner\u2010heliosphere.
",
"date": "2026-06",
"date_type": "published",
"publication": "Journal of Geophysical Research: Machine Learning and Computation",
"volume": "3",
"number": "3",
"publisher": "American Geophysical Union",
"pagerange": "e2026JH001293",
"issn": "2993-5210",
"official_url": "https://authors.library.caltech.edu/records/8v7pf-x0c07",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Physics-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1029/2026jh001293",
"primary_object": {
"basename": "Journal of Geophysical Research Machine Learning and Computation - 2026 - Hutchins - Solar Energetic Particle Prediction.pdf",
"url": "https://authors.library.caltech.edu/records/8v7pf-x0c07/files/Journal of Geophysical Research Machine Learning and Computation - 2026 - Hutchins - Solar Energetic Particle Prediction.pdf"
},
"pub_year": "2026",
"author_list": "Hutchins, Tate; Kasapis, Spiridon; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7p6z1-cvs56",
"eprint_status": "archive",
"datestamp": "2026-05-30 01:25:59",
"lastmod": "2026-05-30 01:25:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Jel\u00ednek",
"given": "Martin"
},
"orcid": "0000-0003-3922-7416"
},
{
"name": {
"family": "Ierardi",
"given": "Annarita"
},
"orcid": "0009-0003-5392-2586"
},
{
"name": {
"family": "Novotn\u00fd",
"given": "Filip"
},
"orcid": "0009-0008-5788-3584"
},
{
"name": {
"family": "Oganesyan",
"given": "Gor"
},
"orcid": "0000-0001-9765-1552"
},
{
"name": {
"family": "Banerjee",
"given": "Biswajit"
},
"orcid": "0000-0002-8008-2485"
},
{
"name": {
"family": "Giannios",
"given": "Dimitrios"
},
"orcid": "0000-0003-1503-2446"
},
{
"name": {
"family": "Karpov",
"given": "Sergey"
},
"orcid": "0000-0003-0035-651X"
},
{
"name": {
"family": "Topinka",
"given": "Martin"
},
"orcid": "0000-0002-5711-9278"
},
{
"id": "Kammoun-Elias",
"name": {
"family": "Kammoun",
"given": "Elias"
},
"orcid": "0000-0002-0273-218X"
},
{
"name": {
"family": "\u0160trobl",
"given": "Jan"
},
"orcid": "0000-0002-4147-2878"
},
{
"name": {
"family": "Castro-Tirado",
"given": "Alberto J."
},
"orcid": "0000-0003-2999-3563"
}
]
},
"title": "Thermal electrons in an ultra-relativistic shock shape the optical afterglow of GRB 250702F",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "acceleration of particles; radiation mechanisms: non-thermal; shock waves; gamma-ray burst: individual: GRB 250702F; gamma-ray burst: general",
"note": "© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nWe thank Emanuele Sobacchi and Pasquale Blasi for the fruitful discussions. BB acknowledges financial support from the Italian Ministry of University and Research (MUR) for the PRIN grant METE under contract no. 2020KB33TP. This research has made use of data obtained through the High Energy Astrophysics Science Archive Research Center Online Service, provided by the NASA/Goddard Space Flight Center, and specifically this work made use of public Fermi-GBM and Fermi-LAT data. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. The critical early-time observations were obtained with the 0.5-m robotic telescope D50 at the Astronomical Institute of the Czech Academy of Sciences in Ondrejov, supported by the project RVO:67985815.
",
"abstract": "Observing early optical emission from gamma-ray bursts (GRBs) contemporaneous with the MeV prompt emission phase remains rare. Such observations require rapid-response robotic facilities. The Ond\u0159ejov D50 telescope detected the optical counterpart of GRB 250702F at z\u2004=\u20041.520 only 27.8 s after trigger, enabling high-cadence monitoring during the brightest prompt emission pulses. The optical light curve revealed two distinct flares. The first (30–100 s) is spectrally consistent with the MeV prompt emission. The second flare (100–1400 s) exhibits an unusual morphology (Fν\u2004∝\u2004t−α): a rapid rise turning gradually into a steep decay (α\u2004∼\u20041.6) before transitioning to a standard power-law afterglow (α\u2004=\u20040.79). This steep decay phase cannot be explained by non-thermal electrons accelerated at the forward shock, and a reverse-shock scenario is disfavoured due to the long duration of the flare and the temporal offset from the underlying deceleration time. We interpret the steep decay as the synchrotron frequency of a thermal (Maxwellian) electron population sweeping through the optical band. Modelling yields a non-thermal energy fraction of δ\u2004≈\u20040.8, with the remaining energy heating electrons at a characteristic Lorentz factor of γth\u2004∼\u2004900. These observations provide evidence of thermal electron signatures in GRB afterglows consistent with predictions from particle-in-cell simulations of ultra-relativistic collisionless shocks.
",
"date": "2026-06",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "710",
"publisher": "EDP Sciences",
"pagerange": "L1",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/7p6z1-cvs56",
"funders": {
"items": [
{
"grant_number": "2020KB33TP"
},
{
"grant_number": "RVO:67985815"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1051/0004-6361/202659667",
"primary_object": {
"basename": "aa59667-26.pdf",
"url": "https://authors.library.caltech.edu/records/7p6z1-cvs56/files/aa59667-26.pdf"
},
"pub_year": "2026",
"author_list": "Jel\u00ednek, Martin; Ierardi, Annarita; et al."
},
{
"id": "https://authors.library.caltech.edu/records/c96r1-pph33",
"eprint_status": "archive",
"datestamp": "2026-05-26 15:50:27",
"lastmod": "2026-05-26 15:50:27",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Dalal",
"given": "Bijoy"
},
"orcid": "0000-0001-8993-9118"
},
{
"name": {
"family": "Chakrabarty",
"given": "Dibyendu"
},
"orcid": "0000-0003-2693-5325"
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Srivastava",
"given": "Nandita"
},
"orcid": "0000-0002-0452-5838"
},
{
"name": {
"family": "Desai",
"given": "Mihir I."
},
"orcid": "0000-0002-7318-6008"
}
]
},
"title": "Investigation on Upstream Ion Events from the L1 Point Observation: New Insights",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Planetary bow shocks; Interplanetary physics",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe are grateful to all the members of the Wind/STEP team for constructing the STEP instrument and thereafter, generating and managing the dataset used in this work. We express our sincere gratitude to the Department of Space, Government of India for supporting this work.
\n\nThe STEP flux data are available at https://cdaweb.gsfc.nasa.gov/index.html. In addition to the STEP flux data, we have used data for the components of interplanetary magnetic field (IMF) that are available in the abovementioned site.
",
"abstract": "\n
There has been long-standing controversy regarding the origin and transport of short-lived energetic ion events observed upstream of the Earth’s bow shock. In this work, by adopting a unique method, we study the characteristics of 152 upstream ion events observed by the Suprathermal Energetic Particles (STEP) instrument on board the Wind satellite during 2012–2017. These events are selected manually based on rise and fall of H and 4He intensities. During nearly 80% of the selected upstream events, the local interplanetary magnetic field appears to be nearly radial. Using the multidirectional measurement capability of the STEP, we compare the 4He/H and CNO/H ratios as well as the spectral indices of H, 4He, and CNO in the Earth-facing sectors with those seen in the Sun-facing sectors. This exercise is repeated by applying 10–120 minute lags on the ion intensities measured in the Sun-facing sectors of the instrument. It is found that the composition ratios are well correlated, thus confirming that the origin of the ions seen in the opposite-facing directions is the same. Surprisingly, we find that the spectra measured in the Earth-facing sectors are generally softer during majority of the events as compared to those measured in the Sun-facing sectors, with the mean softening in H, 4He, and CNO spectra in the solar wind frame varying between ∼0.877 and 1.0, ∼1.068–1.116, and ∼1.4–1.939, respectively. We propose that scattering due to processes like cross-field diffusion could be responsible for producing the harder spectra in the Sun-facing sectors.
\n
© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
We thank the anonymous Referee for their careful review and constructive comments, which significantly improved the clarity and quality of this manuscript. The authors would like to thank the IS\u2299IS and the PSP mission teams. A.K. acknowledges financial support from the NASA contract NNN06AA01C (Solar Orbiter SIS, Parker Solar Probe EPI-Lo). S.R. acknowledges funding from Johns Hopkins University Applied Physics Laboratory independent R&D fund. A.K., E.P., and A.V. acknowledge financial support from NASA’s LWS grant 80NSSC25K0130. A.V. is supported by NASA’s grant Nos. 80NSSC24K0555 and 80NSSC22K1028. P.R. was supported by NASA (80NSSC22K0893, 80NSSC20C0187, and 80NSSC20K1285), NSF’s PREEVENTS program (ICER-1854790), and NRL (N00173-24-C-0004). I.C.J. acknowledges support from the Research Council of Finland (X-Scale, grant No. 371569). L.R.-G. acknowledges support through the European Space Agency (ESA) research fellowship program. Solar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. The Suprathermal Ion Spectrograph (SIS) is a European facility instrument funded by ESA under contract number SOL.ASTR.CON.00004. Solar Orbiter post-launch work at JHU/APL is supported by NASA contract NNN06AA01C, at the Southwest Research Institute by NASA 80GFSC25CA035. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory (JHU/APL) as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). We thank the STEREO: SECCHI SOHO: LASCO; SDO/AIA teams and Predictive Science Inc. for providing the data used in this study. The STEREO SECCHI data are produced by a consortium of RAL (UK), NRL (USA), LMSAL (USA), GSFC (USA), MPS (Germany), CSL (Belgium), IOTA (France), and IAS (France). SOHO is a mission of international cooperation between ESA and NASA. The SDO/AIA data used are courtesy of SDO (NASA) and the AIA consortium. Some data processing for this research was carried out using version 7.1.0 of the SunPy open-source software package (SunPy Community et al. 2020). This research has made use of PyThea v1.1.0, an open-source and free Python package to reconstruct the 3D structure of CMEs and shock waves (A. Kouloumvakos et al. 2022).
\n
We present a detailed investigation of the shock properties associated with solar energetic particle (SEP) events that exhibit a concave (\"nose-like\") shape in their energy spectrogram, characterized by inverse velocity arrival (IVA) of the particles, where high-energy particles arrive later than mid-energy ones. Using measurements from Solar Orbiter and Parker Solar Probe between 2018 and 2025, we identify 26 such SEP events and reconstruct the observed shock fronts in three dimensions. We derive shock parameters along the magnetic field lines connected to each spacecraft using kinematic modeling and coronal magnetohydrodynamic simulations. Our analysis indicates that IVA-SEP events arise due to the spatial and temporal evolution of the shock properties and magnetic connectivity. In most of the cases analyzed here, the magnetic connectivity starts on the flanks of coronal mass ejection-driven shocks, where shocks tend to be weak, and shifts toward the shock apex, sampling stronger portions of the shock front. This evolution of the shock properties at the connected field lines likely leads to the delayed arrival of high-energy particles and the progressive hardening of the SEP energy spectrum, observed in some of the events. We find a correlation between the transition energy at which the IVA begins and the shock speed along the connected field lines, consistent with expectations from time-dependent diffusive shock acceleration. Our results underscore the importance of the evolving shock properties, magnetic connectivity, and instrumental sensitivity in shaping SEP intensity profiles and the formation of IVA signatures.
",
"date": "2026-05-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "1002",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "188",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/cxbxz-6a886",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
},
{},
{
"grant_number": "80NSSC25K0130"
},
{
"grant_number": "80NSSC24K0555"
},
{
"grant_number": "80NSSC22K1028"
},
{
"grant_number": "80NSSC22K0893"
},
{
"grant_number": "80NSSC20C0187"
},
{
"grant_number": "80NSSC20K1285"
},
{
"agency": "National Science Foundation",
"grant_number": "ICER-1854790"
},
{
"agency": "NRL",
"grant_number": "N00173-24-C-0004"
},
{
"grant_number": "371569"
},
{
"grant_number": "SOL.ASTR.CON.00004"
},
{
"grant_number": "80GFSC25CA035"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/ae5e65",
"primary_object": {
"basename": "Kouloumvakos_2026_ApJ_1002_188.pdf",
"url": "https://authors.library.caltech.edu/records/cxbxz-6a886/files/Kouloumvakos_2026_ApJ_1002_188.pdf"
},
"pub_year": "2026",
"author_list": "Kouloumvakos, A.; Lario, D.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/x7m6p-k9a15",
"eprint_status": "archive",
"datestamp": "2026-05-06 16:59:35",
"lastmod": "2026-05-06 16:59:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Hristopulos",
"given": "D. T."
},
"orcid": "0000-0002-5189-5612"
},
{
"name": {
"family": "Khoo",
"given": "L. Y."
},
"orcid": "0000-0003-0412-1064"
},
{
"name": {
"family": "Cuesta",
"given": "M. E."
},
"orcid": "0000-0002-7341-2992"
},
{
"name": {
"family": "Kasapis",
"given": "S."
},
"orcid": "0000-0002-0972-8642"
},
{
"name": {
"family": "Livadiotis",
"given": "G."
},
"orcid": "0000-0002-7655-6019"
},
{
"name": {
"family": "Pak",
"given": "S."
},
"orcid": "0000-0003-2847-7110"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "C."
},
"orcid": "0000-0002-0978-8127"
}
]
},
"title": "Statistical Anatomy of a Solar Energetic Particle Event",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Time series analysis; Space plasmas; Heliosphere",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
We would like to thank the IS\u2299IS team and all those who made the PSP mission possible. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/PSP. PSP was designed, built, and operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star program (contract NNN06AA01C).
\n
Solar energetic particle (SEP) events exhibit complex variability, making their statistical characterization essential for constraining physical models and accurately modeling SEP dynamics. SEP transport is commonly modeled as a diffusive process. However, recent studies reveal persistent correlations in SEP propagation, suggesting that fractional Brownian motion (fBm) provides a suitable framework for representing nondiffusive transport because it accounts for correlated increments. In this work, we perform the first detailed evaluation of whether SEP flux time series conform to the fBm model, using IS\u2299IS data from the Parker Solar Probe mission. In particular, we test three defining properties of fBm: Gaussianity and stationarity of flux increments, and power-law scaling of the structure function. Our analysis of Low-Energy Telescope measurements across SEP phases and energy channels reveals phase- and energy-dependent behavior inconsistent with fBm, including nonlinear drift, volatility clustering, and heavy-tailed distributions. Consequently, stochastic generators based on fBm cannot reliably reproduce SEP fluxes. While structure functions exhibit power-law scaling with Hurst exponents H < 0.5, indicating anticorrelated increments, H varies with phase and energy without a consistent trend. Overall, SEP fluxes behave as stochastic processes with self-similarity, non-Gaussian statistics, and intermittent volatility—yet a unified statistical model that integrates these properties remains elusive.
",
"date": "2026-05-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "1002",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "112",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/x7m6p-k9a15",
"funders": {
"items": [
{
"agency": "National Aeronautics and Space Administration",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ae5ba1",
"primary_object": {
"basename": "Hristopulos_2026_ApJ_1002_112.pdf",
"url": "https://authors.library.caltech.edu/records/x7m6p-k9a15/files/Hristopulos_2026_ApJ_1002_112.pdf"
},
"pub_year": "2026",
"author_list": "Hristopulos, D. T.; Khoo, L. Y.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gx2yj-99f03",
"eprint_status": "archive",
"datestamp": "2026-04-27 22:30:31",
"lastmod": "2026-04-27 22:30:32",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Lo",
"given": "Ming-Yuan"
},
"orcid": "0009-0009-4551-376X"
},
{
"name": {
"family": "Guo",
"given": "Fan"
},
"orcid": "0000-0003-4315-3755"
},
{
"name": {
"family": "Giacalone",
"given": "Joe"
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Zhao",
"given": "Lulu"
},
"orcid": "0000-0003-3936-5288"
},
{
"name": {
"family": "Lario",
"given": "David"
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Koban",
"given": "Gergely"
},
"orcid": "0009-0006-2646-1501"
},
{
"name": {
"family": "Ho",
"given": "George C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
}
]
},
"title": "The Effect of Large-scale Magnetic Fluctuations on Energetic Particle Profiles across Interplanetary Shocks",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Interplanetary particle acceleration; Plasma astrophysics; Space plasmas",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
We acknowledge support in part from NASA grants 80HQTR21T0005 and NNH230B17A, and NNH24OB107. J.G. also acknowledges support from NASA under grants 80NSSC20K1283 and 80NSSC18K1213, the ISOIS instrument suite on NASA’s Parker Solar Probe under contract NNN06AA01C, and the NSF under grant 1931252. F.G. acknowledges NSF under grant 2334932. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231. The simulations also used resources provided by the Los Alamos National Laboratory Institutional Computing Program.
\n
\n
In situ observations of energetic particles associated with interplanetary (IP) shocks, known as energetic storm particle (ESP) events, often show time-intensity profiles quite different from predictions of classical diffusive shock acceleration theory. We use numerical simulations, including test-particle simulations and hybrid simulations (with fluid electrons and kinetic protons) for shocks propagating into a turbulent magnetic field to study the ESP intensity-time profiles across a strong IP shock. We find that several types of energetic particle intensity profiles similar to in situ observations can be produced in our simulations. The peak of energetic particle count is often near, but can be shifted from, the locations of the shock front, with the peak usually being observed downstream of the shock. These findings may help understand particle acceleration at both traveling IP shocks and shocks in other heliospheric and astrophysical environments.
",
"date": "2026-05-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "1002",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "10",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/gx2yj-99f03",
"funders": {
"items": [
{
"grant_number": "80HQTR21T0005"
},
{
"grant_number": "NNH230B17A"
},
{
"grant_number": "NNH24OB107"
},
{
"grant_number": "80NSSC20K1283"
},
{
"grant_number": "80NSSC18K1213"
},
{
"grant_number": "NNN06AA01C"
},
{
"agency": "National Science Foundation",
"grant_number": "1931252"
},
{
"agency": "National Science Foundation",
"grant_number": "2334932"
},
{
"grant_number": "DE-AC02-05CH11231"
}
]
},
"local_group": {
"items": [
{
"id": "Physics-Department"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ae5523",
"primary_object": {
"basename": "Lo_2026_ApJ_1002_10.pdf",
"url": "https://authors.library.caltech.edu/records/gx2yj-99f03/files/Lo_2026_ApJ_1002_10.pdf"
},
"pub_year": "2026",
"author_list": "Lo, Ming-Yuan; Guo, Fan; et al."
},
{
"id": "https://authors.library.caltech.edu/records/geha2-rt549",
"eprint_status": "archive",
"datestamp": "2026-04-20 20:45:34",
"lastmod": "2026-04-20 20:45:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Li",
"given": "S."
},
"orcid": "0009-0005-8520-0144"
},
{
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"name": {
"family": "Sudha",
"given": "M."
},
"orcid": "0000-0003-0440-7978"
},
{
"name": {
"family": "Brumback",
"given": "M. C."
},
"orcid": "0000-0002-4024-6967"
},
{
"name": {
"family": "Buisson",
"given": "D. J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"name": {
"family": "Coughenour",
"given": "B. M."
},
"orcid": "0000-0003-0870-6465"
},
{
"name": {
"family": "Di Marco",
"given": "A."
},
"orcid": "0000-0003-0331-3259"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"name": {
"family": "La Monaca",
"given": "F."
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Mastroserio",
"given": "G."
},
"orcid": "0000-0003-4216-7936"
},
{
"name": {
"family": "Rossland",
"given": "S."
},
"orcid": "0000-0001-6304-1035"
}
]
},
"title": "NuSTAR's Intentional Stray Light Observation of Scorpius X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Neutron stars; Low-mass x-ray binary stars",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
This work is supported by NASA under grant No. 80NSSC23K0498.
\n
\n
We present the first spectral analysis of Scorpius X-1 (Sco X-1) using intentional stray light (SL) observations taken by NuSTAR. Unlike focused observations that have high telemetry load when observing bright sources, intentional SL observations can help reduce the telemetry and reduce the effect of dead time, thereby maximizing the on-source exposure time, all of which are critical for extremely bright sources that exhibit short timescale variability like Sco X-1. The intentional SL observation of Sco X-1, taken in 2023, captured the source primarily in the flaring branch (FB) of the Z track. We performed spectral modeling of the continuum and reprocessed emission. A combination of thermal and Comptonization components (modeled with thcomp ) provided a robust fit to the continuum. We test both scenarios for Comptonized emitting regions arising from the accretion disk and close to the neutron star, which provides comparable fit statistics. Reflection was modeled with the relxillNS model, enabling measurements of disk inclination consistent with prior radio and IXPE studies and comparison of the inner disk radius to the emission radii of the thermal components. Overall, the results from the intentional SL data provide comparable results to literature on the focused NuSTAR data of Sco X-1 in the FB or taken contemporaneously. The success of this observation demonstrates the capability of SL data to yield high-quality spectral constraints comparable to focused observations, offering a powerful avenue for studying bright X-ray binaries with NuSTAR.
",
"date": "2026-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "1001",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "194",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/geha2-rt549",
"funders": {
"items": [
{
"agency": "National Aeronautics and Space Administration",
"grant_number": "80NSSC23K0498"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ae5898",
"primary_object": {
"basename": "Li_2026_ApJ_1001_194.pdf",
"url": "https://authors.library.caltech.edu/records/geha2-rt549/files/Li_2026_ApJ_1001_194.pdf"
},
"pub_year": "2026",
"author_list": "Li, S.; Ludlam, R. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/f57q9-db057",
"eprint_status": "archive",
"datestamp": "2026-04-02 16:47:21",
"lastmod": "2026-04-02 16:47:21",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Osborn",
"given": "N.E."
}
},
{
"name": {
"family": "Abarr",
"given": "Q."
}
},
{
"name": {
"family": "Akaike",
"given": "Y."
}
},
{
"name": {
"family": "Binns",
"given": "W.R."
},
"orcid": "0000-0001-6110-3407"
},
{
"name": {
"family": "Bose",
"given": "R.G."
}
},
{
"name": {
"family": "Brandt",
"given": "T.J."
}
},
{
"name": {
"family": "Braun",
"given": "D.L."
}
},
{
"name": {
"family": "Cannady",
"given": "N.W."
},
"orcid": "0000-0003-2916-6955"
},
{
"id": "Crabill-R-M",
"name": {
"family": "Crabill",
"given": "R.M."
}
},
{
"name": {
"family": "Dowkontt",
"given": "P.F."
}
},
{
"name": {
"family": "Fitzsimmons",
"given": "S.P."
}
},
{
"name": {
"family": "Hams",
"given": "T."
}
},
{
"name": {
"family": "Israel",
"given": "M.H."
}
},
{
"name": {
"family": "Krizmanic",
"given": "J.F."
}
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A.W."
},
"orcid": "0000-0001-9178-5349"
},
{
"name": {
"family": "Labrador",
"given": "W."
}
},
{
"name": {
"family": "Lisalda",
"given": "L."
},
"orcid": "0000-0002-5202-1642"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R.A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "J.W."
}
},
{
"name": {
"family": "Murphy",
"given": "R.P."
}
},
{
"name": {
"family": "de Nolfo",
"given": "G.A."
},
"orcid": "0000-0002-3677-074X"
},
{
"name": {
"family": "Nutter",
"given": "S."
}
},
{
"name": {
"family": "Olevitch",
"given": "M.A."
}
},
{
"name": {
"family": "Rauch",
"given": "B.F."
},
"orcid": "0000-0002-1452-4142"
},
{
"name": {
"family": "Sakai",
"given": "K."
}
},
{
"name": {
"family": "Sebastian",
"given": "S. San"
}
},
{
"name": {
"family": "Sasaki",
"given": "M."
}
},
{
"name": {
"family": "Simburger",
"given": "G.M."
}
},
{
"name": {
"family": "Tatoli",
"given": "T."
}
},
{
"name": {
"family": "Walsh",
"given": "N.E."
}
},
{
"name": {
"family": "Ward",
"given": "J.E."
}
},
{
"name": {
"family": "West",
"given": "A.T."
}
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M.E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Zober",
"given": "W.V."
}
}
]
},
"title": "SuperTIGER ultra-heavy galactic cosmic ray atmospheric corrections using Geant4 simulations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galactic cosmic rays; Simulations; Long-duration balloon; Antarctica",
"note": "© 2025 The Authors. Published by Elsevier B.V. on behalf of COSPAR.
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
\n\nThis research was supported by NASA under grants NNX09AC17G, NNX14AB25G, NNX15AC23G and 80NSSC20K0405, by the McDonnell Center for the Space Sciences at Washington University, and by the Peggy and Steve Fossett Foundation. We thank the NASA Columbia Scientific Balloon Facility, the NASA Balloon Program Office, and the NSF United States Antarctic Program for the excellent and highly professional efforts that resulted in two successful long-duration balloon flights for SuperTIGER.
\n
\nSuperTIGER was supported by Cecil J. Waddington at the University of Minnesota until he passed on October 1, 2020. SuperTIGER was also supported by Ed C. Stone at the California Institute of Technology until he passed on June 9, 2024. We would also like to acknowledge the retired engineers from NASA Goddard Space Flight Center W.M. Daniels and J. Hahne.
\n\nThis research was supported by NASA under grants NNX09AC17G, NNX14AB25G, NNX15AC23G and 80NSSC20K0405, by the McDonnell Center for the Space Sciences at Washington University, and by the Peggy and Steve Fossett Foundation.
\nThis work was supported by NASA under grants NNX09AC17G, NNX09AC18G, NNX14AB24G, NNX14AB25G, NNX15AC23G, 80NSSC20K0405, 80NSSC23K0055 and by the Peggy and Steve Fossett Foundation, and by the McDonnell Center for the Space Sciences at Washington University in St. Louis.
",
"abstract": "SuperTIGER (Super Trans-Iron Galactic Element Recorder) is a balloon-borne instrument designed to directly measure ultra-heavy Galactic cosmic-ray (UHGCR) nuclei. SuperTIGER had two successful Antarctic flights: SuperTIGER-1 in 2012 for 55 days, and SuperTIGER-2 in 2019 for 32 days. Stratospheric float altitudes varied between ∼ 36 – 40 km for the flights. To obtain top-of-atmosphere (TOA) abundances, the observed abundance measurements must be corrected for propagation through the residual ∼ 0.5% of atmosphere and inactive detector material. The approach developed for the previous TIGER instrument propagates TOA elemental abundances from satellite measurements down through the atmosphere to flight altitudes, accounting for gains and losses due to charge-changing nuclear interactions. Final TOA abundances are found by iteratively adjusting the assumed TOA abundances in the propagation model until the model produces instrument abundances that match the flight measurements. We develop a new method to obtain TOA abundances of UHGCR nuclei by simulating nuclear interactions and energy losses cosmic-ray nuclei experience propagating through the atmosphere using Geant4. We simulate a slab of atmosphere material as well as instrument material above the active detector and record energy loss and nuclear interactions of Galactic cosmic ray (GCR) projectiles. Results from these simulations are used to create a response matrix to describe the charge-changing losses or gains of cosmic-ray nuclei species. The simulation results are also used to obtain required TOA energy for cosmic-ray nuclei to trigger SuperTIGER's acrylic Cherenkov detector (320 MeV/nuc). We compare the TOA energy and TOA abundances from simulation-based corrections to previous analytical corrections.
",
"date": "2026-04-15",
"date_type": "published",
"publication": "Advances in Space Research",
"volume": "77",
"number": "8",
"publisher": "Elsevier",
"pagerange": "8323-8336",
"issn": "0273-1177",
"official_url": "https://authors.library.caltech.edu/records/f57q9-db057",
"funders": {
"items": [
{
"grant_number": "NNX09AC17G"
},
{
"grant_number": "NNX14AB25G"
},
{
"grant_number": "NNX15AC23G"
},
{
"grant_number": "80NSSC20K0405"
},
{},
{
"grant_number": "NNX09AC18G"
},
{
"grant_number": "NNX14AB24G"
},
{
"grant_number": "80NSSC23K0055"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1016/j.asr.2025.10.040",
"primary_object": {
"basename": "1-s2.0-S0273117725011718-main.pdf",
"url": "https://authors.library.caltech.edu/records/f57q9-db057/files/1-s2.0-S0273117725011718-main.pdf"
},
"pub_year": "2026",
"author_list": "Osborn, N.E.; Abarr, Q.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gbvjz-74c77",
"eprint_status": "archive",
"datestamp": "2026-04-14 21:07:36",
"lastmod": "2026-04-14 21:07:36",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Silver",
"given": "Ross"
},
"orcid": "0000-0001-6564-0517"
},
{
"name": {
"family": "Torres-Alb\u00e0",
"given": "N\u00faria"
},
"orcid": "0000-0003-3638-8943"
},
{
"name": {
"family": "Marchesi",
"given": "Stefano"
},
"orcid": "0000-0001-5544-0749"
},
{
"name": {
"family": "Gianolli",
"given": "Vittoria E."
},
"orcid": "0000-0002-9719-8740"
},
{
"name": {
"family": "Cox",
"given": "Isaiah"
},
"orcid": "0000-0003-2287-0325"
},
{
"name": {
"family": "Sengupta",
"given": "Dhrubojyoti"
},
"orcid": "0009-0002-6991-1534"
},
{
"name": {
"family": "Pal",
"given": "Indrani"
},
"orcid": "0000-0002-7825-1526"
},
{
"name": {
"family": "Ajello",
"given": "Marco"
},
"orcid": "0000-0002-6584-1703"
},
{
"id": "Zhao-Xiurui",
"name": {
"family": "Zhao",
"given": "Xiurui"
},
"orcid": "0000-0002-7791-3671"
},
{
"name": {
"family": "Imam",
"given": "Kouser"
},
"orcid": "0009-0003-3381-211X"
},
{
"name": {
"family": "Banerjee",
"given": "Anuvab"
},
"orcid": "0000-0001-7796-8907"
}
]
},
"title": "Compton-thick AGN in the NuSTAR Era. XI. Analyzing 11 CT-AGN Candidates Selected with Machine Learning",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; X-ray active galactic nuclei; Infrared astronomy; Linear regression; Spectral energy distribution",
"note": "© 2026. The Author(s). Published by the American Astronomical Society.
\n\n
\n
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n
\n
The material is based upon work supported by NASA under award No. 80GSFC24M0006.
\nThe authors thank the anonymous referee for the helpful comments that greatly improved our paper.
\nV.E.G. acknowledges funding under NASA contract 80NSSC24K1403.
",
"abstract": "\n
This work discusses the broadband X-ray spectral analysis of 11 candidate heavily obscured active galactic nuclei (AGN) selected based on their infrared and X-ray properties by a recently published machine learning algorithm. This paper is part of a larger work to identify and characterize all AGN in the local Universe (z < 0.1) with the largest line-of-sight (los) column densities (NH), the so-called Compton-thick (NH,los ≥ 1024 cm−2) AGN. We modeled the X-ray spectra using two physically motivated models: UXClumpy and RXTorusD. Of the 11 AGN in our sample, we found 3 to be obscured with 22.7 < LogNH,los ≤ 23.0, 5 with 23.0 < LogNH,los ≤ 23.25, and 3 with 23.4 < LogNH,los ≤ 23.9, according to UXClumpy. Meanwhile, according to RXTorusD, we found 3 AGN to be obscured with 22.7 < LogNH,los ≤ 23.0, 4 with 23.0 < LogNH,los ≤ 23.4, and 4 with 23.85 < LogNH,los ≤ 23.96. Additionally, this work served as a comparison between UXClumpy and RXTorusD. We found broad agreement between the two, with 8 of 11 sources agreeing on the value of the photon index Γ, while only 5 of 11 sources agree on the NH,los value within the 90% confidence level.
\n
© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
This work is partially funded via NASA grants 80NM0018F0577, 80NSSC22K0477, 80NSSC22K0718, and 80NSSC23K0169.
\n
\n
We investigate the effects of the nearby interstellar medium (ISM) on the locally measured cosmic-ray (CR) spectra. Using the G al P rop code, we explore how variations in the local gas and source distributions affect spectral features at low energies. Comparing with recent Voyager 1 measurements taken in the local ISM, we show that for a realistic interstellar gas distribution the data favor models in which there are no significant CR sources within ∼150–200 pc of the solar system, implying that the nearest dominant contributors to the low-energy CR flux are located at distances beyond this range. We find that the modeling supports the conclusion of A. C. Cummings et al. that there is a significant fraction of primary boron in its observed spectrum at low energies. Our study shows that detailed modeling of the immediate Galactic environment is required to robustly infer Galactic CR propagation parameters from local measurements and that accounting for nearby ISM structure can alleviate tensions between direct CR data and global propagation models.
",
"date": "2026-04-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "1001",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "17",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/cjxxd-ekr43",
"funders": {
"items": [
{
"grant_number": "80NM0018F0577"
},
{
"grant_number": "80NSSC22K0477"
},
{
"grant_number": "80NSSC22K0718"
},
{
"grant_number": "80NSSC23K0169"
}
]
},
"local_group": {
"items": [
{
"id": "Physics-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/ae4c57",
"primary_object": {
"basename": "Porter_2026_ApJ_1001_17.pdf",
"url": "https://authors.library.caltech.edu/records/cjxxd-ekr43/files/Porter_2026_ApJ_1001_17.pdf"
},
"pub_year": "2026",
"author_list": "Porter, T. A.; Moskalenko, I. V.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mr0qs-j7e53",
"eprint_status": "archive",
"datestamp": "2026-04-06 17:14:50",
"lastmod": "2026-04-06 17:14:51",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Drake",
"given": "J. F."
},
"orcid": "0000-0002-9150-1841"
},
{
"name": {
"family": "Swisdak",
"given": "M."
},
"orcid": "0000-0001-9898-464X"
},
{
"name": {
"family": "Fitzmaurice",
"given": "A."
},
"orcid": "0009-0001-9646-9668"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Phan",
"given": "T."
},
"orcid": "0000-0002-6924-9408"
},
{
"name": {
"family": "Berland",
"given": "G."
},
"orcid": "0000-0001-6010-6374"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "Rahmati",
"given": "A."
},
"orcid": "0000-0003-0519-6498"
},
{
"name": {
"family": "Whittlesey",
"given": "P."
},
"orcid": "0000-0002-7287-5098"
},
{
"name": {
"family": "Livi",
"given": "R."
},
"orcid": "0000-0002-0396-0547"
},
{
"name": {
"family": "Larson",
"given": "D."
},
"orcid": "0000-0001-5030-6030"
}
]
},
"title": "Proton and Heavy Ion Acceleration by Magnetic Reconnection at the Near-Sun Heliospheric Current Sheet",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar magnetic reconnection",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
This work was supported by NASA’s Parker Solar Probe Mission, contract NNN06AA01C. We thank all the scientists and engineers who have worked hard to make PSP a successful mission, in particular the engineers, scientists, and administrators who designed and built IS\u0298IS/EPI-Lo, IS\u0298IS/EPI-Hi, FIELDS, and SWEAP instrument suites, and support their operations and the scientific analysis of its data. For their contributions to the scientific configuration and instrumental analysis, we owe special thanks to P. Kollmann, J. Peachy, and J. Vandegriff at JHU/APL for EPI-Lo. PSP data are available at the NASA Space Physics Data Facility. Work at SwRI is supported in part under NASA grants 80NSSC20K1815, 80NSSC18K1446, 80NSSC21K0112, 80NSSC20K1255, and 80NSSC21K0971. W.H.M. is partially supported by the PSP/IS\u0298IS project at the University of Delaware, subcontract SUB0000317 from Princeton University, and by NASA PSP Guest Investigator grant 80NSSC21K1765. A.F. was supported by NASA grant 80NSSC23K1625. J.F.D. and M.S. were supported by the FIELDS team of the Parker Solar Probe (NNN06AA01C), by NASA grants 80NSSC20K1813, 80NSSC22K0352, and 80NSSC25K7754, and NSF grant PHY2109083.
\n
Magnetic reconnection at the near-Sun heliospheric current sheet (HCS) dissipates the Parker spiral and converts magnetic energy into plasma kinetic energy. During Encounter 14 at a radial distance of ~16.25 R\u2299, Parker Solar Probe observed an HCS crossing where reconnection-driven acceleration—likely facilitated by merging large-scale flux tubes—energized protons up to ∼400 keV. This energy gain is ≈1000 times greater than the available magnetic energy per particle. We present here a comprehensive analysis of pitch-angle distributions and differential energy spectra for protons and heavy ions (He, O, and Fe) in conjunction with local wave activity during this crossing. Our results provide the first direct in situ observations of simultaneous proton and heavy-ion energization during HCS reconnection. Crucially, we find that heavy-ion power-law spectral indices differ significantly from those of protons, contradicting previous simulations that predict species-independent slopes. We further demonstrate that ion beams and anisotropies produced during reconnection drive waves in the ion cyclotron range of frequencies. Finally, we show that proton pitch-angle scattering is stronger than that of heavy ions, which may account for the flatter spectra or harder spectral indices observed in the heavy-ion populations. These observations provide definitive evidence for in situ reconnection-driven acceleration at the near-Sun HCS and necessitate the inclusion of species-dependent transport and acceleration efficiencies in contemporary reconnection-based particle energization models.
",
"date": "2026-04-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "1000",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "300",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/mr0qs-j7e53",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
},
{
"grant_number": "80NSSC20K1815"
},
{
"grant_number": "80NSSC18K1446"
},
{
"grant_number": "80NSSC21K0112"
},
{
"grant_number": "80NSSC20K1255"
},
{
"grant_number": "80NSSC21K0971"
},
{
"grant_number": "SUB0000317"
},
{
"grant_number": "80NSSC21K1765"
},
{
"grant_number": "80NSSC23K1625"
},
{
"grant_number": "80NSSC20K1813"
},
{
"grant_number": "80NSSC22K0352"
},
{
"grant_number": "80NSSC25K7754"
},
{
"agency": "National Science Foundation",
"grant_number": "PHY2109083"
}
]
},
"local_group": {
"items": [
{
"id": "Physics-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/ae48f2",
"primary_object": {
"basename": "Desai_2026_ApJ_1000_300.pdf",
"url": "https://authors.library.caltech.edu/records/mr0qs-j7e53/files/Desai_2026_ApJ_1000_300.pdf"
},
"pub_year": "2026",
"author_list": "Desai, M. I.; Drake, J. F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kwrtf-99870",
"eprint_status": "archive",
"datestamp": "2026-04-01 20:03:28",
"lastmod": "2026-04-01 20:03:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Zigong"
},
"orcid": "0000-0002-9246-996X"
},
{
"name": {
"family": "Wimmer-Schweingruber",
"given": "Robert F."
},
"orcid": "0000-0002-7388-173X"
},
{
"name": {
"family": "Berger",
"given": "Lars"
},
"orcid": "0009-0007-6389-8443"
},
{
"name": {
"family": "K\u00fchl",
"given": "Patrick"
},
"orcid": "0000-0002-3758-9272"
},
{
"name": {
"family": "Kollhoff",
"given": "Alexander"
},
"orcid": "0000-0002-9471-5132"
},
{
"name": {
"family": "Heber",
"given": "Bernd"
},
"orcid": "0000-0003-0960-5658"
},
{
"name": {
"family": "B\u00f6ttcher",
"given": "Stephan I."
}
},
{
"name": {
"family": "Yang",
"given": "Liu"
},
"orcid": "0000-0002-6416-1538"
},
{
"name": {
"family": "Heidrich-Meisner",
"given": "Verena"
},
"orcid": "0000-0003-3502-8778"
},
{
"name": {
"family": "Strauss",
"given": "Roelf Du Toit"
},
"orcid": "0000-0002-0205-0808"
},
{
"name": {
"family": "Gomez-Herrero",
"given": "Ra\u00fal"
},
"orcid": "0000-0002-5705-9236"
},
{
"name": {
"family": "Rodriguez-Pacheco",
"given": "Javier"
},
"orcid": "0000-0002-4240-1115"
},
{
"name": {
"family": "Pacheco",
"given": "Daniel"
},
"orcid": "0000-0002-6176-4077"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "Richard A."
},
"orcid": "0000-0002-0156-2414"
}
]
},
"title": "Anomalous cosmic rays within the inner heliosphere: Observations of helium by the High Energy Telescope on board Solar Orbiter",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: heliosphere; Sun: particle emission; interplanetary medium",
"note": "© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nSolar Orbiter is a mission of international cooperation be-tween ESA and NASA, operated by ESA. This work was supported by the German Federal Ministry for Economic Affairs and Energy and the German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt, e.V., (DLR)), grant number 50OT2002. Special thanks are given to C. Cohen and A. Cummings for multiple rounds of insightful discussion. The author also thanks Y. Wang and C. Corti for their assistance with the GCR model data.
",
"abstract": "Context. The radial gradients of cosmic rays are key parameters in studies of the transport of particles in space. Solar Orbiter, launched on 2020 February 10, approaches the Sun approximately every half-a-year, with its closest perihelion distance of 0.29 au at the end of 2022 during the nominal mission phase. The two double-ended high-energy telescopes (HET) on board Solar Orbiter measure energetic particles in the energy range between a few MeV/nuc and a few hundreds of MeV/nuc. These particles are dominated by anomalous cosmic rays (ACRs) and galactic cosmic rays (GCRs) during solar quiet times.
\nAims. By obtaining the radial gradient of ACR helium in the inner heliosphere, we can advance our understanding of how the transport of cosmic rays is affected by the particle drift effect and the large-scale magnetic field.
\nMethods. We analyzed helium observations at Solar Orbiter/HET between 11.1 and 49 MeV/nuc. Since our study is focused on quiet time measurements, we removed the periods of solar energetic particle (SEP) events. The intensities were averaged over the Carrington rotation period. The helium observations from the Electron Proton and Helium Instrument (EPHIN) on board SOHO were utilized as the baseline to correct the long-term variation caused by the solar modulations.
\nResults. We present the first observation of ACR helium at Solar Orbiter/HET between February 2020 and July 2022 in the inner heliosphere before the sun became fully active. We derived a radial gradient of ACR helium of between 0.3 and 1 au. The averaged radial gradient between 11.1 and 49 MeV/nuc is about 22 ± 4%/au and the averaged value between 11.1 and 41.2 MeV/nuc was raised to 32 ± 8%/au after removing the GCR contribution, which was estimated using a GCR model. In addition, the temporal variation of radial gradients indicates that gradients tend to increase with the enhancement of the solar modulation and the increased tilt angle of the heliospheric current sheet.
",
"date": "2026-04",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "708",
"publisher": "EDP Sciences",
"pagerange": "A36",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/kwrtf-99870",
"funders": {
"items": [
{
"grant_number": "50OT2002"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1051/0004-6361/202558218",
"primary_object": {
"basename": "aa58218-25.pdf",
"url": "https://authors.library.caltech.edu/records/kwrtf-99870/files/aa58218-25.pdf"
},
"pub_year": "2026",
"author_list": "Xu, Zigong; Wimmer-Schweingruber, Robert F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/e0xsm-3yq63",
"eprint_status": "archive",
"datestamp": "2026-04-14 22:25:44",
"lastmod": "2026-04-14 22:25:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Shang",
"given": "Wensai"
},
"orcid": "0000-0002-7078-8249"
},
{
"name": {
"family": "Liu",
"given": "Ji"
},
"orcid": "0000-0001-6648-8908"
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Zigong"
},
"orcid": "0000-0002-9246-996X"
},
{
"name": {
"family": "Yue",
"given": "Chao"
},
"orcid": "0000-0001-9720-5210"
},
{
"name": {
"family": "Guo",
"given": "Ruilong"
},
"orcid": "0000-0002-7125-0942"
},
{
"name": {
"family": "Xiao",
"given": "Chao"
},
"orcid": "0000-0002-2633-9526"
},
{
"name": {
"family": "Shi",
"given": "Quanqi"
},
"orcid": "0000-0001-6835-4751"
},
{
"name": {
"family": "Wimmer-Schweingruber",
"given": "Robert F."
},
"orcid": "0000-0002-7388-173X"
},
{
"name": {
"family": "Guo",
"given": "Jingnan"
},
"orcid": "0000-0002-8707-076X"
},
{
"name": {
"family": "Degeling",
"given": "Alexander W."
},
"orcid": "0000-0001-7338-9270"
},
{
"name": {
"family": "Rankin",
"given": "Robert"
}
},
{
"name": {
"family": "Tian",
"given": "Anmin"
}
},
{
"name": {
"family": "Zong",
"given": "Qiu-Gang"
}
},
{
"name": {
"family": "Han",
"given": "Chenyao"
},
"orcid": "0009-0008-6476-0734"
},
{
"name": {
"family": "Park",
"given": "Jong-Sun"
},
"orcid": "0000-0002-2732-1168"
},
{
"name": {
"family": "Wang",
"given": "Huizi"
},
"orcid": "0000-0002-3652-6210"
},
{
"name": {
"family": "Liu",
"given": "Wenlong"
}
},
{
"name": {
"family": "Fu",
"given": "Suiyan"
},
"orcid": "0000-0002-3858-1555"
},
{
"name": {
"family": "Zhai",
"given": "L. M."
},
"orcid": "0000-0002-7294-9691"
},
{
"name": {
"family": "Chen",
"given": "D."
},
"orcid": "0000-0002-6109-0113"
},
{
"name": {
"family": "Ni",
"given": "Sulan"
},
"orcid": "0000-0002-2873-0860"
},
{
"name": {
"family": "Chen",
"given": "T. L."
},
"orcid": "0000-0002-2944-2422"
}
]
},
"title": "A galactic cosmic ray cavity in Earth-Moon space",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2026 the Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).
\n\nWe thank Z. Yao, M. Wang, J. Lu, S. Fu, X. Kong, Z. Xing, S. Yao, Y. X. Wang, L. Xie, Y. M. Wang, C. Shen, D. Han, F. He, X. Zhou, H. Zhang, J. Liu, J. Chen, B. Xia, and X. Shen for helpful discussions. We acknowledge NASA contract NAS5-02099 and V. Angelopoulos for the use of data from the ARTEMIS Mission. We specifically thank C. W. Carlson and J. P. McFadden for the use of ESA data and K. H. Glassmeier, U. Auster, and W. Baumjohann for the use of FGM data.
\n\nThis work is supported by the National Natural Science Foundation of China (grants 42225405 to Q.S., 42274200 to C.Y., 42304172 to C.X., 42304185 to H.W., 42188101 to J.G., and 42521007 to J.G.), the Shandong Provincial Natural Science Foundation (ZR2023ZD36 to Q.S., ZR2023JQ016 to R.G., ZR2023QD119 to H.W., and ZR2023QA141 to S.N.), and the National Key R&D Program of China (2023YFC2808900 to C.Y.). J.L. and R.R. acknowledge financial support from the Canadian Space Agency and Natural Sciences and Engineering Research Council of Canada. The development and build of LND were supported by the German Aerospace Center (DLR) Space Administration, Bonn, under grant 50 JR 1604 to the Christian-Albrechts-University (CAU) Kiel and by the Beijing Municipal Science and Technology Commission (grant Z181100002918003) to the National Space Science Center (NSSC) and the National Natural Science Foundation of China grant 41941001. A.W.D. acknowledges support from the National Natural Science Foundation of China, Research Fund for International Scholars (NSFC RFIS lev3, grant 42350710200), and the Shandong Provincial Government “Double Hundred” Program (WSR2023038).
\n\n\n\n\n\n\n\n\n
\n\nSupplementary Text; Figs. S1 and S2; Table S1
",
"abstract": "In regions of the Solar System distant from planetary magnetic fields, galactic cosmic rays (GCRs) have generally been assumed to be uniformly distributed over the Earth-Moon distance. However, our analysis of data from the LND (Lunar Lander Neutron and Dosimetry) experiment onboard the Chang'E-4 lander revealed a region of reduced GCR flux in the prenoon sector of the lunar orbit. Further investigation suggests the presence of an energetic particle cavity, formed by Earth's magnetic field acting as an obstacle to GCR propagation. This cavity indicates that the influence of Earth's magnetic field within the space environment extends unexpectedly up to and far beyond the lunar orbit. This finding offers the potential to avoid high radiation levels during future lunar exploration and deep-space missions.
",
"date": "2026-03-27",
"date_type": "published",
"publication": "Science Advances",
"volume": "12",
"number": "13",
"publisher": "American Association for the Advancement of Science",
"pagerange": "eadv1908",
"issn": "2375-2548",
"official_url": "https://authors.library.caltech.edu/records/e0xsm-3yq63",
"funders": {
"items": [
{
"grant_number": "42225405"
},
{
"grant_number": "42274200"
},
{
"grant_number": "42304172"
},
{
"grant_number": "42304185"
},
{
"grant_number": "42188101"
},
{
"grant_number": "42521007"
},
{
"agency": "Shandong Provincial Natural Science Foundation",
"grant_number": "ZR2023ZD36"
},
{
"agency": "Shandong Provincial Natural Science Foundation",
"grant_number": "ZR2023JQ016"
},
{
"agency": "Shandong Provincial Natural Science Foundation",
"grant_number": "ZR2023QD119"
},
{
"agency": "Shandong Provincial Natural Science Foundation",
"grant_number": "ZR2023QA141"
},
{
"agency": "National key R&D program of China",
"grant_number": "2023YFC2808900"
},
{},
{},
{
"agency": "German Aerospace Center",
"grant_number": "50 JR 1604"
},
{
"grant_number": "Z181100002918003"
},
{
"grant_number": "41941001"
},
{
"grant_number": "42350710200"
},
{
"agency": "Shandong Provincial Government",
"grant_number": "WSR2023038"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1126/sciadv.adv1908",
"pmcid": "PMC13015879",
"primary_object": {
"basename": "sciadv.adv1908.pdf",
"url": "https://authors.library.caltech.edu/records/e0xsm-3yq63/files/sciadv.adv1908.pdf"
},
"related_objects": [
{
"basename": "sciadv.adv1908_sm.pdf",
"url": "https://authors.library.caltech.edu/records/e0xsm-3yq63/files/sciadv.adv1908_sm.pdf"
}
],
"pub_year": "2026",
"author_list": "Shang, Wensai; Liu, Ji; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ex9a8-5ak48",
"eprint_status": "archive",
"datestamp": "2026-03-17 16:21:21",
"lastmod": "2026-03-17 16:21:22",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zhao-Xiurui",
"name": {
"family": "Zhao",
"given": "Xiurui"
},
"orcid": "0000-0002-7791-3671"
},
{
"name": {
"family": "Ajello",
"given": "Marco"
},
"orcid": "0000-0002-6584-1703"
},
{
"name": {
"family": "Civano",
"given": "Francesca"
},
"orcid": "0000-0002-2115-1137"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Kammoun-Elias",
"name": {
"family": "Kammoun",
"given": "Elias"
},
"orcid": "0000-0002-0273-218X"
},
{
"name": {
"family": "Marchesi",
"given": "Stefano"
},
"orcid": "0000-0001-5544-0749"
},
{
"name": {
"family": "Shen",
"given": "Yue"
},
"orcid": "0000-0003-1659-7035"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Yang",
"given": "Qian"
},
"orcid": "0000-0002-6893-3742"
},
{
"id": "Boorman-Peter-G",
"name": {
"family": "Boorman",
"given": "Peter G."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"name": {
"family": "Pizzetti",
"given": "Andrealuna"
},
"orcid": "0000-0001-6412-2312"
},
{
"name": {
"family": "Silver",
"given": "Ross"
},
"orcid": "0000-0001-6564-0517"
},
{
"name": {
"family": "Sokolovsky",
"given": "Kirill V."
},
"orcid": "0000-0001-5991-6863"
},
{
"name": {
"family": "Stone",
"given": "Zachary"
},
"orcid": "0000-0002-8501-3518"
},
{
"name": {
"family": "Torres-Alb\u00e0",
"given": "Nuria"
},
"orcid": "0000-0003-3638-8943"
},
{
"name": {
"family": "Wu",
"given": "Qiaoya"
},
"orcid": "0000-0003-4202-1232"
},
{
"name": {
"family": "Zhu",
"given": "Peixin"
},
"orcid": "0000-0002-1333-147X"
}
]
},
"title": "Transient Relativistic Iron Emission Line from an X-Ray Flaring Supermassive Black Hole",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors thank the anonymous referee for insightful comments on the manuscript. X.Z. acknowledges the support from NASA funding 80NSSC24K1031. We appreciate the Targets of Opportunity observation from the Neil Gehrels Swift Observatory. This research has made use of data obtained from the Chandra Data Archive and software provided by the Chandra X-ray Center (CXC). This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work makes use of the data from SDSS. Funding for the Sloan Digital Sky Survey has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions.
\nThis paper employs a list of Chandra datasets, obtained by the Chandra X-ray Observatory, contained in DOI: 10.25574/cdc.517.
\n\nCXO - Chandra X-ray Observatory satellite, XMM - Newton X-Ray Multimirror Mission satellite.
",
"abstract": "\n
We report the discovery of the first transient relativistic iron Kα line in an active galactic nucleus (AGN), J1047+5907. The line was detected 21.5 days (rest frame) after an X-ray coronal flare was observed in 2008, and it exhibits significant broadening consistent with relativistic reflection from the accretion disk in the vicinity of the central supermassive black hole (SMBH). The line has a width of ∼300 eV, corresponding to a Keplerian velocity of 14,000 km s−1, at a distance of 5–41 light-days from the SMBH, strongly implying that the observed coronal flare triggered the emergence of the line. This event provides rare direct evidence of the response of the accretion disk to impulsive coronal illumination and offers a new method to probe the SMBH and disk physics. The relativistic modeling favors a broadened line produced by distant reflection from an accretion disk around a rapidly spinning black hole viewed at an intermediate inclination, consistent with other observations. Systematic monitoring of type 1 AGN following strong X-ray flares may open a new observational window into the innermost regions of AGN, enabling constraints on the physics of SMBH and its accretion disk at different radii that are otherwise challenging to access.
\n
© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins University Applied Physics Laboratory (JHU/APL) as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. Solar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. The Suprathermal Ion Spectrograph (SIS) is a European facility instrument funded by ESA under contract number SOL.ASTR.CON.00004. We thank ESA and NASA for their support of the Solar Orbiter and the other missions whose data were used in this letter. Solar Orbiter postlaunch work at JHU/APL is supported by NASA contract NNN06AA01C, at the Southwest Research Institute by NASA 80GFSC25CA035, and at CAU by German Space Agency (DLR) grant No. 50OT2002. C.M.S.C. acknowledges additional partial funding from NASA grant Nos. 80NSSC22K0893, 80NSSC21K1327, 80NSSC20K1815, 80NSSC23M0191, 80NSSC24K0175, and 80NSSC19K0067. This research has made use of PyThea v1.1.0, an open-source and free Python package to reconstruct the 3D structure of CMEs and shock waves (Zenodo, doi:10.5281/zenodo.5713659). We thank the IRAP, PSI, and Solar-MACH teams for making their tools publicly available, and CDAW, CACTus, and SolarSoft for curating and maintaining their online solar catalogs.
\n
\n
\n
Occasionally, solar energetic particle (SEP) events associated with fast, wide coronal mass ejections (CMEs) driving interplanetary shocks exhibit Fe/O abundance ratios that are significantly higher than the nominal value of 0.134. The cause of this enrichment in Fe remains unclear, but there are two prevailing theories: contribution from flare-accelerated material, and reacceleration of suprathermal remnant flare material by a quasiperpendicular shock. The 2024 July 23 SEP event was observed by four spacecraft spread over ∼160° of solar longitude and 0.4 au in radial distance. We examine the H, He, O, and Fe spectra and He/H and Fe/O abundance ratios observed at each spacecraft, and find that three measured Fe/O ratios >0.6 were relatively independent of energy. The fourth spacecraft measured strongly energy-dependent Fe/O ratios reaching very low values of 0.02 at a few MeV nuc−1. In an effort to evaluate the plausibility of the two explanations for Fe-rich SEP events, we studied the magnetic connection of the spacecraft to the solar source and the evolving CME; the velocity dispersion of the first arriving particles; and the time evolution of the Fe/O ratios. We also noted the pre-event CME and flare activity. We find that neither scenario is clearly consistent with the compositional variations between the four spacecraft, but more detailed modeling of the magnetic connections between the spacecraft and the solar source and the propagating shock may be beneficial.
\n
© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the journal referee for constructive criticism. This work has made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. The scientific results reported in this article are based on data obtained from the Chandra Data Archive. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application packages CIAO, ChIPS, and Sherpa. This research made use of the crossmatch service provided by CDS, Strasbourg.
\nLOFAR data products were provided by the LOFAR Surveys Key Science project (LSKSP; https://lofar-surveys.org/) and were derived from observations with the International LOFAR Telescope (ILT). LOFAR is the Low Frequency Array designed and constructed by ASTRON. It has observing, data processing, and data storage facilities in several countries, which are owned by various parties (each with its own funding sources), and which are collectively operated by the ILT foundation under a joint scientific policy. The efforts of the LSKSP have benefited from funding from the European Research Council, NOVA, NWO, CNRS-INSU, the SURF Co-operative, the UK Science and Technology Funding Council, and the Jülich Supercomputing Centre.
\nWe acknowledge the use of Hubble Advanced Products available at the Mikulski Archive for Space Telescopes. This research has made use of NASA’s Astrophysics Data System Bibliographic Services. This research has made use of data obtained through the High Energy Astrophysics Science Archive Research Center Online Service, provided by the NASA/Goddard Space Flight Center.
\nThe HST data are available at MAST: doi:10.17909/avwb-jy09. This paper employs a list of Chandra datasets, obtained by the Chandra X-ray Observatory, contained in doi:10.25574/cdc.532.
\n\nXMM - Newton X-Ray Multimirror Mission satellite, NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, CXO - Chandra X-ray Observatory satellite, HST - Hubble Space Telescope satellite.
\n\nCIAO (v.4.17), SAS (v.21.0.0), XSPEC (v 12.10.1; K. A. Arnaud 1996), Astropy (Astropy Collaboration et al. 2013, 2018).
",
"abstract": "\n
Giant radio sources (GRSs) harbor the Universe’s largest structures generated by individual galaxies, with projected source sizes exceeding 700 kpc. These enigmatic objects have been mainly studied at radio frequencies, and their physical properties in the high-energy domain are poorly understood. Here we present the results of a multiwavelength study focused on NuSTAR J112829+5831.8 (J1128+5831), the only known GRS serendipitously detected with the Nuclear Spectroscopic Telescope Array. Being located in proximity to the famous interacting galaxy system, Arp 299, J1128+5831 has been serendipitously observed also by the Chandra X-ray Observatory, Hubble Space Telescope, and XMM-Newton satellites. From radio observations with the Low Frequency Array, the NRAO VLA Sky Survey, and the Very Large Array Sky Survey, we have determined that J1128+5831 has an overall steep radio spectrum (α = −0.86; Fν ∝ να) and a low core dominance (CD = −2.4, in log-scale), indicating the source to be viewed at large angles. From the X-ray spectral analysis, we found J1128+5831 to harbor an obscured active galactic nucleus (AGN) with neutral hydrogen column density exceeding 1023 cm−2. Its optical spectrum, taken with the Dark Energy Spectroscopic Instrument, exhibits prominent narrow emission lines but lacks broad components, thus confirming J1128+5831 to be a Type 2 AGN powered by a radiatively efficient accreting system. Overall, the broadband properties of J1128+5831 are consistent with those observed for the general GRS population.
\n
© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the anonymous referee for their insightful and valuable input into our manuscript, which improved its quality.
\nNuSTAR is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).
\nThis research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
\n\nNuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission.
\n\nHEASoft (Nasa High Energy Astrophysics Science Archive Research Center (Heasarc) 2014), NuSTARDAS, XSPEC (K. A. Arnaud 1996).
",
"abstract": "\n
Fast X-ray transients (FXTs) are flashes of X-rays that last for a few hundreds of seconds to a few hours. An enigmatic population of these transients that did not have a clear origin has been known for several decades, mostly found serendipitously in soft X-ray imaging observations. Recent progress in this field by the Einstein Probe has found that many FXTs are associated with gamma-ray bursts and the collapse of massive stars. Motivated by this, we searched the NuSTAR archive in the harder 3–79 keV band for ∼1000 s duration transients. From 204 Ms of exposure, we present five candidate FXTs, four of which are spectrally hard, with power-law indices −3 < Γ < 0, setting them apart from FXTs discovered in the soft band. Three have potential associations with galaxies at z = 0.1–2, implying 3–79 keV luminosities of 1043–1048 erg s−1 and volumetric event rates of 125–2900 Gpc−3 yr−1. The properties of these NuSTAR FXTs most resemble low-luminosity gamma-ray bursts and would be much more common than their higher-luminosity counterparts in this redshift range.
\n
© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
",
"abstract": "Context. Active galactic nuclei (AGNs) exhibit significant variability across the electromagnetic spectrum on a wide range of timescales. This variability is particularly extreme in the X–ray band, showing both high-amplitude and rapid fluctuations. Power spectral density (PSD) analysis is a common tool used to characterise the observed variability in these objects. Although PSDs of AGN are typically well described by a bending power-law model, the dependence of the model parameters on photon energy has not been systematically explored in the past.
\nAims. Our objective is to investigate whether the PSD parameters of AGNs depend on energy, considering two low-mass Seyfert galaxies – NGC 4051 and NGC 4395 – as case studies. Both sources are highly variable in X-rays, and they have been observed extensively with current and past X-ray satellites. Using all archival observations, we aim to measure their power spectra over a broad frequency and energy range and investigate if and how the power spectrum evolves with energy.
\nMethods. We used archival data from XMM-Newton, Suzaku, and NuSTAR, and computed the power spectrum in six energy bands from 0.3 to 20 keV. Then we fitted the power spectra with a bending power-law model and investigated the energy dependence of the model parameters.
\nResults. The power spectra computed using light curves taken from different satellites and at different times are consistent within the errors, indicating that the X-ray variability process is stationary in these two objects. We found that, for both sources: a) the PSD bending frequency remains constant with the energy, b) the high-frequency slope becomes flatter with increasing energy, and c) the power spectrum amplitude decreases with increasing energy.
\nConclusions. Our results can significantly constrain current models that explain the variability of X-rays in AGNs (such as the fluctuating accretion rate model). Similar studies of more AGNs are necessary to quantify in detail the energy dependence of the power spectrum in AGNs.
",
"date": "2026-03",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "707",
"publisher": "EDP Sciences",
"pagerange": "A180",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/na923-wyg83",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1051/0004-6361/202557606",
"primary_object": {
"basename": "aa57606-25.pdf",
"url": "https://authors.library.caltech.edu/records/na923-wyg83/files/aa57606-25.pdf"
},
"pub_year": "2026",
"author_list": "Diamantopoulos, V. A.; Papadakis, I. E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/me6p1-gsr16",
"eprint_status": "archive",
"datestamp": "2026-03-07 17:00:46",
"lastmod": "2026-03-10 03:30:26",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Paterson",
"given": "Sarah"
},
"orcid": "0000-0003-2147-9586"
},
{
"name": {
"family": "Hannah",
"given": "Iain G"
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W"
},
"orcid": "0000-0002-1984-2932"
},
{
"name": {
"family": "Krucker",
"given": "S\u00e4m"
}
},
{
"name": {
"family": "Lastufka",
"given": "Erica"
}
},
{
"name": {
"family": "Hudson",
"given": "Hugh S"
},
"orcid": "0000-0001-5685-1283"
},
{
"name": {
"family": "Glesener",
"given": "Lindsay"
}
},
{
"name": {
"family": "White",
"given": "Stephen M"
}
},
{
"name": {
"family": "Smith",
"given": "David M"
}
}
]
},
"title": "Quiet Sun impulsive events observed with NuSTAR during solar minimum",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: atmosphere; Sun: corona; Sun: filaments, prominences; Sun: flares; Sun: X-rays, gamma rays",
"note": "© The Author(s) 2026. Published by Oxford University Press on behalf of Royal Astronomical Society.
\n\n
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
\n
This paper made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NUSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy), and the California Institute of Technology (USA). Hinode is a Japanese mission developed and launched by ISAS/JAXA, with NAOJ as domestic partner and NASA and UKSA as international partners. It is operated by these agencies in co-operation with ESA and NSC (Norway). AIA on the Solar Dynamics Observatory is part of NASA’s Living with a Star programme. This research has made use of SunPy, an open-source and free community-developed solar data analysis package written in python (The SunPy Community et al. 2020). This research made use of astropy, a community-developed core python package for Astronomy (Astropy Collaboration 2013, 2018, 2022). SP acknowledges support from the UK’s Science and Technology Facilities Council (STFC) doctoral training grant (ST/T506102/1). IGH acknowledges support from a Royal Society University Fellowship (URF/R/180010) and STFC grants (ST/T000422/1 and ST/X000990/1).
\n\nAll the data used in this paper are publicly available. In particular, NuSTAR via the NuSTAR Master Catalog with the OBSIDs 80512218001–80512228001 for the 2020 February 21 observation, and 80600201001 and 80610202001–80610210001 for 2020 September 12–13.
",
"abstract": "The investigation of small-scale energy release in the Sun's atmosphere is important in understanding how the corona is heated. Previous work has been able to study small EUV and SXR brightenings outside of active regions (i.e. the quiet Sun), but with HXRs this has mostly focused on active region transients/microflares due to the sensitivity of available telescopes. In this paper we present observations of the quiet Sun with the Nuclear Spectroscopic Telescope Array (NuSTAR), an X-ray imaging spectrometer with much greater sensitivity than previous instruments, allowing the observation of faint events. During the recent solar minimum, NuSTAR captured seven quiet Sun flares/impulsive brightenings, three on 21 February 2020, and four on 12–13 September 2020. From fitting their NuSTAR HXR spectra we find temperatures of 3.1–4.0 MK and emission measures between (0.75–17.0) × 10\u2074³ cm\u207b³, which gives thermal energies between (2.5–8.9) × 10²\u2076 erg. Only one event, a mini-filament eruption, showed evidence of slightly higher temperatures emission, confirmed through Differential Emission Measure analysis. None of the events showed evidence of non-thermal emission in their NuSTAR spectra, and we placed upper limits to the accelerated electron population. The thermal parameters for these quiet Sun events seem to scale differently to previously studied active region flares, suggesting a different energy release process might be dominating. However, this conclusion is affected by the different sensitivity and biases introduced by the various instruments and analysis approaches used.
",
"date": "2026-03",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "546",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "stag109",
"issn": "0035-8711",
"official_url": "https://authors.library.caltech.edu/records/me6p1-gsr16",
"funders": {
"items": [
{},
{
"grant_number": "ST/T506102/1"
},
{
"grant_number": "URF/R/180010"
},
{
"grant_number": "ST/T000422/1"
},
{
"grant_number": "ST/X000990/1"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.1093/mnras/stag109",
"primary_object": {
"basename": "stag109.pdf",
"url": "https://authors.library.caltech.edu/records/me6p1-gsr16/files/stag109.pdf"
},
"pub_year": "2026",
"author_list": "Paterson, Sarah; Hannah, Iain G; et al."
},
{
"id": "https://authors.library.caltech.edu/records/pdxtg-n0e58",
"eprint_status": "archive",
"datestamp": "2026-03-11 19:20:41",
"lastmod": "2026-03-11 19:20:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Mitchell-J-G",
"name": {
"family": "Mitchell",
"given": "J. G."
}
},
{
"id": "Bruno-A",
"name": {
"family": "Bruno",
"given": "A."
}
},
{
"id": "Albaijes-D",
"name": {
"family": "Albaijes",
"given": "D."
}
},
{
"id": "Bailey-Newman-S",
"name": {
"family": "Bailey\u00a0Newman",
"given": "S."
}
},
{
"id": "Boggs-R-C",
"name": {
"family": "Boggs",
"given": "R. C."
}
},
{
"id": "Choi-M-K",
"name": {
"family": "Choi",
"given": "M. K."
}
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cook-Walter-Richardson-III",
"name": {
"family": "Cook",
"given": "W. R."
}
},
{
"id": "Darwish-Y-S",
"name": {
"family": "Darwish",
"given": "Y. S."
}
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"id": "de-Nolfo-G-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
}
},
{
"id": "Dumonthier-J-J",
"name": {
"family": "Dumonthier",
"given": "J. J."
}
},
{
"id": "Garnett-R-D",
"name": {
"family": "Garnett",
"given": "R. D."
}
},
{
"id": "Gkioulidou-M",
"name": {
"family": "Gkioulidou",
"given": "M."
}
},
{
"id": "Gregory-K-J",
"name": {
"family": "Gregory",
"given": "K. J."
}
},
{
"id": "Guzman--Garcia-D",
"name": {
"family": "Guzman\u00a0Garcia",
"given": "D."
}
},
{
"id": "Haas-J-P",
"name": {
"family": "Haas",
"given": "J. P."
}
},
{
"id": "Hollenhorst-C",
"name": {
"family": "Hollenhorst",
"given": "C."
}
},
{
"id": "Jeunon-M",
"name": {
"family": "Jeunon",
"given": "M."
}
},
{
"id": "Kaiser-M-A",
"name": {
"family": "Kaiser",
"given": "M. A."
}
},
{
"id": "Kanekal-S-G",
"name": {
"family": "Kanekal",
"given": "S. G."
}
},
{
"id": "Kecman-Branislav",
"name": {
"family": "Kecman",
"given": "B."
}
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "Richard A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Letzer-J-D",
"name": {
"family": "Letzer",
"given": "J. D."
}
},
{
"id": "Liceaga-Indart-I",
"name": {
"family": "Liceaga\u00a0Indart",
"given": "I."
}
},
{
"id": "McComas-D-J",
"name": {
"family": "McComas",
"given": "D. J."
}
},
{
"id": "McNeel-B",
"name": {
"family": "McNeel",
"given": "B."
}
},
{
"id": "Muro-Gabriel-D",
"name": {
"family": "Muro",
"given": "G. D."
},
"orcid": "0000-0003-0581-1278"
},
{
"id": "Nolan-J-T",
"name": {
"family": "Nolan",
"given": "J. T."
}
},
{
"id": "Ogindo-M",
"name": {
"family": "Ogindo",
"given": "M."
}
},
{
"id": "Petrowich-P",
"name": {
"family": "Petrowich",
"given": "P."
}
},
{
"id": "Reaves-W-J",
"name": {
"family": "Reaves",
"given": "W. J."
}
},
{
"id": "Rosnack-T-P",
"name": {
"family": "Rosnack",
"given": "T. P."
}
},
{
"id": "Saghafi-N",
"name": {
"family": "Saghafi",
"given": "N."
}
},
{
"id": "Salerno-C-L",
"name": {
"family": "Salerno",
"given": "C. L."
}
},
{
"id": "Schwadron-N-A",
"name": {
"family": "Schwadron",
"given": "N. A."
}
},
{
"id": "Silber-M-A",
"name": {
"family": "Silber",
"given": "M. A."
}
},
{
"id": "Smith-E-S",
"name": {
"family": "Smith",
"given": "E. S."
}
},
{
"id": "Smith-M-T",
"name": {
"family": "Smith",
"given": "M. T."
}
},
{
"id": "Su\u00e1rez-G",
"name": {
"family": "Su\u00e1rez",
"given": "G."
}
},
{
"id": "Tatoli-T",
"name": {
"family": "Tatoli",
"given": "T."
}
},
{
"id": "Tiu-C-P",
"name": {
"family": "Tiu",
"given": "C. P."
}
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "Mark Edward"
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Windhausen-M-H",
"name": {
"family": "Windhausen",
"given": "M. H."
}
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Z."
},
"orcid": "0000-0002-9246-996X"
}
]
},
"title": "The High-Energy Ion Telescope (HIT) for the Interstellar Mapping And Acceleration Probe (IMAP) Mission",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2026, This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
\n\nThis work is supported by the IMAP mission as part of NASA’s Solar Terrestrial Probes (STP) mission line (80GSFC19C0027). A.B. acknowledges support from NASA under award 80GSFC24M0006.
\n\nC.M.S.C acknowledges membership on the Space Science Reviews editorial board. The other authors have no conflicts of interest to declare that are relevant to the content of this article.
",
"abstract": "The Interstellar Mapping and Acceleration Probe (IMAP; McComas et al. in Space Sci Rev 214:116, 2018a; McComas et al. in Space Sci Rev 221:100, 2025) is a NASA mission designed to study two of the most important issues in heliophysics: the interaction of the solar wind with the local interstellar medium and the acceleration of energetic particles. These two puzzles are surprisingly intertwined because particle acceleration in the inner heliosphere plays a large role in the interactions at the edge of the heliosphere. The ten instruments on IMAP, situated near the Earth-Sun L1 Lagrange point, include both in situ and remote-sensing observations and are designed to work together to explore these questions. The High-energy Ion Telescope (HIT), described herein, measures in situ ions from hydrogen through nickel at energies ranging from a few MeV/nucleon to some tens of MeV/nucleon, depending upon species. While the primary focus of HIT is Solar Energetic Particles (SEPs), HIT is also sensitive to Anomalous Cosmic Rays (ACRs) and Galactic Cosmic Rays (GCRs) that are also present at these energies. Working with the other IMAP instruments, HIT studies how the variation in SEP intensities, spectra, anisotropies, and composition inform the acceleration processes that generate these particles, and, in turn, how these high-energy particles affect the outer heliosphere. This paper details the design and operation of the HIT instrument.
",
"date": "2026-02-27",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "222",
"publisher": "Springer Science and Business Media LLC",
"pagerange": "23",
"issn": "0038-6308",
"official_url": "https://authors.library.caltech.edu/records/pdxtg-n0e58",
"funders": {
"items": [
{
"grant_number": "80GSFC19C0027"
},
{
"grant_number": "80GSFC24M0006"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1007/s11214-026-01279-6",
"primary_object": {
"basename": "s11214-026-01279-6.pdf",
"url": "https://authors.library.caltech.edu/records/pdxtg-n0e58/files/s11214-026-01279-6.pdf"
},
"pub_year": "2026",
"author_list": "Christian, E. R.; Mitchell, J. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/txkc7-wz840",
"eprint_status": "archive",
"datestamp": "2026-01-23 20:51:03",
"lastmod": "2026-01-23 20:51:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Zaidouni",
"given": "Fatima"
},
"orcid": "0000-0003-0931-0868"
},
{
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"name": {
"family": "Kosec",
"given": "Peter"
},
"orcid": "0000-0003-4511-8427"
},
{
"name": {
"family": "Behar",
"given": "Ehud"
},
"orcid": "0000-0001-9735-4873"
},
{
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Koss",
"given": "Michael"
},
"orcid": "0000-0002-7998-9581"
},
{
"name": {
"family": "Jur\u00e1\u0148ov\u00e1",
"given": "A."
},
"orcid": "0000-0002-7292-6852"
},
{
"id": "Kammoun-Elias",
"name": {
"family": "Kammoun",
"given": "Elias"
},
"orcid": "0000-0002-0273-218X"
},
{
"name": {
"family": "Brenneman",
"given": "Laura W."
},
"orcid": "0000-0003-2663-1954"
},
{
"name": {
"family": "Chakraborty",
"given": "Joheen"
},
"orcid": "0000-0002-0568-6000"
},
{
"name": {
"family": "Ebisawa",
"given": "Ken"
},
"orcid": "0000-0002-5352-7178"
},
{
"name": {
"family": "Eckart",
"given": "Megan E."
},
"orcid": "0000-0003-3894-5889"
},
{
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"name": {
"family": "Fukazawa",
"given": "Yasushi"
},
"orcid": "0000-0002-0921-8837"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gu",
"given": "Liyi"
},
"orcid": "0000-0001-9911-7038"
},
{
"name": {
"family": "Masterson",
"given": "Megan"
},
"orcid": "0000-0003-4127-0739"
},
{
"name": {
"family": "Ogawa",
"given": "Shoji"
},
"orcid": "0000-0002-5701-0811"
},
{
"name": {
"family": "Okajima",
"given": "Takashi"
},
"orcid": "0000-0002-6054-3432"
},
{
"name": {
"family": "Paltani",
"given": "St\u00e9phane"
},
"orcid": "0000-0002-8108-9179"
},
{
"name": {
"family": "Rogantini",
"given": "Daniele"
},
"orcid": "0000-0002-5359-9497"
},
{
"name": {
"family": "Terashima",
"given": "Yuichi"
},
"orcid": "0000-0003-1780-5481"
},
{
"name": {
"family": "Williams",
"given": "Brian J."
},
"orcid": "0000-0003-2063-381X"
},
{
"name": {
"family": "Yamada",
"given": "Satoshi"
},
"orcid": "0000-0002-9754-3081"
}
]
},
"title": "XRISM Finds the Changing-look Active Galactic Nucleus NGC 1365 in an Extended Low State: A Dense, Highly Ionized Outflow Obscures the Central Source",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray active galactic nuclei; Astrophysical black holes; X-ray astronomy; High resolution spectroscopy; High energy astrophysics; Seyfert galaxies; Active galactic nuclei",
"note": "© 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nF.Z. and E.K. acknowledge support by NASA grant 80NSSC25K7065. P.K. acknowledges support from the NASA Hubble Fellowship grant HST-HF2-51534.001—A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. E.B. and A.J. acknowledge support from NASA grant 80NSSC25K0082. M.E. acknowledges support from the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. S.O. acknowledges support from the Japan Society for the Promotion of Science (JSPS) KAKENHI grant No. 24K17104 (S.O.). Part of this research employs a list of Chandra datasets, obtained by the Chandra X-ray Observatory, contained in 10.25574/cdc.509.
\n\nHEAsoft (Nasa High Energy Astrophysics Science Archive Research Center (Heasarc) 2014), SPEX (J. S. Kaastra et al. 1996), SAS (C. Gabriel et al. 2004), CIAO (A. Fruscione et al. 2006).
",
"abstract": "\n
We present the first XRISM/Resolve observations of the active galactic nucleus NGC 1365, obtained in 2024 February and July. NGC 1365 is known for rapid transitions between Compton-thick and Compton-thin states, along with strong absorption from a highly ionized wind. During our observations, the source was found in a persistent low-flux state, characterized by a decrease in hard-X-ray luminosity and significant line-of-sight obscuration. In this state, XRISM/Resolve reveals clear Fe xxv and Fe xxvi absorption lines together with, for the first time in this source, corresponding emission lines. These features may arise either from reemission from a photoionized wind (P Cygni profile) or from collisionally ionized gas associated with outflow-driven shocks in the interstellar medium. We estimate the wind launch radius to be approximately 1016 cm (∼104Rg), consistent with the location of the X-ray broadline region. We also resolve a broadened Fe Kα line by σ ∼ 1300 km s−1, placing it at similar scales to the wind, consistent with radii inferred from disk-broadening models and the variability of the Fe Kα broad line. The similarity of the Fe Kα profile to the Hβ wing and broad Paα width indicates that the X-ray-emitting region is likely cospatial with the optical/infrared broadline region and originates from the same gas.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors would like to thank the IS\u2299IS and the PSP mission teams. G.D.B. and A.K. acknowledge financial support from the NASA PSP EPI-Lo contract NNN06AA01C. A.K. also acknowledges the support of NASA’s HGIO grant 80NSSC24K0555. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/PSP. The EPI-Hi LET geometric factor corrections from S. Pak et al. (2025) and EPI-Lo ChanC 4He efficiency corrections used in this work will be available in future data releases. PSP was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). Solar Orbiter/STIX data are accessed through https://datacenter.stix.i4ds.net, GOES X-ray data through the Space Weather Prediction Center (SWPC) at https://services.swpc.noaa.gov/json/goes/primary/, and SOHO/LASCO data are retrieved from https://lasco-www.nrl.navy.mil/index.php?p=content/retrieve/products.
",
"abstract": "\n
The Parker Solar Probe Integrated Science Investigation of the Sun (IS\u2299IS) instrument suite measured a variety of suprathermal and energetic particle events during orbits 18 and 19. We provide an overview of key features of the observations to provide guidance critical to making progress on complicated, integrated data sets like those provided by IS\u2299IS. In this work, we analyze and describe observations of particle acceleration signatures associated with coronal mass ejection (CME)–driven shocks and solar flares from 2023 November to 2024 March as measured by the IS\u2299IS/Energetic Particle Instrument-Low Energy and Energetic Particle Instrument-High Energy particle detectors. We present energy spectra for protons through Fe ions from ∼10 keV nuc−1 to >10 MeV nuc−1, abundance ratios, and time series analyses for seven solar energetic particle (SEP) events with respect to the magnetic field and plasma context provided by the FIELDS and Solar Wind Electrons Alphas and Protons instruments, respectively. For SEP events in orbits 18 and 19, we find that acceleration driven by multiple CMEs in succession have larger variability in 4He/H and Fe/O ratios than singular CMEs, that flare-associated SEP events preferentially accelerate higher mass-to-charge ratio particles, and that shock upstream transients may be present in CME-driven interplanetary shocks.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
This project was supported by the IS\u2299IS instrument suite on NASA’s Parker Solar Probe Mission, contract NNN06AA01C. Parker Solar Probe was designed and built, and is now operated, by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star program. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. J.G. also acknowledges support from the NSF/AGS under grant 1931252, and NASA under grants 80NSSC20K1283, 80NSSC18K1213, and 80NSSC21K0119. All data shown in this paper came from the Space Physics Data Facility at Goddard Space Flight Center using the Coordinated Data Analysis Web.
\n
\n
\n
On 2023 March 13, Parker Solar Probe was located about 0.23 au from the Sun when it was crossed by a very fast interplanetary shock. The intensities of ∼0.08–10 MeV energetic protons were markedly enhanced at the shock crossing. At energies from ∼0.1 to 1 MeV, the intensity at the shock was 3–4 orders of magnitude larger than it was ∼4 hr prior. In this study, we investigate the possible source of particles that led to this enhancement. Pre-existing high-energy particles that were present during the few-hour period prior to the shock could possibly serve as a source, assuming they are accelerated to even higher energies by the shock. We apply a “seeds test”—which determines the expected enhancement at the shock—to test this. We find that none of the pre-existing particle populations identified can account for the observed enhancement at the shock. The solar wind itself provides a very abundant source. To test whether shock-heated thermal solar wind could account for the source, we perform a series of self-consistent hybrid plasma simulations of this event and make direct comparisons with the observed particle spectra and magnetic field. We conclude that shock-heated solar wind protons are the source of energetic particles in this event. The direct comparisons of our simulations and observations also suggest that the shock was moving about 1350 km s−1 and had an Alfvén Mach number of about 4, both of which are considerably lower than previously estimated.
\n
© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nSolar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. The Suprathermal Ion Spectrograph (SIS) is a European facility instrument funded by ESA during construction, and NASA funds the instrument during Phase E operation. Solar Orbiter post-launch work at SwRI is supported by NASA contract 80GSFC25CA035, and we thank NASA headquarters and the NASA/GSFC Solar Orbiter project office for their continuing support. JRP acknowledges the financial support by the Spanish Ministerio de Ciencia, Innovación y Universidades FEDER/MCIU/AEI Projects ESP2017-88436-R and PID2019- 104863RB-I00/AEI/10.13039/501100011033. RFWS thanks ESA for supporting the build of SIS under contract number SOL.ASTR.CON.00004; the German Federal Ministry for Economic Affairs and Energy and the German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt, e.V., (DLR)) for their unwavering support under grant numbers 50OT0901, 50OT1202, 50OT1702, and 50OT2002; and the University of Kiel and the Land Schleswig-Holstein for their support of SIS. RCA acknowledges support from NASA grant 80NSSC21K0733. RCA and RJF additionally thank NASA grant 80NSSC24K0908. RCA and SKV acknowledge support from NASA grant 80NSSC22K0993. We acknowledge the Community Coordinated Modeling Center (CCMC) at Goddard Space Flight Center for the use of the DONKI catalog.
",
"abstract": "Investigations of solar energetic particles (SEPs) have long utilized the dispersive nature of onset times, as in, the earlier arrival of higher-energy particles compared to lower-energy particles, to infer information such as the path length to the acceleration site at the time of initial particle release. However, recent observations by Solar Orbiter and Parker Solar Probe have begun to characterize SEP events with an apparent delay in arrival times of the higher energy portion of the particle distribution, above a critical energy separating the delayed particles from that of the typical velocity dispersion signature at lower energies. Features of these delayed maximum energy (DME) SEP events, sometimes referred to as \"inverse velocity dispersion\" events, could provide new insight into the impacts of magnetic connectivity to locations along an expanding coronal mass ejection-driven (CME-driven) shock wave, variations of acceleration along the shock surface, and transport effects in the inner heliosphere. This study focuses on the occurrence rate and characteristics of DME events observed by Solar Orbiter relative to their footpoint locations with respect to the initial flare site. These DME events show a bias in occurrence rate towards events when the observer's footpoints were westward of the associated flare location. Additionally, estimated locations at which the highest-energy particles of DME events are released into the flux tube suggest continued release of increasingly higher-energy particles from the CME-driven shock into the connected flux tube well into the inner heliosphere. This indicates that DME events could be attributed to inner heliospheric effects and are not actually coronal in origin. This finding is consistent with previous observations and interpretations of SEP events connected westward of the associated flare.
",
"date": "2026-01",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "705",
"publisher": "EDP Sciences",
"pagerange": "A126",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/gbmd3-b4a08",
"funders": {
"items": [
{
"grant_number": "80GSFC25CA035"
},
{
"agency": "Ministerio de Universidades",
"grant_number": "ESP2017-88436-R"
},
{
"agency": "Ministerio de Universidades",
"grant_number": "PID2019-104863RB-I00/AEI/10.13039/501100011033"
},
{
"grant_number": "50OT0901"
},
{
"grant_number": "50OT1202"
},
{
"grant_number": "50OT1702"
},
{
"grant_number": "50OT2002"
},
{
"grant_number": "80NSSC21K0733"
},
{
"grant_number": "80NSSC24K0908"
},
{
"grant_number": "80NSSC22K0993"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1051/0004-6361/202557079",
"primary_object": {
"basename": "aa57079-25.pdf",
"url": "https://authors.library.caltech.edu/records/gbmd3-b4a08/files/aa57079-25.pdf"
},
"pub_year": "2026",
"author_list": "Allen, R. C.; Ho, G. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/n18ee-mqg16",
"eprint_status": "archive",
"datestamp": "2026-01-12 23:01:42",
"lastmod": "2026-01-12 23:01:42",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Alterman",
"given": "B. L."
}
},
{
"name": {
"family": "Baker",
"given": "D. N."
}
},
{
"name": {
"family": "Bruno",
"given": "A."
}
},
{
"name": {
"family": "Bzowski",
"given": "M."
}
},
{
"name": {
"family": "Christian",
"given": "E. R."
}
},
{
"name": {
"family": "Cohen",
"given": "I. J."
}
},
{
"name": {
"family": "Dalla",
"given": "S."
}
},
{
"name": {
"family": "Dayeh",
"given": "M. A."
}
},
{
"name": {
"family": "Desai",
"given": "M. I."
}
},
{
"name": {
"family": "Elliott",
"given": "H. A."
}
},
{
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Gkioulidou",
"given": "M."
}
},
{
"name": {
"family": "Guo",
"given": "F."
}
},
{
"name": {
"family": "Horbury",
"given": "T."
}
},
{
"name": {
"family": "Kanekal",
"given": "S. G."
}
},
{
"name": {
"family": "Kowalska-Leszczy\u0144ska",
"given": "I."
}
},
{
"name": {
"family": "Lee",
"given": "C. O."
}
},
{
"name": {
"family": "Livadiotis",
"given": "G. I."
}
},
{
"name": {
"family": "Luhmann",
"given": "J. G."
},
"orcid": "0000-0003-0626-9353"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
}
},
{
"name": {
"family": "McComas",
"given": "D. J."
}
},
{
"name": {
"family": "Mitchell",
"given": "J. G."
}
},
{
"name": {
"family": "Moebius",
"given": "E."
}
},
{
"name": {
"family": "Rankin",
"given": "J."
}
},
{
"name": {
"family": "Richardson",
"given": "J. D."
}
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
}
},
{
"name": {
"family": "Skoug",
"given": "R."
}
},
{
"name": {
"family": "Turner",
"given": "D."
}
},
{
"name": {
"family": "Zank",
"given": "G."
}
},
{
"name": {
"family": "Zirnstein",
"given": "E. J."
}
}
]
},
"title": "IMAP's Role in Understanding Particle Injection and Energization Throughout the Heliosphere",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliosphere; Interstellar medium; ENAs; Space weather; Energetic particles; Solar wind; Plasma; Magnetic fields; IMAP",
"note": "© The Author(s) 2026. This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
\n\n\n
\n
This work is supported by the IMAP mission as a part of NASA’s Solar Terrestrial Probes (STP) mission line (80GSFC19C0027). M.B. and I.K-L. were supported by contract for the GLOWS experiment from Polish Ministry for Education and Science MEiN/2021/2/DIR Polish. M.B. acknowledges support from Polish National Science Centre (NCN) grant 2023/51/B/ST9/01921, and I.K-L. from NCN grant 2024/53/B/ST9/01154. A.B. acknowledges support from NASA under award number 80GSFC24M0006. B.L.A. acknowledges NASA grants 80NSSC22K0645 (LWS/TM) and 80NSSC22K1011 (LWS). M.A.D. acknowledges partial support from NASA awards 80NSSC24K0908 and 80NSSC25K7687.
\n
\n
\n
\n
C.M.S.C acknowledges membership on the Space Science Reviews editorial board. The other authors have no conflicts of interest to declare that are relevant to the content of this article.
\n
\n
Table 1 Comparison of the measurement capabilities of the various spacecraft in the L1 fleet, with a special focus on the capabilities introduced by IMAP.
",
"abstract": "The payload of the Interstellar Mapping and Acceleration Probe (IMAP) includes sophisticated in situ instruments to measure solar wind plasma and magnetic fields, suprathermal and energetic particles at 1 au as well as unprecedented remote sensing instruments to observe the energetic neutral atoms (ENAs) in the outer heliosphere and the ultraviolet glow of the interstellar neutral H interacting with the three-dimensional solar wind. This unique combination of sensors on a single platform allows connections to be made between the inner and outer heliosphere to an extent never before possible. This article focuses on the scientific theme of connecting the physics of particle acceleration and transport throughout the heliosphere. Such studies enabled by IMAP are organized into three broad categories: i) fundamental particle acceleration and transport processes, ii) heliospheric variability that affects those processes, and iii) inner heliospheric science.",
"date": "2026-01",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "222",
"number": "1",
"publisher": "Springer Science and Business Media LLC",
"pagerange": "6",
"issn": "0038-6308",
"official_url": "https://authors.library.caltech.edu/records/n18ee-mqg16",
"funders": {
"items": [
{
"grant_number": "80GSFC19C0027"
},
{
"grant_number": "MEiN/2021/2/DIR"
},
{
"grant_number": "2023/51/B/ST9/01921"
},
{
"grant_number": "2024/53/B/ST9/01154"
},
{
"grant_number": "80GSFC24M0006"
},
{
"grant_number": "80NSSC22K0645"
},
{
"grant_number": "80NSSC22K1011"
},
{
"grant_number": "80NSSC24K0908"
},
{
"grant_number": "80NSSC25K7687"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1007/s11214-025-01257-4",
"pmcid": "PMC12779750",
"primary_object": {
"basename": "s11214-025-01257-4.pdf",
"url": "https://authors.library.caltech.edu/records/n18ee-mqg16/files/s11214-025-01257-4.pdf"
},
"pub_year": "2026",
"author_list": "Cohen, C. M. S.; Alterman, B. L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mxpr2-ssr97",
"eprint_status": "archive",
"datestamp": "2026-02-03 15:28:02",
"lastmod": "2026-02-03 15:30:15",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Kozyra",
"given": "J. U."
},
"orcid": "0009-0006-0237-8527"
},
{
"name": {
"family": "Liemohn",
"given": "M. W."
},
"orcid": "0000-0002-7039-2631"
},
{
"name": {
"family": "Cattell",
"given": "C. A."
},
"orcid": "0000-0002-3805-320X"
},
{
"name": {
"family": "Dombeck",
"given": "J."
},
"orcid": "0000-0003-1635-3890"
},
{
"name": {
"family": "Escoubet",
"given": "C. P."
},
"orcid": "0000-0003-4475-6769"
},
{
"name": {
"family": "Thomsen",
"given": "M."
}
},
{
"name": {
"family": "Lu",
"given": "G."
},
"orcid": "0000-0001-5350-2889"
},
{
"name": {
"family": "Knipp",
"given": "D. J."
},
"orcid": "0000-0002-2047-5754"
},
{
"name": {
"family": "Paxton",
"given": "L. J."
},
"orcid": "0000-0002-2597-347X"
},
{
"name": {
"family": "Skoug",
"given": "R. M."
},
"orcid": "0000-0003-1991-2643"
},
{
"name": {
"family": "Elliott",
"given": "H. A."
},
"orcid": "0000-0003-2297-3922"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"name": {
"family": "Rastaetter",
"given": "L."
},
"orcid": "0000-0002-7343-4147"
},
{
"name": {
"family": "DeZeeuw",
"given": "D."
}
},
{
"name": {
"family": "Colpitts",
"given": "C."
},
"orcid": "0000-0001-7457-6537"
}
]
},
"title": "Multi-Species Energy-Banded Ions in the Ionosphere During the 21 January 2005 Magnetic Storm: Low-Altitude Edge of the Warm Plasma Cloak",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "warm plasma cloak; energy-banded ions; geomagnetic storms; subauroral ionosphere; inner magnetosphere; warm ions",
"note": "© 2026 Triad National Security LLC, and The Author(s). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
\n\n\n
The authors would like to thank the sources of funding for this study, which include M. Liemohn (NASA Grants 80NSSC19K0077 and 80NSSC21K1405). D. Knipp was partially supported by NASA Grant 80NSSC20K0199 and NSF award 1933040. A portion of this research was performed at NASA HQ. G. Lu was supported in part by the NASA LWS Program under award 80NSSC20K1784 and by the NASA HSR Program under award 80NSSC21K1673. The National Center for Atmospheric Research is a major facility sponsored by the National Science Foundation under Cooperative Agreement No. 1852977. The authors would also like to thank the Community Coordinated Modeling Centers (CCMC) and the University of Michigan CSEM team for supplying simulation outputs and assistance in visualization and analysis. The WDC, Kyoto University is acknowledged for Sym-H and ASY-H index data. We are grateful to M. Henderson for making available LANL MPA data for this event and D. J. McComas and D. Delapp for use of the ACE SWEPAM data. We thank A. F. Nagy, G. Rostoker, and B. Tsurutani for interesting and helpful discussions.
\n
\n
1. Defense Meteorological Satellite Program F16:
\n
Instruments on DMSP provide a range of ionospheric parameters, as well as the geomagnetic field, and, from DSMP F16 and beyond, optical emissions in the far and extreme ultraviolet. NASA CDAWeb is a repository for DMSP data.
Open Research: Data is publicly available. See DMSP NASA CDAWeb (
2025) in reference list.\n
2. Double Star (TC-1)
\n
Double Star TC-1 observes 3D ion distributions in the energy range 5 eV/q–32 keV/q without mass discrimination, electrons in the energy range 1 eV–25 keV, and wave magnetic fields at frequencies of 0–4 kHz in the inner magnetosphere.
Open Research: Data is publicly available. See Double Star TC-1 (
2025) in reference list.\n
3. Fast Auroral SnapshoT (FAST) mission:
\n
The Electrostatic Analyzer (ESA) (Carlson et al.,
2001) and the Time-of-flight Energy Angle Mass Spectrograph (TEAMS) (Klumpar et al.,
2001) instruments onboard the FAST satellite provided ion composition and ion and electron fluxes. The FAST data are used to understand the location, structure, and composition of the banded-in-energy ions in the ionosphere. The FAST SOC is the primary data collection and data archive processing facility for the Fast Auroral SnapshoT (FAST) mission. Open Research: Data is publicly available. See FAST Data Repository (
2025) in reference list.\n
4. Geomagnetic Indices:
\n
SYM-H, ASY-H, AE, AU, and AL are used to provide information on the level of geomagnetic activity. Data are archived at the NASA Goddard Space Flight Center, Space Physics Data Facility.
Open Research: Indices are publicly available. See OMNIweb Plus Repository (
2025) in the reference list.\n
5. Geostationary Operational Environmental Satellites (GOES10):
\n
GOES-10 carried a Space Environment Monitor (SEM), which included a Magnetometer (MAG), used in this study.
Open Research: The GOES data is publicly available. See GOES CDAWeb (
2025) in the reference list.\n
6. LANL/GEO
\n
The Magnetospheric Plasma Analyzer (MPA) on the Los Alamos National Labs geostationary satellites measures three-dimensional energy/charge distributions of both ions and electrons in the range of ∼1 eV/q to more than 40 KeV/q. For use at this orbit, the instrument was designed for high sensitivity with moderate energy and angular resolution.
Open Research: Datafiles are publicly available. See LANL GEO datafiles (
2025) in the reference list.\n
7. Solar Wind Electron Proton Alpha Monitor (SWEPAM) instrument on the Advanced Composition Explorer (ACE):
\n
During this event, the normal SWEPAM solar wind speed track mode with a 64 s cadence did not work owing to the presence of penetrating radiation and rapid changes in solar wind speed. However, the search mode was available in which the full energy range did work. These search mode observations have about a 3 min resolution and the energy range coverage spans from 260–17,900 eV/q with 10–12% energy resolution. The search mode solar parameters are determined by fitting Maxwellians to the distribution functions after removing any penetrating background radiation. This analysis technique is described in Skoug et al. (
2004).
Open Research: These data are publicly available. See ACE Science Center (
2025) in the reference list.\n
8. Solar wind parameters:
\n
Solar wind parameters at 1-min cadence (propagated to the Earth's bow shock) were used to explore solar wind driving of the energetics and dynamics of the energy banded soft ions. Data are archived at the NASA Goddard Space Flight Center, Space Physics Data Facility.
Open Research: Solar wind parameters are publicly available. See OMNIweb Plus Repository (
2025) in the reference list.\n
9. Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Global Ultraviolet Imager (GUVI):
\n
TIMED provides cross-track scanned images spanning 3,000 km in the cross-track direction of airglow and auroral features with 7 km spatial resolution at the nadir in the far ultraviolet, as well as inferred precipitating electron average energy and flux. The TIMED GUVI archive at the Johns Hopkins University Applied Physics Lab is the primary data collection and data processing facility for the TIMED/GUVI instrument.
Open Research: Data is publicly available. See TIMED/GUVI Images Repository (
2025) in the reference list.\n
10. Space Weather Modeling Framework including Magnetohydrodynamic Model (MHD) + Rice Convection Model (RCM) simulation:
\n
The outputs of the MHD + RCM simulation at a 10 min cadence in the magnetosphere and a 1 min cadence in the ionosphere were downloaded directly from the Community Coordinated Modeling Center's (CCMC's) model archive. The simulation was subsequently regenerated with a 1-min cadence in the magnetospheric output files to examine the rapid variations during the ICME sheath passage. The higher cadence magnetospheric outputs for the MHD + RCM run used in this study are available upon request from CCMC. Open Research: Model output and software information are publicly available. See CCMC Simulation Archive (2025) in the reference list.
",
"abstract": "\n
During the 21–22 January 2005 magnetic storm, the FAST satellite observed warm (< few keV) ions in discrete energy bands on the dayside at ∼3,000 km altitude for more than 6.5 hr. We suggest that the ionospheric energy-banded ions represent the low-altitude edge of the warm plasma cloak observed simultaneously by magnetospheric satellites. This is a clear example of the multi-species ion energy bands (10 eV to several keV) observed during strong magnetic storms by the FAST satellite, stretching from the diffuse auroral region to the plasmapause with lifetimes up to 12 hr. The close association of these energy-banded ions with magnetic storms, their broad latitudinal extent, and the presence of multiple ion species in the same energy band, rather than at the same velocity, indicate that this is a distinct phenomenon from other types of energy-banded ions. During the 21–22 January 2005 magnetic storm, the dayside ion energy band structures, centered at 10 eV (H+), 40 eV (H+ and He+), and 160 eV (H+, He+, and O+), were consistent with a “time-of-flight and velocity filter” formation process acting on a near-cusp, impulsive outflow of a <200 eV multi-species ion-source population, poleward and in the same hemisphere as FAST. Understanding the sources and dynamics of warm energy-banded ions and their linkage to the warm plasma cloak is important because during superstorms these ions are transported to L values as low as L ∼ 1.2 in the dawn sector, significantly altering the energetics of the mid-latitude ionosphere.
\n
© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nWe thank the referee for their useful comments that helped us improve the manuscript. This work makes use of Matplotlib (Hunter 2007), NumPy (Harris et al. 2020), and SciPy (Virtanen et al. 2020).
",
"abstract": "Recent intensive monitoring campaigns of active galactic nuclei have provided simultaneous X-ray, UV, and optical data of unprecedented quality. The observations revealed a strong correlation between the UV and optical variability, but a weaker correlation between the X-ray and UV bands. This challenges the standard X-ray reprocessing scenario. We revisit the X-ray/UV connection in NGC 5548 by fitting archival 2014 HST and Swift /XRT light curves assuming X-ray reverberation from a dynamically evolving X-ray corona. Our results show that as long as the corona height, photon index, and power vary over time, X-ray reverberation can explain the observed UV and optical variability within 2% and 5%, respectively (on average). The evolution of the best-fit parameters suggests that fast changes in coronal geometry and energetics on a timescale of days are required to explain the observed variability.
",
"date": "2026-01",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "705",
"publisher": "EDP Sciences",
"pagerange": "A257",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/pwjm2-1zx18",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1051/0004-6361/202557643",
"primary_object": {
"basename": "aa57643-25.pdf",
"url": "https://authors.library.caltech.edu/records/pwjm2-1zx18/files/aa57643-25.pdf"
},
"pub_year": "2026",
"author_list": "Papoutsis, M.; Papadakis, I. E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9n6n4-7da46",
"eprint_status": "archive",
"datestamp": "2025-12-22 23:02:51",
"lastmod": "2025-12-22 23:02:51",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Brenneman",
"given": "Laura W."
},
"orcid": "0000-0003-2663-1954"
},
{
"name": {
"family": "Wilkins",
"given": "Daniel R."
},
"orcid": "0000-0002-4794-5998"
},
{
"name": {
"family": "Ogorza\u0142ek",
"given": "Anna"
},
"orcid": "0000-0003-4504-2557"
},
{
"name": {
"family": "Rogantini",
"given": "Daniele"
},
"orcid": "0000-0002-0786-7307"
},
{
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Jur\u00e1\u0148ov\u00e1",
"given": "Anna"
},
"orcid": "0000-0002-7292-6852"
},
{
"name": {
"family": "Mizumoto",
"given": "Misaki"
},
"orcid": "0000-0003-2161-0361"
},
{
"name": {
"family": "Noda",
"given": "Hirofumi"
},
"orcid": "0000-0001-6020-517X"
},
{
"name": {
"family": "Behar",
"given": "Ehud"
},
"orcid": "0000-0001-9735-4873"
},
{
"name": {
"family": "Boissay-Malaquin",
"given": "Rozenn"
},
"orcid": "0000-0003-2704-599X"
},
{
"name": {
"family": "Guainazzi",
"given": "Matteo"
},
"orcid": "0000-0002-1094-3147"
},
{
"name": {
"family": "Okajima",
"given": "Takashi"
},
"orcid": "0000-0002-6054-3432"
},
{
"name": {
"family": "Hoffman",
"given": "Erika"
},
"orcid": "0000-0003-3496-8928"
},
{
"name": {
"family": "Keshet",
"given": "Noa"
},
"orcid": "0000-0003-2535-6436"
},
{
"name": {
"family": "Kaastra",
"given": "Jelle"
},
"orcid": "0000-0001-5540-2822"
},
{
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"name": {
"family": "Yamauchi",
"given": "Makoto"
},
"orcid": "0000-0003-1100-1423"
}
]
},
"title": "A Sharper View of the X-Ray Spectrum of MCG\u20136-30-15 with XRISM, XMM-Newton, and NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; High energy astrophysics; Black hole physics; Accretion",
"note": "© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
We thank both the anonymous referee and Richard Mushotzky for insightful and constructive reviews that improved this manuscript. We thank Tahir Yaqoob for helpful advice in navigating the XRISM data reduction during a changing calibration landscape. We are grateful to the directors and scheduling and operations teams of XMM-Newton and NuSTAR for coordinated observations that greatly enhance the scientific return of these XRISM data. L.B. thanks Andy Young for stimulating conversations on the Chandra/HETG data, and gratefully acknowledges funding support from NASA under grant No. 80NSSC24K0684. M.M. acknowledges support from JSPS KAKENHI grant No. JP21K13958 and Yamada Science Foundation. This paper employs a list of Chandra data sets, obtained by the Chandra X-ray Observatory, contained in the Chandra Data Collection (CDC) ADS/Sa.CXO#obs/04759, ADS/Sa.CXO#obs/04760, ADS/Sa.CXO#obs/04761, ADS/Sa.CXO#obs/04762.
\n
\n
\n
We present a time-averaged spectral analysis of the 2024 XRISM observation of the narrow-line Seyfert-1 galaxy MCG–6-30-15, taken contemporaneously with XMM-Newton and NuSTAR. Our analysis leverages a unique combination of broadband and high-resolution X-ray spectroscopy to definitively isolate and characterize both broad and narrow emission and absorption features in this source. The best-fitting model for the joint spectral analysis is very well described by reflection from the inner accretion disk illuminated by a compact corona, modified by multizone ionized absorption from an outflowing wind along the line of sight. The XRISM/Resolve data confirm that a strong, relativistically broadened Fe Kα emission line is required in order to obtain an adequate model fit. The Resolve data additionally verify the presence of a vout ∼ 2300 km s−1 component of this outflowing wind, find tentative evidence for a vout ∼ 20,000 km s−1 wind component, and indicate that the reflection from distant, neutral material may originate in a nonuniform structure rather than the traditional torus of AGN unification schemes. Though a rapid prograde black hole spin is statistically preferred by the best-fitting model, consistent with previous results, the AGN flux variability over the course of the observation complicates the interpretation of the time-averaged spectra. This insight, clarified by the combination of high signal-to-noise and high spectral resolution in the joint data set, emphasizes the importance of time-resolved, high-resolution spectral analysis in unambiguously measuring the physical properties of variable AGN.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe are grateful to the anonymous referee and to the editor, Allen W. Shafter, for the careful reading of and useful comments on the manuscript. Y.H. is deeply grateful to Prof. Giovanna Tinetti for her valuable support and the insightful suggestions that significantly improved the discussion section. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration (NASA). We thank the NuSTAR Operations, Software, and Calibration teams for their support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software, jointly developed by the ASI Science Data Center (Italy) and the California Institute of Technology (USA). It also utilized data and software provided by the High Energy Astrophysics Science Archive Research Center, a service of the Astrophysics Science Division at NASA’s Goddard Space Flight Center. This work also made use of data provided by NASA through the Swift mission. We thank Dr. James Delaunay, Dr. Kim Page, and the Swift Observatory Duty Scientist for their assistance in coordinating observations with NuSTAR. We also acknowledge the use of data from the Einstein Probe (EP) mission and sincerely thank the EP mission team for supporting our analysis. We are especially grateful to the coordinators and schedulers from Einstein Probe, NuSTAR, and Swift for their generous help in planning and executing the joint observations. We gratefully acknowledge the Principal Investigators of EP, NuSTAR, and Swift for approving our DDT and ToO requests. This project was supported by the Caltech SURF program and NASA grants FAH.NUSBCD-1-NASA.NS. Yuk L. Yung was supported by NASA Grant P2794428 to Caltech.
\n\nNuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift - Swift Gamma-Ray Burst Mission, EP. -
\n\nXSPEC (K. A. Arnaud 1996), HEASoft, Python.
",
"abstract": "\n
Stellar flares are potent drivers of atmospheric evolution on orbiting exoplanets, primarily through extreme ultraviolet (EUV) and soft X-ray irradiation. However, the contribution of hard X-rays (HXR; 3–20 keV), which penetrate deeper into planetary atmospheres, to mass loss and particle acceleration has remained poorly understood. To quantify the HXR share of the total radiative budget, we conducted quasi-simultaneous observations of the active M-dwarf AU Mic using NuSTAR, Swift, and the Einstein Probe. Our analysis detected two major flares, and we performed an empirical check by deriving a quiescent-phase soft X-ray (SXR; 0.3–3 keV) to HXR relation and then applying it to the flares. By combining this with the quiescent coronal SXR–EUV relation conversion of J. Sanz-Forcada et al, we computed the total high-energy flux (EUV + SXR + HXR) and assessed the relative role of HXR in atmospheric escape. We find that HXR accounts for only a few percent of the total radiative energy budget during both quiescent and flaring states. While a high-energy spectral tail is detected in the second flare, time-resolved spectroscopy reveals a dominant chromospheric-evaporation signature, indicating that the flare energetics are primarily thermal.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors thank the anonymous referee for comments that improved the clarity of the manuscript. This work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. G.M. acknowledges financial support from the European Union’s Horizon Europe research and innovation program under the Marie Sk\u0142odowska-Curie grant agreement No. 101107057. A.I. acknowledges support from the Royal Society. J.B.C. is supported under 80GSFC21M0006. T.D. acknowledges support from the DFG research unit FOR 5195 (grant No. WI 1860/20-1). The research of E.N. is supported by an appointment to the NASA Postdoctoral Program at the NASA Goddard Space Flight Center, administered by Oak Ridge Associated Universities under contract with NASA. M.P. acknowledges support from the JSPS Postdoctoral Fellowship for Research in Japan, grant No. P24712, as well as the JSPS Grants-in-Aid for Scientific Research—KAKENHI, grant No. J24KF0244.
\n\nNuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission.
\n\nXSPEC (K. A. Arnaud 1996), XSTAR (T. Kallman & M. Bautista 2001), relxill (T. Dauser et al. 2014; J. García et al. 2014).
",
"abstract": "\n
IGR J17091−3624 is the only black hole X-ray binary candidate—aside from the well-studied black hole system GRS 1915+105—observed to exhibit a wide range of structured variability patterns in its light curves. In 2025, the source underwent a “failed” outburst: it brightened in the hard state but did not transition to the soft state before returning to quiescence within a few weeks. During this period, IGR J17091−3624 was observed by multiple ground- and space-based facilities. Here, we present results from six pointed NuSTAR observations obtained during the outburst. None of the NuSTAR light curves showed the exotic variability classes typical of the soft state in this source; however, we detected, for the first time, strong dips in the count rate during one epoch, with a total duration of ∼4 ks as seen by NuSTAR. Through spectral and timing analysis of all six epochs, we investigate the hard-state spectral evolution and the nature of the dips. A clear evolution of the coronal properties with luminosity is observed over all six epochs, with clear signatures of relativistic disk reflection that remain largely unchanged across the first five epochs. The first five epochs also show a strong and stable quasiperiodic oscillation feature in the power spectra. The dips observed in Epoch 5 are consistent with partial obscuration by ionized material with a column density NH ≈ 2.0 × 1023 cm−2. We discuss possible origins for this material and place constraints on the orbital parameters and distance of the system.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors thank the referee for valuable comments that improved the quality of this paper. R.S. acknowledges funding from the CAS-ANID grant No. CAS220016. R.S. and F.N. acknowledge financial support from INAF-PRIN grant “A Systematic Study of the largest reservoir of baryons and metals in the Universe: the circumgalactic medium of galaxies” (No. 1.05.01.85.10). F.N., F.C., and E.P. acknowledge financial support from PRIN-MUR-2022 grant “Advanced X-ray modeling of black hole winds” (DRAGON; No. PRIN 2022K9N5B4). Y.K. acknowledges support from DGAPA-PAPIIT grant IN102023. L.P., F.N., and A.L. acknowledge financial support from EU HORIZON-2020 grant “AHEAD2020” (Agreement No. 871158). L.P. and F.N. acknowledge support by ASI (Italian Space Agency) through the Contract No. 2019-27-HH.0 on Athena.
\nThe research is partly based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This research has made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. This research has made use of the NuSTAR Data Analysis Software (NUSTARDAS), jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (Caltech, USA).
",
"abstract": "We present a high-resolution X-ray spectroscopic study of the narrow-line Seyfert 1 galaxy NGC 4051 using two XMM-Newton high-resolution Reflection Grating Spectrometer observations. The spectra reveal three distinct layers of photoionized gas flowing outward from the central black hole: a low-ionization phase (LIP), a higher-ionization phase (HIP), and a high-velocity and high-ionization phase (HVIP). Each absorber leaves characteristic imprints on the soft X-ray spectrum. While the LIP and HVIP are fully consistent with being in ionization equilibrium with the central radiation field over the course of the ∼250 ks spanned by the two observations, the HIP shows a significant change in ionization (3.8σ), suggesting nonequilibrium. By modeling the two spectra with our time-dependent photoionization code ( TEPID ), we constrain the density of the HIP gas to log nH = 7.7_(−0.9)^(+0.2) and estimate its distance to be about R = 0.45_(−0.09)^(+0.80) lt-day from the black hole, corresponding to R = 4000(−800)^(+7000) gravitational radii. In contrast, the narrow soft X-ray emission lines remain constant, consistent with an origin in the more extended narrow-line region. Our results show the value of combining high-resolution and time-resolved spectroscopy to probe the structure, physical conditions, and variability of active galactic nucleus outflows.
",
"date": "2025-12-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "995",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "6",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/v0jjz-ke547",
"funders": {
"items": [
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo",
"grant_number": "CAS220016"
},
{
"grant_number": "1.05.01.85.10"
},
{
"grant_number": "PRIN 2022K9N5B4"
},
{
"grant_number": "IN102023"
},
{
"grant_number": "871158"
},
{
"grant_number": "2019-27-HH.0"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/ae1614",
"primary_object": {
"basename": "Serafinelli_2025_ApJ_995_6.pdf",
"url": "https://authors.library.caltech.edu/records/v0jjz-ke547/files/Serafinelli_2025_ApJ_995_6.pdf"
},
"pub_year": "2025",
"author_list": "Serafinelli, Roberto; Nicastro, Fabrizio; et al."
},
{
"id": "https://authors.library.caltech.edu/records/g86bv-71g46",
"eprint_status": "archive",
"datestamp": "2025-12-11 22:26:39",
"lastmod": "2025-12-11 22:26:39",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Wi\u015bniewska",
"given": "A."
},
"orcid": "0000-0001-9037-5938"
},
{
"name": {
"family": "Ichimoto",
"given": "K."
},
"orcid": "0000-0001-8689-3564"
},
{
"name": {
"family": "Koza",
"given": "J."
},
"orcid": "0000-0002-7444-7046"
},
{
"name": {
"family": "Kontogiannis",
"given": "I."
},
"orcid": "0000-0002-3694-4527"
},
{
"name": {
"family": "Pietrow",
"given": "A. G. M."
},
"orcid": "0000-0002-0484-7634"
},
{
"id": "Muro-Gabriel-D",
"name": {
"family": "Muro",
"given": "G. D."
},
"orcid": "0000-0003-0581-1278"
},
{
"name": {
"family": "G\u00f6m\u00f6ry",
"given": "P."
},
"orcid": "0000-0002-0473-4103"
}
]
},
"title": "Wave Period Variability in a Quiescent Solar Prominence",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active sun; Solar atmosphere; Helioseismology; Solar oscillations; Solar filaments; Solar prominences; Wavelet analysis",
"note": "© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nA.W., J.K., and P.G. acknowledge the project VEGA 2/0043/24. A.P. is supported by the Deutsche Forschungsgemeinschaft (DFG), project number PI 2102/1-1. The authors thank the staff members of Hida Observatory for supporting our observation and continuous operation of the SMART telescope. The spectropolarimeters on the Domeless Solar Telescope and SDDI were constructed with the support of MEXT/JSPS KAKENHI grant Nos. 22244013 (PI: K.I.) and JP15H05814 (PI: K.I.), respectively. We thank the Solar Orbiter and STEREO teams for making the data publicly available.
\n\nSDO - Solar Dynamics Observatory (AIA), SO - (EUI/FSI), STEREO - NASA's Solar Terrestrial Relations Observatory(EUVI), SolO (EUI/FSI).
",
"abstract": "\n
On 2022 September 26, we observed a quiescent solar prominence with Hα imaging spectroscopy using the Solar Dynamics Doppler Imager (SDDI) on board the Solar Magnetic Activity Research Telescope (SMART). Unlike earlier works that detected 4 and 15 minute oscillations through long-slit, 1D wavelet methods, we adapt the wavelet analysis to 3D data to explore the full prominence structure. Complementary data from Solar Dynamics Observatory/Atmospheric Imaging Assembly (304, 171 Å) STEREO-A Extreme Ultraviolet Imager (EUVI; 304 Å), and Solar Orbiter Extreme Ultraviolet Imager/Full Sun Imager (304, 174 Å) enable a multiview, multithermal investigation of wave periodicity across the prominence. Our aim is to characterize how oscillatory periods are distributed in plasma at different temperatures and viewing angles, thereby assessing wave propagation and variability throughout the prominence body. We analyze time series of Doppler signal from SMART/SDDI Hα observations alongside extreme-ultraviolet intensity variations from space-based instruments. We detect oscillatory plasma motions with periods spanning 3–74 minutes. Strong periodicity at 20, 31, and 53 minutes dominates in neutral plasma (Hα), while 13 and 74 minute oscillations are pronounced in the 304 Å passband, concentrated mainly in the central prominence. Additional short-period fluctuations include weaker 3–6 minute oscillations and rapid 30 s transverse waves in Doppler signals near the solar surface. These findings highlight the richness of wave periodicity in quiescent prominences, revealing a dynamic superposition of long- and short-period oscillations and kink-like disturbances. This multi-instrument, 3D perspective advances our understanding of how prominence plasma supports and modulates diverse wave modes.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
This work was supported in part by the NASA LWS Strategic Capabilities project at the University of Michigan under NASA grant 80NSSC22K0892 (SCEPTER) and NASA SWxC grant 80NSSC23M0191 (CLEAR). L.Z. acknowledges NASA LWS grant 80NSSC21K0417, NASA R2O2R grant 80NSSC22K0269, NASA HSR grant 80NSSC23K0091, and NSF ANSWERS grant GEO-2149771. N.S. acknowledges NASA LWS grant 80NSSC24K1104, NSF Solar Terrestrial grant 2323303, and NASA R2O2R grant 80NSSC23K0450. A.K. acknowledges financial support from NASA’s NNN06AA01C (Parker Solar Probe EPI-Lo) contract and NASA LWS grant 80NSSC25K0130. Parker Solar Probe was designed and built and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We acknowledge the PSP/IS\u2299IS team (PI: David McComas, Princeton University) and the PSP/FIELDS team (PI: Stuart D. Bale, UC Berkeley) for use of data. We acknowledge the EPD and magnetic field data from Solar Orbiter, generated and maintained by the EPD team and magnetometer team on the Solar Orbiter Archive (SOAR). This work utilizes data produced collaboratively between AFRL/ADAPT and NSO/NISP. We thank the referee for helpful comments. Resources supporting this work were provided in part by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. The authors acknowledge the Texas Advanced Computing Center (TACC) at the University of Texas at Austin for providing HPC resources that have contributed to the research results reported in this paper.
\n
\n
",
"abstract": "\n
On 2022 September 5, a large solar energetic particle (SEP) event was detected by Parker Solar Probe (PSP) and Solar Orbiter (SolO) at heliocentric distances of 0.07 and 0.71 au, respectively. PSP observed an unusual velocity dispersion signature: particles below ∼1 MeV exhibited a normal velocity dispersion, while higher-energy particles displayed an inverse velocity arrival (IVA) feature, with the most energetic particles arriving later than those at lower energies. The maximum energy increased from about 20–30 MeV upstream to over 60 MeV downstream of the shock. The arrival of SEPs at PSP was significantly delayed relative to the expected onset of the eruption. In contrast, SolO detected a typical large SEP event characterized by a regular velocity dispersion at all energies up to 100 MeV. To understand these features, we simulate particle acceleration and transport from the shock to the observers with our newly developed SEP model—Particle ARizona and MIchigan Solver on Advected Nodes. Our results reveal that the IVA and delayed particle onset detected by PSP originate from the time-dependent diffusive shock acceleration processes. After shock passage, PSP’s magnetic connectivity gradually shifted due to its high velocity near perihelion, detecting high-energy SEPs streaming sunward. Conversely, SolO maintained a stable magnetic connection to the strong shock region where efficient acceleration was achieved. These results underscore the importance of spatial and temporal dependence in SEP acceleration at interplanetary shocks and provide new insights to understand SEP variations in the inner heliosphere.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
We thank the anonymous referee for the valuable comments and suggestions, which greatly improved the manuscript. We acknowledge the use of data from the Solar Orbiter, Wind, CHASE, SDO, and SOHO spacecraft. This work is supported by NSFC under grant 12333009 and by the Fundamental Research Funds for the Central Universities under grant KG202506. Solar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. Solar Orbiter SWA work at UCL/MSSL is currently funded under UKRI and UKSA grants UKRI1204, ST/W001004/1, and UKRI1919.
\n
\n
Local particle acceleration in the shock sheath region formed during the interaction between multiple coronal mass ejections (CMEs) is a complicated process that is still under investigation. On 2024 March 23, the successive eruption of two magnetic flux ropes from the solar active region 3614 produced twin CMEs, as identified in coronagraph images. By analyzing in situ data from Solar Orbiter and Wind, it is found that the primary interplanetary CME (ICME)-driven shock overtook the preceding ICME, trapping it in the sheath between the shock and the primary ICME, forming the ICME-in-sheath (IIS) structure. Using Solar Orbiter observations, we show that both electrons and ions are accelerated within the IIS. A clear enhancement of suprathermal electrons was observed at the IIS boundary, where strong flow shear and large magnetic field variation suggest possible local electron acceleration. Electrons (>38 keV) exhibit a long-lasting enhancement in the IIS with a spectral index of ∼2.2, similar to that in the shock sheath and the primary ICME, indicating a similar solar origin. Inside both the sheath and IIS, spectra of protons and 4He are generally consistent with the prediction of the diffusive shock acceleration, whereas Fe and O present a double power-law shape. Additionally, the Fe/O ratio in the IIS is higher than that in the sheath, and closer to the abundance of the flare-related particles, suggesting the remnant particles of flare confined in the IIS.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
We thank the IS\u2299IS team and everyone that made the PSP mission possible. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/PSP. PSP was designed and built and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). F.F. was partially supported by NASA award 80NSSC21K1766. D.R. was partially supported by Thailand’s National Science and Technology Development Agency (NSTDA) and the National Research Council of Thailand (NRCT) under the High-Potential Research Team Grant Program (N42A650868). M.A.D. is supported by NASA award 80NSSC25K7687. This work was partially supported by a subcontract at University of Delaware (SUB0000165) under the LWS program (NNN06AA01C).
\n
\n
\n
It has been inferred from theory that the spatial diffusion coefficient (κ) upstream of shocks is anticorrelated with the intensity of solar energetic particles (SEPs) at the shock (jshock) motivated by quasi-linear theory (QLT). This is because a lower κ along the magnetic field (κ\u2225) implies that particles are trapped for longer, providing more acceleration and resulting in a higher jshock. However, the simplest version of DSA predicts that jshock is determined by the source of the injected population at the shock and plasma density jump with no relation to κ for low-energy SEPs. Here, we identify the relationship between κ and jshock, whose form is unknown, using Parker Solar Probe observations of eight shocks within 1 au. We estimate a characteristic κfit along the shock normal by fitting the upstream SEP intensity profiles with a 1D steady-state transport model for acceleration and escape assuming pitch-angle isotropy in the plasma frame. Also, we estimate κ\u2225 based on the magnetic power spectral density using QLT for comparison with κfit. Our results show that both quantities are anticorrelated with jshock. Instead of a uniform relationship between κ and jshock, we find distinct relationships appearing as potential power laws manifested across SEP events with no obvious radial dependence from 0.07 to 0.74 au. These relationships may be grouped by similar shock parameters (in terms of speed, strength, and orientation). Our findings raise questions about SEP transport and its radial dependence within 1 au and provide important observational constraints for models of shock-accelerated particles.
\n
© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the anonymous referee for feedback. This Letter makes use of the following ALMA data: ADS/JAO.ALMA#2024.A.00003.T and ADS/JAO.ALMA#2024.A.00009.T. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The Allen Telescope Array refurbishment program and its ongoing operations are being substantially funded through the Franklin Antonio Bequest. Additional contributions from Frank Levinson, Greg Papadopoulos, the Breakthrough Listen Initiative, and other private donors have been instrumental in the renewal of the ATA. Breakthrough Listen is managed by the Breakthrough Initiatives, sponsored by the Breakthrough Prize Foundation. The Paul G. Allen Family Foundation provided major support for the design and construction of the ATA, alongside contributions from Nathan Myhrvold, Xilinx Corporation, Sun Microsystems, and other private donors. The ATA has also been supported by contributions from the US Naval Observatory and the US National Science Foundation. We thank the GMRT staff for making these observations possible. The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (Caltech, USA). This research has made use of data obtained from the Chandra Data Archive provided by the Chandra X-ray Center (CXC). This Letter employs a list of Chandra data sets, obtained by the Chandra X-ray Observatory, contained in the Chandra Data Collection doi:10.25574/cdc.463. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research has made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
\nR.M. acknowledges support by the National Science Foundation under award No. AST-2224255 and by NASA under grants 80NSSC22K1587, 80NSSC25K7591, and 80NSSC22K0898. G.M. acknowledges financial support from the INAF mini-grant “The high-energy view of jets and transient” (Bando Ricerca Fondamentale INAF 2022). B.D.M. acknowledges support from NASA AAG (grant No. 80NSSC22K0807), the Fermi Guest Investigator Program (grant No. 80NSSC24K0408), and the Simons Foundation (grant No. 727700). The Flatiron Institute is supported by the Simons Foundation. D.T. is supported by the Sherman Fairchild Postdoctoral Fellowship at Caltech. F.D.C. acknowledges support from the DGAPA/PAPIIT grant IN113424. D.L.C. acknowledges support from the Science and Technology Facilities Council (STFC) grant ST/X001121/1. N.L. thanks the LSST-DA Data Science Fellowship Program, which is funded by LSST-DA, the Brinson Foundation, the WoodNext Foundation, and the Research Corporation for Science Advancement Foundation; her participation in the program has benefited this work. C.T.C. and K.D.A. gratefully acknowledge support from NSF under grant AST-2307668 and from the Alfred P. Sloan Foundation.
\n\nSwift - Swift Gamma-Ray Burst Mission (XRT and UVOT), AAVSO - American Association of Variable Star Observers International Database, CTIO:1.3m - Cerro Tololo Inter-American Observatory's 1.3 meter Telescope, CTIO:1.5m - Cerro Tololo Inter-American Observatory's 1.5 meter Telescope, CXO - Chandra X-ray Observatory satellite.
\n\nastropy (Astropy Collaboration et al. 2013,2018, 2022).
",
"abstract": "We present X-ray (0.3–79 keV) and radio (0.25–203 GHz) observations of the most luminous fast blue optical transient (LFBOT) AT 2024wpp at z = 0.0868, spanning 2–280 days after first light. AT 2024wpp shows luminous (LX ≈ 1.5 × 1043 erg s−1), variable X-ray emission with a Compton hump peaking at δt ≈ 50 days. The X-ray spectrum evolves from a soft (Fν ∝ ν−0.6) to an extremely hard state (Fν ∝ ν1.26) accompanied by a rebrightening at δt ≈ 50 days. The X-ray emission properties favor an embedded high-energy source shining through asymmetric expanding ejecta. We detect radio emission peaking at L9 GHz ≈ 1.7 × 1029 erg s−1 Hz−1 at δt ≈ 73 days. The spectral evolution is unprecedented: the early millimeter fluxes rise nearly an order of magnitude during δt ≈ 17–32 days, followed by a decline in spectral peak fluxes. We model the radio emission as synchrotron radiation from an expanding blast wave interacting with a dense environment (M \u0307∼10−³ M\u2299 yr−1 for vw = 1000 km s−1). The inferred outflow velocities increase from Γβc ≈ 0.07c to 0.42c during δt ≈ 32–73 days, indicating an accelerating blast wave. We interpret these observations as a shock propagating through a dense shell of radius ≈1016 cm and then accelerating into a steep density profile ρCSM(r) ∝ r−3.1. All radio-bright LFBOTs exhibit similar circumstellar medium (CSM) density profiles (ρCSM ∝ r−3), suggesting similar progenitor processes. The X-ray and radio properties favor a progenitor involving super-Eddington accretion onto a compact object launching mildly relativistic disk wind outflows.
",
"date": "2025-11-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "993",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "L6",
"issn": "2041-8205",
"official_url": "https://authors.library.caltech.edu/records/y7ery-5ge55",
"funders": {
"items": [
{},
{
"grant_number": "AST-2224255"
},
{
"grant_number": "80NSSC22K1587"
},
{
"grant_number": "80NSSC25K7591"
},
{
"grant_number": "80NSSC22K0898"
},
{},
{
"grant_number": "80NSSC22K0807"
},
{
"grant_number": "80NSSC24K0408"
},
{
"grant_number": "727700"
},
{},
{
"grant_number": "IN113424"
},
{
"grant_number": "ST/X001121/1"
},
{
"grant_number": "-"
},
{},
{},
{
"grant_number": "AST-2307668"
},
{}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "TAPIR"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/2041-8213/ae0b4d",
"primary_object": {
"basename": "A._J._2025_ApJL_993_L6.pdf",
"url": "https://authors.library.caltech.edu/records/y7ery-5ge55/files/A._J._2025_ApJL_993_L6.pdf"
},
"pub_year": "2025",
"author_list": "A. J., Nayana; Margutti, Raffaella; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ycxkr-2tn85",
"eprint_status": "archive",
"datestamp": "2025-11-04 16:05:14",
"lastmod": "2026-03-10 00:33:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"name": {
"family": "Moskalenko",
"given": "I. V."
},
"orcid": "0000-0001-6141-458X"
},
{
"name": {
"family": "Heikkila",
"given": "B. C."
}
},
{
"name": {
"family": "J\u00f3hannesson",
"given": "G."
},
"orcid": "0000-0003-1458-7036"
},
{
"name": {
"family": "Porter",
"given": "T. A."
},
"orcid": "0000-0002-2621-4440"
}
]
},
"title": "Voyager 1 Observations of Galactic Cosmic-Ray Isotopes in the Very Local Interstellar Medium: Evidence for Primary \u00b2H and B",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galactic cosmic rays; Interstellar medium",
"note": "© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
Edward Stone would have been a coauthor on this paper, but he passed away on 2024 June 9. He was a long time friend and colleague to us and will be greatly missed. We thank him for all his contributions to not only this paper but to space science itself. We thank Paola Caselli, Katharina Lodders, Alexei Ivlev, and Alberto Ribon for fruitful discussions, and Stefano Della Torre for assistance with GalProp-HelMod-derived VLISM and modulated spectra. A.C.C. and B.C.H. acknowledge Voyager data analysis support from NASA award No. 80NM0018F0577. I.V.M. and T.A.P. acknowledge support from NASA grant Nos. 80NSSC23K0169, 80NSSC22K0718, and 80NSSC22K0477.
\n
\n
We present the first measurements of the energy spectra of the isotopes of Galactic cosmic rays (GCRs) with nuclear charge Z = 1–14 in the very local interstellar medium (VLISM). We also update our previously published energy spectra of GCR elements in the VLISM from Z = 1–28 for a new longer time period of observations, 2013 January 1 through 2021 December 31. The observations are from the Cosmic Ray Subsystem on the Voyager 1 (V1) spacecraft and cover the Z-dependent energy range from ∼3 to 661 MeV nuc−1. The data are fit to eight models using the GCR propagation code GalProp, which differ by having four options for fragmentation and two options for production cross sections. The models are all plain diffusion models with injection spectra as power laws in rigidity, where the propagation parameters and the injection power-law index are the same for all species, and derived self-consistently and independently for each model. The VLISM energy spectra generated by the models agree reasonably well with the observed VLISM energy spectra for the elements with Z = 1–28 and with the isotopes with Z = 1–14. However, to achieve reasonable fits to the 2H and B energy spectra, it was necessary to add a primary source of 2H and B.
\n
© The Author(s) 2025. Published by Oxford University Press on behalf of Royal Astronomical Society.
\n\n
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
\n
The authors would like to thank the reviewer for their helpful feedback, which helped to improve the final version of the manuscript. DJW, TPR, and WNA acknowledge support from the Science and Technology Facilities Council (STFC; grant codes ST/Y001060/1, ST/X001075/1, andST/Y001982/1, respectively). PK acknowledges support from the National Aeronautics and Space Administration (NASA) through the NASA Hubble Fellowship grant HST-HF2-51534.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. CP is supported by PRIN MUR SEAWIND–European Union–NextGenerationEU. RS acknowledges support from the University of the Chinese Academy of Sciences during part of this work, as well as support from the Italian National Institute for Astrophysics (INAF) grant number 1.05.23.04.04. This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the nustardas software package, jointly developed by the ASDC (Italy) and Caltech (USA). This research has also made use of data obtained with XMM–Newton, a European Space Agency (ESA) science mission with instruments and contributions directly funded by ESA Member States.
\n\nThe raw observational data underlying this article are all publicly available from ESA’s XMM–Newton Science Archive6 and NASA’s HEASARC archive.7
",
"abstract": "We present a series of five new broadband X-ray observations of the ultraluminous X-ray source Holmberg IX X-1, performed by XMM-Newton and NuSTAR in coordination. The first three of these show high soft X-ray fluxes but a near total collapse of the high-energy (\u227315 keV) emission, previously seen to be surprisingly stable across all prior broadband observations of the source. The latter two show a recovery in hard X-rays, remarkably once again respecting the same stable high-energy flux exhibited by all of the archival observations. We also present a joint analysis of all broadband observations of Holmberg IX X-1 to date (encompassing 11 epochs in total) in order to investigate whether it shows the same luminosity–temperature behaviour as NGC 1313 X-1 (which also shows a stable high-energy flux), whereby the hotter disc component in the spectrum exhibits two distinct, positively-correlated tracks in the luminosity–temperature plane. Holmberg IX X-1 may show similar behaviour, but the results depend on whether the highest energy emission is assumed to be an up-scattering corona or an accretion column. The strongest evidence for this behaviour is found in the former case, while in the latter the new 'soft' epochs appear distinct from the other high-flux epochs. We discuss possible explanations for these new 'soft' spectra in the context of the expected structure of super-Eddington accretion flows around black holes and neutron stars, and highlight a potentially interesting analogy with the recent destruction and re-creation of the corona seen in the AGN 1ES 1927+654.
",
"date": "2025-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "543",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "2902-2916",
"issn": "0035-8711",
"official_url": "https://authors.library.caltech.edu/records/ytwtq-12z76",
"funders": {
"items": [
{
"grant_number": "ST/Y001060/1"
},
{
"grant_number": "ST/X001075/1"
},
{
"grant_number": "ST/Y001982/1"
},
{
"grant_number": "HST-HF2-51534.001-A"
},
{},
{
"grant_number": "NAS5-26555"
},
{},
{},
{
"grant_number": "1.05.23.04.04"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.1093/mnras/staf1609",
"primary_object": {
"basename": "staf1609.pdf",
"url": "https://authors.library.caltech.edu/records/ytwtq-12z76/files/staf1609.pdf"
},
"pub_year": "2025",
"author_list": "Walton, D. J.; Bachetti, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9k91n-qc820",
"eprint_status": "archive",
"datestamp": "2025-11-04 19:53:43",
"lastmod": "2025-11-04 19:53:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Ruz",
"given": "J."
},
"orcid": "0000-0002-3253-7027"
},
{
"name": {
"family": "Todarello",
"given": "E."
}
},
{
"name": {
"family": "Vogel",
"given": "J.\u2009K."
},
"orcid": "0000-0002-5850-5517"
},
{
"name": {
"family": "Cand\u00f3n",
"given": "F.\u2009R."
}
},
{
"name": {
"family": "Giannotti",
"given": "M."
},
"orcid": "0000-0001-9823-6262"
},
{
"id": "Grefenstette-Brian",
"name": {
"family": "Grefenstette",
"given": "B."
},
"orcid": "0000-0002-1984-2932"
},
{
"name": {
"family": "Hudson",
"given": "H.\u2009S."
},
"orcid": "0000-0001-5685-1283"
},
{
"name": {
"family": "Hannah",
"given": "I.\u2009G."
},
"orcid": "0000-0003-1193-8603"
},
{
"name": {
"family": "Irastorza",
"given": "I.\u2009G."
},
"orcid": "0000-0003-1163-1687"
},
{
"name": {
"family": "Kim",
"given": "C.\u2009S."
},
"orcid": "0000-0002-5683-5950"
},
{
"name": {
"family": "Regis",
"given": "M."
},
"orcid": "0000-0003-0399-0284"
},
{
"name": {
"family": "Smith",
"given": "D.\u2009M."
},
"orcid": "0000-0002-0542-5759"
},
{
"name": {
"family": "Taoso",
"given": "M."
},
"orcid": "0000-0001-7181-2071"
},
{
"name": {
"family": "Trujillo Bueno",
"given": "J."
},
"orcid": "0000-0001-5131-4139"
}
]
},
"title": "NuSTAR as an Axion Helioscope",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Axions; Cosmology; Particle astrophysics; Particle dark matter",
"note": "Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
\n\n\n
\n
\n
We gratefully acknowledge the support of the NuSTAR operations, software, and calibration teams in the execution and analysis of these observations. Our thanks also extend to Georg G. Raffelt, Ji\u0159í Št\u011bpan, and T. O’Shea for insightful discussions. E. T., M. R., and M. T. are supported by the project “Theoretical Astroparticle Physics (TAsP)” funded by INFN and the “Grant for Internationalization” from the University of Torino. M. T. further acknowledges the research grant “Addressing Systematic Uncertainties in Searches for Dark Matter No. 2022F2843L” funded by MIUR. E. T. expresses gratitude to the University of Zaragoza for its hospitality during the initial phases of this work. This publication is based on work supported by COST Action COSMIC WISPers CA21106.
\n
\n
\n
The data that support the findings of this article are openly available [114].
\n\nThe supplemental material provides a detailed account of the solar axion flux and its variation with solar radius, a comprehensive modeling of the coronal magnetic field, and an explanation of the anticipated X-ray signal detectable by the NuSTAR satellite. It also includes information on data selection criteria and the specifics of the NuSTAR analysis. Additionally, we examine the systematic uncertainties influencing the newly derived axion limit and evaluate the significance of the NuSTAR results in the context of prior laboratory experiments and astrophysical constraints.
",
"abstract": "We present a novel approach to investigating axions and axionlike particles by studying their potential conversion into x-rays within the Sun's atmospheric magnetic field. Utilizing high-sensitivity data from the nuclear spectroscopic telescope array (NuSTAR) collected during the 2020 solar minimum, along with advanced solar atmospheric magnetic field models, we establish a new limit on the axion-photon coupling strength gaγ \u2272 7.3×10\u207b¹² GeV\u207b¹ at 95% CL for axion masses ma \u2272 4×10\u207b\u2077 eV. This constraint surpasses current ground-based experimental limits, studying previously unexplored regions of the axion-photon coupling parameter space up to masses of ma \u2272 3.4×10\u207b\u2074 eV. These findings mark a significant advancement in our ability to probe axion properties and strengthen indirect searches for dark matter candidates.
",
"date": "2025-10-02",
"date_type": "published",
"publication": "Physical Review Letters",
"volume": "135",
"number": "14",
"publisher": "American Physical Society",
"pagerange": "141001",
"issn": "0031-9007",
"official_url": "https://authors.library.caltech.edu/records/9k91n-qc820",
"funders": {
"items": [
{},
{},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca",
"grant_number": "2022F2843L"
},
{
"grant_number": "CA21106"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1103/18sn-hxtb",
"primary_object": {
"basename": "18sn-hxtb.pdf",
"url": "https://authors.library.caltech.edu/records/9k91n-qc820/files/18sn-hxtb.pdf"
},
"related_objects": [
{
"basename": "supplemental_material_refs_as_in_main.pdf",
"url": "https://authors.library.caltech.edu/records/9k91n-qc820/files/supplemental_material_refs_as_in_main.pdf"
}
],
"pub_year": "2025",
"author_list": "Ruz, J.; Todarello, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jztf3-q8b31",
"eprint_status": "archive",
"datestamp": "2026-04-13 22:50:44",
"lastmod": "2026-04-13 22:50:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Audard",
"given": "Marc"
},
"orcid": "0000-0003-4721-034X"
},
{
"name": {
"family": "Awaki",
"given": "Hisamitsu"
},
"orcid": "0000-0001-7204-4350"
},
{
"name": {
"family": "Ballhausen",
"given": "Ralf"
}
},
{
"name": {
"family": "Bamba",
"given": "Aya"
},
"orcid": "0000-0003-0890-4920"
},
{
"name": {
"family": "Behar",
"given": "Ehud"
}
},
{
"name": {
"family": "Boissay-Malaquin",
"given": "Rozenn"
},
"orcid": "0000-0003-2704-599X"
},
{
"name": {
"family": "Brenneman",
"given": "Laura"
},
"orcid": "0000-0003-2663-1954"
},
{
"name": {
"family": "Brown",
"given": "Gregory V."
}
},
{
"name": {
"family": "Corrales",
"given": "Lia"
},
"orcid": "0000-0002-5466-3817"
},
{
"name": {
"family": "Costantini",
"given": "Elisa"
},
"orcid": "0000-0001-8470-749X"
},
{
"name": {
"family": "Cumbee",
"given": "Renata"
}
},
{
"name": {
"family": "D\u00edaz Trigo",
"given": "Mar\u00eda"
},
"orcid": "0000-0001-7796-4279"
},
{
"name": {
"family": "Done",
"given": "Chris"
},
"orcid": "0000-0002-1065-7239"
},
{
"name": {
"family": "Dotani",
"given": "Tadayasu"
}
},
{
"name": {
"family": "Ebisawa",
"given": "Ken"
}
},
{
"name": {
"family": "Eckart",
"given": "Megan E."
},
"orcid": "0000-0003-3894-5889"
},
{
"name": {
"family": "Eckert",
"given": "Dominique"
},
"orcid": "0000-0001-7917-3892"
},
{
"name": {
"family": "Eguchi",
"given": "Satoshi"
},
"orcid": "0000-0003-2814-9336"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Ezoe",
"given": "Yuichiro"
}
},
{
"name": {
"family": "Foster",
"given": "Adam"
},
"orcid": "0000-0003-3462-8886"
},
{
"name": {
"family": "Fujimoto",
"given": "Ryuichi"
},
"orcid": "0000-0002-2374-7073"
},
{
"name": {
"family": "Fujita",
"given": "Yutaka"
},
"orcid": "0000-0003-0058-9719"
},
{
"name": {
"family": "Fukazawa",
"given": "Yasushi"
}
},
{
"name": {
"family": "Fukushima",
"given": "Kotaro"
},
"orcid": "0000-0001-8055-7113"
},
{
"name": {
"family": "Furuzawa",
"given": "Akihiro"
}
},
{
"name": {
"family": "Gallo",
"given": "Luigi"
},
"orcid": "0009-0006-4968-7108"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garcia",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gu",
"given": "Liyi"
},
"orcid": "0000-0001-9911-7038"
},
{
"name": {
"family": "Guainazzi",
"given": "Matteo"
}
},
{
"name": {
"family": "Hagino",
"given": "Kouichi"
},
"orcid": "0000-0003-4235-5304"
},
{
"name": {
"family": "Hamaguchi",
"given": "Kenji"
}
},
{
"name": {
"family": "Hatsukade",
"given": "Isamu"
}
},
{
"name": {
"family": "Hayashi",
"given": "Katsuhiro"
}
},
{
"name": {
"family": "Hayashi",
"given": "Takayuki"
},
"orcid": "0000-0001-6665-2499"
},
{
"name": {
"family": "Hell",
"given": "Natalie"
},
"orcid": "0000-0003-3057-1536"
},
{
"name": {
"family": "Hodges-Kluck",
"given": "Edmund"
}
},
{
"name": {
"family": "Hornschemeier",
"given": "Ann"
}
},
{
"name": {
"family": "Ichinohe",
"given": "Yuto"
},
"orcid": "0000-0002-6102-1441"
},
{
"name": {
"family": "Ishi",
"given": "Daiki"
}
},
{
"name": {
"family": "Ishida",
"given": "Manabu"
}
},
{
"name": {
"family": "Ishikawa",
"given": "Kumi"
},
"orcid": "0009-0002-2845-5843"
},
{
"name": {
"family": "Ishisaki",
"given": "Yoshitaka"
}
},
{
"name": {
"family": "Kaastra",
"given": "Jelle"
},
"orcid": "0000-0001-5540-2822"
},
{
"name": {
"family": "Kallman",
"given": "Timothy"
}
},
{
"name": {
"family": "Kanemaru",
"given": "Yoshiaki"
},
"orcid": "0000-0002-4541-1044"
},
{
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"name": {
"family": "Katsuda",
"given": "Satoru"
},
"orcid": "0000-0002-1104-7205"
},
{
"name": {
"family": "Kelley",
"given": "Richard"
},
"orcid": "0009-0007-2283-3336"
},
{
"name": {
"family": "Kilbourne",
"given": "Caroline"
}
},
{
"name": {
"family": "Kitamoto",
"given": "Shunji"
}
},
{
"name": {
"family": "Kobayashi",
"given": "Shogo"
},
"orcid": "0000-0001-7773-9266"
},
{
"name": {
"family": "Kohmura",
"given": "Takayoshi"
},
"orcid": "0000-0003-4403-4512"
},
{
"name": {
"family": "Kubota",
"given": "Aya"
},
"orcid": "0000-0002-5413-6304"
},
{
"name": {
"family": "Leutenegger",
"given": "Maurice"
},
"orcid": "0000-0002-3331-7595"
},
{
"name": {
"family": "Loewenstein",
"given": "Michael"
}
},
{
"name": {
"family": "Maeda",
"given": "Yoshitomo"
}
},
{
"name": {
"family": "Markevitch",
"given": "Maxim"
},
"orcid": "0000-0003-0144-4052"
},
{
"name": {
"family": "Matsumoto",
"given": "Hironori"
}
},
{
"name": {
"family": "Matsushita",
"given": "Kyoko"
}
},
{
"name": {
"family": "McCammon",
"given": "Dan"
},
"orcid": "0000-0001-5170-4567"
},
{
"name": {
"family": "McNamara",
"given": "Brian"
}
},
{
"name": {
"family": "Mernier",
"given": "Fran\u00e7ois"
},
"orcid": "0000-0002-7031-4772"
},
{
"name": {
"family": "Miller",
"given": "Eric D."
},
"orcid": "0000-0002-3031-2326"
},
{
"name": {
"family": "Miller",
"given": "Jon M."
},
"orcid": "0000-0003-2869-7682"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Mizumoto",
"given": "Misaki"
},
"orcid": "0000-0003-2161-0361"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
}
},
{
"name": {
"family": "Mori",
"given": "Koji"
},
"orcid": "0000-0002-0018-0369"
},
{
"name": {
"family": "Mukai",
"given": "Koji"
},
"orcid": "0000-0002-8286-8094"
},
{
"name": {
"family": "Murakami",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Nakajima",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Nakazawa",
"given": "Kazuhiro"
}
},
{
"name": {
"family": "Ness",
"given": "Jan-Uwe"
},
"orcid": "0000-0003-0440-7193"
},
{
"name": {
"family": "Nobukawa",
"given": "Kumiko"
},
"orcid": "0000-0002-0726-7862"
},
{
"name": {
"family": "Nobukawa",
"given": "Masayoshi"
}
},
{
"name": {
"family": "Noda",
"given": "Hirofumi"
},
"orcid": "0000-0001-6020-517X"
},
{
"name": {
"family": "Odaka",
"given": "Hirokazu"
}
},
{
"name": {
"family": "Ogawa",
"given": "Shoji"
},
"orcid": "0000-0002-5701-0811"
},
{
"name": {
"family": "Ogorzalek",
"given": "Anna"
},
"orcid": "0000-0003-4504-2557"
},
{
"name": {
"family": "Okajima",
"given": "Takashi"
},
"orcid": "0000-0002-6054-3432"
},
{
"name": {
"family": "Ota",
"given": "Naomi"
},
"orcid": "0000-0002-2784-3652"
},
{
"name": {
"family": "Paltani",
"given": "Stephane"
},
"orcid": "0000-0002-8108-9179"
},
{
"name": {
"family": "Petre",
"given": "Robert"
},
"orcid": "0000-0003-3850-2041"
},
{
"name": {
"family": "Plucinsky",
"given": "Paul"
},
"orcid": "0000-0003-1415-5823"
},
{
"name": {
"family": "Porter",
"given": "Frederick S."
},
"orcid": "0000-0002-6374-1119"
},
{
"name": {
"family": "Pottschmidt",
"given": "Katja"
}
},
{
"name": {
"family": "Sato",
"given": "Kosuke"
},
"orcid": "0000-0001-5774-1633"
},
{
"name": {
"family": "Sato",
"given": "Toshiki"
}
},
{
"name": {
"family": "Sawada",
"given": "Makoto"
},
"orcid": "0000-0003-2008-6887"
},
{
"name": {
"family": "Seta",
"given": "Hiromi"
}
},
{
"name": {
"family": "Shidatsu",
"given": "Megumi"
},
"orcid": "0000-0001-8195-6546"
},
{
"name": {
"family": "Simionescu",
"given": "Aurora"
}
},
{
"name": {
"family": "Smith",
"given": "Randall"
},
"orcid": "0000-0003-4284-4167"
},
{
"name": {
"family": "Suzuki",
"given": "Hiromasa"
}
},
{
"name": {
"family": "Szymkowiak",
"given": "Andrew"
},
"orcid": "0000-0002-4974-687X"
},
{
"name": {
"family": "Takahashi",
"given": "Hiromitsu"
},
"orcid": "0000-0001-6314-5897"
},
{
"name": {
"family": "Takeo",
"given": "Mai"
}
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tamura",
"given": "Keisuke"
},
"orcid": "0009-0004-7101-4503"
},
{
"name": {
"family": "Tanaka",
"given": "Takaaki"
},
"orcid": "0000-0002-4383-0368"
},
{
"name": {
"family": "Tanimoto",
"given": "Atsushi"
},
"orcid": "0000-0002-0114-5581"
},
{
"name": {
"family": "Tashiro",
"given": "Makoto"
},
"orcid": "0000-0002-5097-1257"
},
{
"name": {
"family": "Terada",
"given": "Yukikatsu"
}
},
{
"name": {
"family": "Terashima",
"given": "Yuichi"
},
"orcid": "0000-0003-1780-5481"
},
{
"name": {
"family": "Tsuboi",
"given": "Yohko"
},
"orcid": "0000-0001-9943-0024"
},
{
"name": {
"family": "Tsujimoto",
"given": "Masahiro"
},
"orcid": "0000-0002-9184-5556"
},
{
"name": {
"family": "Tsunemi",
"given": "Hiroshi"
},
"orcid": "0000-0003-4379-5643"
},
{
"name": {
"family": "Tsuru",
"given": "Takeshi"
},
"orcid": "0000-0002-5504-4903"
},
{
"name": {
"family": "T\u00fcmer",
"given": "Ay\u015feg\u00fcl"
},
"orcid": "0000-0002-3132-8776"
},
{
"name": {
"family": "Uchida",
"given": "Hiroyuki"
}
},
{
"name": {
"family": "Uchida",
"given": "Nagomi"
}
},
{
"name": {
"family": "Uchida",
"given": "Yuusuke"
}
},
{
"name": {
"family": "Uchiyama",
"given": "Hideki"
},
"orcid": "0000-0003-4580-4021"
},
{
"name": {
"family": "Ueda",
"given": "Yoshihiro"
},
"orcid": "0000-0001-7821-6715"
},
{
"name": {
"family": "Uno",
"given": "Shinichiro"
}
},
{
"name": {
"family": "Vink",
"given": "Jacco"
}
},
{
"name": {
"family": "Watanabe",
"given": "Shin"
}
},
{
"name": {
"family": "Williams",
"given": "Brian J."
},
"orcid": "0000-0003-2063-381X"
},
{
"name": {
"family": "Yamada",
"given": "Satoshi"
},
"orcid": "0000-0002-9754-3081"
},
{
"name": {
"family": "Yamada",
"given": "Shinya"
},
"orcid": "0000-0003-4808-893X"
},
{
"name": {
"family": "Yamaguchi",
"given": "Hiroya"
}
},
{
"name": {
"family": "Yamaoka",
"given": "Kazutaka"
}
},
{
"name": {
"family": "Yamasaki",
"given": "Noriko"
},
"orcid": "0000-0003-4885-5537"
},
{
"name": {
"family": "Yamauchi",
"given": "Makoto"
},
"orcid": "0000-0003-1100-1423"
},
{
"name": {
"family": "Yamauchi",
"given": "Shigeo"
}
},
{
"name": {
"family": "Yaqoob",
"given": "Tahir"
}
},
{
"name": {
"family": "Yoneyama",
"given": "Tomokage"
},
"orcid": "0000-0002-2683-6856"
},
{
"name": {
"family": "Yoshida",
"given": "Tessei"
}
},
{
"name": {
"family": "Yukita",
"given": "Mihoko"
},
"orcid": "0000-0001-6366-3459"
},
{
"name": {
"family": "Zhuravleva",
"given": "Irina"
},
"orcid": "0000-0001-7630-8085"
},
{
"name": {
"family": "Diez",
"given": "Camille"
},
"orcid": "0000-0001-6520-4600"
},
{
"name": {
"family": "Fukumura",
"given": "Keigo"
},
"orcid": "0000-0001-5709-7606"
},
{
"name": {
"family": "Li",
"given": "Chen"
},
"orcid": "0000-0001-5493-7585"
},
{
"name": {
"family": "Mehdipour",
"given": "Missagh"
},
"orcid": "0000-0002-4992-4664"
},
{
"name": {
"family": "Panagiotou",
"given": "Christos"
},
"orcid": "0009-0001-9034-6261"
},
{
"name": {
"family": "Signorini",
"given": "Matilde"
},
"orcid": "0000-0002-8177-6905"
},
{
"name": {
"family": "Zhao",
"given": "Keqin"
},
"orcid": "0000-0003-1252-8227"
}
]
},
"title": "Delving into the depths of NGC 3783 with XRISM. II. Cross-calibration of X-ray instruments used in the large, multi-mission observational campaign",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "instrumentation: spectrographs; methods: data analysis; space vehicles: instruments; techniques: spectroscopic; galaxies: active",
"note": "© The Authors 2025. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nWe are grateful to the mission planners of all missions involved for their efforts in scheduling and re-scheduling all our coordinated observations as well as possible, which is not a trivial task. We thank Lucien Kuiper (SRON) for providing us with the velocity corrections to the Solar System Barycentre. SRON is supported financially by NWO, the Netherlands organization for scientific research. Part of this work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The material is based upon work supported by NASA under award number 80GSFC21M0002. This work was supported by JSPS KAKENHI grant numbers JP22H00158, JP22H01268, JP22K03624, JP23H04899, JP21K13963, JP24K00638, JP24K17105, JP21K13958, JP21H01095, JP23K20850, JP24H00253, JP21K03615, JP24K00677, JP20K14491, JP23H00151, JP19K21884, JP20H01947, JP20KK0071, JP23K20239, JP24K00672, JP24K17104, JP24K17093, JP20K04009, JP21H04493, JP20H01946, JP23K13154, JP19K14762, JP20H05857, and JP23K03459. This work was supported by NASA grant numbers 80NSSC20K0733, 80NSSC18K0978, 80NSSC20K0883, 80NSSC20K0737, 80NSSC24K0678, 80NSSC18K1684, and 80NNSC22K1922. LC acknowledges support from NSF award 2205918. CD acknowledges support from STFC through grant ST/T000244/1. L. Gallo acknowledges financial support from Canadian Space Agency grant 18XARMSTMA. MS acknowledges the support by the RIKEN Pioneering Project Evolution of Matter in the Universe (r-EMU) and Rikkyo University Special Fund for Research (Rikkyo SFR). AT and the present research are in part supported by the Kagoshima University postdoctoral research program (KU-DREAM). SY acknowledges support by the RIKEN SPDR Program. IZ acknowledges partial support from the Alfred P. Sloan Foundation through the Sloan Research Fellowship. This work was supported by the JSPS Core-to-Core Program, JPJSCCA20220002. The material is based on work supported by the Strategic Research Center of Saitama University. M. Mehdipour acknowledges support from NASA through the XRISM Guest Scientist (XGS) grant 80NSSC23K0995, a grant for HST program number 17273 from the Space Telescope Science Institute (operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555), and NuSTAR grant 80NSSC25K7126. We deeply regret that our co-author Katja Pottschmidt passed away on 17 June 2025, the same day that this paper was submitted.
",
"abstract": "Context. Accurate X-ray spectroscopic measurements are fundamental for deriving basic physical parameters of the most abundant baryon components in the Universe. The plethora of X-ray observatories currently operational enables a panchromatic view of the high-energy emission of celestial sources. However, uncertainties in the energy-dependent calibration of the instrument transfer functions (e.g. the effective area, energy redistribution, or gain) can limit - and historically, did limit - the accuracy of X-ray spectroscopic measurements. Aims. We revised the status of the cross-calibration among the scientific payload on board four operation missions: Chandra, NuSTAR, XMM-Newton, and the recently launched XRISM. XRISM carries the micro-calorimeter Resolve, which yields the best energy resolution at energies ≥2 keV. For this purpose, we used the data from a 10-day-long observational campaign targeting the nearby active galactic nucleus NGC 3783, carried out in July 2024. Methods. We present a novel model-independent method for assessing the cross-calibration status that is based on a multi-node spline of the spectra with the highest-resolving power (XRISM/Resolve in our campaign). We also estimated the impact of the intrinsic variability of NGC 3783 on the cross-calibration status due to the different time coverages of participating observatories and performed an empirical reassessment of the Resolve throughput at low energies. Results. Based on this analysis, we derived a set of energy-dependent correction factors of the observed responses, enabling a statistically robust analysis of the whole spectral dataset. They will be employed in subsequent papers describing the astrophysical results of the campaign.
",
"date": "2025-10",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "702",
"publisher": "EDP Sciences",
"pagerange": "A147",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/jztf3-q8b31",
"funders": {
"items": [
{
"grant_number": "DE-AC52-07NA27344"
},
{
"agency": "NASA",
"grant_number": "80GSFC21M0002"
},
{
"agency": "JSPS",
"grant_number": "JP22H00158"
},
{
"agency": "JSPS",
"grant_number": "JP22H01268"
},
{
"agency": "JSPS",
"grant_number": "JP22K03624"
},
{
"agency": "JSPS",
"grant_number": "JP23H04899"
},
{
"agency": "JSPS",
"grant_number": "JP21K13963"
},
{
"agency": "JSPS",
"grant_number": "JP24K00638"
},
{
"agency": "JSPS",
"grant_number": "JP24K17105"
},
{
"agency": "JSPS",
"grant_number": "JP21K13958"
},
{
"agency": "JSPS",
"grant_number": "JP21H01095"
},
{
"agency": "JSPS",
"grant_number": "JP23K20850"
},
{
"agency": "JSPS",
"grant_number": "P24H00253"
},
{
"agency": "JSPS",
"grant_number": "JP21K03615"
},
{
"agency": "JSPS",
"grant_number": "JP24K00677"
},
{
"agency": "JSPS",
"grant_number": "JP20K14491"
},
{
"agency": "JSPS",
"grant_number": "JP23H00151"
},
{
"agency": "JSPS",
"grant_number": "JP19K21884"
},
{
"agency": "JSPS",
"grant_number": "JP20H01947"
},
{
"agency": "JSPS",
"grant_number": "JP20KK0071"
},
{
"agency": "JSPS",
"grant_number": "JP23K20239"
},
{
"agency": "JSPS",
"grant_number": "JP24K00672"
},
{
"agency": "JSPS",
"grant_number": "JP24K17104"
},
{
"agency": "JSPS",
"grant_number": "JP24K17093"
},
{
"agency": "JSPS",
"grant_number": "JP20K04009"
},
{
"agency": "JSPS",
"grant_number": "JP21H04493"
},
{
"agency": "JSPS",
"grant_number": "JP20H01946"
},
{
"agency": "JSPS",
"grant_number": "JP23K13154"
},
{
"agency": "JSPS",
"grant_number": "JP19K14762"
},
{
"agency": "JSPS",
"grant_number": "JP20H05857"
},
{
"agency": "JSPS",
"grant_number": "JP23K03459"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0733"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0978"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0883"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0737"
},
{
"agency": "NASA",
"grant_number": "80NSSC24K0678"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1684"
},
{
"agency": "NASA",
"grant_number": "80NNSC22K1922"
},
{
"agency": "NSF",
"grant_number": "2205918"
},
{
"agency": "STFC",
"grant_number": "ST/T000244/1"
},
{
"grant_number": "18XARMSTMA"
},
{},
{},
{},
{},
{
"agency": "JSPS core",
"grant_number": "JPJSCCA20220002"
},
{
"agency": "NASA",
"grant_number": "80NSSC23K0995"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555/17273"
},
{
"agency": "NASA",
"grant_number": "80NSSC25K7126"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"corp_creators": {
"items": [
"XRISM Collaboration"
]
},
"doi": "10.1051/0004-6361/202556000",
"primary_object": {
"basename": "aa56000-25.pdf",
"url": "https://authors.library.caltech.edu/records/jztf3-q8b31/files/aa56000-25.pdf"
},
"pub_year": "2025",
"author_list": "Audard, Marc; Awaki, Hisamitsu; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4wnm7-z7w69",
"eprint_status": "archive",
"datestamp": "2025-09-02 15:33:35",
"lastmod": "2026-03-10 03:30:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Lopez",
"given": "Fiona"
}
},
{
"name": {
"family": "Wik",
"given": "Daniel R."
},
"orcid": "0000-0001-9110-2245"
},
{
"name": {
"family": "Potter",
"given": "Cicely"
},
"orcid": "0009-0003-7738-9173"
},
{
"name": {
"family": "Rojas Bolivar",
"given": "Randall A."
},
"orcid": "0000-0002-8882-6426"
},
{
"name": {
"family": "T\u00fcmer",
"given": "Ay\u015feg\u00fcl"
},
"orcid": "0000-0002-3132-8776"
},
{
"name": {
"family": "Eckert",
"given": "Dominique"
},
"orcid": "0000-0001-7917-3892"
},
{
"name": {
"family": "Gastaldello",
"given": "Fabio"
},
"orcid": "0000-0002-9112-0184"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
},
{
"name": {
"family": "Maughan",
"given": "Ben"
},
"orcid": "0000-0003-0791-9098"
},
{
"name": {
"family": "Miller",
"given": "Eric D."
},
"orcid": "0000-0002-3031-2326"
},
{
"name": {
"family": "Schellenberger",
"given": "Gerrit"
},
"orcid": "0000-0002-4962-0740"
},
{
"name": {
"family": "Wallbank",
"given": "A. N."
}
}
]
},
"title": "Cross Calibration of Galaxy Cluster Temperatures Measured with NuSTAR, XMM-Newton, and Chandra",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galaxy clusters; Galactic and extragalactic astronomy; Cosmology; Telescopes; Calibration; X-ray astronomy",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\n\n
\n
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n
\n
\n
\n
F.L., D.R.W., and C.P. acknowledge support from the NuSTAR NASA JPL subcontract RSA1688622, NASA grant 80NSSC20K1000, and the NSF-supported REU program at the University of Utah. B.J.M. acknowledges support from Science and Technology Facilities Council grants ST/V000454/1 and ST/Y002008/1. This work made use of data from the NuSTAR mission, which is led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. In addition, it employs a list of Chandra data sets, obtained by the Chandra X-ray Observatory, contained in the Chandra Data Collection DOI: 10.25574/cdc.418.
\n
\n
\n
The use of galaxy clusters to constrain cosmology is limited in part due to uncertainties in derived cluster masses, which often depend on the gas temperature. Unfortunately, there exists a longstanding discrepancy in temperature measurements of the same galaxy clusters made by the two most sensitive X-ray observatories, Chandra and XMM-Newton. The NuSTAR X-ray Observatory’s greater sensitivity to the exponential turnover in the bremsstrahlung continuum allows for more precise and potentially more accurate galaxy cluster temperature estimates, especially given its unique ability to independently calibrate its optics in orbit. We present new NuSTAR spectra of 10 relaxed (5 keV < kT < 10 keV) clusters, extracted from identical regions as previous spectra from Chandra and XMM-Newton. The 3–20 keV spectra are well fit by single temperature models, and fits done in narrower bandpasses provide no clear evidence in support of the existence of multi-temperature gas. We find NuSTAR temperatures are typically ∼15% higher than XMM-Newton temperatures. In contrast, good agreement is found between NuSTAR and Chandra temperatures for clusters with kT \u2272 7 keV, with Chandra measurements exceeding NuSTAR’s in hotter systems. When more clusters are included, the trend is reinforced and can be extended to higher temperatures. A generic increase to Chandra’s E > 2 keV effective area (∼5% at 5 keV) is found to explain the trend reasonably well. These results demonstrate the potential for NuSTAR data to address the two-decade-old temperature discrepancy between Chandra and XMM-Newton.
\n
© The Author(s) 2025. Published by Oxford University Press on behalf of the Astronomical Society of Japan.
\n\n
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
\n
We gratefully acknowledge the hard work over many years of all of the engineers and scientists who made the XRISM mission possible. Part of this work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The material is based upon work supported by NASA under award numbers 80GSFC21M0002 and 80GSFC24M0006. This work was supported by JSPS KAKENHI grant numbers JP23H00121, JP22H00158, JP22H01268, JP22K03624, JP23H04899, JP21K13963, JP24K00638, JP24K17105, JP21K13958, JP21H01095, JP23K20850, JP24H00253, JP21K03615, JP24K00677, JP20K14491, JP23H00151, JP19K21884, JP20H01947, JP20KK0071, JP23K20239, JP24K00672, JP24K17104, JP24K17093, JP20K04009, JP21H04493, JP20H01946, JP23K13154, JP19K14762, JP20H05857, and JP23K03459. This work was supported by NASA grant numbers 80NSSC20K0733, 80NSSC18K0978, 80NSSC20K0883, 80NSSC20K0737, 80NSSC24K0678, 80NSSC18K1684, 80NSSC23K0650, and 80NNSC22K1922. LC acknowledges support from NSF award 2205918. CD acknowledges support from STFC through grant ST/T000244/1. LG acknowledges financial support from Canadian Space Agency grant 18XARMSTMA. NO acknowledges partial support by the Organization for the Promotion of Gender Equality at Nara Women’s University. MS acknowledges the support by the RIKEN Pioneering Project Evolution of Matter in the Universe (r-EMU) and Rikkyo University Special Fund for Research (Rikkyo SFR). AT and the present research are in part supported by the Kagoshima University postdoctoral research program (KU-DREAM). SY acknowledges support by the RIKEN SPDR Program. TY acknowledges support by NASA under award number 80GSFC24M0006. IZ acknowledges partial support from the Alfred P. Sloan Foundation through the Sloan Research Fellowship. SE acknowledges the financial contribution from the contracts Prin-MUR 2022 supported by Next Generation EU (M4.C2.1.1, n.20227RNLY3 The concordance cosmological model: stress-tests with galaxy clusters), from the European Union’s Horizon 2020 Programme under the AHEAD2020 project (grant agreement n. 871158), and from the INAF Theory grant 1.05.24.05.10. LL acknowledges the financial contribution from the INAF grant 1.05.12.04.01. This work was supported by the JSPS Core-to-Core Program, JPJSCCA20220002. The material is based on work supported by the Strategic Research Center of Saitama University.
",
"abstract": "We report on a detailed spectroscopic study of the gas dynamics and hydrostatic mass bias of the galaxy cluster Abell 2029, utilizing high-resolution observations from XRISM Resolve. Abell 2029, known for its cool core and relaxed X-ray morphology, provides an excellent opportunity to investigate the influence of gas motions beyond the central region. Expanding upon prior studies that revealed low turbulence and bulk motions within the core, our analysis covers regions out to the scale radius R\u2082\u2085\u2080\u2080 (670 kpc) based on three radial pointings extending from the cluster center toward the northern side. We obtain accurate measurements of bulk and turbulent velocities along the line of sight. The results indicate that non-thermal pressure accounts for no more than 2% of the total pressure at all radii, with a gradual decrease outward. The observed radial trend differs from many numerical simulations, which often predict an increase in non-thermal pressure fraction at larger radii. These findings suggest that deviations from hydrostatic equilibrium are small, leading to a hydrostatic mass bias of around 2% across the observed area.
",
"date": "2025-09",
"date_type": "published",
"publication": "Publications of the Astronomical Society of Japan",
"volume": "77",
"number": "S1",
"publisher": "Oxford University Press (OUP)",
"pagerange": "S242-S253",
"issn": "0004-6264",
"official_url": "https://authors.library.caltech.edu/records/30wzr-nng02",
"funders": {
"items": [
{
"grant_number": "DE-AC52-07NA27344"
},
{
"grant_number": "80GSFC21M0002"
},
{
"grant_number": "80GSFC24M0006"
},
{
"grant_number": "JP23H00121"
},
{
"grant_number": "JP22H00158"
},
{
"grant_number": "JP22H01268"
},
{
"grant_number": "JP22K03624"
},
{
"grant_number": "JP23H04899"
},
{
"grant_number": "JP21K13963"
},
{
"grant_number": "JP24K00638"
},
{
"grant_number": "JP24K17105"
},
{
"grant_number": "JP21K13958"
},
{
"grant_number": "JP21H01095"
},
{
"grant_number": "JP23K20850"
},
{
"grant_number": "JP24H00253"
},
{
"grant_number": "JP21K03615"
},
{
"grant_number": "JP24K00677"
},
{
"grant_number": "JP20K14491"
},
{
"grant_number": "JP23H00151"
},
{
"grant_number": "JP19K21884"
},
{
"grant_number": "JP20H01947"
},
{
"grant_number": "JP20KK0071"
},
{
"grant_number": "JP23K20239"
},
{
"grant_number": "JP24K00672"
},
{
"grant_number": "JP24K17104"
},
{
"grant_number": "JP24K17093"
},
{
"grant_number": "JP20K04009"
},
{
"grant_number": "JP21H04493"
},
{
"grant_number": "JP20H01946"
},
{
"grant_number": "JP23K13154"
},
{
"grant_number": "JP19K14762"
},
{
"grant_number": "JP20H05857"
},
{
"grant_number": "JP23K03459"
},
{
"grant_number": "80NSSC20K0733"
},
{
"grant_number": "80NSSC18K0978"
},
{
"grant_number": "80NSSC20K0883"
},
{
"grant_number": "80NSSC20K0737"
},
{
"grant_number": "80NSSC24K0678"
},
{
"grant_number": "80NSSC18K1684"
},
{
"grant_number": "80NSSC23K0650"
},
{
"grant_number": "80NNSC22K1922"
},
{
"grant_number": "2205918"
},
{
"grant_number": "ST/T000244/1"
},
{
"grant_number": "18XARMSTMA"
},
{},
{},
{},
{},
{
"grant_number": "80GSFC24M0006"
},
{},
{
"grant_number": "20227RNLY3"
},
{
"grant_number": "871158"
},
{
"grant_number": "1.05.24.05.10"
},
{
"grant_number": "1.05.12.04.01"
},
{
"grant_number": "JPJSCCA20220002"
},
{}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"corp_creators": {
"items": [
"XRISM Collaboration"
]
},
"doi": "10.1093/pasj/psaf055",
"primary_object": {
"basename": "psaf055.pdf",
"url": "https://authors.library.caltech.edu/records/30wzr-nng02/files/psaf055.pdf"
},
"pub_year": "2025",
"author_list": "Audard, Marc; Awaki, Hisamitsu; et al."
},
{
"id": "https://authors.library.caltech.edu/records/abb5d-k2h91",
"eprint_status": "archive",
"datestamp": "2025-08-25 20:41:17",
"lastmod": "2026-03-10 00:34:17",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "El Byad",
"given": "Hamza"
},
"orcid": "0009-0001-5473-4953"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Columbu",
"given": "Silvia"
},
"orcid": "0000-0001-5420-0719"
},
{
"name": {
"family": "Rodriguez",
"given": "Giuseppe"
},
"orcid": "0000-0001-9054-8712"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Middleton",
"given": "Matthew J."
},
"orcid": "0000-0002-8183-2970"
},
{
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah"
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"name": {
"family": "F\u00fcrst",
"given": "Felix"
}
},
{
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"name": {
"family": "Imbrogno",
"given": "Matteo"
},
"orcid": "0000-0001-8688-9784"
},
{
"name": {
"family": "Lai",
"given": "Eleonora Veronica"
},
"orcid": "0000-0002-6421-2198"
},
{
"name": {
"family": "Maccarone",
"given": "Thomas"
},
"orcid": "0000-0003-0976-4755"
}
]
},
"title": "A NuSTAR Study of Quasiperiodic Oscillations from the Ultraluminous X-Ray Sources in M82",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Ultraluminous x-ray sources; X-ray binary stars; X-ray astronomy; Compact objects; Accretion; Time domain astronomy",
"note": "© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors wish to thank Phil Uttley for discussions on the spectral cleaning procedure. M.B. was supported in part by the Italian Research Center on High Performance Computing Big Data and Quantum Computing (ICSC), project funded by European Union—NextGenerationEU—and National Recovery and Resilience Plan (NRRP)—Mission 4 Component 2 within the activities of Spoke 3 (Astrophysics and Cosmos Observations). D.J.W. acknowledges support from the Science and Technology Facilities Council (STFC; grant code ST/Y001060/1).
\n\nastropy (Astropy Collaboration et al. 2013, 2018, 2022), Stingray (D. Huppenkothen et al. 2019), CIAO (A. Fruscione et al. 2006), Astroquery (A. Ginsburg et al. 2019).
",
"abstract": "\n
The study of quasiperiodic oscillations (QPOs) in X-ray binaries provides valuable insights into the physics of accretion around compact objects. The M82 galaxy hosts multiple ultraluminous X-ray sources, including two prominent ones—X-1 and X-2—where X-1 is suspected to harbor an intermediate-mass black hole. In this work, we analyze data from 39 NuSTAR observations acquired between 2014 and 2024 to investigate the aperiodic X-ray variability in M82. In particular, we study in detail the evolution of the QPOs from M82 X-1 in the range 20–300 mHz. We do not find additional timing features in the data, besides a frequently present broad noise component at lower frequencies. The QPO behaves similarly to other classes of low-frequency oscillations in accreting compact objects, both black holes and neutron stars.
\n
© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nB.G. would like the thank the anonymous referee for productive comments and Dr. Ed Nathan and Dr. Malu Sudha for useful discussions on the timing analysis sections. This work was supported by the National Aeronautics and Space Administration (NASA) under grant No. 80NSSC22K1812 issued through the NuSTAR Guest Observer program. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
",
"abstract": "\n
We report on the first focused NuSTAR observations of the neutron star low mass X-ray binary GS 1826-238, the “Clocked Burster,” since the extended soft state began in 2014. Throughout this day-long observation, we see spectral variability that is consistent with the “banana” branch of atoll LMXBs. The NuSTAR hard X-ray spectrum is consistent with that seen during the initial soft-state excursion in 2014 and is modeled as a double Comptonized plasma: one with low temperature and high optical depth, the other with high temperature and low optical depth. The spectral variations that we see in this source are mostly consistent with variations in the optical depth of the hot component, though the total flux from the source remains nearly constant. A single Type I X-ray burst is seen during this observation, which has a short main peak (timescales of seconds) followed by an extended tail of emission. The shape of this burst is not consistent with a PRE and provide diagnostic information on the regions of the NS surface supplying the fuel for the thermonuclear reaction.
\n
© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nAnalysis software (L. B. Wilson 2022) used herein can be found on GitHub.29 and referenced in V. Angelopoulos et al. (2019). All ACE, Wind, and STEREO data discussed herein are available through SPDF/CDAWeb.30 PSP was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living With a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the PSP mission. The FIELDS experiment was developed and is operated under NASA contract NNN06AA01C. J.S.H., S.D.B., D.M.M., C.M.S.C., R.L., M.L.S., and A.S. are supported through PSP contracts. All PSP data were provided by the instrument teams and are soon to be released for public archival at SPDF/CDAWeb. J.G.M. acknowledges the support of the NASA PSP grant NNN06AA01C. I.C.J. is grateful for support by the Research Council of Finland (SHOCKSEE, grant No. 346902), and the European Union’s (EU’s) Horizon 2020 research and innovation program under grant agreement No. 101134999 (SOLER). The study reflects only the authors’ view and the European Commission is not responsible for any use that may be made of the information it contains. I.C.J. was also supported by the International Space Science Institute (ISSI) in Bern through ISSI International Team project No. 23-575, “Collisionless Shock as a Self-Regulatory System” and through the Visiting Scientist program. A.K. acknowledges financial support from NASA NNN06AA01C (PSP EPI-Lo) contract and NASA’s HGIO grant 80NSSC24K0555. G.D.B. acknowledges the support of the IS\u2299IS instrument suite on NASA’s PSP Mission, contract NNN06AA01C. D.M.M. acknowledges the support of the NASA PSP grant NNN06AA01C.
",
"abstract": "We report observations of an interplanetary (IP) shock observed by Parker Solar Probe (PSP) on 2024 September 29 at ∼07:50:29 UTC. PSP was only ∼17.07 Rs from the Sun, making this one of the closest observed IP shocks to date. The IP shock was a weak (Mf ∼ 1.2), quasi-perpendicular (θBn ∼ 50°), and of moderate speed (Vshn ∼ 465 km s−1). The standard shock acceleration mechanisms (e.g., Fermi acceleration) predict that such an unremarkable shock cannot generate energetic particles (i.e., over 4 orders of magnitude above thermal energies), which is supported by decades of IP shock observations near 1 au. However, ∼MeV energy protons with an inverse velocity arrival and synchrotron radiation (due to ∼MeV energy electrons) were observed upstream. This raised the question of what was different about this shock. One observation was that of a fast/magnetosonic-whistler precursor with peak-to-peak magnetic field amplitudes >700 nT, electric fields >2000 mV m−1, and Poynting fluxes >230 mW m−2. These are 2 orders of magnitude larger than any previously observed whistler precursor. To put the amplitudes in context, the lower bound Poynting flux estimates are >200 times what is necessary to drive the terrestrial aurora. Note that the normalized wave parameters (e.g., frequency) were found to be consistent with previous studies near 1 au. Thus, the precursors cannot likely generate a larger fraction of energetic particles than similar precursors near 1 au. However, the much larger amplitudes would allow for higher maximum energies. This raises important questions about inaccessible shocks in more extreme astrophysical environments and what potential energization they may have in light of these observations.
",
"date": "2025-07-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "987",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "31",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/s56ce-vtw64",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
},
{
"grant_number": "346902"
},
{
"grant_number": "101134999"
},
{
"grant_number": "80NSSC24K0555"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/add6a8",
"primary_object": {
"basename": "Wilson_2025_ApJ_987_31.pdf",
"url": "https://authors.library.caltech.edu/records/s56ce-vtw64/files/Wilson_2025_ApJ_987_31.pdf"
},
"pub_year": "2025",
"author_list": "Wilson, Lynn B.; Mitchell, J. Grant; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5p7gt-89g42",
"eprint_status": "archive",
"datestamp": "2025-11-13 16:05:11",
"lastmod": "2026-03-10 00:34:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Singer",
"given": "Leo P."
},
"orcid": "0000-0001-9898-5597"
},
{
"name": {
"family": "Criswell",
"given": "Alexander W."
},
"orcid": "0000-0002-9225-7756"
},
{
"name": {
"family": "Leggio",
"given": "Sydney C."
},
"orcid": "0009-0000-9360-4759"
},
{
"name": {
"family": "Kiendrebeogo",
"given": "R. Weizmann"
},
"orcid": "0000-0002-9108-5059"
},
{
"name": {
"family": "Coughlin",
"given": "Michael W."
},
"orcid": "0000-0002-8262-2924"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"name": {
"family": "Gezari",
"given": "Suvi"
},
"orcid": "0000-0003-3703-5154"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0003-2992-8024"
},
{
"id": "Kasliwal-M-M",
"name": {
"family": "Kasliwal",
"given": "Mansi M."
},
"orcid": "0000-0002-5619-4938"
},
{
"name": {
"family": "Morris",
"given": "Brett M."
},
"orcid": "0000-0003-2528-3409"
},
{
"name": {
"family": "Tollerud",
"given": "Erik"
},
"orcid": "0000-0002-9599-310X"
},
{
"name": {
"family": "Cenko",
"given": "S. Bradley"
},
"orcid": "0000-0003-1673-970X"
}
]
},
"title": "Optimal Follow-up of Gravitational-wave Events with the UltraViolet EXplorer (UVEX)",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Computational methods; Gravitational wave astronomy; Open source software; Ultraviolet observatories; Ultraviolet transient sources; Wide-field telescopes",
"note": "© 2025. The Author(s). Published by IOP Publishing Ltd on behalf of the Astronomical Society of the Pacific (ASP). Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThis work was performed in part at the Aspen Center for Physics, which is supported by the U.S. National Science Foundation (NSF) grant PHY-2210452.
\nThis work used Expanse at the San Diego Supercomputing Center (SDSC) and Delta at the National Center for Supercomputing Applications (NCSA) through allocation AST200029, “Towards a complete catalog of variable sources to support efficient searches for compact binary mergers and their products,” from the Advanced Cyberinfrastructure Coordination Ecosystem: Services and Support (ACCESS) program, which is supported by NSF grants #2138259, #2138286, #2138307, #2137603, and #2138296.
\nS.C.L. and M.W.C. acknowledge support from NSF with grant Nos. PHY-2308862 and PHY-2117997.
\nWe thank Steve Crawford at NASA Headquarters for help and support with the NASA software release process.
\nThe code, data, and software environment to reproduce the figures and tables in this paper are available from Zenodo (Singer 2025).
\nThis is LIGO document P2500008-v3.
\n\nastropy (Astropy Collaboration et al. 2013, 2018), astroquery (Ginsburg et al. 2019), dust_extinction (Gordon 2024), dustmaps (Green 2018), healpix (Górski et al. 2005), healpy (Zonca et al. 2019), ligo.skymap (Singer & Price 2016; Singer et al. 2016a, 2016b), matplotlib (Hunter 2007), m4opt (Singer et al. 2025), numpy (Harris et al. 2020), regions (Bradley et al. 2022), scipy (Virtanen et al. 2020), spiceypy (Annex et al. 2020), sympy (Meurer et al. 2017), synphot (STScI Development Team 2018).
",
"abstract": "The UltraViolet EXplorer (UVEX) is a wide-field ultraviolet space telescope selected as a NASA Medium-Class Explorer mission for launch in 2030. UVEX will undertake deep, cadenced surveys of the entire sky to probe low mass galaxies and explore the ultraviolet (UV) time-domain sky, and it will carry the first rapidly deployable UV spectroscopic capability for a broad range of science applications. One of UVEX’s prime objectives is to follow up gravitational wave (GW) binary neutron star mergers as targets of opportunity (ToOs), rapidly scanning across their localization regions to search for their kilonova (KN) counterparts. Early-time multiband ultraviolet light curves of KNe are key to explaining the interplay between jet and ejecta in binary neutron star mergers. Owing to high Galactic extinction in the ultraviolet and the variation of GW distance estimates over the sky, the sensitivity to kilonovae can vary significantly across the GW localization and even across the footprint of a single image given UVEX’s large field of view. Good ToO observing strategies to trade off between area and depth are neither simple nor obvious. We present an optimal strategy for GW follow-up with UVEX in which exposure time is adjusted dynamically for each field individually to maximize the overall probability of detection. We model the scheduling problem using the expressive and powerful mathematical framework of mixed integer linear programming (MILP), and employ a state-of-the-art MILP solver to automatically generate observing plan timelines that achieve high probabilities of kilonova detection. We have implemented this strategy in an open-source astronomical scheduling software package called Multi-Mission Multi-Messenger Observation Planning Toolkit, on GitHub at https://github.com/m4opt/m4opt.
",
"date": "2025-07",
"date_type": "published",
"publication": "Publications of the Astronomical Society of the Pacific",
"volume": "137",
"number": "7",
"publisher": "IOP Publishing",
"pagerange": "074501",
"issn": "0004-6280",
"official_url": "https://authors.library.caltech.edu/records/5p7gt-89g42",
"funders": {
"items": [
{
"grant_number": "PHY-2210452"
},
{
"grant_number": "PHY-2308862"
},
{
"grant_number": "PHY-2117997"
},
{
"grant_number": "2138259"
},
{
"grant_number": "2138286"
},
{
"grant_number": "2138307"
},
{
"grant_number": "2137603"
},
{
"grant_number": "2138296"
}
]
},
"other_numbering_system": {
"items": [
{
"id": "P2500008-v3",
"name": "LIGO"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "LIGO"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.1088/1538-3873/adcfc6",
"primary_object": {
"basename": "10.1088_1538-3873_adcfc6.pdf",
"url": "https://authors.library.caltech.edu/records/5p7gt-89g42/files/10.1088_1538-3873_adcfc6.pdf"
},
"related_objects": [
{
"basename": "paspadcfc6supp1.gif",
"url": "https://authors.library.caltech.edu/records/5p7gt-89g42/files/paspadcfc6supp1.gif"
},
{
"basename": "paspadcfc6supp2.gif",
"url": "https://authors.library.caltech.edu/records/5p7gt-89g42/files/paspadcfc6supp2.gif"
}
],
"pub_year": "2025",
"author_list": "Singer, Leo P.; Criswell, Alexander W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/fn109-6hz92",
"eprint_status": "archive",
"datestamp": "2025-06-06 14:23:31",
"lastmod": "2025-06-06 14:23:31",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Drake",
"given": "J. F."
},
"orcid": "0000-0002-9150-1841"
},
{
"name": {
"family": "Phan",
"given": "T."
},
"orcid": "0000-0002-6924-9408"
},
{
"name": {
"family": "Yin",
"given": "Z."
},
"orcid": "0009-0009-7643-6103"
},
{
"name": {
"family": "Swisdak",
"given": "M."
},
"orcid": "0000-0001-9898-464X"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Rahmati",
"given": "A."
},
"orcid": "0000-0003-0519-6498"
},
{
"name": {
"family": "Larson",
"given": "D."
},
"orcid": "0000-0001-5030-6030"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "Dayeh",
"given": "M. A."
},
"orcid": "0000-0001-9323-1200"
},
{
"name": {
"family": "Starkey",
"given": "M. J."
},
"orcid": "0000-0001-7514-6571"
},
{
"name": {
"family": "Raouafi",
"given": "N. E."
},
"orcid": "0000-0003-2409-3742"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Malandraki",
"given": "O."
},
"orcid": "0000-0002-4751-6835"
},
{
"name": {
"family": "Whittlesey",
"given": "P."
},
"orcid": "0000-0002-7287-5098"
},
{
"name": {
"family": "Livi",
"given": "R."
},
"orcid": "0000-0002-0396-0547"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
}
]
},
"title": "Magnetic Reconnection\u2013driven Energization of Protons up to \u223c400 keV at the Near-Sun Heliospheric Current Sheet",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar magnetic reconnection",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThis work was supported by NASA's Parker Solar Probe Mission, contract NNN06AA01C. We thank all the scientists and engineers who have worked hard to make PSP a successful mission, particularly the engineers, scientists, and administrators who designed and built the IS\u2299IS/EPI-Lo, IS\u2299IS/EPI-Hi, FIELDS, and SWEAP instrument suites and who supported their operations and the scientific analysis of the data. For their contributions to the scientific configuration and instrumental analysis, we owe special thanks to P. Kollmann, J. Peachy, and J. Vandegriff at JHU/APL for EPI-Lo. PSP data are available at the NASA Space Physics Data Facility. Work at SwRI is supported in part by NASA grants 80NSSC20K1815, 80NSSC18K1446, 80NSSC21K0112, 80NSSC20K1255, and 80NSSC21K0971. W.H.M. is partially supported by the PSP/IS\u2299IS project at the University of Delaware subcontract SUB0000317 from Princeton University and by NASA PSP Guest Investigator grant 80NSSC21K1765.
",
"abstract": "\n
We report observations of direct evidence of energetic protons being accelerated above ∼400 keV within the reconnection exhaust of a heliospheric current sheet (HCS) crossing by NASA's Parker Solar Probe (PSP) at a distance of ∼16.25 solar radii (Rs) from the Sun. Inside the exhaust, both the reconnection-generated plasma jet and the accelerated protons up to ∼400 keV propagated toward the Sun, unambiguously establishing their origin from HCS reconnection sites located antisunward of PSP. Within the core of the exhaust, PSP detected stably trapped energetic protons up to ∼400 keV, which is ≈1000 times greater than the available magnetic energy per particle. The differential energy spectrum of the accelerated protons behaved as a pure power law with spectral index of ∼−5. Supporting simulations using the kglobal model suggest that the trapping and acceleration of protons up to ∼400 keV in the reconnection exhaust are likely facilitated by merging magnetic islands with a guide field between ∼0.2 and 0.3 of the reconnecting magnetic field, consistent with the observations. These new results, enabled by PSP's proximity to the Sun, demonstrate that magnetic reconnection in the HCS is a significant new source of energetic particles in the near-Sun solar wind. Our findings of in situ particle acceleration via magnetic reconnection at the HCS provide valuable insights into this fundamental process, which frequently converts the large magnetic field energy density in the near-Sun plasma environment and may be responsible for heating the Sun's atmosphere, accelerating the solar wind, and energizing charged particles to extremely high energies in solar flares.
\n
© The Author(s), under exclusive licence to Springer Nature Limited 2025.
\n\n\n
\n
We acknowledge funding from ANID programmes: Millennium Science Initiative Program NCN2023_002 (L.H.-G., J. Cuadra, P.A., S.B., M.L.M.-A.), Millennium Science Initiative, AIM23-0001 (L.H.-G., F.E.B., M.L.M.-A.), ANID-Chile BASAL CATA FB210003 (R.J.A., F.E.B., C.R.), FONDECYT Iniciación 11241477 (L.H.-G.), FONDECYT Regular 1211429 (J. Cuadra), FONDECYT Regular 1241422 (P.A., B.S.), FONDECYT Regular 1231718 (R.J.A.), FONDECYT Regular 1241005 (F.E.B.), Fondecyt Regular 1230345 (C.R.) and Programa de Becas/Doctorado Nacional 21212344 (S.B.). C.R. acknowledges support from the China–Chile joint research fund. A.B. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC 2094-390783311. K.E.S.F. and B.M. are supported by NSF AST-1831415, NSF AST-2206096 and Simons Foundation grant 533845. R.A. was supported by NASA through the NASA Hubble Fellowship grant HST-HF2-51499.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. A.G. is grateful for support from the Forrest Research Foundation. D.H. is supported by DLR grant FZK 50 OR 2406. M.K. acknowledges support from DLR grant FKZ 50 OR 2307. We acknowledge the use of public data from the Swift data archive through ToO proposals. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research has made use of data obtained from the Chandra Data Archive provided by the Chandra X-ray Center (CXC). This work is supported by NASA through the NICER mission and the Astrophysics Explorers Program and uses data and software provided by the High Energy Astrophysics Science Archive Research Center, which is a service of the Astrophysics Science Division at NASA/GSFC and High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. The scientific results reported in this work are based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work is based on data from eROSITA, the soft X-ray instrument aboard SRG, a joint Russian–German science mission supported by the Russian Space Agency (Roskosmos), in the interests of the Russian Academy of Sciences represented by its Space Research Institute (IKI), and the Deutsches Zentrum für Luft- und Raumfahrt (DLR). The SRG spacecraft was built by Lavochkin Association (NPOL) and its subcontractors, and is operated by NPOL with support from the Max Planck Institute for Extraterrestrial Physics (MPE). The development and construction of the eROSITA X-ray instrument was led by MPE, with contributions from the Dr. Karl Remeis Observatory Bamberg and ECAP (FAU Erlangen-Nuernberg), the University of Hamburg Observatory, the Leibniz Institute for Astrophysics Potsdam (AIP) and the Institute for Astronomy and Astrophysics of the University of Tübingen, with the support of DLR and the Max Planck Society. The Argelander Institute for Astronomy of the University of Bonn and the Ludwig Maximilians Universität Munich also participated in the science preparation for eROSITA. Part of this work is based on observations obtained with the Samuel Oschin Telescope 48-in. and the 60-in. Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under grant AST-2034437 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories and IN2P3, France. Operations are conducted by COO, IPAC and UW. The Australia Telescope Compact Array is part of the Australia Telescope National Facility, which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We thank the staff of the GMRT that made these observations possible. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. This scientific work uses data obtained from Inyarrimanha Ilgari Bundara/the Murchison Radio-astronomy Observatory. We acknowledge the Wajarri Yamaji People as the Traditional Owners and native title holders of the observatory site. CSIRO’s ASKAP radio telescope is part of the Australia Telescope National Facility (https://ror.org/05qajvd42). Operation of ASKAP is funded by the Australian Government with support from the National Collaborative Research Infrastructure Strategy. ASKAP uses the resources of the Pawsey Supercomputing Research Centre. Establishment of ASKAP, Inyarrimanha Ilgari Bundara, the CSIRO Murchison Radio-astronomy Observatory and the Pawsey Supercomputing Research Centre are initiatives of the Australian Government, with support from the Government of Western Australia and the Science and Industry Endowment Fund. This paper includes archived data obtained through the CSIRO ASKAP Science Data Archive, CASDA. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. CIRADA is funded by a grant from the Canada Foundation for Innovation 2017 Innovation Fund (project 35999), as well as by the Provinces of Ontario, British Columbia, Alberta, Manitoba and Quebec. Part of this work was carried out using the Web Interface from the ALeRCE broker.
\n
\n
\n
\n
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request. With the exception of eROSITA proprietary data, the raw data of the X-ray satellites are available from public archives. In this work we used the following X-ray observations: Swift ObsIDs 00014350001-00014350039, Chandra obsID 29355, NICER ObsIDs 7204490101–7204490160 and XMM-Newton ObsIDs 0935191401–0935191601.
\n
\n
Extended Data Fig. 1 Long term light curve of ZTF 19acnskyy.
\nExtended Data Fig. 2 XMM-Newton light curves.
\nExtended Data Fig. 3 Spectral fit of ObsID 935191501 of XMM-Newton.
\nExtended Data Fig. 4 Residuals of the spectral fits of the phase-resolved XMM-Newton data using the model tbabs*zbbody.
\nExtended Data Fig. 5 Spectral fits of the phase-resolved XMM-Newton data using the model tbabs*gabs*zbbody.
\nExtended Data Fig. 6 Swift/UVOT light curves.
\nExtended Data Fig. 7 Parameter space of disk and EMRI eccentricities for the case of an EMRI crossing the disk plane at pericentre.
\nExtended Data Fig. 8 Cumulative flux density emitted by a standard accretion disk as a function of outer truncation radius.
",
"abstract": "Quasi-periodic eruptions (QPEs) are rapid, recurring X-ray bursts from supermassive black holes, believed to result from interactions between accretion disks and surrounding matter. The galaxy SDSS1335+0728, previously stable for two decades, exhibited an increase in optical brightness in December 2019, followed by persistent active galactic nucleus (AGN)-like variability for 5 yr, suggesting the activation of a ~106-M\u2299 black hole. Since February 2024, X-ray emission has been detected, revealing extreme ~4.5-d QPEs with high fluxes and amplitudes, long timescales, large integrated energies and a ~25-d superperiod. Low-significance UV variations are reported, probably related to the long timescales and large radii from which the emission originates. This discovery broadens the possible formation channels for QPEs, suggesting that they are linked not solely to tidal disruption events but more generally to newly formed accretion flows, which we are witnessing in real time in a turn-on AGN candidate.
",
"date": "2025-06",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "9",
"number": "6",
"publisher": "Nature Publishing Group",
"pagerange": "895-906",
"issn": "2397-3366",
"official_url": "https://authors.library.caltech.edu/records/6qs87-63c17",
"funders": {
"items": [
{
"grant_number": "NCN2023_002"
},
{
"grant_number": "AIM23-0001"
},
{
"grant_number": "FB210003"
},
{
"grant_number": "11241477"
},
{
"grant_number": "1211429"
},
{
"grant_number": "1241422"
},
{
"grant_number": "1231718"
},
{
"grant_number": "1241005"
},
{
"grant_number": "1230345"
},
{
"grant_number": "21212344"
},
{},
{
"grant_number": "EXC 2094-390783311"
},
{
"grant_number": "AST-1831415"
},
{
"grant_number": "AST-2206096"
},
{
"grant_number": "533845"
},
{
"grant_number": "HST-HF2-51499.001-A"
},
{
"grant_number": "NAS5-26555"
},
{},
{
"grant_number": "FZK 50 OR 2406"
},
{
"grant_number": "FKZ 50 OR 2307"
},
{
"grant_number": "AST-2034437"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1038/s41550-025-02523-9",
"pub_year": "2025",
"author_list": "Hern\u00e1ndez-Garc\u00eda, Lorena; Chakraborty, Joheen; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5ck7n-nfy18",
"eprint_status": "archive",
"datestamp": "2025-05-19 22:20:20",
"lastmod": "2026-02-04 00:47:47",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Audard",
"given": "Marc"
},
"orcid": "0000-0003-4721-034X"
},
{
"name": {
"family": "Awaki",
"given": "Hisamitsu"
}
},
{
"name": {
"family": "Ballhausen",
"given": "Ralf"
}
},
{
"name": {
"family": "Bamba",
"given": "Aya"
},
"orcid": "0000-0003-0890-4920"
},
{
"name": {
"family": "Behar",
"given": "Ehud"
},
"orcid": "0000-0001-9735-4873"
},
{
"name": {
"family": "Boissay-Malaquin",
"given": "Rozenn"
},
"orcid": "0000-0003-2704-599X"
},
{
"name": {
"family": "Brenneman",
"given": "Laura"
}
},
{
"name": {
"family": "Brown",
"given": "Gregory V."
}
},
{
"name": {
"family": "Corrales",
"given": "Lia"
}
},
{
"name": {
"family": "Costantini",
"given": "Elisa"
},
"orcid": "0000-0001-8470-749X"
},
{
"name": {
"family": "Cumbee",
"given": "Renata"
},
"orcid": "0000-0001-9894-295X"
},
{
"name": {
"family": "Trigo",
"given": "Mar\u00eda D\u00edaz"
},
"orcid": "0000-0001-7796-4279"
},
{
"name": {
"family": "Done",
"given": "Chris"
},
"orcid": "0000-0002-1065-7239"
},
{
"name": {
"family": "Dotani",
"given": "Tadayasu"
}
},
{
"name": {
"family": "Ebisawa",
"given": "Ken"
}
},
{
"name": {
"family": "Eckart",
"given": "Megan"
},
"orcid": "0000-0003-3894-5889"
},
{
"name": {
"family": "Eckert",
"given": "Dominique"
}
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
}
},
{
"name": {
"family": "Eguchi",
"given": "Satoshi"
},
"orcid": "0000-0003-2814-9336"
},
{
"name": {
"family": "Ezoe",
"given": "Yuichiro"
}
},
{
"name": {
"family": "Foster",
"given": "Adam"
}
},
{
"name": {
"family": "Fujimoto",
"given": "Ryuichi"
},
"orcid": "0000-0002-2374-7073"
},
{
"name": {
"family": "Fujita",
"given": "Yutaka"
},
"orcid": "0000-0003-0058-9719"
},
{
"name": {
"family": "Fukazawa",
"given": "Yasushi"
}
},
{
"name": {
"family": "Fukushima",
"given": "Kotaro"
},
"orcid": "0000-0001-8055-7113"
},
{
"name": {
"family": "Furuzawa",
"given": "Akihiro"
}
},
{
"name": {
"family": "Gallo",
"given": "Luigi"
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
}
},
{
"name": {
"family": "Gu",
"given": "Liyi"
}
},
{
"name": {
"family": "Guainazzi",
"given": "Matteo"
}
},
{
"name": {
"family": "Hagino",
"given": "Kouichi"
},
"orcid": "0000-0003-4235-5304"
},
{
"name": {
"family": "Hamaguchi",
"given": "Kenji"
},
"orcid": "0000-0001-7515-2779"
},
{
"name": {
"family": "Hatsukade",
"given": "Isamu"
}
},
{
"name": {
"family": "Hayashi",
"given": "Katsuhiro"
}
},
{
"name": {
"family": "Hayashi",
"given": "Takayuki"
},
"orcid": "0000-0001-6665-2499"
},
{
"name": {
"family": "Hell",
"given": "Natalie"
},
"orcid": "0000-0003-3057-1536"
},
{
"name": {
"family": "Hodges-Kluck",
"given": "Edmund"
}
},
{
"name": {
"family": "Hornschemeier",
"given": "Ann"
}
},
{
"name": {
"family": "Ichinohe",
"given": "Yuto"
},
"orcid": "0000-0002-6102-1441"
},
{
"name": {
"family": "Ishida",
"given": "Manabu"
}
},
{
"name": {
"family": "Ishikawa",
"given": "Kumi"
}
},
{
"name": {
"family": "Ishisaki",
"given": "Yoshitaka"
}
},
{
"name": {
"family": "Kaastra",
"given": "Jelle"
},
"orcid": "0000-0001-5540-2822"
},
{
"name": {
"family": "Kallman",
"given": "Timothy"
}
},
{
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"name": {
"family": "Katsuda",
"given": "Satoru"
}
},
{
"name": {
"family": "Kanemaru",
"given": "Yoshiaki"
},
"orcid": "0000-0002-4541-1044"
},
{
"name": {
"family": "Kelley",
"given": "Richard"
}
},
{
"name": {
"family": "Kilbourne",
"given": "Caroline"
}
},
{
"name": {
"family": "Kitamoto",
"given": "Shunji"
}
},
{
"name": {
"family": "Kobayashi",
"given": "Shogo"
}
},
{
"name": {
"family": "Kohmura",
"given": "Takayoshi"
},
"orcid": "0000-0003-4403-4512"
},
{
"name": {
"family": "Kubota",
"given": "Aya"
}
},
{
"name": {
"family": "Leutenegger",
"given": "Maurice"
},
"orcid": "0000-0002-3331-7595"
},
{
"name": {
"family": "Loewenstein",
"given": "Michael"
},
"orcid": "0000-0002-1661-4029"
},
{
"name": {
"family": "Maeda",
"given": "Yoshitomo"
}
},
{
"name": {
"family": "Markevitch",
"given": "Maxim"
}
},
{
"name": {
"family": "Matsumoto",
"given": "Hironori"
}
},
{
"name": {
"family": "Matsushita",
"given": "Kyoko"
}
},
{
"name": {
"family": "McCammon",
"given": "Dan"
},
"orcid": "0000-0001-5170-4567"
},
{
"name": {
"family": "McNamara",
"given": "Brian"
}
},
{
"name": {
"family": "Mernier",
"given": "Fran\u00e7ois"
}
},
{
"name": {
"family": "Miller",
"given": "Eric D."
},
"orcid": "0000-0002-3031-2326"
},
{
"name": {
"family": "Miller",
"given": "Jon M."
},
"orcid": "0000-0003-2869-7682"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Mizumoto",
"given": "Misaki"
},
"orcid": "0000-0003-2161-0361"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Mori",
"given": "Koji"
},
"orcid": "0000-0002-0018-0369"
},
{
"name": {
"family": "Mukai",
"given": "Koji"
},
"orcid": "0000-0002-8286-8094"
},
{
"name": {
"family": "Murakami",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Nakajima",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Nakazawa",
"given": "Kazuhiro"
}
},
{
"name": {
"family": "Ness",
"given": "Jan-Uwe"
}
},
{
"name": {
"family": "Nobukawa",
"given": "Kumiko"
}
},
{
"name": {
"family": "Nobukawa",
"given": "Masayoshi"
}
},
{
"name": {
"family": "Noda",
"given": "Hirofumi"
}
},
{
"name": {
"family": "Odaka",
"given": "Hirokazu"
}
},
{
"name": {
"family": "Ogawa",
"given": "Shoji"
}
},
{
"name": {
"family": "Ogorzalek",
"given": "Anna"
}
},
{
"name": {
"family": "Okajima",
"given": "Takashi"
},
"orcid": "0000-0002-6054-3432"
},
{
"name": {
"family": "Ota",
"given": "Naomi"
},
"orcid": "0000-0002-2784-3652"
},
{
"name": {
"family": "Paltani",
"given": "Stephane"
}
},
{
"name": {
"family": "Petre",
"given": "Robert"
}
},
{
"name": {
"family": "Plucinsky",
"given": "Paul"
}
},
{
"name": {
"family": "Porter",
"given": "Frederick Scott"
},
"orcid": "0000-0002-6374-1119"
},
{
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
},
{
"name": {
"family": "Sato",
"given": "Kosuke"
},
"orcid": "0000-0001-5774-1633"
},
{
"name": {
"family": "Sato",
"given": "Toshiki"
}
},
{
"name": {
"family": "Sawada",
"given": "Makoto"
}
},
{
"name": {
"family": "Seta",
"given": "Hiromi"
}
},
{
"name": {
"family": "Shidatsu",
"given": "Megumi"
},
"orcid": "0000-0001-8195-6546"
},
{
"name": {
"family": "Simionescu",
"given": "Aurora"
},
"orcid": "0000-0002-9714-3862"
},
{
"name": {
"family": "Smith",
"given": "Randall"
},
"orcid": "0000-0003-4284-4167"
},
{
"name": {
"family": "Suzuki",
"given": "Hiromasa"
}
},
{
"name": {
"family": "Szymkowiak",
"given": "Andrew"
}
},
{
"name": {
"family": "Takahashi",
"given": "Hiromitsu"
},
"orcid": "0000-0001-6314-5897"
},
{
"name": {
"family": "Takeo",
"given": "Mai"
}
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tamura",
"given": "Keisuke"
},
"orcid": "0000-0002-6677-3917"
},
{
"name": {
"family": "Tanaka",
"given": "Takaaki"
},
"orcid": "0000-0002-4383-0368"
},
{
"name": {
"family": "Tanimoto",
"given": "Atsushi"
}
},
{
"name": {
"family": "Tashiro",
"given": "Makoto"
},
"orcid": "0000-0002-5097-1257"
},
{
"name": {
"family": "Terada",
"given": "Yukikatsu"
},
"orcid": "0000-0002-2359-1857"
},
{
"name": {
"family": "Terashima",
"given": "Yuichi"
}
},
{
"name": {
"family": "Tsuboi",
"given": "Yohko"
}
},
{
"name": {
"family": "Tsujimoto",
"given": "Masahiro"
}
},
{
"name": {
"family": "Tsunemi",
"given": "Hiroshi"
}
},
{
"name": {
"family": "Tsuru",
"given": "Takeshi G."
},
"orcid": "0000-0002-5504-4903"
},
{
"name": {
"family": "Uchida",
"given": "Hiroyuki"
}
},
{
"name": {
"family": "Uchida",
"given": "Nagomi"
}
},
{
"name": {
"family": "Uchida",
"given": "Yuusuke"
},
"orcid": "0000-0002-7962-4136"
},
{
"name": {
"family": "Uchiyama",
"given": "Hideki"
},
"orcid": "0000-0003-4580-4021"
},
{
"name": {
"family": "Ueda",
"given": "Yoshihiro"
}
},
{
"name": {
"family": "Uno",
"given": "Shinichiro"
}
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Watanabe",
"given": "Shin"
},
"orcid": "0000-0003-0441-7404"
},
{
"name": {
"family": "Williams",
"given": "Brian J."
},
"orcid": "0000-0003-2063-381X"
},
{
"name": {
"family": "Yamada",
"given": "Satoshi"
}
},
{
"name": {
"family": "Yamada",
"given": "Shinya"
},
"orcid": "0000-0003-4808-893X"
},
{
"name": {
"family": "Yamaguchi",
"given": "Hiroya"
}
},
{
"name": {
"family": "Yamaoka",
"given": "Kazutaka"
}
},
{
"name": {
"family": "Yamasaki",
"given": "Noriko"
},
"orcid": "0000-0003-4885-5537"
},
{
"name": {
"family": "Yamauchi",
"given": "Makoto"
},
"orcid": "0000-0003-1100-1423"
},
{
"name": {
"family": "Yamauchi",
"given": "Shigeo"
}
},
{
"name": {
"family": "Yaqoob",
"given": "Tahir"
}
},
{
"name": {
"family": "Yoneyama",
"given": "Tomokage"
}
},
{
"name": {
"family": "Yoshida",
"given": "Tessei"
}
},
{
"name": {
"family": "Yukita",
"given": "Mihoko"
}
},
{
"name": {
"family": "Zhuravleva",
"given": "Irina"
},
"orcid": "0000-0001-7630-8085"
},
{
"name": {
"family": "Braito",
"given": "Valentina"
}
},
{
"name": {
"family": "Cond\u00f2",
"given": "Pierpaolo"
},
"orcid": "0009-0005-9183-8662"
},
{
"name": {
"family": "Fukumura",
"given": "Keigo"
},
"orcid": "0000-0001-5709-7606"
},
{
"name": {
"family": "Gonzalez",
"given": "Adam"
},
"orcid": "0000-0003-3678-5033"
},
{
"name": {
"family": "Luminari",
"given": "Alfredo"
}
},
{
"name": {
"family": "Miyamoto",
"given": "Aiko"
}
},
{
"name": {
"family": "Mizukawa",
"given": "Ryuki"
}
},
{
"name": {
"family": "Reeves",
"given": "James"
},
"orcid": "0000-0002-0982-0561"
},
{
"name": {
"family": "Sato",
"given": "Riki"
},
"orcid": "0009-0002-6943-8169"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Xu",
"given": "Yerong"
}
}
]
},
"title": "Structured ionized winds shooting out from a quasar at relativistic speeds",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Compact astrophysical objects; High-energy astrophysics",
"note": "© 2025, The Author(s), under exclusive licence to Springer Nature Limited.
\n\nWe thank J. Mao for fruitful discussions and comments and Y. Mochizuki for his technical advice on XSTAR table models. This work was supported by JSPS KAKENHI grant numbers JP22H00158, JP22H01268, JP22K03624, JP23H04899, JP21K13963, JP24K00638, JP24K17105, JP21K13958, JP21H01095, JP23K20850, JP24H00253, JP21K03615, JP24K00677, JP20K14491, JP23H00151, JP19K21884, JP20H01947, JP20KK0071, JP23K20239, JP24K00672, JP24K17104, JP24K17093, JP20K04009, JP21H04493, JP20H01946, JP23K13154, JP19K14762 and JP20H05857, JP2 Examples of the convolved emission line p3K03459 and NASA grant numbers 80NSSC24K1148, 80NSSC24K1774, 80NSSC20K0733, 80NSSC18K0978, 80NSSC20K0883, 80NSSC20K0737, 80NSSC24K0678, 80NSSC18K1684 and 80NNSC22K1922. M. Mizumoto acknowledges support from Yamada Science Foundation. L.C. acknowledges support from NSF award 2205918. C.D. acknowledges support from STFC through grant ST/T000244/1 and a Leverhulme Trust International Fellowship. L. Gallo acknowledges financial support from Canadian Space Agency grant 18XARMSTMA. A.T. is supported in part by the Kagoshima University postdoctoral research programme (KU-DREAM). Satoshi Yamada acknowledges support by the RIKEN SPDR Program. I.Z. acknowledges partial support from the Alfred P. Sloan Foundation through the Sloan Research Fellowship. F.T. acknowledges funding from the European Union – Next Generation EU, PRIN/MUR 2022 (2022K9N5B4). J.R. acknowledges support from NASA XRISM grant 80NSSC23K0645. Part of this work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. The material is based on work supported by NASA under award number 80GSFC21M0002. This work has been partially supported by the ASI-INAF programme I/004/11/6. This work was supported by the JSPS Core-to-Core Program, JPJSCCA20220002. The material is based on work supported by the Strategic Research Center of Saitama University.
\n\nThe observational data analysed during this study will be available at NASA’s High Energy Astrophysics Science Archive Research Center (HEASARC; https://heasarc.gsfc.nasa.gov/) in the summer of 2025.
\n\nThe codes used for the data reduction are available from the HEASARC website (https://heasarc.gsfc.nasa.gov/docs/software/heasoft) and the ESA’s website (https://www.cosmos.esa.int/web/xmm-newton/sas). The spectral fitting tools are freely available online (https://heasarc.gsfc.nasa.gov/xanadu/xspec for XSPEC and https://www.sron.nl/astrophysics-spex for SPEX).
\n\nSupplementary Information
\n\n
This file contains Supplementary Methods 1–4, Supplementary References, Supplementary Figs. 1–8 and Supplementary Tables 1–4.
\n
© 2025. The Author(s). Published by the American Astronomical Society.
\n\n
\n
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n
\n
This work is based on observations carried out under project No. d23ab with the IRAM NOEMA Interferometer [30 m telescope]. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain). The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. We thank the staff of the GMRT that made these observations possible. The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (Caltech, USA). Partially based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This paper employs a list of Chandra data sets, obtained by the Chandra X-ray Observatory, contained in doi:10.25574/cdc.351. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research has made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
\nThis work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-2210452. The collaboration of D.T. and R.M. was facilitated by interactions that were funded by the Gordon and Betty Moore Foundation through grant GBMF5076. R.M. acknowledges support by the National Science Foundation under award No. AST-2221789 and AST-2224255, and by NASA under grant 80NSSC22K1587. The TReX team at UC Berkeley is partially funded by the Heising-Simons Foundation under grant 2021-3248 (PI: Margutti). The work of K.M. is partially supported by the NSF grants No. AST-2108466, No. AST-2108467, and No. AST-2308021, and KAKENHI No. 20H05852. D.T. acknowledges support by the Sherman Fairchild Postdoctoral Fellowship at the California Institute of Technology. P.C. acknowledges support from NASA through Chandra award No. DD3-24141X issued by the Chandra X-ray Center. K.M. acknowledges support from the Japan Society for the Promotion of Science (JSPS) KAKENHI grant JP24KK0070 and 24H01810. F.D.C. acknowledges support from DGAPA/PAPIIT grant IN113424. Andrea Reguitti acknowledges financial support from the GRAWITA Large Program grant (PI P. D'Avanzo) and the PRIN-INAF 2022 \"Shedding light on the nature of gap transients: from the observations to the models\". G.M. acknowledges financial support from the INAF mini-grant \"The high-energy view of jets and transients\" (Bando Ricerca Fondamentale INAF 2022). S.C. thanks Norbert Schartel for granting the first XMM-Newton observation. S.C. acknowledges support from ASI. B.M. acknowledges financial support from the State Agency for Research of the Spanish Ministry of Science and Innovation, and FEDER, UE, under grant PID2022-136828NB-C41/MICIU/AEI/10.13039/501100011033, and through the Unit of Excellence Marìa de Maeztu 2020–2023 award to the Institute of Cosmos Sciences (CEX2019- 000918-M). The European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program ('EuroFlash': grant agreement No. 101098079).
\n\nHST - Hubble Space Telescope satellite (STIS), Swift - Swift Gamma-Ray Burst Mission (XRT and UVOT), AAVSO - American Association of Variable Star Observers International Database, CTIO:1.3m - Cerro Tololo Inter-American Observatory's 1.3 meter Telescope, CTIO:1.5m - Cerro Tololo Inter-American Observatory's 1.5 meter Telescope, CXO - Chandra X-ray Observatory satellite.
\n\nastropy (Astropy Collaboration et al. 2013, 2018).
\n\nThe title was inspired by a news report on the rediscovery of fossilized dinosaur eggs in rural Gujarat in Indian Express 2024 October 28.
",
"abstract": "We present the results from our extensive hard-to-soft X-ray (NuSTAR, Swift-XRT, XMM-Newton, Chandra) and meter-to-millimeter-wave radio (Giant Metrewave Radio Telescope, Very Large Array, NOEMA) monitoring campaign of the very nearby (d = 6.9 Mpc) Type II supernova (SN) 2023ixf spanning ≈4–165 days post-explosion. This unprecedented data set enables inferences on the explosion's circumstellar medium (CSM) density and geometry. In particular, we find that the luminous X-ray emission is well modeled by thermal free–free radiation from the forward shock with rapidly decreasing photoelectric absorption with time. The radio spectrum is dominated by synchrotron radiation from the same shock. Similar to the X-rays, the level of free–free absorption affecting the radio spectrum rapidly decreases with time as a consequence of the shock propagation into the dense CSM. While the X-ray and the radio modeling independently support the presence of a dense medium corresponding to an effective mass-loss rate M\u02d9≈10−\u2074M\u2299yr−1 at R = (0.4–14) × 1015 cm (for vw = 25 km s−1), our study points at a complex CSM density structure with asymmetries and clumps. The inferred densities are ≈10–100 times those of typical red supergiants, indicating an extreme mass-loss phase of the progenitor in the ≈200 yr preceding core collapse, which leads to the most X-ray luminous Type II SN and the one with the most delayed emergence of radio emission. These results add to the picture of the complex mass-loss history of massive stars on the verge of collapse and demonstrate the need for panchromatic campaigns to fully map their intricate environments.
",
"date": "2025-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "985",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "51",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/fkkfq-qdb29",
"funders": {
"items": [
{
"grant_number": "PHY-2210452"
},
{
"grant_number": "GBMF5076"
},
{
"grant_number": "AST-2221789"
},
{
"grant_number": "AST-2224255"
},
{
"grant_number": "80NSSC22K1587"
},
{
"grant_number": "2021-3248"
},
{
"grant_number": "AST-2108466"
},
{
"grant_number": "AST-2108467"
},
{
"grant_number": "AST-2308021"
},
{
"grant_number": "20H05852"
},
{},
{
"grant_number": "DD3-24141X"
},
{
"grant_number": "JP24KK0070"
},
{
"grant_number": "24H01810"
},
{
"grant_number": "IN113424"
},
{
"grant_number": "-"
},
{
"grant_number": "PRIN-INAF 2022"
},
{},
{
"grant_number": "PID2022-136828NB-C41"
},
{
"grant_number": "CEX2019-000918-M"
},
{
"grant_number": "101098079"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "TAPIR"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4357/adc2fb",
"primary_object": {
"basename": "A_J_2025_ApJ_985_51.pdf",
"url": "https://authors.library.caltech.edu/records/fkkfq-qdb29/files/A_J_2025_ApJ_985_51.pdf"
},
"pub_year": "2025",
"author_list": "A. J., Nayana; Margutti, Raffaella; et al."
},
{
"id": "https://authors.library.caltech.edu/records/qwsnd-jmx38",
"eprint_status": "archive",
"datestamp": "2025-05-29 17:58:41",
"lastmod": "2025-05-29 17:58:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Liu",
"given": "Weihao"
},
"orcid": "0000-0002-2873-5688"
},
{
"name": {
"family": "Sokolov",
"given": "Igor V."
},
"orcid": "0000-0002-6118-0469"
},
{
"name": {
"family": "Zhao",
"given": "Lulu"
},
"orcid": "0000-0003-3936-5288"
},
{
"name": {
"family": "Gombosi",
"given": "Tamas I."
},
"orcid": "0000-0001-9360-4951"
},
{
"name": {
"family": "Sachdeva",
"given": "Nishtha"
},
"orcid": "0000-0001-9114-6133"
},
{
"name": {
"family": "Chen",
"given": "Xiaohang"
},
"orcid": "0000-0003-2865-1772"
},
{
"name": {
"family": "T\u00f3th",
"given": "G\u00e1bor"
},
"orcid": "0000-0001-8459-2100"
},
{
"name": {
"family": "Lario",
"given": "David"
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Manchester",
"given": "Ward B."
},
"orcid": "0000-0003-0472-9408"
},
{
"name": {
"family": "Whitman",
"given": "Kathryn"
},
"orcid": "0000-0002-3787-1622"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Bruno",
"given": "Alessandro"
},
"orcid": "0000-0001-5191-1662"
},
{
"name": {
"family": "Mays",
"given": "M. Leila"
},
"orcid": "0000-0001-9177-8405"
},
{
"name": {
"family": "Bain",
"given": "Hazel M."
},
"orcid": "0000-0003-2595-3185"
}
]
},
"title": "Physics-based Simulation of the 2013 April 11 Solar Energetic Particle Event",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar coronal mass ejection shocks; Heliosphere; Space weather; Computational methods",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\n\n
\n
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n
\n
\n
The authors sincerely thank the anonymous reviewer for the time and effort devoted to improving this paper. This work is supported by NASA Living With a Star (LWS) Strategic Capability project under NASA grant 80NSSC22K0892 (SCEPTER), NASA Space Weather Center of Excellence program under award 80NSSC23M0191 (CLEAR), NASA grant 80NSSC21K1124, NSF ANSWERS grant GEO-2149771 and NASA LWS grant 80NSSC20K1778. Dr. Bruno also acknowledges support by NASA under award 80GSFC24M0006. The authors express their great gratitude to the SOHO project, an international cooperation between ESA and NASA, and to the SDO, STEREO, ACE, GOES, and PSP teams. The authors acknowledge the development of StereoCAT (see footnote 12) for CME analysis, as well as the DONKI (see footnote 13), CDAW (see footnote 14), and OMNI (see footnote 17) data sets. The authors also thank the Virtual Solar Observatory (VSO, see footnote 19) project at the National Solar Observatory (NSO), which serves as a research tool allowing scientists to search for the solar and heliospheric physics data. This work utilizes data from the NSO Integrated Synoptic Program, which is operated by the Association of Universities for Research in Astronomy, under a cooperative agreement with the National Science Foundation and with additional financial support from the National Oceanic and Atmospheric Administration, the National Aeronautics and Space Administration and the United States Air Force. The GONG (see footnote 10) network of instruments is hosted by the Big Bear Solar Observatory (USA), High Altitude Observatory (USA), Learmonth Solar Observatory (Australia), Udaipur Solar Observatory (India), Instituto de Astrofìsica de Canarias (Spain), and Cerro Tololo Inter-American Observatory (Chile). Computational resources supporting this work are provided by the NASA High-End Computing (HEC) Program21 through the NASA Advanced Supercomputing (NAS) Division at the Ames Research Center. Any opinions, findings, conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Aeronautics and Space Administration.
\n
Solar energetic particles (SEPs) can pose hazardous radiation risks to both humans and spacecraft electronics in space. Numerical modeling based on first principles offers valuable insights into the underlying physics of SEPs and provides synthetic observables for SEPs at any time and location in the inner heliosphere. In this work, we present a numerical scheme, which conserves the number of particles based on integral relations for Poisson brackets, to solve the kinetic equation for particle acceleration and transport processes. We implement this scheme within the Space Weather Modeling Framework, developed at the University of Michigan. In addition, we develop a new shock-capturing tool to study the coronal mass ejection-driven shock originating from the low solar corona. These methodological advancements are applied to conduct a comprehensive study of a historical SEP event on 2013 April 11. Observations from multiple spacecraft, including the Solar and Heliospheric Observatory, Solar Dynamics Observatory, Geostationary Operational Environmental Satellite, Advanced Composition Explorer near Earth, and STEREO-A/B, are used for model–data comparison and validation. We show synthetic observables, including extreme ultraviolet and white-light images, proton time–intensity profiles, and energy spectra, and discuss their differences and probable explanations compared to observations. Our simulation results demonstrate the application of the Poisson bracket scheme with a particle solver to simulating a historical SEP event. We also show the capability of extracting the complex shock surface using our shock-capturing tool and understand how the complex shock surface affects the particle acceleration process.
",
"date": "2025-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "985",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "82",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/qwsnd-jmx38",
"funders": {
"items": [
{
"grant_number": "80NSSC22K0892"
},
{
"grant_number": "80NSSC23M0191"
},
{
"grant_number": "80NSSC21K1124"
},
{
"grant_number": "GEO-2149771"
},
{
"grant_number": "80NSSC20K1778"
},
{
"grant_number": "80GSFC24M0006"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/adc4e3",
"primary_object": {
"basename": "Liu_2025_ApJ_985_82.pdf",
"url": "https://authors.library.caltech.edu/records/qwsnd-jmx38/files/Liu_2025_ApJ_985_82.pdf"
},
"pub_year": "2025",
"author_list": "Liu, Weihao; Sokolov, Igor V.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/106vk-sp171",
"eprint_status": "archive",
"datestamp": "2025-08-18 16:33:39",
"lastmod": "2025-08-18 16:33:39",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Shen",
"given": "M. M."
},
"orcid": "0000-0002-3093-458X"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Pokorn\u00fd",
"given": "P."
},
"orcid": "0000-0002-5667-9337"
},
{
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Malaspina",
"given": "D. M."
},
"orcid": "0000-0003-1191-1558"
}
]
},
"title": "Diverse Dust Populations in the Near-Sun Environment Characterized by PSP/IS\u0298IS",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Interplanetary dust; Meteoroids; Zodiacal cloud",
"note": "© 2025. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
We gratefully thank everyone who helped make the IS\u0298IS instrument suite and PSP mission possible. The PSP was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory (APL) as part of NASA’s Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the PSP mission. We acknowledge NASA PSP Guest Investigator grant (80NSSC21K1764). The modeling material is based upon work supported by NASA under awards number 80GSFC24M0006, 80NSSC21K0153, and ISFM work packages EIMM and Planetary Geodesy at NASA Goddard Space Flight Center. We sincerely appreciate Carol Weaver’s IS\u0298IS SOC role in providing first-glance dust impact alerts and attitude kernels for simulations in coordination with the PSP mission operation center at APL.
\n
\n
Conceptualization—J.R.S., M.M.S. Formal analysis—M.M.S., J.R.S., P.P., D.M. Funding acquisition—J.R.S., P.P., D.M. Investigation— M.M.S., J.R.S. Methodology –J.R.S., M.M.S. Validation—M.M.S., J.R.S., P.P., M.E.H., J.G.M., D.M. Writing—original draft—M.M.S., J.G.M., J.R.S. Writing—review & editing—M.M.S., J.R.S., J.G.M., P.P., D.J M., D.M., C.M.S.C.
\n
\n
\n
IS\u0298IS data and visualization tools are available at https://spacephysics.princeton.edu/missions-instruments/PSP; NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/); and IS\u0298IS science operation center (https://spp-isois.sr.unh.edu/home.html). The supplemental data in this study (M. Shen et al. 2024, Supporting Information data set) is publicly available on the Zenodo repository (doi:10.5281/zenodo.14548706).
\n
\n
The Integrated Science Investigation of the Sun energetic particle instrument suite on the Parker Solar Probe is dedicated to measuring energetic ions and electrons in the near-Sun environment. It includes a half-sky-viewing time-of-flight mass spectrometer (EPI-Lo) and five high-energy silicon solid-state detector-telescopes (EPI-Hi). To 2024 August, eight of EPI-Lo’s eighty separate telescope foils have experienced direct dust puncture events, most of which occurred inside 40 solar radii (0.19 au). These impacts represent the closest high-fidelity dust detections to the Sun. While there is limited information about the size/mass of each impact due to the lack of a dedicated dust instrument, we can determine the impact direction for six punctures, allowing us to partially constrain abundant dust populations in the inner zodiacal cloud. Remarkably, one of six unambiguous dust impactors was likely on a retrograde orbit, suggesting long-period cometary material may survive within 20 solar radii (0.09 au). We discuss observations in the context of highlighting multiple dust populations responsible for these events to improve our understanding of the zodiacal dust environment in the inner heliosphere (\u22721 au).
",
"date": "2025-05-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "984",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "165",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/106vk-sp171",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
},
{
"grant_number": "80NSSC21K1764"
},
{
"grant_number": "80GSFC24M0006"
},
{
"grant_number": "80NSSC21K0153"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/adc258",
"primary_object": {
"basename": "Shen_2025_ApJ_984_165.pdf",
"url": "https://authors.library.caltech.edu/records/106vk-sp171/files/Shen_2025_ApJ_984_165.pdf"
},
"pub_year": "2025",
"author_list": "Shen, M. M.; Szalay, J. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/akhtc-vqp38",
"eprint_status": "archive",
"datestamp": "2025-05-08 21:20:16",
"lastmod": "2026-03-10 00:34:14",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Criswell",
"given": "Alexander W."
},
"orcid": "0000-0002-9225-7756"
},
{
"name": {
"family": "Leggio",
"given": "Sydney C."
},
"orcid": "0009-0000-9360-4759"
},
{
"name": {
"family": "Coughlin",
"given": "Michael W."
},
"orcid": "0000-0002-8262-2924"
},
{
"name": {
"family": "Singer",
"given": "Leo P."
},
"orcid": "0000-0001-9898-5597"
},
{
"name": {
"family": "Kiendrebeogo",
"given": "R. Weizmann"
},
"orcid": "0000-0002-9108-5059"
},
{
"name": {
"family": "Andreoni",
"given": "Igor"
},
"orcid": "0000-0002-8977-1498"
},
{
"name": {
"family": "Toivonen",
"given": "Andrew"
},
"orcid": "0009-0008-9546-2035"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"name": {
"family": "Gezari",
"given": "Suvi"
},
"orcid": "0000-0003-3703-5154"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kasliwal-M-M",
"name": {
"family": "Kasliwal",
"given": "Mansi M."
},
"orcid": "0000-0002-5619-4938"
}
]
},
"title": "Electromagnetic Follow-up to Gravitational Wave Events with the UltraViolet EXplorer (UVEX)",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Ultraviolet transient sources; Gravitational wave astronomy",
"note": "© 2025. The Author(s). Published by IOP Publishing Ltd on behalf of the Astronomical Society of the Pacific (ASP).
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nPortions of this manuscript were adapted from the doctoral dissertation of A.W.C., Astrophysical Inferences from Multimessenger Ensembles. A.W.C. acknowledges support by NSF grant No. 2125764. M.W.C. acknowledges support from the National Science Foundation with grant Nos PHY-2308862 and PHY-2117997. The authors acknowledge the use of computing resources provided by the Minnesota Supercomputing Institute at the University of Minnesota. This work used the Delta CPU at University of Illinois at Urbana-Champaign National Center for Supercomputing Applications through allocation AST200029 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services and Support (ACCESS) program, which is supported by U.S. National Science Foundation grants Nos. 2138259, 2138286, 2138307, 2137603, and 2138296.
\n\nuvex-followup (https://github.com/criswellalexander/uvex-followup), dorado-scheduling (https://github.com/nasa/dorado-scheduling), uvex-mission (Grefenstette et al., private repository), BAYESTAR (Singer & Price 2016), Matplotlib (Hunter 2007), Numpy (Harris et al. 2020), Scipy (Virtanen et al. 2020), Python (Van Rossum & Drake 2009), Healpy (Zonca et al. 2019), Pandas (McKinney 2010), and Astropy (Robitaille et al. 2013; The Astropy Collaboration et al. 2018; Astropy Collaboration et al. 2022).
\n\n\n
The version of uvex-followup used for this study can be found on Zenodo (Criswell 2024). The data products created for this work are available on Zenodo (Leggio & Criswell 2024). The observing scenarios used in this work are publicly available; see Kiendrebeogo et al. (2023) and references therein.
\n
The Ultraviolet Explorer (UVEX) is expected to fly in 2030 and will have the opportunity—and the rapid near/far-ultraviolet (UV) capabilities—to glean unprecedented insight into the bright UV emission present in kilonovae like that of AT 170817gfo, the electromagnetic counterpart to binary neutron star merger GW170817. To do so, it will need to perform prompt target-of-opportunity observations following detection of binary neutron star mergers by the LIGO–Virgo–KAGRA gravitational observatories. We present initial simulations to develop UVEX target-of-opportunity strategies for such events and provide the community with detailed initial estimates of the prospects for and characteristics of UVEX target-of-opportunity observations following gravitational-wave events, considering fiducial scenarios for the fifth and sixth LIGO–Virgo–KAGRA observing runs. Additionally, in light of the relatively few binary neutron star mergers observed since GW170817, we consider variant target-of-opportunity strategies for UVEX to maximize scientific gain in the case of a lowered binary neutron star merger rate.
",
"date": "2025-05",
"date_type": "published",
"publication": "Publications of the Astronomical Society of the Pacific",
"volume": "137",
"number": "5",
"publisher": "IOP Publishing",
"pagerange": "054101",
"issn": "0004-6280",
"official_url": "https://authors.library.caltech.edu/records/akhtc-vqp38",
"funders": {
"items": [
{
"grant_number": "DGE-2125764"
},
{
"grant_number": "PHY-2308862"
},
{
"grant_number": "PHY-2117997"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.1088/1538-3873/adcd9c",
"primary_object": {
"basename": "Criswell_2025_PASP_137_054101.pdf",
"url": "https://authors.library.caltech.edu/records/akhtc-vqp38/files/Criswell_2025_PASP_137_054101.pdf"
},
"pub_year": "2025",
"author_list": "Criswell, Alexander W.; Leggio, Sydney C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/35w12-8p626",
"eprint_status": "archive",
"datestamp": "2025-05-13 18:39:09",
"lastmod": "2025-05-13 18:40:10",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kammoun-Elias",
"name": {
"family": "Kammoun",
"given": "E."
},
"orcid": "0000-0002-0273-218X"
},
{
"name": {
"family": "Papadakis",
"given": "I. E."
},
"orcid": "0000-0001-6264-140X"
},
{
"name": {
"family": "Dov\u010diak",
"given": "M."
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Lusso",
"given": "E."
},
"orcid": "0000-0003-0083-1157"
},
{
"name": {
"family": "Nardini",
"given": "E."
},
"orcid": "0000-0001-9226-8992"
},
{
"name": {
"family": "Risaliti",
"given": "G."
},
"orcid": "0000-0002-3556-977X"
}
]
},
"title": "Explaining the UV to X-ray correlation in active galactic nuclei within the framework of X-ray illumination of accretion discs",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion; accretion disks; galaxies: active; galaxies: nuclei; quasars: general; quasars: supermassive black holes",
"note": "© The Authors 2025.
\nOpen Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nWe thank the anonymous referee for their constructive feedback. EK and IEP acknowledge support from the European Union’s Horizon 2020 Programme under the AHEAD2020 project (grant agreement n. 871158).
\n\nSoftware packages used in this study include XSPEC/PyXSPEC (Arnaud 1996), NumPy (Harris et al. 2020), SciPy (Virtanen et al. 2020), Pandas (McKinney 2010), Matplotlib (Hunter 2007), and GetDist (Lewis 2019).
",
"abstract": "Context. It is established that the ultraviolet (UV) and X-ray emission in active galactic nuclei (AGN) is tightly correlated. This correlation is observed both in low- and high-redshift sources. In particular, observations of large samples of quasars revealed a non-linear correlation between UV and X-rays. The physical origin of this correlation is poorly understood.
\nAims. We explore this observed correlation in the framework of the X-ray illumination of the accretion disc by a central source. We showed previously that this model successfully explains the continuum UV/optical time delays, variability, and the broadband spectral energy distribution in AGN.
\nMethods. We used this model to produce 150 000 model spectral energy distributions, assuming a uniform distribution of the model parameters. We computed the corresponding UV (2500 Å) and X-ray (2 keV) monochromatic luminosities and selected only the model data points that agreed with the observed UV-to-X-ray correlation.
\nResults. Our results show that the X-ray illuminated accretion disc model can reproduce the observed correlation for a subset of model configurations with a non-uniform distribution of the black hole mass (MBH), accretion rate (\u1e41/\u1e41Edd), and power transferred from the accretion disc to the corona (Ltransf/Ldisc). In addition, our results reveal a correlation between MBH and \u1e41/\u1e41Edd and between \u1e41/\u1e41Edd and Ltransf/Ldisc that explains the observed X-ray-UV correlation. We also present evidence based on observed luminosities that supports our findings. We finally discuss the implications of our results.
",
"date": "2025-05",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "697",
"publisher": "EDP Sciences",
"pagerange": "A55",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/35w12-8p626",
"funders": {
"items": [
{
"grant_number": "871158"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1051/0004-6361/202452629",
"primary_object": {
"basename": "aa52629-24.pdf",
"url": "https://authors.library.caltech.edu/records/35w12-8p626/files/aa52629-24.pdf"
},
"pub_year": "2025",
"author_list": "Kammoun, E.; Papadakis, I. E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gh0bd-sme31",
"eprint_status": "archive",
"datestamp": "2025-04-16 22:33:58",
"lastmod": "2025-04-16 22:33:58",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Wang \u738b",
"given": "Meiqi \u7f8e\u797a"
},
"orcid": "0000-0002-2633-3562"
},
{
"name": {
"family": "Chen \u9648",
"given": "Bin \u5f6c"
},
"orcid": "0000-0002-0660-3350"
},
{
"name": {
"family": "Knuth",
"given": "Trevor"
},
"orcid": "0000-0002-4795-7059"
},
{
"id": "Cohen-Christina-M",
"name": {
"family": "Cohen",
"given": "Christina"
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Lee",
"given": "Jeongwoo"
},
"orcid": "0000-0002-5865-7924"
},
{
"name": {
"family": "Wang",
"given": "Haimin"
},
"orcid": "0000-0002-5233-565X"
},
{
"name": {
"family": "Yu",
"given": "Sijie"
},
"orcid": "0000-0003-2872-2614"
}
]
},
"title": "Two Phases of Particle Acceleration of a Solar Flare Associated with In Situ Energetic Particles",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar flares; Solar energetic particles; Solar radio emission; Solar x-ray emission",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors thank Säm Krucker, William Setterberg, and Yixian Zhang for valuable discussions on HXR spectral analysis. This work is primarily funded by NASA HSO Connect grants 80NSSC20K1282 and 80NSSC20K1283 to NJIT (through a subcontract from SAO). M.W. and B.C. receive additional support from NSF SHINE grant AGS-2229338 to NJIT. H.W. is also supported by NASA grant 80NSSC24M0174. The Expanded Owens Valley Solar Array (EOVSA) was designed and built and is now operated by the New Jersey Institute of Technology (NJIT) as a community facility. EOVSA operations are supported by NSF grants AGS-2130832 and NASA grant 80NSSC20K0026 to NJIT. The authors are grateful to the PSP/IS\u2299IS, Fermi/GBM, SDO, e-Callisto, WIND, and ACE teams for making their data publicly available.
\n\nOVRO:SA - Owens Valley Radio Observatory's Solar Array, Fermi - Fermi Gamma-Ray Space Telescope (formerly GLAST), Parker - , WIND - NASA's solar WIND satellite, ACE - Advanced Composition Explorer satellite, SDO - Solar Dynamics Observatory, GOES - Geostationary Operational Environmetal Satellite.
",
"abstract": "How impulsive solar energetic particle (SEP) events are produced by magnetic-reconnection-driven processes during solar flares remains an outstanding question. Here we report a short-duration SEP event associated with an X-class eruptive flare on 2021 July 3, using a combination of remote sensing observations and in situ measurements. The in situ SEPs were recorded by multiple spacecraft including the Parker Solar Probe. The hard X-ray (HXR) light curve exhibits two impulsive periods. The first period is characterized by a single peak with a rapid rise and decay, while the second period features a more gradual HXR light curve with a harder spectrum. Such observation is consistent with in situ measurements: the energetic electrons were first released during the early impulsive phase when the eruption was initiated. The more energetic in situ electrons were released several minutes later during the second period of the impulsive phase when the eruption was well underway. This second period of energetic electron acceleration also coincides with the release of in situ energetic protons and the onset of an interplanetary type III radio burst. We conclude that these multimessenger observations favor a two-phase particle acceleration scenario: the first, less energetic electron population was produced during the initial reconnection that triggers the flare eruption, and the second, more energetic electron population was accelerated in the region above the loop-top below a well-developed, large-scale reconnection current sheet induced by the eruption.
",
"date": "2025-04-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "983",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "33",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/gh0bd-sme31",
"funders": {
"items": [
{
"agency": "National Aeronautics and Space Administration",
"grant_number": "80NSSC20K1282"
},
{
"agency": "National Aeronautics and Space Administration",
"grant_number": "80NSSC20K1283"
},
{
"agency": "National Science Foundation",
"grant_number": "AGS-2229338"
},
{
"grant_number": "80NSSC24M0174"
},
{
"agency": "National Science Foundation",
"grant_number": "AGS-2130832"
},
{
"agency": "National Aeronautics and Space Administration",
"grant_number": "80NSSC20K0026"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.3847/1538-4357/adbdd0",
"primary_object": {
"basename": "Wang_2025_ApJ_983_33.pdf",
"url": "https://authors.library.caltech.edu/records/gh0bd-sme31/files/Wang_2025_ApJ_983_33.pdf"
},
"pub_year": "2025",
"author_list": "Wang \u738b, Meiqi \u7f8e\u797a; Chen \u9648, Bin \u5f6c; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4dejb-xz935",
"eprint_status": "archive",
"datestamp": "2025-08-01 20:30:53",
"lastmod": "2026-03-10 00:33:21",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Muro-Gabriel-D",
"name": {
"family": "Muro",
"given": "G. D."
},
"orcid": "0000-0003-0581-1278"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Z."
},
"orcid": "0000-0002-9246-996X"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"name": {
"family": "De Nolfo",
"given": "G."
},
"orcid": "0000-0002-3677-074X"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Fraschetti",
"given": "F."
},
"orcid": "0000-0002-5456-4771"
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Labrador-Allan",
"name": {
"family": "Labrador",
"given": "A."
},
"orcid": "0000-0001-9178-5349"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Rankin",
"given": "J."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Shen",
"given": "M."
},
"orcid": "0000-0002-3093-458X"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Romeo",
"given": "O."
},
"orcid": "0000-0002-4559-2199"
},
{
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
}
]
},
"title": "Radial Dependence of Ion Fluences in the 2023 July 17 Solar Energetic Particle Event from Parker Solar Probe to STEREO and ACE",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar storm; Solar activity; Solar coronal mass ejections",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
\n
We acknowledge the contributions of the Parker Solar Probe, STEREO, and ACE mission teams in collecting and providing data for this study. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA’s Living with a Star program, contract No. NNN06AA01C. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We thank the scientists and engineers whose technical contributions prelaunch have made the IS\u2299IS instruments such a success. A.V. was supported by NASA grant No. 80NSSC22K0970. As always, we thank the Sun for providing the energy and particles necessary for this inquiry.
\n
\n
\n
In the latter moments of 2023 July 17, the solar active region (AR) 13363, near the southwestern face of the Sun, was undergoing considerable evolution, which resulted in a significant solar energetic particle (SEP) event measured by Parker Solar Probe’s Integrated Science Investigation of the Sun (IS\u2299IS) and near-Earth spacecraft. Remote observations from GOES and CHASE captured two M5.0+ solar flares that peaked at 23:34 and 00:06 UT from the source region. In tandem, STEREO COR2 first recorded a small, narrow coronal mass ejection (CME) emerging at 22:54 UT and then saw a major halo CME emerge at 23:43 UT with a bright, rapidly expanding core and CME-driven magnetic shock with an estimated speed of ∼1400 km s−1. Parker Solar Probe was positioned at 0.65 au, near-perfectly on the nominal Parker spiral magnetic field line, which connected Earth and the AR for a 537 km s−1 ambient solar wind speed at L1. This fortuitous alignment provided the opportunity to examine how the SEP velocity dispersion, energy spectra, elemental composition, and fluence varied from 0.65 to 1 au along a shared magnetic connection to the Sun. We find a strong radial gradient, which is best characterized for H and He as r−4.0, and most surprisingly, is stronger for O and Fe, which is better described by r−5.7.
\n
© 2025. American Geophysical Union. All Rights Reserved.
\n\n\n
J.G.A.G. is supported by NASA Grant 80NSSC24K0568. V.A.F. acknowledges support from NASA Grant 80NSSC20K0786 and NSF Grant 2009871. R.A.L. acknowledges support from NASA Grant 80NSSC23K0543. L.Z., X.Z., A.S., and N.S.M.S. acknowledge partial support by NASA awards 80NSSC20K1783 and 80NSSC23K0415. A.S. is partially supported by NASA Grant 80NSSC24K1867. J.G.A.G would like to thank Swati Sharma for her prompt and generous responses to his frequent requests for literature review material.
\n
\n
\n\n\n
We obtained our data for instruments onboard the ACE directly from the ACE Science Center (https://izw1.caltech.edu/ACE/ASC/index.html). For the solar wind bulk quantities, we used 64s Level 2 (Verified) data from the Magnetic Field Experiment (MAG) (C. Smith et al., 1998) and the Solar Wind Electron, Proton, and Alpha Monitor (SWEPAM) (McComas et al., 1998) instruments. For the cosmic rays, we used 1-hr Level 3 (Contributed) data from the CRIS (Stone et al., 1998) instrument. Specifically, at the time of submission of this manuscript, it is the first entry under the category “Cosmic rays, Particle fluences, other Items.” The code used to perform the data analysis (Alonso Guzman, 2025) is freely available on GitHub (https://github.com/jgaloguz/SIR-analysis-tools).
\n\n
\n
In the inner heliosphere, stream interaction regions (SIR), where fast and slow solar wind streams meet, modulate the intensity of galactic cosmic rays (GCR) on the timescale of a few days. We perform a superposed epoch analysis (SEA) of solar wind, magnetic field, and high\u2010energy particle count rate data from the Advanced Composition Explorer to calculate the average bulk and turbulent features of SIRs associated with strong GCR depressions, as well as a mean percentage change profile for the galactic proton flux during these events. In particular, we split the power of nearly incompressible magnetic turbulence throughout the SIR epoch into the common slab and 2D modes, since these contribute to energetic particle diffusion in different directions relative to the background, time\u2010averaged field. We use the SEA results to compute parallel and perpendicular diffusion coefficients for GCRs during the passage of an average SIR and discuss our findings in the context of the particle observations and prior research. Our results suggest that GCR depletions through an SIR are primarily driven by a sharp decrease in the diffusion coefficients.
",
"date": "2025-03",
"date_type": "published",
"publication": "Journal of Geophysical Research: Space Physics",
"volume": "130",
"number": "3",
"publisher": "American Geophysical Union",
"pagerange": "e2024JA033567",
"issn": "2169-9380",
"official_url": "https://authors.library.caltech.edu/records/69xxc-pet54",
"funders": {
"items": [
{
"grant_number": "80NSSC24K0568"
},
{
"grant_number": "80NSSC20K0786"
},
{
"grant_number": "AST-2009871"
},
{
"grant_number": "80NSSC23K0543"
},
{
"grant_number": "80NSSC20K1783"
},
{
"grant_number": "80NSSC23K0415"
},
{
"grant_number": "80NSSC24K1867"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.1029/2024ja033567",
"primary_object": {
"basename": "JGR Space Physics - 2025 - Alonso Guzm\u00e1n - Superposed Epoch Analysis of Stream Interaction Regions at 1 au During Solar.pdf",
"url": "https://authors.library.caltech.edu/records/69xxc-pet54/files/JGR Space Physics - 2025 - Alonso Guzm\u00e1n - Superposed Epoch Analysis of Stream Interaction Regions at 1 au During Solar.pdf"
},
"pub_year": "2025",
"author_list": "Alonso Guzm\u00e1n, J. G.; Ghanbari, K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vb2ea-1f635",
"eprint_status": "archive",
"datestamp": "2025-02-25 19:41:39",
"lastmod": "2026-03-10 03:36:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Cuesta",
"given": "M. E."
},
"orcid": "0000-0002-7341-2992"
},
{
"name": {
"family": "Khoo",
"given": "L. Y."
},
"orcid": "0000-0003-0412-1064"
},
{
"name": {
"family": "Livadiotis",
"given": "G."
},
"orcid": "0000-0002-7655-6019"
},
{
"name": {
"family": "Shen",
"given": "M. M."
},
"orcid": "0000-0002-3093-458X"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Bandyopadhyay",
"given": "R."
},
"orcid": "0000-0002-6962-0959"
},
{
"name": {
"family": "Farooki",
"given": "H. A."
},
"orcid": "0000-0001-7952-8032"
},
{
"name": {
"family": "Niehof",
"given": "J. T."
},
"orcid": "0000-0001-6286-5809"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "Richard A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Z."
},
"orcid": "0000-0002-9246-996X"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Dayeh",
"given": "M. A."
},
"orcid": "0000-0001-9323-1200"
}
]
},
"title": "Comparing Methods for Calculating Solar Energetic Particle Intensities: Rebinning versus Spectral Binning",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar wind; Solar physics",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the IS\u2299IS team and everyone that made the PSP mission possible. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/PSP. PSP was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C).
",
"abstract": "Solar energetic particle (SEP) events have been observed for decades in the interplanetary medium by spacecraft measuring the intensity of energetic ions and electrons. These intensities provide valuable information about particle acceleration, the effects of bulk plasma dynamics on particle transport, and the anisotropy of particle distributions. Since measured intensities are typically reported in narrow energy bins, it is common to rebin intensities over a wider energy range to improve counting statistics. We investigate two methods for calculating intensities across multiple energy bins: (a) rebinned intensity (j\u2015linlin), which is calculated by integrating the intensity over energy space and corresponds to the intensity at an effective energy that depends on the time-varying spectral index, and (b) spectral binned intensity (j\u2015loglog), calculated by integrating the log intensity in log–energy space, yielding the intensity at the log-centered energy that is independent of the spectral index and remains constant over time. We compare these methods using Parker Solar Probe (PSP) IS\u2299IS measurements of energetic protons, and we prescribe criteria for selecting the appropriate method for different scenarios. Our results show that the rebinned intensity is consistently larger (up to a factor of 5) than the spectral binned intensity for two SEP events observed by PSP, although the time series of the two methods are strongly correlated. Overall, both measures are important for SEP spectral analysis, and the selection of the appropriate measure depends on whether a physical (spectral binned intensity) or a statistical (rebinned intensity) representation is needed for a given analysis.
",
"date": "2025-02-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "980",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "235",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/vb2ea-1f635",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4357/adaea9",
"primary_object": {
"basename": "Cuesta_2025_ApJ_980_235.pdf",
"url": "https://authors.library.caltech.edu/records/vb2ea-1f635/files/Cuesta_2025_ApJ_980_235.pdf"
},
"pub_year": "2025",
"author_list": "Cuesta, M. E.; Khoo, L. Y.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5dke3-9br03",
"eprint_status": "archive",
"datestamp": "2025-02-25 22:42:59",
"lastmod": "2025-02-25 22:42:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Hyndman",
"given": "R. A."
},
"orcid": "0009-0009-9563-0446"
},
{
"name": {
"family": "Dalla",
"given": "S."
},
"orcid": "0000-0002-7837-5780"
},
{
"name": {
"family": "Laitinen",
"given": "T."
},
"orcid": "0000-0002-7719-7783"
},
{
"name": {
"family": "Hutchinson",
"given": "A."
},
"orcid": "0000-0002-9362-7165"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Wimmer-Schweingruber",
"given": "R. F."
}
}
]
},
"title": "Multi-spacecraft observations of the decay phase of solar energetic particle events",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: activity; Sun: coronal mass ejections (CMEs); Sun: flares; Sun: heliosphere; Sun: particle emission",
"note": "© The Authors 2025.
\nOpen Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
\n\nR.H. acknowledges funding from the Moses Holden Studentship for her PhD. T.L. and S.D. acknowledge support from the UK Science and Technology Facilities Council (STFC) through grants ST/V000934/1 and ST/Y002725/1. A.H. would like to acknowledge support from the University of Maryland Baltimore County (UMBC), the Partnership for Heliophysics and Space Environment Research (PHaSER), and NASA/GFSC. We acknowledge use of solar energetic particle data from the SOHO, STEREO-A, Solar Orbiter and PSP spacecraft and thank the instrument teams for their work on making the data available and science-ready. Solar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. Thanks to the Integrated Science Investigation of the Sun (IS\u2299IS) Science Team (PI: David McComas, Princeton University), and the Energetic Particle Detector (EPD) Team (PI: Javier Rodríguez-Pacheco, University of Alcalá, Spain). We acknowledge use of SERPENTINE tools, which were developed with funding from the European Union’s Horizon 2020 research and innovation program, and of the Solar-MACH tool. The use of the data made available via the NSSDC CDAWeb is acknowledged.
\n\nAll spacecraft data used in this paper are publicly available and can be retrieved using the EU SERPENTINE software (Palmroos et al. 2022). Details of the events studied are provided in Table 2. Results derived from our data analysis are available in Table A.1.
",
"abstract": "Context. The parameters of solar energetic particle (SEP) event profiles such as the onset time and peak time have been researched extensively to obtain information on the acceleration and transport of SEPs. The corotation of particle-filled magnetic flux tubes with the Sun is generally thought to play a minor role in determining intensity profiles. However recent simulations have suggested that corotation affects the SEP decay phases and depends on the location of the observer with respect to the active region associated with the event.
\nAims. We aim to determine whether signatures of corotation are present in observations of the decay phases of SEP events, and we study the dependence of the parameters of the decay phase on the properties of the flares and coronal mass ejections associated with the events.
\nMethods. We analysed multi-spacecraft observations of SEP intensity profiles from 11 events between 2020 and 2022 using data from Solar Orbiter, PSP, STEREO-A, and SOHO. We determined the decay-time constant, τ, in three energy channels; electrons ∼ 1 MeV, protons ∼ 25 MeV, and protons ∼ 60 MeV. We studied the dependence of τ on the longitudinal separation, Δ\u03d5, between the source of the active region and the spacecraft magnetic footpoint on the Sun.
\nResults. Individual events show a tendency for the decay-time constant to decrease with increasing Δ\u03d5. This agrees with test particle simulations. The magnitude of the event as measured through the intensity of the associated flare and SEP peak flux affects the measured τ values and likely is the cause of the observed large inter-event variability together with the varying solar wind and the conditions in the interplanetary magnetic field.
\nConclusions. We conclude that corotation affects decay phase of an SEP event and should be included in future simulations and interpretations of these events.
",
"date": "2025-02",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "694",
"publisher": "EDP Sciences",
"pagerange": "A242",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/5dke3-9br03",
"funders": {
"items": [
{
"grant_number": "ST/V000934/1"
},
{
"grant_number": "ST/Y002725/1"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202453012",
"primary_object": {
"basename": "aa53012-24.pdf",
"url": "https://authors.library.caltech.edu/records/5dke3-9br03/files/aa53012-24.pdf"
},
"pub_year": "2025",
"author_list": "Hyndman, R. A.; Dalla, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jy1v0-3f651",
"eprint_status": "archive",
"datestamp": "2025-01-23 15:32:53",
"lastmod": "2025-01-23 15:32:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Woo",
"given": "Jooyun"
},
"orcid": "0009-0001-6471-1405"
},
{
"name": {
"family": "Mori",
"given": "Kaya"
},
"orcid": "0000-0002-9709-5389"
},
{
"name": {
"family": "Hailey",
"given": "Charles J."
},
"orcid": "0000-0002-3681-145X"
},
{
"name": {
"family": "Spira-Savett",
"given": "Elizabeth"
},
"orcid": "0009-0009-6387-7241"
},
{
"name": {
"family": "Bamba",
"given": "Aya"
},
"orcid": "0000-0003-0890-4920"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"name": {
"family": "Humensky",
"given": "Thomas B."
},
"orcid": "0000-0002-1432-7771"
},
{
"name": {
"family": "Mukherjee",
"given": "Reshmi"
},
"orcid": "0000-0002-3223-0754"
},
{
"name": {
"family": "Safi-Harb",
"given": "Samar"
},
"orcid": "0000-0001-6189-7665"
},
{
"name": {
"family": "Temim",
"given": "Tea"
},
"orcid": "0000-0001-7380-3144"
},
{
"name": {
"family": "Tsuji",
"given": "Naomi"
},
"orcid": "0000-0001-7209-9204"
}
]
},
"title": "Spectrum and Location of Ongoing Extreme Particle Acceleration in Cassiopeia A",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Supernova remnants; Galactic cosmic rays; X-ray astronomy",
"note": "© 2025. The Author(s). Published by the American Astronomical Society.
\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank T. Sato, D. Caprioli, R. Diesing, and S. Reynolds for the discussions. Support for this work was partially provided by NASA through NuSTAR Cycle 8 Guest Observer (GO) Program grant NNH21ZDA001N. J.W. was partially supported by NSF grant WOU MMA PHY-2110497.
\n\nNuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission.
\n\nNuSTARDAS, Xspec (K. A. Arnaud 1996), NumPy (C. R. Harris et al. 2020), SciPy (P. Virtanen et al. 2020), Astropy (Astropy Collaboration et al. 2013, 2018, 2022), Gammapy (A. Donath et al. 2023; A. Aguasca-Cabot et al. 2023), Matplotlib (J. D. Hunter 2007), Naima (V. Zabalza 2015).
",
"abstract": "\n
Young supernova remnants (SNRs) are believed to be the origin of energetic cosmic rays (CRs) below the \"knee\" of their spectrum at ∼3 PeV (1015 eV). Nevertheless, the precise location, duration, and operation of CR acceleration in young SNRs are open questions. Here, we report on multiepoch X-ray observations of Cassiopeia A (Cas A), a 350 yr old SNR, in the 15–50 keV band that probes the most energetic CR electrons. The observed X-ray flux decrease (15% ± 1% over 10 yr), contrary to the expected >90% decrease based on previous radio, X-ray, and gamma-ray observations, provides unambiguous evidence for CR electron acceleration operating in Cas A. A temporal model for the radio and X-ray data accounting for electron cooling and continuous injection finds that the freshly injected electron spectrum is significantly harder (exponential cutoff power-law index q = 2.15), and its cutoff energy is much higher (Ecut = 36 TeV), than the relic electron spectrum (q = 2.44 ± 0.03, Ecut = 4 ± 1 TeV). Both electron spectra are naturally explained by the recently developed modified nonlinear diffusive shock acceleration (mNLDSA) mechanism. The CR protons producing the observed gamma rays are likely accelerated at the same location by the same mechanism as the injected electrons. The Cas A observations and spectral modeling represent the first time radio, X-ray, gamma-ray, and CR spectra have been self-consistently tied to a specific acceleration mechanism—mNLDSA—in a young SNR.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe IXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). Funding for this work was provided in part by contract 80MSFC17C0012 from the MSFC to MIT in support of the IXPE project. Support for this work was provided in part by the National Aeronautics and Space Administration (NASA) through the Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 to MIT for support of the Chandra X-ray Center (CXC), which is operated by SAO for and on behalf of NASA under contract NAS8-03060. I.L and B.A.-G. were funded by the European Union ERC-2022-STG—BOOTES—101076343. The views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. This research has made use of data from the RoboPol program, a collaboration between Caltech, the University of Crete, IA-FORTH, IUCAA, the MPIfR, and the Nicolaus Copernicus University, which was conducted at Skinakas Observatory in Crete, Greece. The IAA-CSIC coauthors acknowledge financial support from the Spanish “Ministerio de Ciencia e Innovacion” (MCINN) through the “Center of Excellence Severo Ochoa” award for the Instituto de Astrofísica de Andalucía-CSIC (SEV-2017-0709). Acquisition and reduction of the POLAMI, TOP-MAPCAR, and OSN data was supported in part by MICINN through grant Nos. AYA2016-80889-P and PID2019-107847RB-C44. Some of the data are based on observations collected at the Observatorio de Sierra Nevada, owned and operated by the Instituto de Astrofísica de Andalucía (IAA-CSIC). Further data are based on observations collected at the Centro Astronómico Hispano-Alemán (CAHA), operated jointly by Junta de Andalucía and Consejo Superior de Investigaciones Científicas (IAA-CSIC). The POLAMI observations were carried out at the IRAM 30 m Telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain). Some of the data reported here are based on observations obtained at the Hale Telescope, Palomar Observatory as part of a continuing collaboration between the California Institute of Technology, NASA/JPL, Yale University, and the National Astronomical Observatories of China. G.V.P. acknowledges support by NASA through the NASA Hubble Fellowship grant No. HST-HF2-51444.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. The data in this study include observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku and the University of Oslo, representing Denmark, Finland, and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The data presented here were obtained in part with ALFOSC, which is provided by the Instituto de Astrofísica de Andalucía (IAA) under a joint agreement with the University of Copenhagen and NOT. E.L. was supported by Academy of Finland projects 317636 and 320045. D.B., S.K., R.S., and N.M. acknowledge support from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program under grant agreement No. 771282. C.C. acknowledges support by the European Research Council (ERC) under the HORIZON ERC Grants 2021 program under grant agreement No. 101040021. The Dipol-2 polarimeter was built in cooperation by the University of Turku, Finland, and the Leibniz Institut für Sonnenphysik, Germany, with support from the Leibniz Association grant No. SAW-2011-KIS-7. This work was supported by JST, the establishment of university fellowships toward the creation of science technology innovation, grant No. JPMJFS2129. This work was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI grant No. JP21H01137. This work was also partially supported by the Optical and Near-Infrared Astronomy Inter-University Cooperation Program from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. We are grateful to the observation and operating members of Kanata Telescope. The research at Boston University was supported in part by National Science Foundation grant AST-2108622, NASA Fermi Guest Investigator grant No. 80NSSC23K1507, and NASA Swift Guest Investigator grant No. 80NSSC22K0537. This study used observations conducted with the 1.8 m Perkins Telescope Observatory (PTO) in Arizona (USA), which is owned and operated by Boston University. The Submillimeter Array is a joint project between the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics and is funded by the Smithsonian Institution and the Academia Sinica. Maunakea, the location of the SMA, is a culturally important site for the indigenous Hawaiian people; we are privileged to study the cosmos from its summit. The KVN is a facility operated by the Korea Astronomy and Space Science Institute. The KVN operations are supported by Korea Research Environment Open NETwork (KREONET), which is managed and operated by the Korea Institute of Science and Technology Information (KISTI). Partly based on observations with the 100 m telescope of the Max-Planck-Institut für Radioastronomie (MPIfR) at Effelsberg. Observations with the 100 m radio telescope at Effelsberg have received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004719 (ORP). This paper makes use of the following ALMA director’s discretionary time data under proposal ESO#2021.A.00016.T. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ.
\n\nALMA - Atacama Large Millimeter Array, CAO:2.2m, CrAO:0.7m, Effelsberg, IRAM:30m, IXPE, LX-200, Kanata, KVN, NOT, Hale, Perkins, Skinakas:1.3m, SMA, Swift, TU:0.6m (DIPOL-2).
\n\nixpeobssim (Baldini et al. 2022), Astropy (Astropy Collaboration et al. 2013, 2018), Photutils (Bradley et al. 2019), NumPy and SciPy (Virtanen et al. 2020), IPython (Perez & Granger 2007), HEASoft 6.30.1 88 (NASA High Energy Astrophysics Science Archive Research Center 2014), 3ML (Vianello et al. 2015).
",
"abstract": "We present X-ray polarimetry observations from the Imaging X-ray Polarimetry Explorer (IXPE) of three low spectral peak and one intermediate spectral peak blazars, namely 3C 273, 3C 279, 3C 454.3, and S5 0716+714. For none of these objects was IXPE able to detect X-ray polarization at the 3σ level. However, we placed upper limits on the polarization degree at ∼10%–30%. The undetected polarizations favor models where the X-ray band is dominated by unpolarized photons upscattered by relativistic electrons in the jets of blazars, although hadronic models are not completely eliminated. We discuss the X-ray polarization upper limits in the context of our contemporaneous multiwavelength polarization campaigns.
",
"date": "2024-09-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "972",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "74",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/7skrd-ajz35",
"funders": {
"items": [
{
"grant_number": "NNM15AA18C"
},
{
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"grant_number": "SV3-73016"
},
{
"grant_number": "NAS8-03060"
},
{
"grant_number": "101076343"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n",
"grant_number": "SEV-2017-0709"
},
{
"grant_number": "AYA2016-80889-P"
},
{
"grant_number": "PID2019-107847RB-C44"
},
{
"grant_number": "HST-HF2-51444.001-A"
},
{
"grant_number": "NAS5-26555"
},
{
"grant_number": "317636"
},
{
"grant_number": "320045"
},
{
"grant_number": "771282"
},
{
"grant_number": "101040021"
},
{
"grant_number": "JPMJFS2129"
},
{
"grant_number": "JP21H01137"
},
{
"grant_number": "AST-2108622"
},
{
"grant_number": "80NSSC23K1507"
},
{
"grant_number": "80NSSC22K0537"
},
{
"grant_number": "101004719"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "TAPIR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4357/ad5671",
"primary_object": {
"basename": "Marshall_2024_ApJ_972_74.pdf",
"url": "https://authors.library.caltech.edu/records/7skrd-ajz35/files/Marshall_2024_ApJ_972_74.pdf"
},
"pub_year": "2024",
"author_list": "Marshall, Herman L.; Liodakis, Ioannis; et al."
},
{
"id": "https://authors.library.caltech.edu/records/wchce-m0146",
"eprint_status": "archive",
"datestamp": "2024-06-20 20:23:36",
"lastmod": "2026-02-03 21:50:57",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Heyl-Jeremy-S",
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Gonz\u00e1lez-Caniulef",
"given": "Denis"
},
"orcid": "0000-0001-5848-0180"
},
{
"id": "Caiazzo-Ilaria",
"name": {
"family": "Caiazzo",
"given": "Ilaria"
},
"orcid": "0000-0002-4770-5388"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Mushtukov",
"given": "Alexander"
},
"orcid": "0000-0003-2306-419X"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Kirmizibayrak",
"given": "Demet"
},
"orcid": "0000-0003-2675-740X"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Forsblom",
"given": "Sofia V."
},
"orcid": "0000-0001-9167-2790"
},
{
"name": {
"family": "Malacaria",
"given": "Christian"
},
"orcid": "0000-0002-0380-0041"
},
{
"name": {
"family": "Suleimanov",
"given": "Valery F."
},
"orcid": "0000-0003-3733-7267"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio Angelo"
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garcia",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Peirson",
"given": "Abel Lawrence"
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Complex rotational dynamics of the neutron star in Hercules X-1 revealed by X-ray polarization",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astrophysical disks; Astrophysical magnetic fields; Compact astrophysical objects; High-energy astrophysics; Quantum fluids and solids",
"note": "© The Author(s), under exclusive licence to Springer Nature Limited 2024.
\n\n\n
\n
IXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center, with industry partner Ball Aerospace (Contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Contract ASI-ASI-OHBI-2022-13-I.0 and Agreements ASI-INAF-2022-19-HH.0 and ASI-INFN-2017.13-H0) and its Space Science Data Center (Agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0), and by the Italian National Institute for Astrophysics and the Italian National Institute for Nuclear Physics. This research used data products provided by the IXPE Team (Marshall Space Flight Center, Space Science Data Center, Italian National Institute for Astrophysics and Italian National Institute for Nuclear Physics) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center at NASA’s Goddard Space Flight Center. J.H. acknowledges support from the Natural Sciences and Engineering Research Council of Canada through a discovery grant, the Canadian Space Agency through the co-investigator grant program, and computational resources and services provided by Compute Canada, Advanced Research Computing at the University of British Columbia, and the SciServer science platform (www.sciserver.org). D.G.-C. acknowledges support from a fellowship grant from the French National Centre for Space Studies. J.P. and S.S.T. were supported by the Academy of Finland (Grant Nos. 333112 and 349144) and the Väisälä Foundation. V.D. and V.F.S. thank the German Academic Exchange Service (Travel Grant No. 57525212). We used Astropy (http://www.astropy.org), a community-developed core Python package and an ecosystem of tools and resources for astronomy.
\n
\n
J.H. analysed the data and wrote the draft of the paper. J.P. led the work of the IXPE Topical Working Group on Accreting Neutron Stars and contributed to the interpretation and the text. V.D., D.G.-C., I.C., A. Mushtukov., S.S.T., D.M. and V.F.S. contributed to the interpretation of the results and writing of the text. A. Mushtukov created Fig. 3. M.B. and G.G.P. acted as internal referees of the paper and contributed to its interpretation. Other members of the IXPE collaboration contributed to the design of the mission and its science case and the planning of the observations. All authors provided input and comments on the paper.
\n\n\n
\n
The data used for this analysis are available through High-Energy Astrophysics Science Archive Research Center under IXPE Observation IDs 01001899, 02003801 and 02004001.
\n
\n
\n
\n
The authors declare that they have no competing financial interests.
\n
\n
\n
\n
In an accreting X-ray pulsar, a neutron star accretes matter from a companion star through an accretion disk. The magnetic field of the rotating neutron star disrupts the inner edge of the disk, funnelling the gas to flow onto the poles on its surface. Hercules X-1 is a prototypical persistent X-ray pulsar about 7 kpc from Earth. Its emission varies on three distinct timescales: the neutron star rotates every 1.2 s, it is eclipsed by its companion each 1.7 d, and the system exhibits a superorbital period of 35 d, which has remained stable since its discovery. Several lines of evidence point to the source of this variation as the precession of the accretion disk or that of the neutron star. Despite the many hints over the past 50 yr, the precession of the neutron star itself has yet not been confirmed or refuted. X-ray polarization measurements (probing the spin geometry of Her X-1) with the Imaging X-ray Polarimetry Explorer suggest that free precession of the neutron star crust sets the 35 d period; this has the important implication that its crust is somewhat asymmetric by a few parts per ten million.
\n
\n
© The Author(s), under exclusive licence to Springer Nature Limited 2024.
\n\n\n
\n
IXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center, with industry partner Ball Aerospace (Contract NNM15AA18C). The Italian contribution is supported by ASI (Contract ASI-OHBI-2017-12-I.0 and Agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0) and its Space Science Data Center and by the Italian National Institute for Astrophysics and the Italian National Institute for Nuclear Physics. For the AMI observations, we thank the staff of the Mullard Radio Astronomy Observatory, University of Cambridge, for their support in the maintenance and operation of the telescope, and we acknowledge support from the European Research Council (Grant No. ERC-2012-StG-307215 LODESTONE). The SMA is a joint project between the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics and is funded by the Smithsonian Institution and the Academia Sinica. SMA is on Maunakea, which is a culturally important site for the indigenous Hawaiian people; we are privileged to study the cosmos from its summit. This work is partly based on observations with the 100-m telescope of the Max Planck Institute for Radio Astronomy at Effelsberg. The research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 101004719; ORP). The AGILE Mission is funded by ASI with scientific and programmatic participation by the Italian National Institute for Astrophysics and the Italian National Institute for Nuclear Physics. This investigation was supported by the ASI (Grant No. I/028/12/7-2022). We thank H. Feng for providing the data on the representative ULX models. F. Muleri, A.D.M., F.L.M., E. Costa, P. Soffitta, S.F. and R.F. are partially supported by the Italian Ministry of Foreign Affairs (Grant No. CN24GR08, GRBAXP: Guangxi-Rome Bilateral Agreement for X-ray Polarimetry in Astrophysics). A.V., J. Poutanen and S.S.T. acknowledge support from the Academy of Finland (Grant Nos. 333112, 347003, 349144, 349373, 349906 and 355672). A.A.M. is supported by the Stephen Hawking fellowship from UK Research and Innovation. H.K. and N.R.C. acknowledge NASA support (Grant Nos. 80NSSC18K0264, 80NSSC22K1291, 80NSSC21K1817 and NNX16AC42G). V.D. thanks the German Academic Exchange Service (Travel Grant No. 57525212). A.I. acknowledges support from the Royal Society. J. Podgorný, M.D., J.S. and V.K. give thanks for support from the Czech Science Foundation (Project 21-06825X) and institutional support from the Astronomical Institute of the Czech Academy of Sciences (Project RVO:67985815). We thank the staff of the GMRT who made these observations possible. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. R.K. acknowledges the support of the Department of Atomic Energy, Government of India (Project No. 12-R&D-TFR-5.02-0700). M.M. is supported by NASA (Contract NAS8-03060). S.A.T. is supported by the Ministry of Science and Higher Education of the Russian Federation (Grant No. 075-15-2022-262; 13.MNPMU.21.0003). A.A.Z. acknowledges support from the Polish National Science Center (Grant No. 2019/35/B/ST9/03944).
\n
\n
A.V. led the modelling of the data and the writing of the paper. F. Muleri led the analysis of the IXPE data. J. Poutanen led the analytical modelling and contributed to the writing of the paper. J. Podgorný performed the Monte Carlo simulations in support of the modelling. M.D. led the work of the IXPE Topical Working Group on Accreting Stellar-mass Black Holes. A.D.R., E. Churazov, P.K. and R.A.S. contributed with parts of the paper and its content. F.C., A.D.M., S.V.F., H.K., F.L.M., A.A.L., S.V.M., A.R., N.R.C., J.F.S., S.S.T., A.A.Z. and J.J.E.K., I.A.M., G.P. and C.P. contributed to planning, reducing and analysing the X-ray and γ-ray data. V.L., A.A.M. and D.M. contributed to analytical estimates and modelling. J.S.B., N. Bursov, E.E., D.A.G., M.G., R.K., A.K., M.M., N.N., M. Pilia, R.R., S.R., A.S., J.S., S.A.T. and P.T. contributed with radio and submillimetre data. S.B., E. Costa, J.A.G., A.I., F. Marin, G.M., P. Soffitta, F. Tombesi, F.U., M.C.W. and K.W. contributed with discussions of the methods and conclusions. The remaining authors contributed to the design, science case of the IXPE mission and the planning of observations relevant to the present paper.
\n\n\n\n\n\n\n\n\n\n\n\nThe authors declare no competing interests.
",
"abstract": "\n
\n
The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds a critical value known as the Eddington limit. The discovery of ultraluminous X-ray sources has shown that accretion can proceed even when the apparent luminosity considerably exceeds this limit. A high apparent luminosity might be produced due to the geometric beaming of radiation by an outflow. The outflow half-opening angle, which determines the amplification due to beaming, has never been robustly constrained. Using the Imaging X-ray Polarimetry Explorer, we measured the X-ray polarization in the Galactic X-ray binary Cygnus X-3 (Cyg X-3). We found high, >20%, nearly energy-independent linear polarization orthogonal to the direction of the radio ejections. These properties unambiguously indicate the presence of a collimating outflow from the X-ray binary Cyg X-3 and constrain its half-opening angle to \u227215°. Thus, the source can be used as a laboratory for studying the supercritical accretion regime. This finding underscores the importance of X-ray polarimetry in advancing our understanding of accreting sources.
\n
\n
© The Authors 2024. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication.
\n\nThe authors acknowledge support from the National Agency for Research and Development (ANID) grants: Millennium Science Initiative Program ICN12_12009 (PSS, LHG, FEB, FF, MPH, AMMA), Millenium Nucleus NCN19_058 (SB, PA, PL, MLMA), CATA-BASAL – FB210003 (FEB, CR, RJA), BASAL FB210005 (AMMA), FONDECYT Regular – 1241005 (FEB), 1230345 (CR), 1201748 (PL), 1200710 (FF), 1231718 (RJA). S.B. acknowledges financial support from ANID Becas 21212344, and the hospitality of ESO under the SSDF Project 28/23D. A.B. acknowledges financial support from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC 2094 – 39078331. D.H. acknowledges support from DLR grant FKZ 50 OR 2003. M.K. acknowledges support from DLR grant FKZ 50 OR 2307. D.T. acknowledges support by DLR grant FKZ 50 OR 2203. A.M. acknowledges support by DLR under the grant 50 QR 2110 (XMM_NuTra). P.A. and S.B. acknowledge support from the Max-Planck Society through a Partner Group grant. M.J.A. acknowledges support from the NSF Grant #2108402. This work has been possible thanks to the use of AWS-U.Chile-NLHPC credits. Powered@NLHPC: This research was partially supported by the supercomputing infrastructure of the NLHPC (ECM-02). Based on observations obtained with the Samuel Oschin 48-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington, Deutsches Elektronen-Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. Based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grants No. AST-1440341 and AST-2034437 and a collaboration including current partners Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, IN2P3, University of Warwick, Ruhr University Bochum, Northwestern University and former partners the University of Washington, Los Alamos National Laboratories, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. We acknowledge the use of public data from the Swift data archive (Obs IDs 00014350003, 00014350004, 00014350005, 00014350007). The scientific results reported in this article are based in part on observations made by the Chandra X-ray Observatory, observation ID: 29355. Based on observations collected at the European Southern Observatory under ESO programme 109.24F5.001. Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia e Inovações (MCTI/LNA) do Brasil, the US National Science Foundation’s NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU), through CNTAC proposal CN2021A-17. Some of he data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the US Department of Energy Office of Science. The SDSS-III website is https://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. Based in part on observations obtained through the Astronomical Event Observatory Network (AEON), a joint endeavor of the Las Cumbres Observatory and of NSF NOIRLab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the U.S. National Science Foundation.
\n\nThe SOAR/Goodman and Keck/LRIS spectra are available at the CDS via anonymous ftp to https://cdsarc.cds.unistra.fr (130.79.128.5) or via https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/688/A157
\n\n\n
\n
Based on observations collected at the European Southern Observatory under ESO programme 109.24F5.001.
\n
\n
Context. The early-type galaxy SDSS J133519.91+072807.4 (hereafter SDSS1335+0728), which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Facility (ZTF) alert stream from December 2019 (as ZTF19acnskyy). This variability behaviour, coupled with the host-galaxy properties, suggests that SDSS1335+0728 hosts a ∼106\u2006M\u2299 black hole (BH) that is currently in the process of “turning on”.
\nAims. We present a multi-wavelength photometric analysis and spectroscopic follow-up performed with the aim of better understanding the origin of the nuclear variations detected in SDSS1335+0728.
\nMethods. We used archival photometry (from WISE, 2MASS, SDSS, GALEX, eROSITA) and spectroscopic data (from SDSS and LAMOST) to study the state of SDSS1335+0728 prior to December 2019, and new observations from Swift, SOAR/Goodman, VLT/X-shooter, and Keck/LRIS taken after its turn-on to characterise its current state. We analysed the variability of SDSS1335+0728 in the X-ray/UV/optical/mid-infrared range, modelled its spectral energy distribution prior to and after December 2019, and studied the evolution of its UV/optical spectra.
\nResults. From our multi-wavelength photometric analysis, we find that: (a) since 2021, the UV flux (from Swift/UVOT observations) is four times brighter than the flux reported by GALEX in 2004; (b) since June 2022, the mid-infrared flux has risen more than two times, and the W1\u2005−\u2005W2 WISE colour has become redder; and (c) since February 2024, the source has begun showing X-ray emission. From our spectroscopic follow-up, we see that (i) the narrow emission line ratios are now consistent with a more energetic ionising continuum; (ii) broad emission lines are not detected; and (iii) the [OIII] line increased its flux ∼3.6 years after the first ZTF alert, which implies a relatively compact narrow-line-emitting region.
\nConclusions. We conclude that the variations observed in SDSS1335+0728 could be either explained by a ∼106\u2006M\u2299 AGN that is just turning on or by an exotic tidal disruption event (TDE). If the former is true, SDSS1335+0728 is one of the strongest cases of an AGN observed in the process of activating. If the latter were found to be the case, it would correspond to the longest and faintest TDE ever observed (or another class of still unknown nuclear transient). Future observations of SDSS1335+0728 are crucial to further understand its behaviour.
",
"date": "2024-08",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "688",
"publisher": "EDP Sciences",
"pagerange": "A157",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/0xd01-3zz12",
"funders": {
"items": [
{
"grant_number": "ICN12_12009"
},
{
"grant_number": "NCN19_058"
},
{
"grant_number": "CATA-BASAL - FB210003"
},
{
"grant_number": "BASAL FB210005"
},
{
"grant_number": "1241005"
},
{
"grant_number": "1230345"
},
{
"grant_number": "1201748"
},
{
"grant_number": "1200710"
},
{
"grant_number": "1231718"
},
{
"grant_number": "21212344"
},
{
"grant_number": "SSDF Project 28/23D"
},
{
"grant_number": "EXC 2094 \u2013 39078331"
},
{
"grant_number": "FKZ 50 OR 2003"
},
{
"grant_number": "FKZ 50 OR 2307"
},
{
"grant_number": "50 QR 2110"
},
{},
{
"grant_number": "AST-2108402"
},
{
"grant_number": "AST-1440341"
},
{},
{},
{},
{}
]
},
"local_group": {
"items": [
{
"id": "Zwicky-Transient-Facility"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202347957",
"primary_object": {
"basename": "aa47957-23.pdf",
"url": "https://authors.library.caltech.edu/records/0xd01-3zz12/files/aa47957-23.pdf"
},
"pub_year": "2024",
"author_list": "S\u00e1nchez-S\u00e1ez, P.; Hernandez-Garcia, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7cspr-k7h76",
"eprint_status": "archive",
"datestamp": "2024-07-16 19:19:16",
"lastmod": "2026-03-10 00:33:15",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "Alan C."
},
"orcid": "0000-0002-3840-7696"
}
]
},
"title": "Edward C. Stone obituary: physicist who guided Voyager probes to interstellar space",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2024 Springer Nature Limited.
\n\n\n
The author declares no competing interests.
\n
Edward Stone was a pre-eminent space scientist with an exceptional record of leading space missions and building ground-based astronomical facilities. The public face of NASA’s Voyager missions for the launch of the two probes in 1977, he served as project scientist for 50 years. Stone introduced the world to the wonders of the gas-giant planets (Jupiter, Saturn, Uranus and Neptune) in multiple press conferences, from Voyager 1’s encounter with Jupiter in 1979 to Voyager 2’s fly-by of Neptune in 1989. He also oversaw the probes entering interstellar space — the first in 2012 and the second in 2018. They continue to transmit data to Earth today.
",
"date": "2024-07-18",
"date_type": "published",
"publication": "Nature",
"volume": "631",
"number": "8021",
"publisher": "Nature Publishing Group",
"pagerange": "501",
"issn": "0028-0836",
"official_url": "https://authors.library.caltech.edu/records/7cspr-k7h76",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.1038/d41586-024-02285-w",
"pub_year": "2024",
"author_list": "Cummings, Alan C."
},
{
"id": "https://authors.library.caltech.edu/records/ae52r-5qy37",
"eprint_status": "archive",
"datestamp": "2024-07-05 23:54:19",
"lastmod": "2024-07-05 23:54:19",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Sarlis-Nicholas-V",
"name": {
"family": "Sarlis",
"given": "N. V."
},
"orcid": "0000-0002-8483-519X"
},
{
"id": "Livadiotis-George",
"name": {
"family": "Livadiotis",
"given": "G."
},
"orcid": "0000-0002-7655-6019"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Cuesta-Manuel-E",
"name": {
"family": "Cuesta",
"given": "M. E."
},
"orcid": "0000-0002-7341-2992"
},
{
"id": "Khoo-Leng-Ying",
"name": {
"family": "Khoo",
"given": "L. Y."
},
"orcid": "0000-0003-0412-1064"
},
{
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
}
]
},
"title": "Persistent Behavior in Solar Energetic Particle Time Series",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe acknowledge support through PSP/IS\u2299IS funding (PSP/ISOIS – Integrated Science Investigation of the Sun AWD 1004920 NASA#136435). PSP is a part of NASA's Living with a Star (LWS) program (contract NNN06AA01C).
\n\ndfa.c (Peng et al. 1994, 1995; Goldberger et al. 2000), TISEAN package (Hegger et al. 1999; Kantz & Schreiber 2004), R: A Language and Environment for Statistical Computing (R Core Team 2013), psych (William 2024)
",
"abstract": "\n
We investigate the long-term persistence of solar energetic particle (SEP) time series by means of four different methods: Hurst rescaled range R/S analysis, detrended fluctuation analysis, centered moving average analysis, and the fluctuation of natural time under the time reversal method. For these analyses, we use data sets from the Integrated Science Investigation of the Sun instrument suite on board NASA's Parker Solar Probe. Background systematic noise is modeled using cross-correlation analysis between different SEP energy channels and subtracted from the original data. The use of these four methods for deriving the time-series persistence allows us to (i) differentiate between quiet- and active-Sun periods based on the values of the corresponding self-similarity exponents alone; (ii) identify the onset of an ongoing activity well before it reaches its maximum SEP flux; (iii) reveal an interesting fine structure when activity is observed; and (iv) provide, for the first time, an estimate of the maximum SEP flux of a future storm based on the entropy change of natural time under time reversal.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
This research has made use of MAXI data provided by RIKEN, JAXA, and the MAXI team (Matsuoka et al. 2009). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).
\n
We present two simultaneous NICER and NuSTAR observations of the ultracompact X-ray binary (UCXB) candidate SLX 1735−269 while the source was in two different spectral states. Using various reflection modeling techniques, we find that xillverCO, a model used for fitting X-ray spectra of UCXBs with high carbon and oxygen abundances is an improvement over relxill or relxillNS, which instead contains solar-like chemical abundances. This provides indirect evidence in support of the source being ultracompact. We also use this reflection model to get a preliminary measurement of the inclination of the system, \ud835\udc56=57\u208b\u2087\u207a²³ degrees. This is consistent with our timing analysis, where a lack of eclipses indicates an inclination of i < 80°. The timing analysis is otherwise inconclusive, and we cannot confidently measure the orbital period of the system.
",
"date": "2024-06-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "968",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "51",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/8rmpn-t8z76",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ad4a78",
"primary_object": {
"basename": "Moutard_2024_ApJ_968_51.pdf",
"url": "https://authors.library.caltech.edu/records/8rmpn-t8z76/files/Moutard_2024_ApJ_968_51.pdf"
},
"pub_year": "2024",
"author_list": "Moutard, D. L.; Ludlam, R. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/88y42-wcd73",
"eprint_status": "archive",
"datestamp": "2024-06-25 18:38:15",
"lastmod": "2026-03-10 00:34:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Middleton-Matthew",
"name": {
"family": "Middleton",
"given": "Matthew"
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Ludlam-Renee",
"name": {
"family": "Ludlam",
"given": "Renee"
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Return to the Forgotten Ultraluminous X-Ray Source: A Broadband NICER+NuSTAR Study of NGC 4190 ULX-1",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the anonymous referee for useful comments that improved the clarity of this article. H.P.E. acknowledges support under NASA grant 80NSSC21K0123 and NASA contract NNG08FD60C. The majority of this work was performed on the traditional homeland of the Tongva people.
\nThis work made use of data from the NuSTAR and NICER missions, funded by the National Aeronautics and Space Administration. We thank the observing teams for carrying out the coordinated observations. This work has also made use of archival observations by XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, and the Neil Gehrels Swift Observatory, a NASA science mission.
\n\nNICER - , NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, XMM - Newton X-Ray Multimirror Mission satellite, CXO - Chandra X-ray Observatory satellite, HEASARC - , Swift (XRT) -
\n\nastropy (Astropy Collaboration et al. 2013, 2018), HENDRICS (Bachetti 2018), HEASoft (Nasa High Energy Astrophysics Science Archive Research Center (Heasarc), 2014), NICER software, NuSTARDAS, XMM-Newton SAS, Stingray (Bachetti et al. 2022)
",
"abstract": "\n
We observed the nearby and relatively understudied ultraluminous X-ray source (ULX) NGC 4190 ULX-1 jointly with Neutron Star Interior Composition Explorer (NICER) and NuSTAR to investigate its broadband spectrum, timing properties, and spectral variation over time. We found NGC 4190 ULX-1 to have a hard spectrum characterized by two thermal components (with temperatures ∼0.25 and ∼1.6 keV) and a high-energy excess typical of the ULX population although the spectrum turns over at an unusually low energy. While no pulsations were detected (with pulsed fraction 3σ upper limits of 16% for NICER and 35% for NuSTAR), the source shows significant stochastic variability, and the covariance spectrum indicates the presence of a high-energy cutoff power-law component, potentially indicative of an accretion column. Additionally, when fitting archival XMM-Newton data with a similar model, we find that the luminosity–temperature evolution of the hot thermal component follows the behavior of a super-Eddington slim disk though the expected spectral broadening for such a disk is not seen, suggesting that the inner accretion disk may be truncated by a magnetic field. Therefore, despite the lack of detected pulsations, there is tantalizing evidence for NGC 4190 ULX-1 being a candidate neutron star accretor although further broadband observations will be required to confirm this behavior.
\n
© The Authors 2024. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication.
\n\nThe authors acknowledge support from the National Agency for Research and Development (ANID) grants: Millennium Science Initiative Program ICN12_12009 (PSS,LHG,FEB,FF,MPH,AMMA), Millenium Nucleus NCN19_058 (SB,PA,PL,MLMA), CATA-BASAL - FB210003 (FEB,CR,RJA), BASAL FB210005 (AMMA), FONDECYT Regular - 1241005 (FEB), 1230345 (CR), 1201748 (PL), 1200710 (FF), 1231718 (RJA). SB acknowledges financial support from ANID Becas 21212344, and the hospitality of ESO under the SSDF Project 28/23D. AB acknowledges financial support from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC 2094 – 39078331. DH acknowledges support from DLR grant FKZ 50 OR 2003. MK acknowledges support from DLR grant FKZ 50 OR 2307. DT acknowledges support by DLR grant FKZ 50 OR 2203. AM acknowledges support by DLR under the grant 50 QR 2110 (XMM_NuTra). PA and SB acknowledge support from the Max-Planck Society through a Partner Group grant. MJA acknowledges support from the NSF Grant #2108402. This work has been possible thanks to the use of AWSU. Chile-NLHPC credits. Powered@NLHPC: This research was partially supported by the supercomputing infrastructure of the NLHPC (ECM-02). Based on observations obtained with the Samuel Oschin 48-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington, Deutsches Elektronen-Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. Based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grants No. AST-1440341 and AST-2034437 and a collaboration including current partners Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, IN2P3, University of Warwick, Ruhr University Bochum, Northwestern University and former partners the University of Washington, Los Alamos National Laboratories, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. We acknowledge the use of public data from the Swift data archive (Obs IDs 00014350003, 00014350004, 00014350005, 00014350007). The scientific results reported in this article are based in part on observations made by the Chandra X-ray Observatory, observation ID: 29355. Based on observations collected at the European Southern Observatory under ESO programme 109.24F5.001. Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Minist.rio da Ci.ncia, Tecnologia e Inova..es (MCTI/LNA) do Brasil, the US National Science Foundation’s NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU), through CNTAC proposal CN2021A-17. Some of he data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III web site is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University.
",
"abstract": "Context. The early-type galaxy SDSS J133519.91+072807.4 (hereafter SDSS1335+0728), which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Facility (ZTF) alert stream from December 2019 (as ZTF19acnskyy). This variability behaviour, coupled with the host-galaxy properties, suggests that SDSS1335+0728 hosts a ~10\u2076 M\u2299 black hole (BH) that is currently in the process of ‘turning on’.
\nAims. We present a multi-wavelength photometric analysis and spectroscopic follow-up performed with the aim of better understanding the origin of the nuclear variations detected in SDSS1335+0728.
\nMethods. We used archival photometry (from WISE, 2MASS, SDSS, GALEX, eROSITA) and spectroscopic data (from SDSS and LAMOST) to study the state of SDSS1335+0728 prior to December 2019, and new observations from Swift, SOAR/Goodman, VLT/X-shooter, and Keck/LRIS taken after its turn-on to characterise its current state. We analysed the variability of SDSS1335+0728 in the X-ray/UV/optical/mid-infrared range, modelled its spectral energy distribution prior to and after December 2019, and studied the evolution of its UV/optical spectra.
\nResults. From our multi-wavelength photometric analysis, we find that: (a) since 2021, the UV flux (from Swift/UVOT observations) is four times brighter than the flux reported by GALEX in 2004; (b) since June 2022, the mid-infrared flux has risen more than two times, and the W1−W2 WISE colour has become redder; and (c) since February 2024, the source has begun showing X-ray emission. From our spectroscopic follow-up, we see that (i) the narrow emission line ratios are now consistent with a more energetic ionising continuum; (ii) broad emission lines are not detected; and (iii) the [OIII] line increased its flux ∼ 3.6 years after the first ZTF alert, which implies a relatively compact narrow-line-emitting region.
\nConclusions. We conclude that the variations observed in SDSS1335+0728 could be either explained by a ~10\u2076 M\u2299 AGN that is just turning on or by an exotic tidal disruption event (TDE). If the former is true, SDSS1335+0728 is one of the strongest cases of an AGN observed in the process of activating. If the latter were found to be the case, it would correspond to the longest and faintest TDE ever observed (or another class of still unknown nuclear transient). Future observations of SDSS1335+0728 are crucial to further understand its behaviour.
",
"date": "2024-06-18",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"publisher": "EDP Sciences",
"issn": "0004-6361",
"official_url": "https://authors.library.caltech.edu/records/yc2py-g5v20",
"funders": {
"items": [
{
"grant_number": "ICN12_12009"
},
{
"grant_number": "NCN19_058"
},
{
"grant_number": "CATA-BASAL - FB210003"
},
{
"grant_number": "BASAL FB210005"
},
{
"grant_number": "1241005"
},
{
"grant_number": "1230345"
},
{
"grant_number": "1201748"
},
{
"grant_number": "1200710"
},
{
"grant_number": "1231718"
},
{
"grant_number": "21212344"
},
{
"grant_number": "SSDF Project 28/23D"
},
{
"grant_number": "EXC 2094 \u2013 39078331"
},
{
"grant_number": "FKZ 50 OR 2003"
},
{
"grant_number": "FKZ 50 OR 2307"
},
{
"grant_number": "FKZ 50 OR 2203"
},
{
"grant_number": "50 QR 2110"
},
{},
{
"grant_number": "AST-2108402"
},
{
"grant_number": "AST-1440341"
},
{},
{},
{},
{}
]
},
"local_group": {
"items": [
{
"id": "Zwicky-Transient-Facility"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202347957",
"primary_object": {
"basename": "aa47957-23.pdf",
"url": "https://authors.library.caltech.edu/records/yc2py-g5v20/files/aa47957-23.pdf"
},
"pub_year": "2024",
"author_list": "S\u00e1nchez-S\u00e1ez, P.; Hernandez-Garcia, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ykwe9-8b555",
"eprint_status": "archive",
"datestamp": "2024-06-12 19:11:51",
"lastmod": "2024-06-12 19:11:51",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jebaraj-Immanuel-Christopher",
"name": {
"family": "Jebaraj",
"given": "Immanuel Christopher"
},
"orcid": "0000-0002-0606-7172"
},
{
"id": "Agapitov-Oleksiy",
"name": {
"family": "Agapitov",
"given": "Oleksiy"
},
"orcid": "0000-0001-6427-1596"
},
{
"id": "Krasnoselskikh-Vladimir",
"name": {
"family": "Krasnoselskikh",
"given": "Vladimir"
},
"orcid": "0000-0002-6809-6219"
},
{
"id": "Vuorinen-Laura",
"name": {
"family": "Vuorinen",
"given": "Laura"
},
"orcid": "0000-0002-2238-109X"
},
{
"id": "Gedalin-Michael",
"name": {
"family": "Gedalin",
"given": "Michael"
},
"orcid": "0000-0003-1236-4787"
},
{
"id": "Choi-Kyung-Eun",
"name": {
"family": "Choi",
"given": "Kyung-Eun"
},
"orcid": "0000-0003-2054-6011"
},
{
"id": "Palmerio-Erika",
"name": {
"family": "Palmerio",
"given": "Erika"
},
"orcid": "0000-0001-6590-3479"
},
{
"id": "Wijsen-Nicolas",
"name": {
"family": "Wijsen",
"given": "Nicolas"
},
"orcid": "0000-0001-6344-6956"
},
{
"id": "Dresing-Nina",
"name": {
"family": "Dresing",
"given": "Nina"
},
"orcid": "0000-0003-3903-4649"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina"
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Kouloumvakos-Athanasios",
"name": {
"family": "Kouloumvakos",
"given": "Athanasios"
},
"orcid": "0000-0001-6589-4509"
},
{
"id": "Balikhin-Michael",
"name": {
"family": "Balikhin",
"given": "Michael"
},
"orcid": "0000-0002-8110-5626"
},
{
"id": "Vainio-Rami",
"name": {
"family": "Vainio",
"given": "Rami"
},
"orcid": "0000-0002-3298-2067"
},
{
"id": "Kilpua-Emilia",
"name": {
"family": "Kilpua",
"given": "Emilia"
},
"orcid": "0000-0002-4489-8073"
},
{
"id": "Afanasiev-Alexandr",
"name": {
"family": "Afanasiev",
"given": "Alexandr"
},
"orcid": "0000-0001-9325-6758"
},
{
"id": "Verniero-Jaye",
"name": {
"family": "Verniero",
"given": "Jaye"
},
"orcid": "0000-0003-1138-652X"
},
{
"id": "Mitchell-John-Grant",
"name": {
"family": "Mitchell",
"given": "John Grant"
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Trotta-Domenico",
"name": {
"family": "Trotta",
"given": "Domenico"
},
"orcid": "0000-0002-0608-8897"
},
{
"id": "Hill-Matthew",
"name": {
"family": "Hill",
"given": "Matthew"
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Raouafi-Nour",
"name": {
"family": "Raouafi",
"given": "Nour"
},
"orcid": "0000-0003-2409-3742"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "Stuart D."
},
"orcid": "0000-0002-1989-3596"
}
]
},
"title": "Acceleration of Electrons and Ions by an \"Almost\" Astrophysical Shock in the Heliosphere",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe Parker Solar Probe spacecraft was designed and built and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. The authors express their gratitude to all the instrument teams for their work in processing and publishing the publicly available data from the Parker Solar Probe. All the data used in this study are from the Parker Solar Probe spacecraft. The data used in this study are available at the NASA Space Physics Data Facility (SPDF), https://spdf.gsfc.nasa.gov. This research was supported by the International Space Science Institute (ISSI) in Bern through ISSI International Team project No. 575, \"Collisionless Shock as a Self-Regulatory System.\" I.C.J., N.D., and L.V. are grateful for support by the Academy of Finland (SHOCKSEE, grant No. 346902) and the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004159 (SERPENTINE). O.V.A. was partially supported by NSF grant No. 1914670, NASA's Living with a Star (LWS) program (contract 80NSSC20K0218), and NASA grant contracts 80NNSC19K0848, 80NSSC22K0433, and 80NSSC22K0522. O.V.A. and V.V.K. were supported by NASA grants 80NSSC20K0697 and 80NSSC21K1770. V.V.K. also acknowledges financial support from CNES through grants \"Parker Solar Probe\" and \"Solar Orbiter.\" L.V. acknowledges the financial support of the University of Turku Graduate School. E.P. acknowledges support from NASA's Parker Solar Probe Guest Investigators (PSP-GI; grant No. 80NSSC22K0349) program. N.W. acknowledges support from the Research Foundation—Flanders (FWO-Vlaanderen, fellowship No. 1184319N). A.K. acknowledges financial support from NASA NNN06AA01C (SO-SIS Phase-E, PSP EPI-Lo) contract. J.L.V. acknowledges support from NASA PSP-GI grant 80NSSC23K0208. The FIELDS experiment was developed and is operated under NASA contract NNN06AA01C.
\n\nThe study was initiated by I.C.J. and conceptualized together with O.V.A., V.V.K., and M.G. The methodologies for data analysis were provided by I.C.J., O.V.A., V.V.K., L.V., M.G., and E.P. Data analysis was performed by I.C.J., O.V.A., L.V., M.G., K.E.C., E.P., and A.K. The IS\u2299IS data were processed by J.G.M., L.V., C.M.S.C., N.D., and A.K. The SPAN-i data were prepared by J.V. and analyzed by I.C.J., O.V.A., L.V., and K.E.C. The results were interpreted by I.C.J., O.V.A., V.V.K., M.G., and R.V. The data were visualized by I.C.J., O.V.A., L.V., and K.E.C. I.C.J. wrote the manuscript and prepared the final draft. The final draft was prepared taking into account extensive comments from O.V.A., V.V.K., M.G., M.B., N.D., R.V., E.K.J., and S.D.B. All authors have agreed to the results presented in the manuscript.
",
"abstract": "\n
Collisionless shock waves, ubiquitous in the Universe, are crucial for particle acceleration in various astrophysical systems. Currently, the heliosphere is the only natural environment available for their in situ study. In this work, we showcase the collective acceleration of electrons and ions by one of the fastest in situ shocks ever recorded, observed by the pioneering Parker Solar Probe at only 34.5 million km from the Sun. Our analysis of this unprecedented, near-parallel shock shows electron acceleration up to 6 MeV amidst intense multiscale electromagnetic wave emissions. We also present evidence of a variable shock structure capable of injecting and accelerating ions from the solar wind to high energies through a self-consistent process. The exceptional capability of the probe's instruments to measure electromagnetic fields in a shock traveling at 1% the speed of light has enabled us, for the first time, to confirm that the structure of a strong heliospheric shock aligns with theoretical models of strong shocks observed in astrophysical environments. This alignment offers viable avenues for understanding astrophysical shock processes and the self-consistent acceleration of charged particles.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe acknowledge the support of NASA's Parker Solar Probe grant NNN06AA01C. We thank the Parker Solar Probe IS\u2299IS, FIELDS, and SWEAP teams, including the engineers, technicians, administrators, and scientists, who developed the instruments used in this study. The IS\u2299IS data and visualization tools are available to the community; 8 data are also available via the NASA Space Physics Data Facility. 9 We acknowledge the CCMC at Goddard Space Flight Center for the use of the DONKI database. 10
",
"abstract": "\n
High-energy neutral solar radiation in the form of γ-rays and neutrons is produced as secondary products in solar flares. The characteristics of this emission can provide key information regarding the energization of charged particles, particularly when primary particles remain trapped in the corona. The Integrated Science Investigation of the Sun (IS\u2299IS) suite on Parker Solar Probe is composed of instruments primarily intended to measure energetic charged particles. However, the High Energy Telescope (HET) in IS\u2299IS was also designed with a supplementary neutral mode intended to measure γ-rays and neutrons. HET observed its first clear solar γ-ray event in connection with a hard X-ray flare, the eruption of a coronal mass ejection, and a solar energetic particle event on 2022 September 5. The X-ray spectral shape was observed to harden over the course of the event, culminating with the observation of γ-rays by HET. A coincident enhancement in the lower-energy Energetic Particle Instrument (EPI-Lo) was also observed, likely produced by incident solar γ-rays despite the EPI-Lo instrument not having any special neutral measurement capabilities. We use Monte Carlo modeling to reconstruct the incident γ-ray spectrum based on the measured spectrum to demonstrate that the combination of IS\u2299IS instruments can measure hard X-rays and γ-rays from ∼60 keV–7 MeV. Despite the fact that this is a supplemental science goal of the mission, the capability of the IS\u2299IS instruments to measure γ-rays is important for the study of this population due to the very limited instruments currently observing the Sun in γ-rays.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nIXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2022-13-I.0, agreements ASI-INAF-2022-19-HH.0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, as well as by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC). This research has used the MAXI data provided by RIKEN, JAXA, and the MAXI team.
\nJ.S., M.D., J.Pod., and S.R.D. thank GACR project 21-06825X for the support and institutional support from RVO:67985815. A.V. thanks the Academy of Finland grant 355672 for support. Nordita is supported in part by NordForsk. The work of F.M., R.T., G.M., L.M., and P.S. is partially supported by the PRIN grant 2022LWPEXW of the Italian Ministry of University and Research (MUR). M.B. acknowledges the support from GAUK project No. 102323. A.I. acknowledges support from the Royal Society. T.M.-D. acknowledges support by the Spanish Agencia estatal de investigación via PID2021-124879NB-I00. The French contribution is supported by the French Space Agency (Centre National d'Etude Spatiale, CNES) and by the High Energy National Programme (PNHE) of the Centre National de la Recherche Scientifique (CNRS). Y.Z. acknowledges support from the Dutch Research Council (NWO) Rubicon Fellowship No. 019.231EN.021. F.C. acknowledges the support of the INAF grant 1.05.23.05.06: \"Spin and Geometry in accreting X-ray binaries: The first multi frequency spectro-polarimetric campaign.\" Finally, we thank the anonymous referee for the insightful comments that helped to improve the paper.
",
"abstract": "\n
Black hole X-ray binaries exhibit different spectral and timing properties in different accretion states. The X-ray outburst of a recently discovered and extraordinarily bright source, Swift J1727.8–1613, has enabled the first investigation of how the X-ray polarization properties of a source evolve with spectral state. The 2–8 keV polarization degree was previously measured by the Imaging X-ray Polarimetry Explorer (IXPE) to be ≈4% in the hard and hard intermediate states. Here we present new IXPE results taken in the soft state, with the X-ray flux dominated by the thermal accretion disk emission. We find that the polarization degree has dropped dramatically to \u22721%. This result indicates that the measured X-ray polarization is largely sensitive to the accretion state and the polarization fraction is significantly higher in the hard state when the X-ray emission is dominated by upscattered radiation in the X-ray corona. The combined polarization measurements in the soft and hard states disfavor a very high or low inclination of the system.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nParker Solar Probe: Insights into the Physics of the Near-Solar Environment
",
"abstract": "\n
On 2022 September 5, Parker Solar Probe (Parker) observed a large solar energetic particle (SEP) event at the unprecedented distance of only 15 RS from the Sun. The observations from the Integrated Science Investigation of the Sun (IS\u2299IS) obtained over the course of this event are remarkably rich, and an overview is presented here. IS\u2299IS is capable of measuring ions from 20 keV to over 100 MeV nuc−1 and electrons from 30 keV to 6 MeV; here, we primarily focus on the proton and helium measurements above 80 keV. Among the surprising results are evidence of inverse velocity dispersion at energies above 1 MeV during the onset of the event, a sharp decrease in the energetic particle intensities at all energies at the interplanetary shock crossing, and repeated short durations of highly anisotropic sunward flow. Many changes in the SEP intensities, anisotropy, and spectral steepness are coincident with solar wind structure boundaries identified using the Parker solar wind magnetic field and plasma data. However, there are significant changes that are not correlated with any clearly visible solar wind variation. The observations presented here serve as an introduction to a complex event with numerous opportunities for future, more in-depth studies.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThis work was supported by NASA at Caltech under a subaward of NASA grant 80NSSC21K1512 awarded to University of California, Berkeley for the IMPACT investigation, administered by Goddard Space Flight Center and by NASA grant 80NSSC19K0067. The CDAW CME catalog (https://cdaw.gsfc.nasa.gov/CME_list/) is generated and maintained at the CDAW Data Center by NASA and The Catholic University of America in cooperation with the Naval Research Laboratory. SOHO is a project of international cooperation between ESA and NASA. Measurements for Figure 3 and imagery for Figure 5 were made using JHelioviewer (Müller et al. 2017).
",
"abstract": "\n
Energetic neutral atoms (ENAs) are expected to be produced near the Sun during large solar energetic particle (SEP) events. However, their detection by SEP instruments near 1 au has been limited. The clearest reported measurement has been from the Solar Terrestrial Relations Observatory (STEREO) during the 2006 December 5 SEP event. Additional evidence of ENAs has been found through reanalysis of observations by the Solar Anomalous and Magnetospheric Particle Explorer obtained near the equator in low Earth orbit and associated with several large X-ray flares and fast coronal mass ejections (CMEs). Here we describe another detection of ENAs from the STEREO Low Energy Telescope associated with the large 2022 February 15 SEP event. Given the timing and spectrum of the ENAs and the location of the source region (behind the east limb from STEREO's viewpoint), these ENAs are most likely a result of acceleration by a CME-driven shock when the CME was at approximately 2–3 RS. The possibility of a postflare loop origin is considered unlikely.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the referee for the suggestions that helped to improve this paper. The authors would like to thank J. de Plaa for help with SPEX. This research has been supported by NASA's Astrophysics Data Analysis Program, grant No. 80NSSC20K0883, under the ROSES program NNH18ZDA001N. Support for this work was also provided by NASA through the Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 to MIT for support of the Chandra X-Ray Center (CXC) and science instruments. CXC is operated by SAO for and on behalf of NASA under contract NAS8-03060.
\n\n\n
\n
Some of the data presented in this article were obtained from the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute. The specific observations analyzed can be accessed via doi:10.17909/vdjz-xn16. This paper also employs a list of Chandra data sets, obtained by the Chandra X-ray Observatory, contained in doi:10.25574/cdc.202.
\n
\n
\n
In this study, we investigate interstellar absorption lines along the line of sight toward the galactic low-mass X-ray binary Cygnus X-2. We combine absorption line data obtained from high-resolution X-ray spectra collected with the Chandra and XMM-Newton satellites, along with far-UV absorption lines observed by the Hubble Space Telescope's (HST) Cosmic Origins Spectrograph (COS) instrument. Our primary objective is to understand the abundance and depletion of oxygen, iron, sulfur, and carbon. To achieve this, we have developed an analysis pipeline that simultaneously fits both the UV and X-ray data sets. This novel approach takes into account the line-spread function of HST/COS, enhancing the precision of our results. We examine the absorption lines of Fe ii, S ii, C ii, and C i present in the far-UV spectrum of Cygnus X-2, revealing the presence of at least two distinct absorbers characterized by different velocities. Additionally, we employ Cloudy simulations to compare our findings concerning the ionic ratios for the studied elements. We find that gaseous iron and sulfur exist in their singly ionized forms, Fe ii and S ii, respectively, while the abundances of C ii and C i do not agree with the Cloudy simulations of the neutral ISM. Finally, we explore discrepancies in the X-ray atomic data of iron and discuss their impact on the overall abundance and depletion of iron.
\n
© 2024 COSPAR. Published by Elsevier Under a Creative Commons license.
\n\n\n\n\n
We thank the four anonymous referees for their time and effort in reviewing this article. We acknowledge the COSPAR ISWAT community and their effort in organizing this special activity, in particular the dedicated endeavor of Masha Kuznetsova and Mario Bisi. J.G. is supported by the National Natural Science Foundation of China (grants 42188101, 42074222, 42130204) and the Strategic Priority Program of the Chinese Academy of Sciences (grant XDB41000000). B.W. was supported in part by a US National Science Foundation EPSCoR RII-Track-1 Cooperative Agreement (OIA-2148653). C.C. is supported by NASA grants NNN06AA01C, 80NSSC18K1446, 80NSSC18K0223, and JHU.APL173063. S.D. acknowledges support from the UK Natural Environment Research Council (grant NE/V002864/1) and the UK Science and Technology Facilities Council (grant ST/V000934/1). M.D. acknowledges support from the Croatian Science Foundation under the project IP-2020–02-9893 (ICOHOSS). L.W. is supported in part by the National Natural Science Foundation of China under contracts 42225404, 42127803, and 42150105. H.M.B. conducted this work while supported by Cooperative Agreement award NA17OAR4320101. The Integrated Solar Energetic Proton Alert/Warning System project transitioning SEP models to real-time operations and the development of the SEP Scoreboard is supported by the Advanced Exploration Systems Division under the Human Exploration and Operations Mission Directorate of NASA and is performed in support of the Human Health and Performance Contract for NASA (NNJ15HK11B). Part of the research described in this article was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA (80NM0018D0004).
\n\n
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
",
"abstract": "\n
\n
\n
Space weather is a multidisciplinary research area connecting scientists from across heliophysics domains seeking a coherent understanding of our space environment that can also serve modern life and society’s needs. COSPAR’s ISWAT (International Space Weather Action Teams) “clusters” focus attention on different areas of space weather study while ensuring the coupled system is broadly addressed via regular communications and interactions. The ISWAT H3 cluster “Radiation environment in heliosphere” (https://www.iswat-cospar.org/h3) has been working to provide a scientific platform to understand, characterize, and predict the energetic particle radiation in the heliosphere with the practical goal of mitigating radiation risks associated with areospace activities, the satellite industry, and human space explorations. In particular, present approaches help us understand the physical phenomena at large, optimizing the output of multiviewpoint observations and pushing current models to their limits. In this article, we review the scientific aspects of the radiation environment in the heliosphere, covering four different radiation types: solar energetic particles, ground-level enhancement (a type of solar energetic particle event with energies high enough to trigger signals in ground-level detectors), galactic cosmic rays, and anomalous cosmic rays. We focus on related advances in the research community in the past 10–20 years and what we still lack in terms of understanding and predictive capabilities. Finally, we also consider some recommendations related to the improvement of both observational and modeling capabilities in the field of the space radiation environment.
\n
\n
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThis work was supported by the Natural Science Foundation of Shanghai, grant No. 22ZR1403400, the National Natural Science Foundation of China (NSFC), grant Nos. 12250610185, 11973019, and 12261131497, and the Shanghai Municipal Education Commission, grant No. 2019-01-07-00-07-E00035. T.M. acknowledges also the support from the China Scholarship Council (CSC), grant No. 2022GXZ005433. S.R. acknowledges also the support from the China Postdoctoral Science Foundation, grant No. 2022M720035, and the Teach@Tübingen Fellowship. J.J. acknowledges support from the Leverhulme Trust, Isaac Newton Trust and St Edmund's College, University of Cambridge.
",
"abstract": "Abstract\n We present a new model to calculate reflection spectra of thin accretion disks in Kerr spacetimes. Our model includes the effect of returning radiation, which is the radiation that is emitted by the disk and returns to the disk because of the strong light bending near a black hole. The major improvement with respect to the existing models is that it calculates the reflection spectrum at every point on the disk by using the actual spectrum of the incident radiation. Assuming a lamppost coronal geometry, we simulate simultaneous observations of NICER and NuSTAR of bright Galactic black holes and we fit the simulated data with the latest version of relxill (modified to read the table of reflionx, which is the nonrelativistic reflection model used in our calculations). We find that relxill with returning radiation cannot fit well the simulated data when the black hole spin parameter is very high and the coronal height and disk's ionization parameter are low, and some parameters can be significantly overestimated or underestimated. We can find better fits and recover the correct input parameters as the value of the black hole spin parameter decreases and the value of the coronal height increases.",
"date": "2024-04-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "965",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "66",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/g33ae-8hz36",
"funders": {
"items": [
{
"grant_number": "22ZR1403400"
},
{
"grant_number": "12250610185"
},
{
"grant_number": "11973019"
},
{
"grant_number": "12261131497"
},
{
"grant_number": "2019-01-07-00-07-E00035"
},
{
"grant_number": "2022GXZ005433"
},
{
"grant_number": "2022M720035"
},
{},
{},
{},
{}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ad303b",
"primary_object": {
"basename": "Mirzaev_2024_ApJ_965_66.pdf",
"url": "https://authors.library.caltech.edu/records/g33ae-8hz36/files/Mirzaev_2024_ApJ_965_66.pdf"
},
"pub_year": "2024",
"author_list": "Mirzaev, Temurbek; Riaz, Shafqat; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0ep0c-zra90",
"eprint_status": "archive",
"datestamp": "2024-03-19 22:07:50",
"lastmod": "2024-03-19 22:07:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Homan-Jeroen",
"name": {
"family": "Homan",
"given": "Jeroen"
},
"orcid": "0000-0001-8371-2713"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Altamirano-Diego",
"name": {
"family": "Altamirano",
"given": "Diego"
},
"orcid": "0000-0002-3422-0074"
},
{
"id": "Belloni-Tomaso",
"name": {
"family": "Belloni",
"given": "Tomaso"
},
"orcid": "0000-0001-9621-3796"
},
{
"id": "van-der-Klis-Michiel",
"name": {
"family": "van der Klis",
"given": "Michiel"
},
"orcid": "0000-0003-0070-9872"
},
{
"id": "Ingram-Adam",
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Connors-Riley",
"name": {
"family": "Connors",
"given": "Riley"
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Lucchini-Matteo",
"name": {
"family": "Lucchini",
"given": "Matteo"
},
"orcid": "0000-0002-2235-3347"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Neilsen-Joseph",
"name": {
"family": "Neilsen",
"given": "Joseph"
},
"orcid": "0000-0002-8247-786X"
},
{
"id": "Lewin-Collin",
"name": {
"family": "Lewin",
"given": "Collin"
},
"orcid": "0000-0002-8671-1190"
},
{
"id": "Remillard-Ron-A",
"name": {
"family": "Remillard",
"given": "Ron A."
},
"orcid": "0000-0003-4815-0481"
}
]
},
"title": "Highly Coherent Quasiperiodic Oscillations in the \"Heartbeat\" Black Hole X-Ray Binary IGR J17091\u20133624",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank Keith Gendreau, Zaven Arzoumanian, and Elizabeth Ferrara for scheduling and performing the NICER observations. J.W. acknowledges support from the NASA FINESST Graduate Fellowship, under grant 80NSSC22K1596. J.W. thanks Gibwa Musoke, Megan Masterson, Mason Ng, Navin Sridhar, and Yerong Xu for useful discussions. J.W., E.K., J.A.G., G.M., and M.L. acknowledge support from NASA ADAP grant 80NSSC17K0515. A.I. and D.A. acknowledge support from the Royal Society. T.B. acknowledges the financial contribution from PRIN INAF 2019 n.15.
",
"abstract": "\n
IGR J17091–3624 is a black hole X-ray binary (BHXB), often referred to as the \"twin\" of GRS 1915+105 because it is the only other known BHXB that can show exotic \"heartbeat\"-like variability that is highly structured and repeated. Here, we report on observations of IGR J17091–3624 from its 2022 outburst, where we detect an unusually coherent quasiperiodic oscillation (QPO) when the broadband variability is low (total fractional rms \u22726%) and the spectrum is dominated by the accretion disk. Such spectral and variability behavior is characteristic of the soft state of typical BHXBs (i.e., those that do not show heartbeats), but we also find that this QPO is strongest when there is some exotic heartbeat-like variability (so-called Class V variability). This QPO is detected at frequencies between 5 and 8 Hz and has Q factors (defined as the QPO frequency divided by the width) \u227350, making it one of the most highly coherent low-frequency QPOs ever seen in a BHXB. The extremely high Q factor makes this QPO distinct from typical low-frequency QPOs that are conventionally classified into type-A/B/C QPOs. Instead, we find evidence that archival observations of GRS 1915+105 also showed a similarly high-coherence QPO in the same frequency range, suggesting that this unusually coherent and strong QPO may be unique to BHXBs that can exhibit \"heartbeat\"-like variability.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
This work is a product of a community effort to investigate the 2022 February 15–16 event under the coordination of an active working group and a best-effort basis collaboration between scientists from the missions involved in this work. It has benefited tremendously from many helpful discussions and from the collaborative spirit within its members.
\n
L.Y.K. acknowledges support through IS\u2299IS funding. B.S.-C. acknowledges support through STFC Ernest Rutherford Fellowship ST/V004115/1 and grant ST/Y000439/1. C.O.L. acknowledges support from the MAVEN project funded through the NASA Mars Exploration Program, the NASA LWS grants 80NSSC21K1325 and 80NSSC21K0119, and the NASA MDAP grant 80NSSC19K1224. L.R.-G. acknowledges the financial support by the Spanish Ministerio de Ciencia, Innovación y Universidades FEDER/MCIU/AEI Project PID2019-104863RB-I00/AEI/10.13039/501100011033 and by the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004159 (SERPENTINE). A.K. acknowledges financial support from NASA NNN06AA01C (SO-SIS Phase-E, PSP EPI-Lo) contract. E.P. acknowledges support from NASA's PSP-GI (No. 80NSSC22K0349), O2R (No. 80NSSC20K0285), LWS (No. 80NSSC19K0067), and LWS-SC (No. 80NSSC22K0893) programs. F.C. acknowledges the financial support by an appointment to the NASA Postdoctoral Program at the NASA Goddard Space Flight Center, administered by ORAU through a contract with NASA, and the support of the Solar Orbiter mission. N.D., I.C.J., and A.F. are grateful for support by the Academy of Finland (SHOCKSEE, grant No. 346902). T.N.-C. acknowledges support through the Solar Orbiter mission (NASA). B.E. and the MSL/RAD data analysis are supported by NASA (SMD/Heliophysics and HEOMD/AES) under JPL subcontract #1273039 to Southwest Research Institute. V.K. received support from the STEREO/Waves and Wind/Waves projects.
\n
We gratefully thank everyone who helped make the IS\u2299IS instrument suite and PSP mission possible. The IS\u2299IS data and visualization tools are available at https://spacephysics.princeton.edu/missions-instruments/isois. PSP was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). We are also thankful to the BepiColombo MAG and BERM teams who provided the data and assisted the data interpretation. Solar Orbiter is a space mission of international collaboration between ESA and NASA, operated by ESA. SOHO is a project of international cooperation between ESA and NASA. LASCO was constructed by a consortium of institutions: the Naval Research Laboratory (Washington, DC, USA), the Max-Planck-Institut fur Aeronomie (Katlenburg-Lindau, Germany), the Laboratoire d'Astronomie Spatiale (Marseille, France), and the University of Birmingham (Birmingham, UK).
\n
ENLIL simulation results have been provided by the CCMC at NASA Goddard Space Flight Center (GSFC) through their public Runs-on-Request system (http://ccmc.gsfc.nasa.gov; run ID Christina_Lee_101722_SH_1). The WSA model was developed by N. Arge, currently at NASA/GSFC, and the ENLIL Model was developed by D. Odstrcil, currently at George Mason University. Finally, L.Y.K. would like to thank the Princeton Space Physics research group for their useful suggestions and feedback that helped improve the quality of this article.
\n
Parker Solar Probe: Insights into the Physics of the Near-Solar Environment
",
"abstract": "\n
On 2022 February 15–16, multiple spacecraft measured one of the most intense solar energetic particle (SEP) events observed so far in Solar Cycle 25. This study provides an overview of interesting observations made by multiple spacecraft during this event. Parker Solar Probe (PSP) and BepiColombo were close to each other at 0.34–0.37 au (a radial separation of ∼0.03 au) as they were impacted by the flank of the associated coronal mass ejection (CME). At about 100° in the retrograde direction and 1.5 au away from the Sun, the radiation detector on board the Curiosity surface rover observed the largest ground-level enhancement on Mars since surface measurements began. At intermediate distances (0.7–1.0 au), the presence of stream interaction regions (SIRs) during the SEP arrival time provides additional complexities regarding the analysis of the distinct contributions of CME-driven versus SIR-driven events in observations by spacecraft such as Solar Orbiter and STEREO-A, and by near-Earth spacecraft like ACE, SOHO, and WIND. The proximity of PSP and BepiColombo also enables us to directly compare their measurements and perform cross-calibration for the energetic particle instruments on board the two spacecraft. Our analysis indicates that energetic proton measurements from BepiColombo and PSP are in reasonable agreement with each other to within a factor of ∼1.35. Finally, this study introduces the various ongoing efforts that will collectively improve our understanding of this impactful, widespread SEP event.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nE.P. acknowledges support from NASA's Parker Solar Probe Guest Investigators (PSP-GI; No. 80NSSC22K0349), Heliophysics Theory, Modeling, and Simulations (HTMS; No. 80NSSC20K1274), and Living With a Star Strategic Capabilities (LWS-SC; No. 80NSSC22K0893) programs, as well as Parker Solar Probe WISPR contract No. NNG11EK11I to NRL (under subcontract No. N00173-19-C-2003 to PSI). F.C., S.P., and A.J.W. acknowledge the financial support by an appointment to the NASA Postdoctoral Program at the NASA Goddard Space Flight Center, administered by USRA through a contract with NASA. B.S.-C. acknowledges support from the UK-STFC Ernest Rutherford fellowship ST/V004115/1 and the BepiColombo guest investigator grant ST/Y000439/1. B.J.L. acknowledges support from NASA HSR No. 80NSSC20K1448 and HGI No. 80NSSC21K0731. B.J.L. and C.O.L. acknowledge NASA LWS grant No. 80NSSC21K1325. D.L. acknowledges support from NASA Living With a Star (LWS) program NNH19ZDA001N-LWS. A.N.Z., L.R., and M.M. thank the Belgian Federal Science Policy Office (BELSPO) for the provision of financial support in the framework of the PRODEX Programme of the European Space Agency (ESA) under contract Nos. 4000112292, 4000134088, 4000134474, and 4000136424. L.R.-G. acknowledges the financial support by the Spanish Ministerio de Ciencia, Innovación y Universidades FEDER/MCIU/AEI Projects ESP2017-88436-R and PID2019-104863RB-I00/AEI/10.13039/501100011033. L.R.-G. and N.D. acknowledge support by the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004159 (SERPENTINE). N.D. also acknowledges funding from the Academy of Finland (SHOCKSEE, grant No. 346902).
\nBepiColombo is an ESA–JAXA mission, where MPO has been built and is operated by ESA.
\nParker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's LWS program (contract No. NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission.
\nSolar Orbiter is a space mission of international collaboration between ESA and NASA, operated by ESA. The EUI instrument was built by CSL, IAS, MPS, MSSL/UCL, PMOD/WRC, ROB, and LCF/IO with funding from the Belgian Federal Science Policy Office; the Centre National dEtudes Spatiales (CNES); the UK Space Agency (UKSA); the Bundesministerium für Wirtschaft und Energie (BMWi) through the Deutsches Zentrum für Luft- und Raumfahrt (DLR); and the Swiss Space Office (SSO).
\n\nBepi (MPO-MAG); - GOES (SUVI); Parker (FIELDS, SWEAP, WISPR); SOHO (LASCO); SolO (EUI); STEREO (SECCHI)
\n\nAstroPy (Astropy Collaboration et al. 2022); SolarSoft (Freeland & Handy 1998); SunPy (SunPy Community et al. 2020)
\n\nParker Solar Probe: Insights into the Physics of the Near-Solar Environment
",
"abstract": "\n
On 2022 February 15, an impressive filament eruption was observed off the solar eastern limb from three remote-sensing viewpoints, namely, Earth, STEREO-A, and Solar Orbiter. In addition to representing the most-distant observed filament at extreme ultraviolet wavelengths—captured by Solar Orbiter's field of view extending to above 6 R\u2299—this event was also associated with the release of a fast (∼2200 km s−1) coronal mass ejection (CME) that was directed toward BepiColombo and Parker Solar Probe. These two probes were separated by 2° in latitude, 4° in longitude, and 0.03 au in radial distance around the time of the CME-driven shock arrival in situ. The relative proximity of the two probes to each other and the Sun (∼0.35 au) allows us to study the mesoscale structure of CMEs at Mercury's orbit for the first time. We analyze similarities and differences in the main CME-related structures measured at the two locations, namely, the interplanetary shock, the sheath region, and the magnetic ejecta. We find that, despite the separation between the two spacecraft being well within the typical uncertainties associated with determination of CME geometric parameters from remote-sensing observations, the two sets of in situ measurements display some profound differences that make understanding the overall 3D CME structure particularly challenging. Finally, we discuss our findings within the context of space weather at Mercury's distance and in terms of the need to investigate solar transients via spacecraft constellations with small separations, which has been gaining significant attention during recent years.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
We thank Keith Gendreau, Zaven Arzoumanian, Elizabeth Ferrara, Karl Forster, and Pat Slane for scheduling and performing the observations. J.W. acknowledges support from the NASA FINESST Graduate Fellowship, under grant 80NSSC22K1596. J.W. thanks Gibwa Musoke, Megan Masterson, Mason Ng, Navin Sridhar, and Yerong Xu for useful discussions. J.W., E.K., J.A.G., G.M., and M.L. acknowledge support from NASA ADAP grant 80NSSC17K0515. A.I. and D.A. acknowledge support from the Royal Society. M.K. acknowledges support from an NWO Spinoza prize.
\n
We dedicate this series of papers to the late Tomaso Belloni, who contributed significantly to these papers before his untimely passing on 2023 August 26. Tomaso was a pioneer in the study of X-ray timing, since his early days working on EXOSAT, and, in particular, he awakened the community to the beautiful puzzle that is GRS 1915. In this work, on GRS 1915's \"little sister,\" IGR J17091, we build upon the legacy of a trailblazer in our field. We will miss him for his energy, his insights, his humor, and his unwavering passion for science. Ad astra, Tomaso.
",
"abstract": "\n
While the standard X-ray variability of black hole X-ray binaries (BHXBs) is stochastic and noisy, there are two known BHXBs that exhibit exotic \"heartbeat\"-like variability in their lightcurves: GRS 1915+105 and IGR J17091–3624. In 2022, IGR J17091–3624 went into outburst for the first time in the NICER/NuSTAR era. These exquisite data allow us to simultaneously track the exotic variability and the corresponding spectral features with unprecedented detail. We find that as in typical BHXBs, the outburst began in the hard state, then continued in the intermediate state, but then transitioned to an exotic soft state, where we identify two types of heartbeat-like variability (Class V and a new Class X). The flux energy spectra show a broad iron emission line due to relativistic reflection when there is no exotic variability, and absorption features from highly ionized iron when the source exhibits exotic variability. Whether absorption lines from highly ionized iron are detected in IGR J17091–3624 is not determined by the spectral state alone, but rather is determined by the presence of exotic variability; in a soft spectral state, absorption lines are only detected along with exotic variability. Our finding indicates that IGR J17091–3624 can be seen as a bridge between the most peculiar BHXB GRS 1915+105 and \"normal\" BHXBs, because it alternates between the conventional and exotic behaviors of BHXBs. We discuss the physical nature of the absorbing material and exotic variability in light of this new legacy data set.
\n
© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
This work has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004159 (SERPENTINE, www.serpentine-h2020.eu). A.L. is supported by STFC Consolidated grant ST/T00018X/1. C.H.K.C. is supported by UKRI Future Leaders Fellowship MR/W007657/1 and STFC Consolidated Grants ST/T00018X/1 and ST/X000974/1. H.H. is supported by the Royal Society University Research Fellowship URF/R1/180671. N.D. is grateful for support by the Academy of Finland (SHOCKSEE, grant No. 346902). The PSP/FIELDS experiment was developed and is operated under NASA contract NNN06AA01C. Work at IRAP is supported by CNRS, UPS, and CNES. E.E.D acknowledges funding by the European Union (ERC, HELIO4CAST, 101042188). Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. X.B.C. is grateful for PAPIIT DGAPA grant IN110921. This work was supported by the UK Science and Technology Facilities Council (STFC) grant ST/W001071/1. L.F. is supported by the Royal Society University Research Fellowship No. URF\\R1\\231710. R.F.W.S. thanks the German Space Agency (DLR) for its support of SOLO/EPD under grant 50OT2002.
\n
Parker Solar Probe: Insights into the Physics of the Near-Solar Environment
",
"abstract": "\n
The Parker Solar Probe (PSP) and Solar Orbiter (SolO) missions opened a new observational window in the inner heliosphere, which is finally accessible to direct measurements. On 2022 September 5, a coronal mass ejection (CME)-driven interplanetary (IP) shock was observed as close as 0.07 au by PSP. The CME then reached SolO, which was radially well-aligned at 0.7 au, thus providing us with the opportunity to study the shock properties at different heliocentric distances. We characterize the shock, investigate its typical parameters, and compare its small-scale features at both locations. Using the PSP observations, we investigate how magnetic switchbacks and ion cyclotron waves are processed upon shock crossing. We find that switchbacks preserve their V–B correlation while compressed upon the shock passage, and that the signature of ion cyclotron waves disappears downstream of the shock. By contrast, the SolO observations reveal a very structured shock transition, with a population of shock-accelerated protons of up to about 2 MeV, showing irregularities in the shock downstream, which we correlate with solar wind structures propagating across the shock. At SolO, we also report the presence of low-energy (∼100 eV) electrons scattering due to upstream shocklets. This study elucidates how the local features of IP shocks and their environments can be very different as they propagate through the heliosphere.
\n
© 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.
\n\n
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
\n
This work was supported by the National Natural Science Foundation of China (NSFC), Grant No. 12250610185, 11973019, and 12261131497, the Shanghai Municipal Education Commission, Grant No. 2019-01-07-00-07-E00035, the Natural Science Foundation of Shanghai, Grant No. 22ZR1403400, and Fudan University, Grant No. JIH1512604. GM acknowledges also the support from the China Scholarship Council (CSC), Grant No. 2020GXZ016647.
\n\nThis work used the data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
",
"abstract": "The development of techniques to measure accurately black hole spins is crucial to study the physics and astrophysics of these objects. X-ray reflection spectroscopy is currently the most popular method to estimate the spins of accreting black holes; so far it has provided a spin measurement of about 40 stellar-mass black holes in X-ray binaries and 40 supermassive black holes in active galactic nuclei. The relativistic precession model (RPM) is another method to measure the spins of stellar-mass black holes: it requires the measurement of the frequencies of three simultaneous quasi-periodic oscillations and can potentially provide precise estimates of the black hole mass and spin. However, the two methods do not seem to provide consistent results when applied to the same sources, which questions the reliability and accuracy of these measurements. Recently, the RPM has been applied to infer the spin of the black hole in XTE J1859+226. The authors found a* = 0.149 ± 0.005 (68 per cent CL). There are no other spin measurements of this source. We looked for archived RXTE observations of XTE J1859+226 with blurred reflection features and found 23 spectra suitable for measuring the spin. We employed two different models with relxill and relxillD and obtained a higher spin value from all these fits. From simultaneous fitting of seven spectra of higher quality, we found $a_* = 0.986^{+0.001}_{-0.004}$ and a* = 0.987 ± 0.003 (90 per cent CL, statistical) with relxill and relxillD, respectively. Our results confirm the discrepancy between the spin measurements inferred from the two techniques.
",
"date": "2024-02",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "527",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "12053-12064",
"issn": "0035-8711",
"official_url": "https://authors.library.caltech.edu/records/zm9k0-pvb36",
"funders": {
"items": [
{
"grant_number": "12250610185"
},
{
"grant_number": "11973019"
},
{
"grant_number": "12261131497"
},
{
"grant_number": "2019-01-07-00-07-E00035"
},
{
"grant_number": "22ZR1403400"
},
{
"grant_number": "JIH1512604"
},
{
"grant_number": "2020GXZ016647"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stad3933",
"primary_object": {
"basename": "stad3933.pdf",
"url": "https://authors.library.caltech.edu/records/zm9k0-pvb36/files/stad3933.pdf"
},
"pub_year": "2024",
"author_list": "Mall, Gitika; Liu, Honghui; et al."
},
{
"id": "https://authors.library.caltech.edu/records/frszs-70f17",
"eprint_status": "archive",
"datestamp": "2024-02-02 19:17:30",
"lastmod": "2024-02-02 19:17:30",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kaaret-Philip",
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Silvestri",
"given": "Stefano"
},
"orcid": "0000-0002-8665-0105"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Safi-Harb",
"given": "Samar"
},
"orcid": "0000-0001-6189-7665"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Veledina",
"given": "Alexandra"
},
"orcid": "0000-0002-5767-7253"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Cibrario",
"given": "Nicol\u00f2"
},
"orcid": "0000-0003-3842-4493"
},
{
"name": {
"family": "Mac Intyre",
"given": "Brydyn"
}
},
{
"name": {
"family": "Mikus\u0306incov\u00e1",
"given": "Romana"
},
"orcid": "0000-0001-7374-843X"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"name": {
"family": "Svoboda",
"given": "Jiri"
},
"orcid": "0000-0003-2931-0742"
},
{
"name": {
"family": "Tugliani",
"given": "Stefano"
},
"orcid": "0000-0002-3318-9036"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Ng",
"given": "Chi-Yung"
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "X-Ray Polarization of the Eastern Lobe of SS 433",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC), and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. A.V. acknowledges support from the Academy of Finland grant 355672.
\n\nIXPE - , XMM-Newton - , NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission
\n\nixpeobssim (Baldini et al. 2022), xspec (Arnaud1996), ds9 (Smithsonian Astrophysical Observatory 2000), astropy (Astropy Collaboration et al. 2013)
",
"abstract": "\n
How astrophysical systems translate the kinetic energy of bulk motion into the acceleration of particles to very high energies is a pressing question. SS 433 is a microquasar that emits TeV γ-rays indicating the presence of high-energy particles. A region of hard X-ray emission in the eastern lobe of SS 433 was recently identified as an acceleration site. We observed this region with the Imaging X-ray Polarimetry Explorer and measured a polarization degree in the range 38%–77%. The high polarization degree indicates the magnetic field has a well-ordered component if the X-rays are due to synchrotron emission. The polarization angle is in the range −12° to +10° (east of north), which indicates that the magnetic field is parallel to the jet. Magnetic fields parallel to the bulk flow have also been found in supernova remnants and the jets of powerful radio galaxies. This may be caused by interaction of the flow with the ambient medium.
\n
© 2024 Brightman, Margutti, Polzin, Jaodand, Hotokezaka, Alford, Hallinan, Kammoun, Mooley, Masterson, Marcotulli, Rau, Wevers, Younes, Stern, García and Madsen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
\n\n\n
The author(s) declare financial support was received for the research, authorship, and/or publication of this article. The work of DS was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. EK acknowledges financial support from the Centre National d?Etudes Spatiales (CNES). GH and KM acknowledge support from the National Science Foundation Grant AST-1911199.
\n
HEX-P is a probe-class mission concept that will combine high spatial resolution X-ray imaging (<10′′ FWHM) and broad spectral coverage (0.2–80 keV) with an effective area superior to NuSTAR above 10 keV to enable revolutionary new insights into a variety of astrophysical problems, especially those related to compact objects, accretion and outflows. HEX-P will launch at a time when the sky is being routinely scanned for transient gravitational wave, electromagnetic and neutrino phenomena that will require the capabilities of a sensitive, broadband X-ray telescope for follow up studies. These include the merger of compact objects such as neutron stars and black holes, stellar explosions, and the birth of new compact objects. A response time to target of opportunity observation requests of <24 hours and a field of regard of 3π steradians will allow HEX-P to probe the accretion and ejecta from these transient phenomena through the study of relativistic outflows and reprocessed emission, provide unique capabilities for understanding jet physics, and potentially revealing the nature of the central engine.
",
"date": "2024-01-09",
"date_type": "published",
"publication": "Frontiers in Astronomy and Space Sciences",
"volume": "10",
"publisher": "Frontiers Media SA",
"pagerange": "1292656",
"issn": "2296-987X",
"official_url": "https://authors.library.caltech.edu/records/adtc3-xv586",
"funders": {
"items": [
{},
{},
{
"grant_number": "AST-1911199"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
},
{
"id": "Owens-Valley-Radio-Observatory"
}
]
},
"doi": "10.3389/fspas.2023.1292656",
"primary_object": {
"basename": "fspas-10-1292656.pdf",
"url": "https://authors.library.caltech.edu/records/adtc3-xv586/files/fspas-10-1292656.pdf"
},
"pub_year": "2024",
"author_list": "Brightman, Murray; Margutti, Raffaella; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jntd1-93p75",
"eprint_status": "archive",
"datestamp": "2024-01-10 18:47:45",
"lastmod": "2024-01-10 18:47:45",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Svoboda-Ji\u0159\u00ed",
"name": {
"family": "Svoboda",
"given": "Ji\u0159\u00ed"
},
"orcid": "0000-0003-2931-0742"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"name": {
"family": "Yilmaz",
"given": "Anastasiya"
},
"orcid": "0000-0003-1133-1684"
},
{
"name": {
"family": "Rodriguez Cavero",
"given": "Nicole"
},
"orcid": "0000-0001-5256-0278"
},
{
"name": {
"family": "Marra",
"given": "Lorenzo"
},
"orcid": "0009-0001-4644-194X"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Veledina",
"given": "Alexandra"
},
"orcid": "0000-0002-5767-7253"
},
{
"name": {
"family": "Mojaver",
"given": "Mehrnoosh Rahbardar"
},
"orcid": "0000-0002-9633-0359"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Podgorn\u00fd",
"given": "Jakub"
},
"orcid": "0000-0001-5418-291X"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Brigitte",
"given": "Maimouna"
},
"orcid": "0009-0004-1197-5935"
},
{
"name": {
"family": "Bursa",
"given": "Michal"
},
"orcid": "0000-0003-0167-1888"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Hu",
"given": "Kun"
},
"orcid": "0000-0002-9705-7948"
},
{
"name": {
"family": "Chun",
"given": "Sohee"
},
"orcid": "0009-0002-2488-5272"
},
{
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"name": {
"family": "Mikus\u0306incov\u00e1",
"given": "Romana"
},
"orcid": "0000-0001-7374-843X"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Ursini",
"given": "Francesco"
},
"orcid": "0000-0001-9442-7897"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladim\u00edr"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Ng",
"given": "Chi-Yung"
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
}
]
},
"title": "First X-Ray Polarization Measurement Confirms the Low Black Hole Spin in LMC X-3",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2022-13-I.0, agreements ASI-INAF-2022-19-HH.0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester.
\nThe authors thank the referee for insightful comments and suggestions. J.S., M.D., J.P., M.B., and V.K. thank GACR project 21-06825X for the support and institutional support from RVO:67985815. A.Y. and M.B. acknowledge the support from GAUK project No. 102323. A.I. acknowledges support from the Royal Society. A.V. thanks the Academy of Finland grant 355672 for support. P.-O.P. acknowledges financial support from the French Space Agency (CNES) and the French High Energy National Programme (PNHE) of CNRS. N.R.C., M.R.M., H.K., K.H., and S.C. acknowledge support by NASA grants 80NSSC22K1291, 80NSSC23K1041, and 80NSSC20K0329.
\n\nIXPE - , NICER - , NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift - Swift Gamma-Ray Burst Mission
",
"abstract": "\n
X-ray polarization is a powerful tool to investigate the geometry of accreting material around black holes, allowing independent measurements of the black hole spin and orientation of the innermost parts of the accretion disk. We perform X-ray spectropolarimetric analysis of an X-ray binary system in the Large Magellanic Cloud, LMC X-3, that hosts a stellar-mass black hole, known to be persistently accreting since its discovery. We report the first detection of the X-ray polarization in LMC X-3 with the Imaging X-ray Polarimetry Explorer, and find the average polarization degree (PD) of 3.2% ± 0.6% and a constant polarization angle of −42° ± 6° over the 2–8 keV range. Using accompanying spectroscopic observations by NICER, NuSTAR, and the Neil Gehrels Swift observatories, we confirm previous measurements of the black hole spin via the X-ray continuum method, a ≈ 0.2. From polarization analysis only, we found consistent results with low black hole spin, with an upper limit of a < 0.7 at a 90% confidence level. A slight increase in the PD with energy, similar to other black hole X-ray binaries in the soft state, is suggested from the data but with a low statistical significance.
\n
© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the referee for comments, which helped us improve the quality of our manuscript. We acknowledge support from the National Science Foundation of China 11721303, 11991052, 12011540375, and 12233001 (L.H.); the National Key R&D Program of China 2022YFF0503401 (L.H.); the China Manned Space Project CMS-CSST-2021-A04 and CMS-CSST-2021-A06 (L.H.); Fondecyt Regular grant 1230345 (C.R.) and ANID BASAL project FB210003 (C.R., F.E.B., E.T.); NASA through ADAP award NNH16CT03C (M.K.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program through grant agreement No. 950533 (B.T.); Fondecyt fellowship No. 3220516 (M.T.); the Korea Astronomy and Space Science Institute under the R&D program (project No. 2022-1-868-04) supervised by the Ministry of Science and ICT (K.O.); the National Research Foundation of Korea (NRF-2020R1C1C1005462) (K.O.); Fondecyt Postdoctorado 3210157 (A.R.); RIN MIUR 2017 project \"Black Hole winds and the Baryon Life Cycle of Galaxies: the stone-guest at the galaxy evolution supper,\" contract 2017PH3WAT (F.R.); the ANID—Millennium Science Initiative Program—ICN12_009 (F.E.B.); CATA-Basal—ACE210002 (F.E.B., E.T.); FONDECYT Regular—1190818 (F.E.B., E.T.) and 1200495 (F.E.B., E.T.); Núcleo Milenio NCN_058 (E.T.); the Science Fund of the Republic of Serbia, PROMIS 6060916, BOWIE; and the Ministry of Education, Science and Technological Development of the Republic of Serbia through contract No. 451-03-9/2023-14/200002 (M.S.). This work made use of data from the NASA/IPAC Infrared Science Archive and NASA/IPAC Extragalactic Database (NED), which are operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory.
\n\nSwift - Swift Gamma-Ray Burst Mission, WISE - Wide-field Infrared Survey Explorer, IRAS - InfraRed Astronomical Satellite, Akari - Akari (ASTRO-F), Spitzer - Spitzer Space Telescope satellite
",
"abstract": "\n
Accreting supermassive black holes (SMBHs) located at the centers of galaxies are typically surrounded by large quantities of gas and dust. The structure and evolution of this circumnuclear material can be studied at different wavelengths, from the submillimeter to the X-ray. Recent X-ray studies have shown that the covering factor of the obscuring material tends to decrease with increasing Eddington ratio, likely due to radiative feedback on dusty gas. Here we study a sample of 549 nearby (z \u2272 0.1) hard X-ray (14–195 keV) selected nonblazar active galactic nuclei (AGN) and use the ratio between the AGN infrared and bolometric luminosity as a proxy of the covering factor. We find that, in agreement with what has been found by X-ray studies of the same sample, the covering factor decreases with increasing Eddington ratio. We also confirm previous findings that showed that obscured AGN typically have larger covering factors than unobscured sources. Finally, we find that the median covering factors of AGN located in different regions of the column density–Eddington ratio diagram are in good agreement with what would be expected from a radiation-regulated growth of SMBHs.
\n
\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe authors thank the anonymous referee for constructive feedback that improved the manuscript. B.O. and C.K. acknowledge support from multiple grants to follow-up DGPS sources: NASA grants 80NSSC17K0335, 80NSSC20K0389, 80NSSC19K0916, 80NSSC22K1398, and 80NSSC22K0583, Chandra awards GO9-20057X and GO2-23038X, and award number 46939-1-CCNS 22317F. P.B.'s research was supported by a grant (No. 2020747) from the United States\u2013Israel Binational Science Foundation (BSF), Jerusalem, Israel. J.H. and Z.W. acknowledge support from NASA under award No. 80GSFC21M0002.
This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. This research has made use of the VizieR catalog access tool, CDS, Strasbourg, France (https://vizier.cds.unistra.fr). The original description of the VizieR service was published in Ochsenbein et al. (2000). This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France. This research has made use of data obtained from the Chandra Source Catalog, provided by the Chandra X-ray Center (CXC) as part of the Chandra Data Archive. This research has made use of data obtained from the 4XMM XMM-Newton serendipitous source catalog compiled by the 10 institutes of the XMM-Newton Survey Science Centre selected by ESA. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
\n\nSwift (XRT) - Swift Gamma-Ray Burst Mission
\n\nHEASoft, XRTDAS, swifttools (Evans et al. 2023), PIMMS, Astropy (Astropy Collaboration et al. 2013)
",
"abstract": "The Swift Deep Galactic Plane Survey (DGPS) is a Swift Key Project consisting of 380 tiled pointings covering \u223c40 deg\u00b2 of the Galactic plane between longitude 10 < \u2223l\u2223 < 30 deg and latitude \u2223b\u2223 < 0.5 deg. Each pointing has a 5 ks exposure, yielding a total of 1.9 Ms spread across the entire survey footprint. Phase I observations were carried out between 2017 March and 2021 May. The survey is complete to depth L\u2093 > 10\u00b3\u2074 erg s\u207b\u00b9 to the edge of the Galaxy. The main survey goal is to produce a rich sample of new X-ray sources and transients, while also covering a broad discovery space. Here, we introduce the survey strategy and present a catalog of sources detected during Phase I observations. In total, we identify 928 X-ray sources, of which 348 are unique to our X-ray catalog. We report on the characteristics of sources in our catalog and highlight sources newly classified and published by the DGPS team.
",
"date": "2023-12",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "269",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "49",
"issn": "0067-0049",
"official_url": "https://authors.library.caltech.edu/records/0zbk7-kzt20",
"funders": {
"items": [
{
"grant_number": "80NSSC17K0335"
},
{
"grant_number": "80NSSC20K0389"
},
{
"grant_number": "80NSSC19K0916"
},
{
"grant_number": "80NSSC22K0583"
},
{
"grant_number": "80NSSC22K1398"
},
{
"grant_number": "80NSSC22K0583"
},
{
"grant_number": "GO2-23038X"
},
{
"grant_number": "46939-1-CCNS 22317F"
},
{
"grant_number": "2020747"
},
{
"grant_number": "80GSFC21M0002"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ad0228",
"primary_object": {
"basename": "OConnor_2023_ApJS_269_49.pdf",
"url": "https://authors.library.caltech.edu/records/0zbk7-kzt20/files/OConnor_2023_ApJS_269_49.pdf"
},
"pub_year": "2023",
"author_list": "O'Connor, B.; Kouveliotou, C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ejj37-frq33",
"eprint_status": "archive",
"datestamp": "2024-04-23 18:18:38",
"lastmod": "2026-03-27 18:21:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Podgorn\u00fd-Jakub",
"name": {
"family": "Podgorn\u00fd",
"given": "J."
},
"orcid": "0000-0001-5418-291X"
},
{
"name": {
"family": "Marra",
"given": "L."
}
},
{
"name": {
"family": "Muleri",
"given": "F."
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Rodriguez\u00a0Cavero",
"given": "N."
},
"orcid": "0000-0001-5256-0278"
},
{
"name": {
"family": "Ratheesh",
"given": "A."
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Dov\u010diak",
"given": "M."
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Miku\u0161incov\u00e1",
"given": "R."
},
"orcid": "0000-0001-7374-843X"
},
{
"name": {
"family": "Brigitte",
"given": "M."
}
},
{
"name": {
"family": "Steiner",
"given": "J. F."
}
},
{
"name": {
"family": "Veledina",
"given": "A."
},
"orcid": "0000-0002-5767-7253"
},
{
"name": {
"family": "Bianchi",
"given": "S."
}
},
{
"name": {
"family": "Krawczynski",
"given": "H."
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Svoboda",
"given": "J."
}
},
{
"name": {
"family": "Kaaret",
"given": "P."
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Matt",
"given": "G."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garcia",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Petrucci",
"given": "P.-O."
}
},
{
"name": {
"family": "Lutovinov",
"given": "A."
},
"orcid": "0000-0002-6255-9972"
},
{
"name": {
"family": "Semena",
"given": "A."
}
},
{
"name": {
"family": "Di\u00a0Marco",
"given": "A."
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Negro",
"given": "M."
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Weisskopf",
"given": "M. C."
}
},
{
"name": {
"family": "Ingram",
"given": "A."
},
"orcid": "0000-0002-5311-9078"
},
{
"name": {
"family": "Poutanen",
"given": "J."
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Beheshtipour",
"given": "B."
},
"orcid": "0000-0002-8524-1537"
},
{
"name": {
"family": "Chun",
"given": "S."
}
},
{
"name": {
"family": "Hu",
"given": "K."
}
},
{
"name": {
"family": "Mizuno",
"given": "T."
}
},
{
"name": {
"family": "Sixuan",
"given": "Z."
}
},
{
"name": {
"family": "Tombesi",
"given": "F."
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Zane",
"given": "S."
}
},
{
"name": {
"family": "Agudo",
"given": "I."
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "L. A."
}
},
{
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "L."
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "W. H."
}
},
{
"name": {
"family": "Bellazzini",
"given": "R."
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bongiorno",
"given": "S. D."
}
},
{
"name": {
"family": "Bonino",
"given": "R."
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "A."
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "N."
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "F."
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "S."
}
},
{
"name": {
"family": "Cavazzuti",
"given": "E."
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "C."
}
},
{
"name": {
"family": "Ciprini",
"given": "S."
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "E."
}
},
{
"name": {
"family": "De\u00a0Rosa",
"given": "A."
}
},
{
"name": {
"family": "Del\u00a0Monte",
"given": "E."
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di\u00a0Gesu",
"given": "L."
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di\u00a0Lalla",
"given": "N."
}
},
{
"name": {
"family": "Donnarumma",
"given": "I."
}
},
{
"name": {
"family": "Doroshenko",
"given": "V."
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Ehlert",
"given": "S. R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "T."
}
},
{
"name": {
"family": "Evangelista",
"given": "Y."
}
},
{
"name": {
"family": "Fabiani",
"given": "S."
}
},
{
"name": {
"family": "Ferrazzoli",
"given": "R."
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Gunji",
"given": "S."
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "K."
}
},
{
"name": {
"family": "Heyl",
"given": "J."
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "W."
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "S. G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "V."
}
},
{
"name": {
"family": "Kislat",
"given": "F."
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Kitaguchi",
"given": "T."
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "J. J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "La\u00a0Monaca",
"given": "F."
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "L."
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "I."
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "S."
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "A."
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "F."
}
},
{
"name": {
"family": "Marinucci",
"given": "A."
}
},
{
"name": {
"family": "Marscher",
"given": "A. P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "H. L."
}
},
{
"name": {
"family": "Massaro",
"given": "F."
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Mitsuishi",
"given": "I."
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
}
},
{
"name": {
"family": "O'Dell",
"given": "S. L."
}
},
{
"name": {
"family": "Omodei",
"given": "N."
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "C."
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "A."
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "G. G."
}
},
{
"name": {
"family": "Peirson",
"given": "A. L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "M."
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "M."
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "M."
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "A."
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "S."
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "B. D."
}
},
{
"name": {
"family": "Rankin",
"given": "J."
}
},
{
"name": {
"family": "Roberts",
"given": "O. J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "R. W."
}
},
{
"name": {
"family": "Sgr\u00f2",
"given": "C."
}
},
{
"name": {
"family": "Slane",
"given": "P."
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "P."
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "G."
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "D. A."
}
},
{
"name": {
"family": "Tamagawa",
"given": "T."
}
},
{
"name": {
"family": "Tavecchio",
"given": "F."
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "R."
}
},
{
"name": {
"family": "Tawara",
"given": "Y."
}
},
{
"name": {
"family": "Tennant",
"given": "A. F."
}
},
{
"name": {
"family": "Thomas",
"given": "N. E."
}
},
{
"name": {
"family": "Trois",
"given": "A."
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "S. S."
}
},
{
"name": {
"family": "Turolla",
"given": "R."
},
"orcid": "0000-0002-5825-8149"
},
{
"name": {
"family": "Vink",
"given": "J."
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Wu",
"given": "K."
}
},
{
"name": {
"family": "Xie",
"given": "F."
}
}
]
},
"title": "The first X-ray polarimetric observation of the black hole binary LMC\u00a0X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC).
\nThe authors thank the referee, Andrzej Zdziarski, for very detailed and useful comments. JPod, MD, JS, and VK thank for the support from the GACR project 21–06825X and the institutional support from RVO:67985815. AV acknowledges support from the Academy of Finland grants 347003 and 355672. HK and NRC acknowledge NASA support under grants 80NSSC18K0264, 80NSSC22K1291, 80NSSC21K1817, and NNX16AC42G. P-OP acknowledges financial support from the French High Energy Program (PNHE/CNRS) and from the French Space Agency (CNES). AI acknowledges support from the Royal Society.
\n\nThe IXPE data used in this paper are publicly available in the HEASARC data base (https://heasarc.gsfc.nasa.gov/docs/ixpe/archive/). The analysis and simulation software IXPEOBSSIM developed by IXPE collaboration and its documentation is available publicly through the webpage https://ixpeobssim.readthedocs.io/en/latest/?badge = latest.494. The NICER and NuSTAR data underlying this paper are publicly available from the NuSTAR (https://heasarc.gsfc.nasa.gov/docs/nustar/archive/nustar_archive.html) and NICER (https://heasarc.gsfc.nasa.gov/docs/nicer/nicer_archive.html) archives. The ART-XC data used in this paper publicly available at ftp://hea.iki.rssi.ru/public/SRG/ART-XC/data/LMC_X-1/lmc_x_1_barycen.fits.gz. The XSPEC software is publicly available in the HEASARC data base (https://heasarc.gsfc.nasa.gov/xanadu/xspec/). The corresponding XSPEC packages used for this work can be found in the references stated in this paper or shared on reasonable request.
",
"abstract": "We report on an X-ray polarimetric observation of the high-mass X-ray binary LMC X-1 in the high/soft state, obtained by the Imaging X-ray Polarimetry Explorer (IXPE) in 2022 October. The measured polarization is below the minimum detectable polarization of 1.1 per cent (at the 99 per cent confidence level). Simultaneously, the source was observed with the Neutron Star Interior Composition Explorer (NICER), Nuclear Spectroscopic Telescope Array (NuSTAR), and Spectrum-Rontgen-Gamma (SRG)/Astronomical Roentgen Telescope – X-ray Concentrator (ART-XC) instruments, which enabled spectral decomposition into a dominant thermal component and a Comptonized one. The low 2–8 keV polarization of the source did not allow for strong constraints on the black hole spin and inclination of the accretion disc. However, if the orbital inclination of about 36° is assumed, then the upper limit is consistent with predictions for pure thermal emission from geometrically thin and optically thick discs. Assuming the polarization degree of the Comptonization component to be 0, 4, or 10 per cent, and oriented perpendicular to the polarization of the disc emission (in turn assumed to be perpendicular to the large-scale ionization cone orientation detected in the optical band), an upper limit to the polarization of the disc emission of 1.0, 0.9, or 0.9 per cent, respectively, is found (at the 99 per cent confidence level).
",
"date": "2023-12",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "526",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "5964-5975",
"issn": "0035-8711",
"official_url": "https://authors.library.caltech.edu/records/ejj37-frq33",
"funders": {
"items": [
{
"grant_number": "NNM15AA18C"
},
{
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{},
{},
{
"grant_number": "21\u201306825X"
},
{
"grant_number": "RVO:67985815"
},
{
"grant_number": "347003"
},
{
"grant_number": "355672"
},
{
"grant_number": "80NSSC18K0264"
},
{
"grant_number": "80NSSC22K1291"
},
{
"grant_number": "80NSSC21K1817"
},
{
"grant_number": "NNX16AC42G"
},
{},
{},
{}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stad3103",
"primary_object": {
"basename": "stad3103.pdf",
"url": "https://authors.library.caltech.edu/records/ejj37-frq33/files/stad3103.pdf"
},
"pub_year": "2023",
"author_list": "Podgorn\u00fd, J.; Marra, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jzm3c-jn583",
"eprint_status": "archive",
"datestamp": "2024-02-26 22:25:28",
"lastmod": "2026-03-27 19:58:51",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zhou-Ping",
"name": {
"family": "Zhou",
"given": "Ping"
},
"orcid": "0000-0002-5683-822X"
},
{
"name": {
"family": "Prokhorov",
"given": "Dmitry"
},
"orcid": "0000-0001-6511-4330"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Yang",
"given": "Yi-Jung"
},
"orcid": "0000-0001-9108-573X"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Silvestri",
"given": "Stefano"
},
"orcid": "0000-0002-8665-0105"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Reynoso",
"given": "Estela"
},
"orcid": "0000-0002-1875-7701"
},
{
"name": {
"family": "Moffett",
"given": "David"
},
"orcid": "0000-0003-1821-4966"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Swartz",
"given": "Doug"
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "Kim",
"given": "Dawoon E."
},
"orcid": "0000-0001-5717-3736"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garcia",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
},
"orcid": "0000-0002-9901-233X"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver"
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Magnetic Structures and Turbulence in SN 1006 Revealed with Imaging X-Ray Polarimetry",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC). P.Z. acknowledges the support from NSFC grant No. 12273010 and Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) Veni Fellowship grant No. 639.041.647. C.-Y.N. and Y.J.Y. are supported by a GRF grant of the Hong Kong Government under HKU 17305419. N.B. was supported by the INAF MiniGrant \"PWNnumpol—Numerical Studies of Pulsar Wind Nebulae in the Light of IXPE.\"
\n\nixpeobssim (vers. 30.0; Baldini et al. 2022), DS9 (Joye & Mandel 2003; Smithsonian Astrophysical Observatory 2000), SAS (SAS Development Team 2014), Xspec (vers. 12.9.0u; Arnaud 1996)
",
"abstract": "\n
Young supernova remnants strongly modify the surrounding magnetic fields, which in turn play an essential role in accelerating cosmic rays (CRs). The X-ray polarization measurements probe magnetic field morphology and turbulence at the immediate acceleration site. We report the X-ray polarization distribution in the northeastern shell of SN 1006 from a 1 Ms observation with the Imaging X-ray Polarimetry Explorer. We found an average polarization degree of 22.4% ± 3.5% and an average polarization angle of −45.°4 ± 4.°5 (measured on the plane of the sky from north to east). The X-ray polarization angle distribution reveals that the magnetic fields immediately behind the shock in the northeastern shell of SN 1006 are nearly parallel to the shock normal or radially distributed, similar to that in the radio observations, and consistent with the quasi-parallel CR acceleration scenario. The X-ray emission is marginally more polarized than that in the radio band. The X-ray polarization degree of SN 1006 is much larger than that in Cas A and Tycho, together with the relatively tenuous and smooth ambient medium of the remnant, favoring that CR-induced instabilities set the magnetic turbulence in SN 1006, and CR acceleration is environment-dependent.
\n
© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the anonymous referee for the feedback, which improved the quality of the manuscript. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. This research has also made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This work is supported by NASA under grant No. 80NSSC22K0054.
",
"abstract": "We present the first joint NuSTAR and NICER observations of the ultracompact X-ray binary 4U 0614+091. This source shows quasiperiodic flux variations on the timescale of ∼days. We use reflection modeling techniques to study various components of the accretion system as the flux varies. We find that the flux of the reflected emission and the thermal components representing the disk and the compact object trend closely with the overall flux. However, the flux of the power-law component representing the illuminating X-ray corona scales in the opposite direction, increasing as the total flux decreases. During the lowest flux observation, we see evidence of accretion disk truncation from roughly 6 gravitational radii to 11.5 gravitational radii. This is potentially analogous to the truncation seen in black hole low-mass X-ray binaries, which tends to occur during the low/hard state at sufficiently low Eddington ratios.
",
"date": "2023-11-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "957",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "27",
"issn": "0004-637X",
"official_url": "https://authors.library.caltech.edu/records/nktc2-4d554",
"funders": {
"items": [
{
"grant_number": "80NSSC22K0054"
}
]
},
"local_group": {
"items": [
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
},
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acf4f3",
"primary_object": {
"basename": "Moutard_2023_ApJ_957_27.pdf",
"url": "https://authors.library.caltech.edu/records/nktc2-4d554/files/Moutard_2023_ApJ_957_27.pdf"
},
"pub_year": "2023",
"author_list": "Moutard, D. L.; Ludlam, R. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0qx4b-v9360",
"eprint_status": "archive",
"datestamp": "2023-08-22 21:24:00",
"lastmod": "2026-01-29 17:10:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Di-Gesu-Laura",
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Kim",
"given": "Dawoon E."
},
"orcid": "0000-0001-5717-3736"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Kiehlmann",
"given": "Sebastian"
},
"orcid": "0000-0001-6314-9177"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Middei",
"given": "Riccardo"
},
"orcid": "0000-0001-9815-9092"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pacciani",
"given": "Luigi"
},
"orcid": "0000-0001-6897-5996"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Blinov",
"given": "Dmitry"
},
"orcid": "0000-0003-0611-5784"
},
{
"name": {
"family": "Bourbah",
"given": "Ioakeim G."
},
"orcid": "0000-0002-8597-6154"
},
{
"name": {
"family": "Kontopodis",
"given": "Evangelos"
},
"orcid": "0009-0009-8043-0986"
},
{
"name": {
"family": "Mandarakas",
"given": "Nikos"
},
"orcid": "0000-0002-2567-2132"
},
{
"name": {
"family": "Romanopoulos",
"given": "Stylianos"
},
"orcid": "0000-0002-2897-2448"
},
{
"id": "Skalidis-Raphael",
"name": {
"family": "Skalidis",
"given": "Raphael"
},
"orcid": "0000-0003-2337-0277"
},
{
"name": {
"family": "Vervelaki",
"given": "Anna"
},
"orcid": "0000-0003-0271-9724"
},
{
"name": {
"family": "Casadio",
"given": "Carolina"
},
"orcid": "0000-0003-1117-2863"
},
{
"name": {
"family": "Escudero",
"given": "Juan"
},
"orcid": "0000-0002-4131-655X"
},
{
"name": {
"family": "Myserlis",
"given": "Ioannis"
},
"orcid": "0000-0003-3025-9497"
},
{
"name": {
"family": "Gurwell",
"given": "Mark A."
},
"orcid": "0000-0003-0685-3621"
},
{
"name": {
"family": "Rao",
"given": "Ramprasad"
},
"orcid": "0000-0002-1407-7944"
},
{
"name": {
"family": "Keating",
"given": "Garrett K."
},
"orcid": "0000-0002-3490-146X"
},
{
"name": {
"family": "Kouch",
"given": "Pouya M."
},
"orcid": "0000-0002-9328-2750"
},
{
"name": {
"family": "Lindfors",
"given": "Elina"
},
"orcid": "0000-0002-9155-6199"
},
{
"name": {
"family": "Aceituno",
"given": "Francisco Jos\u00e9"
},
"orcid": "0000-0001-8074-4760"
},
{
"name": {
"family": "Bernardos",
"given": "Maria I."
},
"orcid": "0000-0001-8872-1168"
},
{
"name": {
"family": "Bonnoli",
"given": "Giacomo"
},
"orcid": "0000-0003-2464-9077"
},
{
"name": {
"family": "Casanova",
"given": "V\u00edctor"
}
},
{
"name": {
"family": "Garc\u00eda-Comas",
"given": "Maya"
},
"orcid": "0000-0003-2323-4486"
},
{
"name": {
"family": "Ag\u00eds-Gonz\u00e1lez",
"given": "Beatriz"
},
"orcid": "0000-0001-7702-8931"
},
{
"name": {
"family": "Husillos",
"given": "C\u00e9sar"
},
"orcid": "0000-0001-8286-5443"
},
{
"name": {
"family": "Marchini",
"given": "Alessandro"
},
"orcid": "0000-0003-3779-6762"
},
{
"name": {
"family": "Sota",
"given": "Alfredo"
},
"orcid": "0000-0002-9404-6952"
},
{
"name": {
"family": "Imazawa",
"given": "Ryo"
},
"orcid": "0000-0002-0643-7946"
},
{
"name": {
"family": "Sasada",
"given": "Mahito"
},
"orcid": "0000-0001-5946-9960"
},
{
"name": {
"family": "Fukazawa",
"given": "Yasushi"
},
"orcid": "0000-0002-0921-8837"
},
{
"name": {
"family": "Kawabata",
"given": "Koji S."
},
"orcid": "0000-0001-6099-9539"
},
{
"name": {
"family": "Uemura",
"given": "Makoto"
},
"orcid": "0000-0002-7375-7405"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Nakaoka",
"given": "Tatsuya"
}
},
{
"name": {
"family": "Akitaya",
"given": "Hiroshi"
},
"orcid": "0000-0001-6156-238X"
},
{
"name": {
"family": "Savchenko",
"given": "Sergey S."
},
"orcid": "0000-0003-4147-3851"
},
{
"name": {
"family": "Vasilyev",
"given": "Andrey A."
},
"orcid": "0000-0002-8293-0214"
},
{
"name": {
"family": "G\u00f3mez",
"given": "Jos\u00e9 L."
},
"orcid": "0000-0003-4190-7613"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Barnouin",
"given": "Thibault"
},
"orcid": "0000-0003-1340-5675"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Costamante",
"given": "Luigi"
},
"orcid": "0000-0002-8120-5272"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Cibrario",
"given": "Nicol\u00f2"
},
"orcid": "0000-0003-3842-4493"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Di Pierro",
"given": "Federico"
},
"orcid": "0000-0003-4861-432X"
},
{
"name": {
"family": "Errando",
"given": "Manel"
},
"orcid": "0000-0002-1853-863X"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Lisalda",
"given": "Lindsey"
},
"orcid": "0000-0002-5202-1642"
},
{
"name": {
"family": "Madejski",
"given": "Grzegorz"
}
},
{
"name": {
"family": "Malacaria",
"given": "Christian"
},
"orcid": "0000-0002-0380-0041"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Paggi",
"given": "Alessandro"
},
"orcid": "0000-0002-5646-2410"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garcia",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Discovery of X-ray polarization angle rotation in the jet from blazar Mrk 421",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astronomy and Astrophysics",
"note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2023. \n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC), and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). The IAA-CSIC group acknowledges financial support from the grant CEX2021-001131-S funded by MCIN/AEI/10.13039/501100011033 to the Instituto de Astrof\u00edsica de Andaluc\u00eda-CSIC and through grant PID2019-107847RB-C44. The POLAMI observations were carried out at the IRAM 30\u2009m Telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). The Submillimetre Array is a joint project between the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics and is funded by the Smithsonian Institution and the Academia Sinica. Mauna Kea, the location of the SMA, is a culturally important site for the indigenous Hawaiian people; we are privileged to study the cosmos from its summit. Some of the data reported here are based on observations made with the Nordic Optical Telescope, owned in collaboration with the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku and the University of Oslo, representing Denmark, Finland and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. E.L. was supported by Academy of Finland projects 317636 and 320045. The data presented here were obtained (in part) with ALFOSC, which is provided by the Instituto de Astrofisica de Andalucia (IAA) under a joint agreement with the University of Copenhagen and NOT. We are grateful to V. Braga, M. Monelli and M. S\u00e4nchez Benavente for performing the observations at the Nordic Optical Telescope. Part of the French contributions is supported by the Scientific Research National Center (CNRS) and the French spatial agency (CNES). The research at Boston University was supported in part by National Science Foundation grant AST-2108622, NASA Fermi Guest Investigator grants 80NSSC21K1917 and 80NSSC22K1571, and NASA Swift Guest Investigator grant 80NSSC22K0537. This research was conducted in part using the Mimir instrument, jointly developed at Boston University and Lowell Observatory and supported by NASA, NSF and the W.M. Keck Foundation. We thank D. Clemens for guidance in the analysis of the Mimir data. This work was supported by JST, the establishment of university fellowships towards the creation of science and technology innovation, grant number JPMJFS2129. This work was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI grant number JP21H01137. This work was also partially supported by the Optical and Near-Infrared Astronomy Inter-University Cooperation Program from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. We are grateful to the observation and operating members of the Kanata Telescope. Some of the data are based on observations collected at the Observatorio de Sierra Nevada, owned and operated by the Instituto de Astrof\u00edsica de Andaluc\u00eda (IAA-CSIC). Further data are based on observations collected at the Centro Astron\u00f3mico Hispano en Andaluc\u00eda (CAHA), operated jointly by Junta de Andaluc\u00eda and Consejo Superior de Investigaciones Cient\u00edficas (IAA-CSIC). This research has made use of data from the RoboPol programme, a collaboration between Caltech, the University of Crete, IA-FORTH, IUCAA, the MPIfR and the Nicolaus Copernicus University, which was conducted at Skinakas Observatory in Crete, Greece. D.B., S.K., R.S. and N.M., acknowledge support from the European Research Council (ERC) under the European Unions Horizon 2020 Research and Innovation programme under grant agreement no. 771282. C.C. acknowledges support from the European Research Council (ERC) under the HORIZON ERC Grants 2021 programme under grant agreement no. 101040021. The research at Boston University was supported in part by National Science Foundation grant AST-2108622, NASA Fermi Guest Investigator grant 80NSSC21K1917 and 80NSSC22K1571, and NASA Swift Guest Investigator grant 80NSSC22K0537. This work was supported by NSF grant AST-2109127. We acknowledge the use of public data from the Swift data archive. Data from the Steward Observatory spectropolarimetric monitoring project were used. This programme is supported by Fermi Guest Investigator grants NNX08AW56G, NNX09AU10G, NNX12AO93G and NNX15AU81G. We acknowledge funding to support our NOT observations from the Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Finland (Academy of Finland grant no 306531). This work has made use of data from the Asteroid Terrestrial-impact Last Alert System (ATLAS) project. The Asteroid Terrestrial-impact Last Alert System (ATLAS) project is primarily funded to search for near-Earth asteroids through NASA grants NN12AR55G, 80NSSC18K0284 and 80NSSC18K1575; by-products of the NEO search include images and catalogues from the survey area. This work was partially funded by Kepler/K2 grant J1944/80NSSC19K0112 and HST GO-15889, and STFC grants ST/T000198/1 and ST/S006109/1. The ATLAS science products have been made possible through the contributions of the University of Hawaii Institute for Astronomy, the Queen's University Belfast, the Space Telescope Science Institute, the South African Astronomical Observatory and The Millennium Institute of Astrophysics (MAS), Chile. The Very Long Baseline Array is an instrument of the National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under a cooperative agreement by Associated Universities, Inc. \n\nContributions. L.D.G. performed the analysis and led the writing of the paper. H.L.M., S.R.E., D.E.K., F. Muleri and A.D.M. contributed to the IXPE data analysis. I.D., F. Tavecchio, R.W.R., A.P.M. and S.G.J. contributed to the discussion and other parts of the paper, and the latter two provided the VLBA images. I.L. coordinated the multiwavelength observations. I.L. and S.K. contributed the random walk simulations. I.A., C.C., J.E., M.A.G., I. Myserlis, R.R and G.K.K. contributed the radio observations. S.G.J. contributed the infrared observations. S.S.S. performed modelling of the host galaxy in the H band. B.A.-G., F.J.A., I.A., H.A., M.I.B., D.B., G.B., I.G.B., V.C., Y.F., M.G.-C., C.H., R.I., K.S.K., S.K., E.K., P.M.K., E.L., N.M., A. Marchini, T. Mizuno, T.N., S.R., M.S., R.S., A.S., M.U. and A.V. contributed the optical observations. A.A.V. contributed to the paper discussion. R.M., M.P. and S.P. contributed to the Swift data analysis. L.P. and M.N. contributed the Fermi data. The remaining authors are part of the IXPE team whose significant contribution made the X-ray polarization observations possible. \n\nData availability. The data that support the findings of this study are either publicly available at the HEASARC database or available from the corresponding author upon request. \n\nCode availability. The ixpeobssim software and documentation can be downloaded at https://github.com/lucabaldini/ixpeobssim. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41550_2023_2032_MOESM1_ESM.pdf
",
"abstract": "The magnetic-field conditions in astrophysical relativistic jets can be probed by multiwavelength polarimetry, which has been recently extended to X-rays. For example, one can track how the magnetic field changes in the flow of the radiating particles by observing rotations of the electric vector position angle \u03a8. Here we report the discovery of a \u03a8_X rotation in the X-ray band in the blazar Markarian\u2009421 at an average flux state. Across the 5\u2009days of Imaging X-ray Polarimetry Explorer observations on 4\u20136 and 7\u20139 June 2022, \u03a8_X rotated in total by \u2265360\u00b0. Over the two respective date ranges, we find constant, within uncertainties, rotation rates (80\u2009\u00b1\u20099\u00b0 per day and 91\u2009\u00b1\u20098\u00b0 per day) and polarization degrees (\u03a0_X =\u200910%\u2009\u00b1\u20091%). Simulations of a random walk of the polarization vector indicate that it is unlikely that such rotation(s) are produced by a stochastic process. The X-ray-emitting site does not completely overlap the radio, infrared and optical emission sites, as no similar rotation of \u03a8 was observed in quasi-simultaneous data at longer wavelengths. We propose that the observed rotation was caused by a helical magnetic structure in the jet, illuminated in the X-rays by a localized shock propagating along this helix. The optically emitting region probably lies in a sheath surrounding an inner spine where the X-ray radiation is released.",
"date": "2023-10",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "7",
"publisher": "Nature Publishing Group",
"pagerange": "1245-1258",
"issn": "2397-3366",
"official_url": "https://authors.library.caltech.edu/records/0qx4b-v9360",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Severo Ochoa Centre of Excellence",
"grant_number": "CEX2021-001131-S"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "MCIN/AEI/10.13039/501100011033"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "PID2019-107847RB-C44"
},
{
"agency": "Institut national des sciences de l'Univers (INSU)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Max Planck Society"
},
{
"agency": "Instituto Geogr\u00e1fico Nacional (IGN)"
},
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "Academia Sinica Institute of Astronomy and Astrophysics (ASIAA)"
},
{
"agency": "Academy of Finland",
"grant_number": "317636"
},
{
"agency": "Academy of Finland",
"grant_number": "320045"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "NSF",
"grant_number": "AST-2108622"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1917"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K1571"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0537"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "Japan Science and Technology Agency",
"grant_number": "JPMJFS2129"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP21H01137"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "771282"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101040021"
},
{
"agency": "NSF",
"grant_number": "AST-2109127"
},
{
"agency": "Fermi Guest Investigator grants",
"grant_number": "NNX08AW56G"
},
{
"agency": "NASA",
"grant_number": "NNX09AU10G"
},
{
"agency": "NASA",
"grant_number": "NNX12AO93G"
},
{
"agency": "NASA",
"grant_number": "NNX15AU81G"
},
{
"agency": "Academy of Finland",
"grant_number": "306531"
},
{
"agency": "NASA",
"grant_number": "NN12AR55G"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0284"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1575"
},
{
"agency": "NASA",
"grant_number": "J1944/80NSSC19K0112"
},
{
"agency": "NASA",
"grant_number": "HST GO-15889"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T000198/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/S006109/1"
}
]
},
"local_group": {
"items": [
{
"id": "Owens-Valley-Radio-Observatory"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41550-023-02032-7",
"primary_object": {
"basename": "41550_2023_2032_MOESM1_ESM.pdf",
"url": "https://authors.library.caltech.edu/records/0qx4b-v9360/files/41550_2023_2032_MOESM1_ESM.pdf"
},
"pub_year": "2023",
"author_list": "Di Gesu, Laura; Marshall, Herman L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/qs1n3-0t817",
"eprint_status": "archive",
"datestamp": "2024-07-11 16:17:59",
"lastmod": "2025-11-22 02:34:55",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Grefenstette-Brian-F",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Margutti-Raffaella",
"name": {
"family": "Margutti",
"given": "R."
},
"orcid": "0000-0003-4768-7586"
}
]
},
"title": "Early Hard X-Rays from the Nearby Core-collapse Supernova SN 2023ixf",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\nWe thank the anonymous referee for comments and helping to clarify the results in this Letter. This work makes use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.
\nB.G., M.B., H.E., and F.H. acknowledge support under NASA Contract No. NNG08FD60C. R.M. acknowledges support by the National Science Foundation under Award Nos. AST-2221789 and AST-2224255.
\n\nNuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift(XRT) - Swift Gamma-Ray Burst Mission
\n\nastropy (Astropy Collaboration et al. 2013, 2018,2022)
",
"abstract": "We present NuSTAR observations of the nearby SN 2023ixf in M101 (d = 6.9 Mpc) that provide the earliest hard X-ray detection of a nonrelativistic stellar explosion to date at δt ≈ 4 days and δt ≈ 11 days. The spectra are well described by a hot thermal bremsstrahlung continuum with T > 25 keV shining through a thick neutral medium with a neutral hydrogen column that decreases with time (initial NHint = 2.6 × 1023 cm−2). A prominent neutral Fe Kα emission line is clearly detected, similar to other strongly interacting supernovae (SNe) such as SN 2010jl. The rapidly decreasing intrinsic absorption with time suggests the presence of a dense but confined circumstellar medium (CSM). The absorbed broadband X-ray luminosity (0.3–79 keV) is LX ≈ 2.5 × 1040 erg s−1 during both epochs, with the increase in overall X-ray flux related to the decrease in the absorbing column. Interpreting these observations in the context of thermal bremsstrahlung radiation originating from the interaction of the SN shock with a dense medium we infer large particle densities in excess of nCSM ≈ 4 × 108 cm−3 at r < 1015 cm, corresponding to an enhanced progenitor mass-loss rate of \u1e40 ≈ 3 × 10\u207b\u2074 M\u2299 yr−1 for an assumed wind velocity of vw = 50 km s−1.
",
"date": "2023-07-20",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "952",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "L3",
"issn": "2041-8205",
"official_url": "https://authors.library.caltech.edu/records/qs1n3-0t817",
"funders": {
"items": [
{
"grant_number": "NNG08FD60C"
},
{
"grant_number": "AST-2221789"
},
{
"grant_number": "AST-2224255"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/2041-8213/acdf4e",
"primary_object": {
"basename": "Grefenstette_2023_ApJL_952_L3.pdf",
"url": "https://authors.library.caltech.edu/records/qs1n3-0t817/files/Grefenstette_2023_ApJL_952_L3.pdf"
},
"pub_year": "2023",
"author_list": "Grefenstette, Brian W.; Brightman, Murray; et al."
},
{
"id": "https://authors.library.caltech.edu/records/79w2q-rkc11",
"eprint_status": "archive",
"datestamp": "2024-07-11 16:33:54",
"lastmod": "2026-03-27 18:03:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Shivkumar-Hinna",
"name": {
"family": "Shivkumar",
"given": "Hinna"
},
"orcid": "0000-0001-9289-0570"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Balasubramanian-Arvind",
"name": {
"family": "Balasubramanian",
"given": "Arvind"
},
"orcid": "0000-0003-0477-7645"
},
{
"id": "Fremling-Christoffer",
"name": {
"family": "Fremling",
"given": "Christoffer"
},
"orcid": "0000-0002-4223-103X"
},
{
"id": "Corsi-Alessandra",
"name": {
"family": "Corsi",
"given": "Alessandra"
},
"orcid": "0000-0001-8104-3536"
},
{
"id": "Tzanidakis-Anastasios",
"name": {
"family": "Tzanidakis",
"given": "Anastasios"
},
"orcid": "0000-0003-0484-3331"
},
{
"id": "Nissanke-Samaya",
"name": {
"family": "Nissanke",
"given": "Samaya"
},
"orcid": "0000-0001-6573-7773"
},
{
"id": "Kasliwal-M-M",
"name": {
"family": "Kasliwal",
"given": "Mansi"
},
"orcid": "0000-0002-5619-4938"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Raaijmakers-Geert",
"name": {
"family": "Raaijmakers",
"given": "Geert"
},
"orcid": "0000-0002-9397-786X"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin Kruse"
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Carbone-Dario",
"name": {
"family": "Carbone",
"given": "Dario"
},
"orcid": "0000-0002-6575-4642"
},
{
"id": "A-J-Nayana",
"name": {
"family": "A. J.",
"given": "Nayana"
},
"orcid": "0000-0002-8070-5400"
},
{
"id": "D\u00e9sert-Jean-Michel",
"name": {
"family": "D\u00e9sert",
"given": "Jean-Michel"
},
"orcid": "0000-0002-0875-8401"
},
{
"id": "Andreoni-Igor",
"name": {
"family": "Andreoni",
"given": "Igor"
},
"orcid": "0000-0002-8977-1498"
}
]
},
"title": "SN2019wxt: An Ultrastripped Supernova Candidate Discovered in the Electromagnetic Follow-up of a Gravitational Wave Trigger",
"ispublished": "pub",
"full_text_status": "public",
"note": "© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
\n\n\n
J.M.D. and H.S. acknowledge support from the Amsterdam Academic Alliance (AAA) Program, and the European Research Council (ERC) European Union's Horizon 2020 research and innovation program (grant agreement No. 679633; Exo-Atmos). This work is part of the research program VIDI New Frontiers in Exoplanetary Climatology, with project number 614.001.601, which is (partly) financed by the Dutch Research Council (NWO). F.H. and A.J. would like to thank observational support from Chandra X-ray observatory staff. Their work was supported by Chandra observational grant award GO0-21067X. A.B. and A.C. acknowledge support from the National Science Foundation via grant No. 1907975. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under a cooperative agreement by Associated Universities, Inc. H.S. would like to thank Yuhan Yao for the methodologies developed to characterize USSNe that we have used in this work and for the insightful discussions throughout the course of this work. Nayana A.J. would like to acknowledge DST-INSPIRE Faculty Fellowship (IFA20- PH-259) for supporting this research.
\n
\n
We present optical, radio, and X-ray observations of a rapidly evolving transient SN2019wxt (PS19hgw), discovered during the search for an electromagnetic counterpart to the gravitational-wave (GW) trigger S191213g. Although S191213g was not confirmed as a significant GW event in the off-line analysis of LIGO-Virgo data, SN2019wxt remained an interesting transient due to its peculiar nature. The optical/near-infrared (NIR) light curve of SN2019wxt displayed a double-peaked structure evolving rapidly in a manner analogous to currently known ultrastripped supernovae (USSNe) candidates. This double-peaked structure suggests the presence of an extended envelope around the progenitor, best modeled with two components: (i) early-time shock-cooling emission and (ii) late-time radioactive 56Ni decay. We constrain the ejecta mass of SN2019wxt at Mej ≈ 0.20M\u2299, which indicates a significantly stripped progenitor that was possibly in a binary system. We also followed up SN2019wxt with long-term Chandra and Jansky Very Large Array observations spanning ∼260 days. We detected no definitive counterparts at the location of SN2019wxt in these long-term X-ray and radio observational campaigns. We establish the X-ray upper limit at 9.93 × 10−17 erg cm−2 s−1 and detect an excess radio emission from the region of SN2019wxt. However, there is little evidence for SN1993J- or GW170817-like variability of the radio flux over the course of our observations. A substantial host-galaxy contribution to the measured radio flux is likely. The discovery and early-time peak capture of SN2019wxt in optical/NIR observations during EMGW follow-up observations highlight the need for dedicated early, multiband photometric observations to identify USSNe.
\n
Published - Liu_2023_ApJ_951_145.pdf
",
"abstract": "We present a high-density relativistic reflection analysis of 21 spectra of six black hole X-ray binaries in the hard state with data from NuSTAR and Swift. We find that 76% of the observations in our sample require a disk density higher than the 10\u00b9\u2075 cm\u207b\u00b3 assumed in the previous reflection analysis. Compared with the measurements from active galactic nuclei, stellar mass black holes have higher disk densities. Our fits indicate that the inner disk radius is close to the innermost stable circular orbit in the luminous hard state. The coronal temperatures are significantly lower than the prediction of a purely thermal plasma, which can be explained with a hybrid plasma model. If the disk density is fixed at 10\u00b9\u2075 cm\u207b\u00b3, the disk ionization parameter is overestimated while the inner disk radius is unaffected.",
"date": "2023-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "951",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 145",
"id_number": "CaltechAUTHORS:20230725-746017000.23",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-746017000.23",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12250610185"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11973019"
},
{
"agency": "Natural Science Foundation of Shanghai",
"grant_number": "22ZR1403400"
},
{
"agency": "Shanghai Municipal Education Commission",
"grant_number": "2019-01-07-00-07-E00035"
},
{
"agency": "Fudan University",
"grant_number": "JIH1512604"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0586"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Isaac Newton Trust"
},
{
"agency": "St. Edmund's College, University of Cambridge"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acd8b9",
"primary_object": {
"basename": "Liu_2023_ApJ_951_145.pdf",
"url": "https://authors.library.caltech.edu/records/9s17r-hfe98/files/Liu_2023_ApJ_951_145.pdf"
},
"pub_year": "2023",
"author_list": "Liu, Honghui; Jiang, Jiachen; et al."
},
{
"id": "https://authors.library.caltech.edu/records/61ems-vbe67",
"eprint_id": 122089,
"eprint_status": "archive",
"datestamp": "2023-08-22 21:13:01",
"lastmod": "2026-02-03 22:29:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Marin-Fr\u00e9d\u00e9ric",
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Churazov",
"given": "Eugene"
},
"orcid": "0000-0002-0322-884X"
},
{
"name": {
"family": "Khabibullin",
"given": "Ildar"
},
"orcid": "0000-0003-3701-5882"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Barnouin",
"given": "Thibault"
},
"orcid": "0000-0003-1340-5675"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Middei",
"given": "Riccardo"
},
"orcid": "0000-0001-9815-9092"
},
{
"name": {
"family": "Vikhlinin",
"given": "Alexey"
}
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Sunyaev",
"given": "Rashid"
},
"orcid": "0000-0002-2764-7192"
},
{
"name": {
"family": "Forman",
"given": "William R."
},
"orcid": "0000-0002-9478-1682"
},
{
"name": {
"family": "Kraft",
"given": "Ralph"
},
"orcid": "0000-0002-0765-0511"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Doug"
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "X-ray polarization evidence for a 200-year-old flare of Sgr A*",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galaxies and clusters; High-energy astrophysics",
"note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2023. \n\nThe IXPE is a joint US and Italian mission. The US contribution is supported by NASA and led and managed by its Marshall Space Flight Center, with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by ASI through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica and the Istituto Nazionale di Fisica Nucleare in Italy. This research used data products provided by the IXPE team (the Marshall Space Flight Center, the Space Science Data Center, the Istituto Nazionale di Astrofisica and the Istituto Nazionale di Fisica Nucleare) and distributed with additional software tools by the HEASARC, at the NASA Goddard Space Flight Center. F.M. is grateful to the Astronomical Observatory of Strasbourg, the Centre National de la Recherche Scientifique and the University of Strasbourg under whose benevolence this paper was written. I.K. acknowledges support by the COMPLEX project from the European Research Council under the European Union's Horizon 2020 research and innovation programme grant agreement ERC-2019-AdG 882679. P.-O.P. acknowledges financial support from the French National Program of High Energy (PNHE)/Centre National de la Recherche Scientifique and from the French national space agency (Centre National d'Etudes Spatiales (CNES)). I.A. acknowledges financial support from the Spanish Ministerio de Ciencia e Innovaci\u00f3n (MCIN/AEI/ 10.13039/501100011033) through the Center of Excellence Severo Ochoa award for the Instituto de Astrof\u00edsica de Andaluc\u00eda-CSIC (CEX2021-001131-S), and through grants PID2019-107847RB-C44 and PID2022-139117NB-C44. A.I. acknowledges support from the Royal Society. A.V., W.F. and R.K. acknowledge support from NASA grant GO1-22136X, the Smithsonian Institution, and the Chandra High Resolution Camera Project through NASA contract NAS8-03060. C.-Y.N. is supported by a GRF grant of the Hong Kong Government under HKU 17305419. \n\nContributions. F.\u2009M. led the IXPE observation, contributed to the analysis and led the writing of the paper. E. C., I.K., R.F., L.D.G., T.B., A.D.M., R.M., E.\u2009C., P.\u2009S., F.\u2009M., R.S. and P.K. contributed to the IXPE analysis, discussion and writing of the paper. A.V., W.F. and R.K. provided and reduced the Chandra data used in this paper. S.B., I.D., P.-O.P. and T.E. contributed with discussion and parts of the paper. The remaining authors are part of the IXPE team whose substantial contribution made the satellite and the Galactic Centre observation possible. \n\nData availability. The IXPE data that support the findings of this study are freely available in the HEASARC IXPE data archive (https://heasarc.gsfc.nasa.gov/docs/ixpe/archive/). The XMM-Newton data can be found on the same website, and the Chandra data will be public after one year from the observation date. \n\nCode availability. The analysis and simulation software ixpeobssim developed by the IXPE collaboration and its documentation are available publicly through https://ixpeobssim.readthedocs.io/en/latest/?badge=latest.494. XSPEC is distributed and maintained under the aegis of the HEASARC and can be downloaded as part of HEAsoft from http://heasarc.gsfc.nasa.gov/docs/software/lheasoft/download.html. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41586_2023_6064_Fig5_ESM.jpg
Supplemental Material - 41586_2023_6064_Fig6_ESM.jpg
Supplemental Material - 41586_2023_6064_Tab1_ESM.jpg
Supplemental Material - 41586_2023_6064_Tab2_ESM.jpg
",
"abstract": "The centre of the Milky Way Galaxy hosts a black hole with a solar mass of about 4\u2009million (Sagittarius A* (Sgr A)) that is very quiescent at present with a luminosity many orders of magnitude below those of active galactic nuclei1. Reflection of X-rays from Sgr\u2009A* by dense gas in the Galactic Centre region offers a means to study its past flaring activity on timescales of hundreds and thousands of years2. The shape of the X-ray continuum and the strong fluorescent iron line observed from giant molecular clouds in the vicinity of Sgr\u2009A* are consistent with the reflection scenario3,4,5. If this interpretation is correct, the reflected continuum emission should be polarized6. Here we report observations of polarized X-ray emission in the direction of the molecular clouds in the Galactic Centre using the Imaging X-ray Polarimetry Explorer. We measure a polarization degree of 31%\u2009\u00b1\u200911%, and a polarization angle of \u221248\u00b0\u2009\u00b1\u200911\u00b0. The polarization angle is consistent with Sgr\u2009A* being the primary source of the emission, and the polarization degree implies that some 200 years ago, the X-ray luminosity of Sgr\u2009A* was briefly comparable to that of a Seyfert galaxy.",
"date": "2023-07-06",
"date_type": "published",
"publication": "Nature",
"volume": "619",
"number": "7968",
"publisher": "Nature Publishing Group",
"pagerange": "41-45",
"id_number": "CaltechAUTHORS:20230630-22232000.4",
"issn": "0028-0836",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230630-22232000.4",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "882679"
},
{
"agency": "Programme National Hautes Energies (PNHE)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "MCIN/AEI/10.13039/501100011033/"
},
{
"agency": "Severo Ochoa Centre of Excellence",
"grant_number": "CEX2021-001131-S"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "PID2019-107847RB-C44"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "PID2022-139117NB-C44"
},
{
"agency": "Royal Society"
},
{
"agency": "NASA",
"grant_number": "GO1-22136X"
},
{
"agency": "Smithsonian Institution"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "University of Hong Kong",
"grant_number": "HKU 17305419"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41586-023-06064-x",
"primary_object": {
"basename": "41586_2023_6064_Fig5_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/61ems-vbe67/files/41586_2023_6064_Fig5_ESM.jpg"
},
"related_objects": [
{
"basename": "41586_2023_6064_Fig6_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/61ems-vbe67/files/41586_2023_6064_Fig6_ESM.jpg"
},
{
"basename": "41586_2023_6064_Tab1_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/61ems-vbe67/files/41586_2023_6064_Tab1_ESM.jpg"
},
{
"basename": "41586_2023_6064_Tab2_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/61ems-vbe67/files/41586_2023_6064_Tab2_ESM.jpg"
}
],
"pub_year": "2023",
"author_list": "Marin, Fr\u00e9d\u00e9ric; Churazov, Eugene; et al."
},
{
"id": "https://authors.library.caltech.edu/records/pzn87-vvg25",
"eprint_id": 122313,
"eprint_status": "archive",
"datestamp": "2023-08-22 21:19:35",
"lastmod": "2025-11-22 02:35:52",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Hameury-Jean-Marie",
"name": {
"family": "Hameury",
"given": "Jean-Marie"
},
"orcid": "0000-0002-6412-0103"
},
{
"id": "Lasota-Jean-Pierre",
"name": {
"family": "Lasota",
"given": "Jean-Pierre"
},
"orcid": "0000-0002-6171-8396"
},
{
"id": "Baldi-Ranieri-D",
"name": {
"family": "Baldi",
"given": "Ranieri D."
},
"orcid": "0000-0002-1824-0411"
},
{
"id": "Bruni-Gabriele",
"name": {
"family": "Bruni",
"given": "Gabriele"
},
"orcid": "0000-0002-5182-6289"
},
{
"id": "Cann-Jenna-M",
"name": {
"family": "Cann",
"given": "Jenna M."
},
"orcid": "0000-0003-1051-6564"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah"
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Lazzarini-Margaret",
"name": {
"family": "Lazzarini",
"given": "Margaret"
},
"orcid": "0000-0003-3252-352X"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "Matthew J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Weaver-Kimberly-A",
"name": {
"family": "Weaver",
"given": "Kimberly A."
}
}
]
},
"title": "A New Sample of Transient Ultraluminous X-Ray Sources Serendipitously Discovered by Swift/XRT",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nWe wish to thank the Swift PI, Brad Cenko, for approving the target of opportunity requests we made to observe these transient sources, as well as the rest of the Swift team for carrying them out. We also acknowledge the use of public data from the Swift data archive. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. \n\nWe also wish to thank Patrick Slane, Director of the Chandra X-ray Center, for approving the DDT requests to observe Swift J130456.1-493158, Swift J095520.7+690401, and Swift J235749.9-323526, and the Chandra team for carrying out the observations. \n\nIn addition we wish to thank the NuSTAR PI, Fiona Harrison, for approving the DDT request we made to observe Swift J235749.9-323526 as well as the NuSTAR SOC for carrying out the observation. This work was also supported under NASA Contract No. NNG08FD60C. NuSTAR is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nThis research has made use of data obtained from the Chandra Source Catalog, provided by the Chandra X-ray Center (CXC) as part of the Chandra Data Archive. \n\nThis work was also based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. \n\nThis research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. \n\nBased on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESAC/ESA), and the Canadian Astronomy Data Centre (CADC/NRC/CSA). The Hubble Source Catalog can be accessed via doi:10.17909/T97P46, and the specific observations used can be accessed via doi:10.17909/jmva-dc49. \n\nThe National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. \n\nJ.M.C.'s research was supported by an appointment to the NASA Postdoctoral Program at the NASA Goddard Space Flight Center, administered by Oak Ridge Associated Universities under contract with NASA. M.H. acknowledges support from an ESO fellowship and J.-P.L. was supported in part by a grant from the French Space Agency CNES. \n\nFacilities: Swift (XRT - , UVOT) - , CXO - , NuSTAR - , XMM - , VLA - Very Large Array. \n\nSoftware: CIAO (Fruscione et al. 2006), XSPEC (Arnaud1996).\n\nPublished - Brightman_2023_ApJ_951_51.pdf
",
"abstract": "Ultraluminous X-ray sources (ULXs) are our best laboratories for studying extreme super-Eddington accretion. Most studies of these objects are of relatively persistent sources; however, there is growing evidence to suggest a large fraction of these sources are transient. Here we present a sample of five newly reported transient ULXs in the galaxies NGC 4945, NGC 7793, and M81 serendipitously discovered in Swift/XRT observations. Swift monitoring of these sources have provided well-sampled lightcurves, allowing for us to model the lightcurves with the disk-instability model of Hameury & Lasota, which implies durations of 60\u2013400 days and that the mass-accretion rate through the disk is close to or greater than the Eddington rate. Of the three source regions with prior Hubble Space Telescope imaging, color\u2013magnitude diagrams of the potential stellar counterparts show varying ages of the possible stellar counterparts. Our estimation of the rates of these sources in these three galaxies is 0.4\u20131.3 yr\u207b\u00b9. We find that, while persistent ULXs dominate the high end of galaxy luminosity functions, the number of systems that produce ULX luminosities are likely dominated by transient sources.",
"date": "2023-07-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "951",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 51",
"id_number": "CaltechAUTHORS:20230717-55375900.15",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230717-55375900.15",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acd18a",
"primary_object": {
"basename": "Brightman_2023_ApJ_951_51.pdf",
"url": "https://authors.library.caltech.edu/records/pzn87-vvg25/files/Brightman_2023_ApJ_951_51.pdf"
},
"pub_year": "2023",
"author_list": "Brightman, Murray; Hameury, Jean-Marie; et al."
},
{
"id": "https://authors.library.caltech.edu/records/yww8x-c9105",
"eprint_id": 122207,
"eprint_status": "archive",
"datestamp": "2023-08-22 21:18:29",
"lastmod": "2025-11-22 02:34:17",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Peltonen-Joshua",
"name": {
"family": "Peltonen",
"given": "Joshua"
},
"orcid": "0000-0002-5937-9778"
},
{
"id": "Rosolowsky-Erik",
"name": {
"family": "Rosolowsky",
"given": "Erik"
},
"orcid": "0000-0002-5204-2259"
},
{
"id": "Johnson-L-Clifton",
"name": {
"family": "Johnson",
"given": "L. Clifton"
}
},
{
"id": "Seth-Anil-C",
"name": {
"family": "Seth",
"given": "Anil C."
},
"orcid": "0000-0003-0248-5470"
},
{
"id": "Dalcanton-Julianne",
"name": {
"family": "Dalcanton",
"given": "Julianne"
},
"orcid": "0000-0002-1264-2006"
},
{
"id": "Bell-Eric-F",
"name": {
"family": "Bell",
"given": "Eric F."
},
"orcid": "0000-0002-5564-9873"
},
{
"id": "Braine-Jonathan",
"name": {
"family": "Braine",
"given": "Jonathan"
},
"orcid": "0000-0003-1740-1284"
},
{
"id": "Koch-Eric-W",
"name": {
"family": "Koch",
"given": "Eric W."
},
"orcid": "0000-0001-9605-780X"
},
{
"id": "Lazzarini-Margaret",
"name": {
"family": "Lazzarini",
"given": "Margaret"
},
"orcid": "0000-0003-3252-352X"
},
{
"id": "Leroy-Adam-K",
"name": {
"family": "Leroy",
"given": "Adam K."
},
"orcid": "0000-0002-2545-1700"
},
{
"id": "Skillman-Evan-D",
"name": {
"family": "Skillman",
"given": "Evan D."
},
"orcid": "0000-0003-0605-8732"
},
{
"id": "Smercina-Adam",
"name": {
"family": "Smercina",
"given": "Adam"
},
"orcid": "0000-0003-2599-7524"
},
{
"id": "Wainer-Tobin",
"name": {
"family": "Wainer",
"given": "Tobin"
},
"orcid": "0000-0001-6320-2230"
},
{
"id": "Williams-Benjamin-F",
"name": {
"family": "Williams",
"given": "Benjamin F."
},
"orcid": "0000-0002-7502-0597"
}
]
},
"title": "Clusters, clouds, and correlations: relating young clusters to giant molecular clouds in M33 and M31",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.\nThis article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model).\n\nWe thank the anonymous referees for providing comments that improved the quality of this paper. Support for this work was provided by NASA through grant no. GO-14610 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5\u201326555. JP and ER acknowledge the support of the Natural Sciences and Engineering Research Council Canada (NSERC), funding reference number RGPIN-2022-03499. EWK acknowledges support from the Smithsonian Institution as a Submillimeter Array (SMA) Fellow and the Natural Sciences and Engineering Research Council of Canada. LCJ acknowledges support through a CIERA Post-doctoral Fellowship at Northwestern University. AKL gratefully acknowledges support by grants 1653300 and 2205628 from the National Science Foundation and by a Humboldt Research Award from the Alexander von Humboldt Foundation. ML is supported by an NSF Astronomy and Astrophysics Post-doctoral Fellowship under award AST-2102721. AS is supported by NASA through grant #GO-14610 from the Space Telescope Science Institute.\n\nThis research made use of NASA's Astrophysics Data System (ADS) bibliographic services.\n\nALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.\n\nWe are grateful for the contributions from the open source software community. This paper made extensive use of software in the ASTROPY (Astropy Collaboration et al. 2013), NUMPY (van der Walt, Colbert & Varoquaux 2011), and MATPLOTLIB packages (Hunter 2007).\n\nData Availability:\nThis paper makes use of the following ALMA data: ADS/JAO.ALMA#2017.1.00901.S and 2019.1.01182.S. These data are available through the ALMA archive.\n\nSome of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST) http://dx.doi.org/10.17909/t9-ksyp-na40. All other analysis data are available from the authors upon receiving a reasonable request.\n\nPublished - stad1430.pdf
",
"abstract": "We use young clusters and giant molecular clouds (GMCs) in the galaxies M33 and M31 to constrain temporal and spatial scales in the star formation process. In M33, we compare the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER) catalogue of 1214 clusters with ages measured via colour\u2013magnitude diagram (CMD) fitting to 444 GMCs identified from a new 35 pc resolution Atacama Large Millimeter/submillimeter Array (ALMA) \u00b9\u00b2CO(2\u20131) survey. In M31, we compare the Panchromatic Hubble Andromeda Treasury (PHAT) catalogue of 1249 clusters to 251 GMCs measured from a Combined Array for Research in Millimeter-wave Astronomy (CARMA) \u00b9\u00b2CO(1\u20130) survey with 20 pc resolution. Through two-point correlation analysis, we find that young clusters have a high probability of being near other young clusters, but correlation between GMCs is suppressed by the cloud identification algorithm. By comparing the positions, we find that younger clusters are closer to GMCs than older clusters. Through cross-correlation analysis of the M33 cluster data, we find that clusters are statistically associated when they are \u226410 Myr old. Utilizing the high precision ages of the clusters, we find that clusters older than \u224818 Myr are uncorrelated with the molecular interstellar medium (ISM). Using the spatial coincidence of the youngest clusters and GMCs in M33, we estimate that clusters spend \u22484\u20136 Myr inside their parent GMC. Through similar analysis, we find that the GMCs in M33 have a total lifetime of \u224811\u201315 Myr. We also develop a drift model and show that the above correlations can be explained if the clusters in M33 have a 5\u201310 km s\u207b\u00b9 velocity dispersion relative to the molecular ISM.",
"date": "2023-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "522",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "6137-6149",
"id_number": "CaltechAUTHORS:20230710-599244800.20",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230710-599244800.20",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "HST-GO-14610"
},
{
"agency": "NASA",
"grant_number": "NAS 5-26555"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)",
"grant_number": "RGPIN-2022-03499"
},
{
"agency": "Smithsonian Institution"
},
{
"agency": "Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)"
},
{
"agency": "NSF",
"grant_number": "AST-1653300"
},
{
"agency": "NSF",
"grant_number": "AST-2205628"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NSF Astronomy and Astrophysics Fellowship",
"grant_number": "AST-2102721"
},
{
"agency": "ALMA partnership"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stad1430",
"primary_object": {
"basename": "stad1430.pdf",
"url": "https://authors.library.caltech.edu/records/yww8x-c9105/files/stad1430.pdf"
},
"pub_year": "2023",
"author_list": "Peltonen, Joshua; Rosolowsky, Erik; et al."
},
{
"id": "https://authors.library.caltech.edu/records/snkgv-rnb11",
"eprint_id": 122341,
"eprint_status": "archive",
"datestamp": "2023-08-22 21:11:24",
"lastmod": "2025-11-22 02:24:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Opher-Merav",
"name": {
"family": "Opher",
"given": "Merav"
},
"orcid": "0000-0002-8767-8273"
},
{
"name": {
"family": "Richardson",
"given": "John"
},
"orcid": "0000-0003-4041-7540"
},
{
"name": {
"family": "Zank",
"given": "Gary"
},
"orcid": "0000-0002-4642-6192"
},
{
"name": {
"family": "Florinski",
"given": "Vladimir"
},
"orcid": "0000-0001-5485-2872"
},
{
"name": {
"family": "Giacalone",
"given": "Joe"
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Sok\u00f3\u0142",
"given": "Justyna M."
},
"orcid": "0000-0002-4173-3601"
},
{
"name": {
"family": "Toth",
"given": "Gabor"
}
},
{
"name": {
"family": "Buxner",
"given": "Sanlyn"
},
"orcid": "0000-0002-8504-252X"
},
{
"name": {
"family": "Kornbleuth",
"given": "Marc"
},
"orcid": "0000-0002-3479-1766"
},
{
"name": {
"family": "Gkioulidou",
"given": "Matina"
},
"orcid": "0000-0001-9979-2164"
},
{
"name": {
"family": "Nikoukar",
"given": "Romina"
},
"orcid": "0000-0002-8608-2822"
},
{
"name": {
"family": "Van der Holst",
"given": "Bart"
},
"orcid": "0000-0001-5260-3944"
},
{
"name": {
"family": "Turner",
"given": "Drew"
},
"orcid": "0000-0002-2425-7818"
},
{
"name": {
"family": "Gross",
"given": "Nicholas"
},
"orcid": "0000-0002-4826-6575"
},
{
"name": {
"family": "Drake",
"given": "James"
},
"orcid": "0000-0002-9150-1841"
},
{
"name": {
"family": "Swisdak",
"given": "Marc"
},
"orcid": "0000-0002-5435-3544"
},
{
"name": {
"family": "Dialynas",
"given": "Kostas"
}
},
{
"name": {
"family": "Dayeh",
"given": "Maher"
},
"orcid": "0000-0001-9323-1200"
},
{
"name": {
"family": "Chen",
"given": "Yuxi"
},
"orcid": "0000-0001-7288-2805"
},
{
"name": {
"family": "Zieger",
"given": "Bertalan"
},
"orcid": "0000-0003-2761-5200"
},
{
"name": {
"family": "Powell",
"given": "Erick"
}
},
{
"name": {
"family": "Onubogu",
"given": "Chika"
}
},
{
"name": {
"family": "Ma",
"given": "Xiaohan"
}
},
{
"name": {
"family": "Bair",
"given": "Ethan"
}
},
{
"name": {
"family": "Elliott",
"given": "Heather"
},
"orcid": "0000-0003-2297-3922"
},
{
"name": {
"family": "Galli",
"given": "Andre"
},
"orcid": "0000-0003-2425-3793"
},
{
"name": {
"family": "Zhao",
"given": "Lingling"
}
},
{
"name": {
"family": "Adhikari",
"given": "Laxman"
},
"orcid": "0000-0003-1549-5256"
},
{
"name": {
"family": "Nakanotani",
"given": "Masaru"
},
"orcid": "0000-0002-7203-0730"
},
{
"name": {
"family": "Hill",
"given": "Matthew E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Mostafavi",
"given": "Parisa"
},
"orcid": "0000-0002-3808-3580"
},
{
"name": {
"family": "Du",
"given": "Senbei"
},
"orcid": "0000-0003-1134-3909"
},
{
"name": {
"family": "Guo",
"given": "Fan"
},
"orcid": "0000-0003-4315-3755"
},
{
"name": {
"family": "Reisenfeld",
"given": "Daniel"
},
"orcid": "0000-0003-1874-9450"
},
{
"name": {
"family": "Fuselier",
"given": "Stephen"
},
"orcid": "0000-0003-4101-7901"
},
{
"name": {
"family": "Izmodenov",
"given": "Vladislav"
},
"orcid": "0000-0002-1748-0982"
},
{
"name": {
"family": "Baliukin",
"given": "Igor"
},
"orcid": "0000-0002-8004-0904"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "Alan"
},
"orcid": "0000-0002-3840-7696"
},
{
"name": {
"family": "Miller",
"given": "Jesse"
}
},
{
"name": {
"family": "Wang",
"given": "Bingbing"
}
},
{
"name": {
"family": "Ghanbari",
"given": "Keyvan"
},
"orcid": "0000-0003-3595-7868"
},
{
"name": {
"family": "Kota",
"given": "Jozsef"
},
"orcid": "0000-0002-3715-0358"
},
{
"name": {
"family": "Loeb",
"given": "Abraham"
},
"orcid": "0000-0003-4330-287X"
},
{
"name": {
"family": "Burgess",
"given": "Juditra"
}
},
{
"name": {
"family": "Hokanson",
"given": "Sarah Chobot"
},
"orcid": "0000-0002-7348-4312"
},
{
"name": {
"family": "Morrow",
"given": "Cherilyn"
}
},
{
"name": {
"family": "Hong",
"given": "Adam"
}
},
{
"name": {
"family": "Boldon",
"given": "Andrea"
}
}
]
},
"title": "Solar wind with Hydrogen Ion charge Exchange and Large-Scale Dynamics (SHIELD) DRIVE Science Center",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astronomy and Astrophysics",
"note": "\u00a9 2023 Opher, Richardson, Zank, Florinski, Giacalone, Sok\u00f3\u0142, Toth, Buxner, Kornbleuth, Gkioulidou, Nikoukar, Van der Holst, Turner, Gross, Drake, Swisdak, Dialynas, Dayeh, Chen, Zieger, Powell, Onubogu, Ma, Bair, Elliott, Galli, Zhao, Adhikari, Nakanotani, Hill, Mostafavi, Du, Guo, Reisenfeld, Fuselier, Izmodenov, Baliukin, Cummings, Miller, Wang, Ghanbari, Kota, Loeb, Burgess, Hokanson, Morrow, Hong and Boldon. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. \n\nThis work is supported by NASA grant 18-DRIVE18_2-0029 as part of the NASA/DRIVE program titled \"Our Heliospheric Shield\", 80NSSC22M0164, https://shielddrivecenter.com. Some of the figures were produced by AH, Graphic Designer, adamhong.com. \n\nAuthor contributions: All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication. \n\nThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\n\nPublished - fspas-10-1143909.pdf
",
"abstract": "Most stars generate winds and move through the interstellar medium that surrounds them. This movement creates a cocoon formed by the deflection of these winds that envelops and protects the stars. We call these \"cocoons\" astrospheres. The Sun has its own cocoon, the heliosphere. The heliosphere is an immense shield that protects the Solar System from harsh, galactic radiation. The radiation that enters the heliosphere affects life on Earth as well as human space exploration. Galactic cosmic rays are the dominant source of radiation and principal hazard affecting space missions within our Solar System. Current global heliosphere models do not successfully predict the radiation environment at all locations or under different solar conditions. To understand the heliosphere's shielding properties, we need to understand its structure and large-scale dynamics. A fortunate confluence of missions has provided the scientific community with a treasury of heliospheric data. However, fundamental features remain unknown. The vision of the Solar wind with Hydrogen Ion charge Exchange and Large-Scale Dynamics (SHIELD) DRIVE Science Center is to understand the nature and structure of the heliosphere. Through four integrated research thrusts leading to the global model, SHIELD will: 1) determine the global nature of the heliosphere; 2) determine how pickup ions evolve from \"cradle to grave\" and affect heliospheric processes; 3) establish how the heliosphere interacts with and influences the Local Interstellar Medium (LISM); and 4) establish how cosmic rays are filtered by and transported through the heliosphere. The key deliverable is a comprehensive, self-consistent, global model of the heliosphere that explains data from all relevant in situ and remote observations and predicts the radiation environment. SHIELD will develop a \"digital twin\" of the heliosphere capable of: (a) predicting how changing solar and LISM conditions affect life on Earth, (b) understanding the radiation environment to support long-duration space travel, and (c) contributing toward finding life elsewhere in the Galaxy. SHIELD also will train the next-generation of heliophysicists, a diverse community fluent in team science and skilled working in highly transdisciplinary collaborative environments.",
"date": "2023-06-15",
"date_type": "published",
"publication": "Frontiers in Astronomy and Space Sciences",
"volume": "10",
"publisher": "Frontiers Media SA",
"pagerange": "Art. No. 1143909",
"id_number": "CaltechAUTHORS:20230717-55915200.38",
"issn": "2296-987X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230717-55915200.38",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "18-DRIVE18_2-0029"
},
{
"agency": "NASA",
"grant_number": "80NSSC22M0164"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3389/fspas.2023.1143909",
"primary_object": {
"basename": "fspas-10-1143909.pdf",
"url": "https://authors.library.caltech.edu/records/snkgv-rnb11/files/fspas-10-1143909.pdf"
},
"pub_year": "2023",
"author_list": "Opher, Merav; Richardson, John; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kspbf-btw64",
"eprint_id": 122070,
"eprint_status": "archive",
"datestamp": "2023-08-22 21:06:49",
"lastmod": "2026-03-27 18:45:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Drake-James-F",
"name": {
"family": "Drake",
"given": "J. F."
},
"orcid": "0000-0002-9150-1841"
},
{
"id": "McManus-Michael-D",
"name": {
"family": "McManus",
"given": "M. D."
},
"orcid": "0000-0001-6077-4145"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Badman-Samuel-T",
"name": {
"family": "Badman",
"given": "S. T."
},
"orcid": "0000-0002-6145-436X"
},
{
"id": "Larson-Davin-E",
"name": {
"family": "Larson",
"given": "D. E."
},
"orcid": "0000-0001-5030-6030"
},
{
"id": "Swisdak-Michael",
"name": {
"family": "Swisdak",
"given": "M."
},
"orcid": "0000-0002-5435-3544"
},
{
"id": "Horbury-Timothy-S",
"name": {
"family": "Horbury",
"given": "T. S."
},
"orcid": "0000-0002-7572-4690"
},
{
"id": "Raouafi-Nour-E",
"name": {
"family": "Raouafi",
"given": "N. E."
},
"orcid": "0000-0003-2409-3742"
},
{
"id": "Phan-Tai-D",
"name": {
"family": "Phan",
"given": "T."
},
"orcid": "0000-0002-6924-9408"
},
{
"id": "Velli-Marco",
"name": {
"family": "Velli",
"given": "M."
},
"orcid": "0000-0002-2381-3106"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Panasenco-Olga",
"name": {
"family": "Panasenco",
"given": "O."
},
"orcid": "0000-0002-4440-7166"
},
{
"id": "Kasper-Justin-C",
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
}
]
},
"title": "Interchange reconnection as the source of the fast solar wind within coronal holes",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Multidisciplinary",
"note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nThe FIELDS, SWEAP and ISOIS suites were designed, developed and are operated under NASA contract NNN06AA01C. We acknowledge the extraordinary contributions of the PSP mission operations and spacecraft engineering team at the Johns Hopkins University Applied Physics Laboratory. M.V. was supported in part by the International Space Science Institute, Bern, through the J. Geiss fellowship. J.F.D. and M.S. were supported by the NASA Drive Science Center on Solar Flare Energy Release (SolFER) under Grant 80NSSC20K0627, NASA Grant 80NSSC22K0433 and NSF Grant PHY2109083. T.S.H. is supported by STFC grant ST/W001071/1. O.P. was supported by the NASA Grant 80NSSC20K1829. Elements of this work benefited from discussions at the meeting of Team 463 at the International Space Science Institute (ISSI). \n\nContributions. S.D.B. and J.F.D. wrote the manuscript with major contributions from S.T.B. S.D.B. analysed the PSP measurements, with contributions from M.D.M., M.I.D., T.S.H. and D.E.L. S.T.B. performed the PFSS analysis. J.F.D. and M.S. performed the computer simulations. S.D.B., J.C.K. and D.J.M. lead the PSP/FIELDS, SWEAP and ISOIS teams, respectively. All authors participated in the data interpretation and read and commented on the manuscript. \n\nData availability. The PSP mission data used in this study are openly available at the NASA Space Physics Data Facility (https://nssdc.gsfc.nasa.gov) and were analysed using the IDL/SPEDAS software package (https://spedas.org/blog/). The computer simulations used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under contract no. DE-AC02- 05CH11231. Simulation data is available at https://doi.org/10.5281/zenodo.7562035. \n\nThe authors declare no competing interests.\n\nPublished - s41586-023-05955-3.pdf
Supplemental Material - 41586_2023_5955_Fig5_ESM.jpg
Supplemental Material - 41586_2023_5955_Fig6_ESM.jpg
",
"abstract": "The fast solar wind that fills the heliosphere originates from deep within regions of open magnetic field on the Sun called 'coronal holes'. The energy source responsible for accelerating the plasma is widely debated; however, there is evidence that it is ultimately magnetic in nature, with candidate mechanisms including wave heating and interchange reconnection. The coronal magnetic field near the solar surface is structured on scales associated with 'supergranulation' convection cells, whereby descending flows create intense fields. The energy density in these 'network' magnetic field bundles is a candidate energy source for the wind. Here we report measurements of fast solar wind streams from the Parker Solar Probe (PSP) spacecraft6 that provide strong evidence for the interchange reconnection mechanism. We show that the supergranulation structure at the coronal base remains imprinted in the near-Sun solar wind, resulting in asymmetric patches of magnetic 'switchbacks'7,8 and bursty wind streams with power-law-like energetic ion spectra to beyond 100\u2009keV. Computer simulations of interchange reconnection support key features of the observations, including the ion spectra. Important characteristics of interchange reconnection in the low corona are inferred from the data, including that the reconnection is collisionless and that the energy release rate is sufficient to power the fast wind. In this scenario, magnetic reconnection is continuous and the wind is driven by both the resulting plasma pressure and the radial Alfv\u00e9nic flow bursts.",
"date": "2023-06-06",
"date_type": "published",
"publication": "Nature",
"volume": "618",
"number": "7964",
"publisher": "Nature Publishing Group",
"pagerange": "252-256",
"id_number": "CaltechAUTHORS:20230630-524899000.3",
"issn": "0028-0836",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230630-524899000.3",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "International Space Science Institute (ISSI)"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0627"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0433"
},
{
"agency": "NSF",
"grant_number": "PHY-2109083"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/W001071/1"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1829"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC02-05CH11231"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41586-023-05955-3",
"pmcid": "PMC10247371",
"primary_object": {
"basename": "41586_2023_5955_Fig5_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/kspbf-btw64/files/41586_2023_5955_Fig5_ESM.jpg"
},
"related_objects": [
{
"basename": "41586_2023_5955_Fig6_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/kspbf-btw64/files/41586_2023_5955_Fig6_ESM.jpg"
},
{
"basename": "s41586-023-05955-3.pdf",
"url": "https://authors.library.caltech.edu/records/kspbf-btw64/files/s41586-023-05955-3.pdf"
}
],
"pub_year": "2023",
"author_list": "Bale, S. D.; Drake, J. F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/426w2-6p371",
"eprint_id": 121689,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:59:24",
"lastmod": "2025-11-22 02:29:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zhang-Zuobin",
"name": {
"family": "Zhang",
"given": "Zuobin"
},
"orcid": "0000-0003-0847-1299"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Liu-Honghui",
"name": {
"family": "Liu",
"given": "Honghui"
},
"orcid": "0000-0003-2845-1009"
},
{
"id": "Bambi-Cosimo",
"name": {
"family": "Bambi",
"given": "Cosimo"
},
"orcid": "0000-0002-3180-9502"
},
{
"id": "Reynolds-Christopher-S",
"name": {
"family": "Reynolds",
"given": "Christopher S."
},
"orcid": "0000-0002-1510-4860"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Young-Andrew-J",
"name": {
"family": "Young",
"given": "Andrew J."
},
"orcid": "0000-0003-3626-9151"
},
{
"id": "Gallo-Luigi-C",
"name": {
"family": "Gallo",
"given": "Luigi C."
}
},
{
"id": "Yu-Zhibo",
"name": {
"family": "Yu",
"given": "Zhibo"
}
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
}
]
},
"title": "The Low-temperature Corona in ESO 511-G030 Revealed by NuSTAR and XMM-Newton",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThis work was supported by the National Natural Science Foundation of China (NSFC), grant No. 11973019; the Natural Science Foundation of Shanghai, grant No. 22ZR1403400; the Shanghai Municipal Education Commission, grant No. 2019-01-07-00-07-E00035; and Fudan University, grant No. JIH1512604. J.J. acknowledges support from the Leverhulme Trust, the Isaac Newton Trust, and St Edmund's College, University of Cambridge.\n\nPublished - Zhang_2023_ApJ_949_4.pdf
",
"abstract": "We present the results from a coordinated XMM-Newton + NuSTAR observation of the Seyfert 1 galaxy ESO 511\u2212G030. With this joint monitoring program, we conduct a detailed variability and spectral analysis. The source remained in a low flux and very stable state throughout the observation period, although there are slight fluctuations of flux over long timescales. The broadband (0.3\u201378 keV) spectrum shows the presence of a power-law continuum with a soft excess below 2 keV, a relatively narrow iron K\u03b1 emission (\u223c6.4 keV), and an obvious cutoff at high energies. We find that the soft excess can be modeled by two different possible scenarios: a warm (kT\u2091 \u223c 0.19 keV) and optically thick (\u03c4 = 18\u201325) Comptonizing corona or a relativistic reflection from a high-density (log[n\u2091_/cm}\u207b\u00b3] = 17.1-18.5) inner disk. All models require a low temperature (kT\u2091 \u223c 13 keV) for the hot corona.",
"date": "2023-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "949",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 4",
"id_number": "CaltechAUTHORS:20230602-251659000.31",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230602-251659000.31",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11973019"
},
{
"agency": "Natural Science Foundation of Shanghai",
"grant_number": "22ZR1403400"
},
{
"agency": "Shanghai Municipal Education Commission",
"grant_number": "2019-01-07-00-07-E00035"
},
{
"agency": "Fudan University",
"grant_number": "JIH1512604"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Isaac Newton Trust"
},
{
"agency": "St. Edmund's College, University of Cambridge"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/acc38f",
"primary_object": {
"basename": "Zhang_2023_ApJ_949_4.pdf",
"url": "https://authors.library.caltech.edu/records/426w2-6p371/files/Zhang_2023_ApJ_949_4.pdf"
},
"pub_year": "2023",
"author_list": "Zhang, Zuobin; Jiang, Jiachen; et al."
},
{
"id": "https://authors.library.caltech.edu/records/j821t-5ac74",
"eprint_id": 121737,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:59:28",
"lastmod": "2025-11-22 02:25:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zhang-Zuobin",
"name": {
"family": "Zhang",
"given": "Zuobin"
},
"orcid": "0000-0003-0847-1299"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Liu-Honghui",
"name": {
"family": "Liu",
"given": "Honghui"
},
"orcid": "0000-0003-2845-1009"
},
{
"id": "Bambi-Cosimo",
"name": {
"family": "Bambi",
"given": "Cosimo"
},
"orcid": "0000-0002-3180-9502"
},
{
"id": "Reynolds-Christopher-S",
"name": {
"family": "Reynolds",
"given": "Christopher S."
},
"orcid": "0000-0002-1510-4860"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Madsen-Kristin",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Young-Andrew-J",
"name": {
"family": "Young",
"given": "Andrew"
},
"orcid": "0000-0003-3626-9151"
},
{
"id": "Gallo-Luigi-C",
"name": {
"family": "Gallo",
"given": "Luigi"
}
},
{
"id": "Yu-Zhibo",
"name": {
"family": "Yu",
"given": "Zhibo"
},
"orcid": "0000-0002-6990-9058"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John"
},
"orcid": "0000-0001-5506-9855"
}
]
},
"title": "The Low-temperature Corona in ESO 511\u2212G030 Revealed by NuSTAR and XMM-Newton",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThis work was supported by the National Natural Science Foundation of China (NSFC), grant No. 11973019; the Natural Science Foundation of Shanghai, grant No. 22ZR1403400; the Shanghai Municipal Education Commission, grant No. 2019-01-07-00-07-E00035; and Fudan University, grant No. JIH1512604. J.J. acknowledges support from the Leverhulme Trust, the Isaac Newton Trust, and St Edmund's College, University of Cambridge.\n\nPublished - Zhang_2023_ApJ_949_4.pdf
",
"abstract": "We present the results from a coordinated XMM-Newton + NuSTAR observation of the Seyfert 1 galaxy ESO 511\u2212G030. With this joint monitoring program, we conduct a detailed variability and spectral analysis. The source remained in a low flux and very stable state throughout the observation period, although there are slight fluctuations of flux over long timescales. The broadband (0.3\u201378 keV) spectrum shows the presence of a power-law continuum with a soft excess below 2 keV, a relatively narrow iron K\u03b1 emission (\u223c6.4 keV), and an obvious cutoff at high energies. We find that the soft excess can be modeled by two different possible scenarios: a warm (kT\u2091_e \u223c 0.19 keV) and optically thick (\u03c4 = 18\u201325) Comptonizing corona or a relativistic reflection from a high-density (log[n\u2091/cm\u207b\u00b3] = 17.1 \u2013 18.5) inner disk. All models require a low temperature (kT_e \u223c 13 keV) for the hot corona.",
"date": "2023-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "949",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 4",
"id_number": "CaltechAUTHORS:20230605-335206000.36",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230605-335206000.36",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11973019"
},
{
"agency": "Natural Science Foundation of Shanghai",
"grant_number": "22ZR1403400"
},
{
"agency": "Shanghai Municipal Education Commission",
"grant_number": "2019-01-07-00-07-E00035"
},
{
"agency": "Fudan University",
"grant_number": "JIH1512604"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Isaac Newton Trust"
},
{
"agency": "St. Edmund's College, University of Cambridge"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acc38f",
"primary_object": {
"basename": "Zhang_2023_ApJ_949_4.pdf",
"url": "https://authors.library.caltech.edu/records/j821t-5ac74/files/Zhang_2023_ApJ_949_4.pdf"
},
"pub_year": "2023",
"author_list": "Zhang, Zuobin; Jiang, Jiachen; et al."
},
{
"id": "https://authors.library.caltech.edu/records/j9vxm-pc073",
"eprint_id": 122042,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:59:39",
"lastmod": "2026-03-27 19:31:26",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Koplitz-Brad",
"name": {
"family": "Koplitz",
"given": "Brad"
},
"orcid": "0000-0001-5530-2872"
},
{
"id": "Johnson-Jared",
"name": {
"family": "Johnson",
"given": "Jared"
},
"orcid": "0000-0002-2630-9490"
},
{
"id": "Williams-Benjamin-F",
"name": {
"family": "Williams",
"given": "Benjamin F."
},
"orcid": "0000-0002-7502-0597"
},
{
"id": "D\u00edaz-Rodr\u00edguez-Mariangelly",
"name": {
"family": "D\u00edaz-Rodr\u00edguez",
"given": "Mariangelly"
},
"orcid": "0000-0002-4652-5983"
},
{
"id": "Murphy-Jeremiah-W",
"name": {
"family": "Murphy",
"given": "Jeremiah W."
},
"orcid": "0000-0003-1599-5656"
},
{
"id": "Lazzarini-Margaret",
"name": {
"family": "Lazzarini",
"given": "Margaret"
},
"orcid": "0000-0003-3252-352X"
},
{
"id": "Guzman-Joseph",
"name": {
"family": "Guzman",
"given": "Joseph"
},
"orcid": "0000-0001-8878-4994"
},
{
"id": "Dalcanton-Julianne-J",
"name": {
"family": "Dalcanton",
"given": "Julianne J."
},
"orcid": "0000-0002-1264-2006"
},
{
"id": "Dolphin-Andrew-E",
"name": {
"family": "Dolphin",
"given": "Andrew"
},
"orcid": "0000-0001-8416-4093"
},
{
"id": "Durbin-Meredith-J",
"name": {
"family": "Durbin",
"given": "Meredith J."
},
"orcid": "0000-0001-7531-9815"
}
]
},
"title": "The Masses of Supernova Remnant Progenitors in M33",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nSupport for this work was provided by NASA through grants GO-14610 and GO-15216 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.\n\nPublished - Koplitz_2023_ApJ_949_32.pdf
",
"abstract": "Using resolved optical stellar photometry from the Panchromatic Hubble Andromeda Treasury Triangulum Extended Region survey, we measured the star formation history near the position of 85 supernova remnants (SNRs) in M33. We constrained the progenitor masses for 60 of these SNRs, finding that the remaining 25 remnants had no local star formation in the last 56 Myr, consistent with core-collapse supernovae, making them potential Type Ia candidates. We then infer a progenitor mass distribution from the age distribution, assuming single star evolution. We find that the progenitor mass distribution is consistent with being drawn from a power law with an index of -2.9_(-1.0)^(+1.2). Additionally, we infer a minimum progenitor mass of 7.1_(-0.2)^(+0.1) M_\u2299 from this sample, consistent with several previous studies, providing further evidence that stars with ages older than the lifetimes of single 8 M\u2299 stars are producing supernovae.",
"date": "2023-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "949",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 32",
"id_number": "CaltechAUTHORS:20230628-332770500.12",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230628-332770500.12",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "HST-GO-14610"
},
{
"agency": "NASA",
"grant_number": "HST-GO-15216"
},
{
"agency": "NASA",
"grant_number": "NAS 5-26555"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acc249",
"primary_object": {
"basename": "Koplitz_2023_ApJ_949_32.pdf",
"url": "https://authors.library.caltech.edu/records/j9vxm-pc073/files/Koplitz_2023_ApJ_949_32.pdf"
},
"pub_year": "2023",
"author_list": "Koplitz, Brad; Johnson, Jared; et al."
},
{
"id": "https://authors.library.caltech.edu/records/pg73s-3pr42",
"eprint_id": 121582,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:48:39",
"lastmod": "2025-11-22 02:32:15",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bucciantini-Niccol\u00f3",
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f3"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f3"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Sgr\u00f3",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Watanabe",
"given": "Eri"
},
"orcid": "0000-0003-0622-8703"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Slane",
"given": "Patrick O."
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Silvestri",
"given": "Stefano"
},
"orcid": "0000-0002-8665-0105"
},
{
"name": {
"family": "Pacciani",
"given": "Luigi"
},
"orcid": "0000-0001-6897-5996"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "de O\u00f1a Wilhelmi",
"given": "Emma"
},
"orcid": "0000-0002-5401-0744"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Wong",
"given": "Josephine"
},
"orcid": "0000-0001-6395-2066"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Agudo",
"given": "Ivan"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting J."
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dovciak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Hayashida-Kiyoshi",
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru B."
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kaaret",
"given": "Philip E."
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Doug"
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicolas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Simultaneous space and phase resolved X-ray polarimetry of the Crab pulsar and nebula",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astronomy and Astrophysics",
"note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2023. \n\nThe IXPE is a joint US and Italian mission. The US contribution is supported by NASA and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract no. NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract no. ASI-OHBI-2017-12-I.0, agreement nos. ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreement nos. ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). The research at Boston University was supported in part by National Science Foundation grant no. AST-2108622. Part of the French contributions is supported by the Scientific Research National Center (CNRS) and the French spatial agency (CNES). I.A. acknowledges financial support from the Spanish 'Ministerio de Ciencia e Innovaci\u00f3n' (grant no. MCIN/AEI/ 10.13039/501100011033) through the Center of Excellence Severo Ochoa award for the Instituto de Astrof\u00edsica de Andaluc\u00eda-CSIC (grant no. CEX2021-001131-S), and through grant nos. PID2019-107847RB-C44 and PID2022-139117NB-C44. C.-Y.N. is supported by a GRF grant from the Hong Kong Government under no. HKU 17305419. N.B. was supported by the INAF MiniGrant 'PWNnumpol - Numerical Studies of Pulsar Wind Nebulae in The Light of IXPE'. J.H. acknowledges support from the Natural Sciences and Engineering Research Council of Canada through a Discovery Grant, the Canadian Space Agency through the co-investigator grant programme, and computational resources and services provided by Compute Canada, Advanced Research Computing at the University of British Columbia, and the SciServer science platform. S.G. and E.W. were supported by grant nos. JSPS KAKENHI JP 19H00696 and 22K14068. \n\nContributions. N.B. led the data analysis and the writing of the paper. R.F., M.B., J.R., L.P. and F.M. contributed to data analysis and data calibration. N.D.L., C.S., N.O., T.K., T.M., S.G. and E.W. contributed to data analysis and results interpretation. M.C.W., M.N., S.S., E.D.O.W., F.X., J.H., R.W.R., P.T., A.P. and H.L.M. contributed to text revision and data interpretation. L.B. and M.P.-R. contributed to software development. The remaining members of the IXPE collaboration contributed to the design of the mission, to the calibration of the instrument, to defining its science case and to the planning of the observations. All authors provided inputs and comments on the paper. \n\nData availability. Data from the Crab PSR and nebula observation are available in the HEASARC IXPE Data Archive (https://heasarc.gsfc.nasa.gov/docs/ixpe/archive/). Additional data are available in the Supplementary Information and from figshare at https://doi.org/10.6084/m9.figshare.22203163. Source data are provided with this paper. \n\nCode availability. The ixpeobssim software and documentation can be downloaded at https://github.com/lucabaldini/ixpeobssim. Other information supporting the findings of this study, and specific data-reduction pipelines, are available from the corresponding author upon request. \n\nThe authors declare no competing interests.",
"abstract": "The Crab pulsar and its nebula are among the most studied astrophysical systems, and constitute one of the most promising environments where high-energy processes and particle acceleration can be investigated. They are the only objects for which significant X-ray polarization was detected in the past. Here we present the Imaging X-ray Polarimetry Explorer (IXPE) observation of the Crab pulsar and nebula. The total pulsar pulsed emission in the [2\u20138]\u2009keV energy range is unpolarized. Significant polarization up to 15% is detected in the core of the main peak. The nebula has a total space integrated polarized degree of 20% and polarization angle of 145\u00b0. The polarized maps show a large variation in the local polarization, and regions with a polarized degree up to 45\u201350%. The polarization pattern suggests a predominantly toroidal magnetic field. Our findings for the pulsar are inconsistent with most inner magnetospheric models, and suggest emission is more likely to come from the wind region. For the nebula, the polarization map suggests a patchy distribution of turbulence, uncorrelated with the intensity, in contrast with simple expectations from numerical models.",
"date": "2023-05",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "7",
"number": "5",
"publisher": "Nature Publishing Group",
"pagerange": "602-610",
"id_number": "CaltechAUTHORS:20230526-436870000.28",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230526-436870000.28",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "NSF",
"grant_number": "AST-2108622"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "MCIN/AEI/10.13039/501100011033"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "Severo Ochoa Centre of Excellence",
"grant_number": "CEX2021-001131-S"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "PID2019-107847RB-C44"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCIN)",
"grant_number": "PID2022-139117NB-C44"
},
{
"agency": "Research Grants Council of Hong Kong",
"grant_number": "HKU 17305419"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "Canadian Space Agency (CSA)"
},
{
"agency": "Compute Canada"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "19H00696"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "22K14068"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41550-023-01936-8",
"pub_year": "2023",
"author_list": "Bucciantini, Niccol\u00f3; Ferrazzoli, Riccardo; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ap1ck-mbb72",
"eprint_status": "archive",
"datestamp": "2023-10-27 20:20:07",
"lastmod": "2025-11-22 02:35:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Malandraki-Olga-E",
"name": {
"family": "Malandraki",
"given": "O. E."
},
"orcid": "0000-0002-4751-6835"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Mitchell-John-Grant",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Chhiber-Rohit",
"name": {
"family": "Chhiber",
"given": "R."
},
"orcid": "0000-0002-7174-6948"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Rodr\u00edguez-Pacheco-Javier",
"name": {
"family": "Rodr\u00edguez-Pacheco",
"given": "J."
},
"orcid": "0000-0002-4240-1115"
},
{
"id": "Wimmer-Schweingruber-Robert-F",
"name": {
"family": "Wimmer-Schweingruber",
"given": "R. F."
},
"orcid": "0000-0002-7388-173X"
},
{
"id": "Ho-George-C",
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
}
]
},
"title": "Unexpected energetic particle observations near the Sun by Parker Solar Probe and Solar Orbiter",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Condensed Matter Physics",
"note": "\u00a9 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
\n\nParker Solar Probe was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (Contract No. NNN06AA01C). We thank everyone that helped make the IS\u2299IS instrument suite and PSP mission possible. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois. Solar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. Javier Rodr\u00edguez-Pacheco acknowledges the financial support by the Spanish Ministerio de Ciencia, Innovac\u00f3n y Universidades FEDER/MCIU/AEI Projects ESP2017-88436-R and PID2019-104863RB- I00/AEI/10.13039/501100011033 and by the European Union's Horizon 2020 research and innovation program under Grant No. 101004159 (SERPENTINE). Robert F. Wimmer-Schweingruber thanks the German Space Agency (Deutsches Zentrum f\u00fcr Luft- und Raumfahrt) for their support of Grant No. 50OT2002. Rohit Chhiber acknowledges support from NASA Grant Nos. 80NSSC18K1648 and 80NSSC22K1020, and the PSP/IS\u2299IS project (Contract No. NNN06AA01C) via a subcontract to the University of Delaware from Princeton University (SUB0000165).
\n\nOlga E. Malandraki: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). Christina M. S. Cohen: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). Joe Giacalone: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). John G. Mitchell: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). Rohit Chhiber: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). David J. McComas: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). Javier Rodr\u00edguez-Pacheco: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). Robert F. Wimmer-Schweingruber: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal). George C. Ho: Writing \u2013 original draft (equal); Writing \u2013 review & editing (equal).
\n\nData sharing is not applicable to this article as no new data were created or analyzed in this study.
\n\nThe authors have no conflicts to disclose.
\n\nSpecial Collection: Plasma Physics of the Sun in Honor of Eugene Parker
",
"abstract": "Solar energetic particles (SEPs) from suprathermal (few keV) up to relativistic (\u223cfew GeV) energies are accelerated at the Sun in association with solar flares and coronal mass ejection-driven shock waves. Although our knowledge of the origin, acceleration, and transport of these particles from close to the Sun through the interplanetary medium has advanced dramatically in the last 40\u2009years, many puzzles have still remained unsolved due to the scarcity of in situ measurements well inside 1\u2009AU. Furthermore, energetic particle intensity enhancements associated with high-speed streams or stream interaction regions (SIRs) have been routinely observed at interplanetary spacecraft near Earth orbit since the 1960s. Since only a small sample of SIR events were observed by the Helios spacecraft inside 1\u2009AU, additional observations well inside 1\u2009AU were also needed to further investigate the energization and transport effects of SIR-associated ions and to compare with expectations from contemporary SIR-associated particle acceleration and transport models and theories. The Solar Orbiter (SolO) and Parker Solar Probe (PSP) pioneering missions have been providing unprecedented measurements of energetic particles in the near-Sun environment. This review presents the unexpected observations of SEP and SIR-related ion events as measured by the PSP/IS\u2299IS and SolO/EPD experiments, which revealed surprises that challenge our understanding.",
"date": "2023-05",
"date_type": "published",
"publication": "Physics of Plasmas",
"volume": "30",
"number": "5",
"publisher": "American Institute of Physics",
"pagerange": "050501",
"issn": "1070-664X",
"official_url": "https://authors.library.caltech.edu/records/ap1ck-mbb72",
"funders": {
"items": [
{
"grant_number": "NNN06AA01C"
},
{
"grant_number": "ESP2017-88436-R"
},
{
"grant_number": "PID2019-104863RB- I00/AEI/10.13039/501100011033"
},
{
"grant_number": "101004159"
},
{
"grant_number": "50OT2002"
},
{
"grant_number": "80NSSC18K1648"
},
{
"grant_number": "80NSSC22K1020"
},
{
"grant_number": "SUB0000165"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1063/5.0147683",
"primary_object": {
"basename": "050501_1_5.0147683.pdf",
"url": "https://authors.library.caltech.edu/records/ap1ck-mbb72/files/050501_1_5.0147683.pdf"
},
"pub_year": "2023",
"author_list": "Malandraki, O. E.; Cohen, C. M. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/25kzg-ra964",
"eprint_id": 121500,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:42:39",
"lastmod": "2023-10-20 15:30:20",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Forsblom-Sofia-V",
"name": {
"family": "Forsblom",
"given": "Sofia V."
},
"orcid": "0000-0001-9167-2790"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Malacaria",
"given": "Christian"
},
"orcid": "0000-0002-0380-0041"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Mushtukov",
"given": "Alexander A."
},
"orcid": "0000-0003-2306-419X"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Rogantini",
"given": "Daniele"
},
"orcid": "0000-0002-5359-9497"
},
{
"name": {
"family": "Suleimanov",
"given": "Valery F."
},
"orcid": "0000-0003-3733-7267"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Ng",
"given": "Chi-Yung"
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Sunyaev",
"given": "Rashid A."
},
"orcid": "0000-0002-2764-7192"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "IXPE Observations of the Quintessential Wind-accreting X-Ray Pulsar Vela X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). \n\nWe acknowledge support from the RSF grant 19-12-00423 (SST), the Academy of Finland grants 333112, 349144, 349373, and 349906 (JP, SST), the German Academic Exchange Service (DAAD) travel grant 57525212 (VD, VFS), and the German Research Foundation (DFG) grant WE 1312/53-1 (VFS). \n\nFacilities: IXPE. - \n\nSoftware: astropy (Astropy Collaboration et al. 2013, 2018), xspec (Arnaud 1996), ixpeobssim (Baldini et al. 2022).\n\nPublished - Forsblom_2023_ApJL_947_L20.pdf
",
"abstract": "The radiation from accreting X-ray pulsars was expected to be highly polarized, with some estimates for the polarization degree of up to 80%. However, phase-resolved and energy-resolved polarimetry of X-ray pulsars is required in order to test different models and to shed light on the emission processes and the geometry of the emission region. Here we present the first results of the observations of the accreting X-ray pulsar Vela X-1 performed with the Imaging X-ray Polarimetry Explorer. Vela X-1 is considered to be the archetypal example of a wind-accreting, high-mass X-ray binary system, consisting of a highly magnetized neutron star accreting matter from its supergiant stellar companion. The spectropolarimetric analysis of the phase-averaged data for Vela X-1 reveals a polarization degree (PD) of 2.3% \u00b1 0.4% at the polarization angle (PA) of \u221247.\u00b03 \u00b1 5.\u00b04. A low PD is consistent with the results obtained for other X-ray pulsars and is likely related to the inverse temperature structure of the neutron star atmosphere. The energy-resolved analysis shows the PD above 5 keV reaching 6%\u201310% and a \u223c90\u00b0 difference in the PA compared to the data in the 2\u20133 keV range. The phase-resolved spectropolarimetric analysis finds a PD in the range 0%\u20139% with the PA varying between \u221280\u00b0 and 40\u00b0.",
"date": "2023-04-20",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "947",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L20",
"id_number": "CaltechAUTHORS:20230523-606156800.6",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230523-606156800.6",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
},
{
"agency": "Academy of Finland",
"grant_number": "349144"
},
{
"agency": "Academy of Finland",
"grant_number": "349373"
},
{
"agency": "Academy of Finland",
"grant_number": "349906"
},
{
"agency": "Deutscher Akademischer Austauschdienst (DAAD)",
"grant_number": "57525212"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "WE 1312/53-1"
},
{
"agency": "Russian Science Foundation",
"grant_number": "19-12-00423"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"corp_creators": {
"items": [
"IXPE Collaboration"
]
},
"doi": "10.3847/2041-8213/acc391",
"primary_object": {
"basename": "Forsblom_2023_ApJL_947_L20.pdf",
"url": "https://authors.library.caltech.edu/records/25kzg-ra964/files/Forsblom_2023_ApJL_947_L20.pdf"
},
"pub_year": "2023",
"author_list": "Forsblom, Sofia V.; Poutanen, Juri; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6zqjb-6fm13",
"eprint_id": 121397,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:42:34",
"lastmod": "2025-11-22 02:25:10",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Yun-S-B",
"name": {
"family": "Yun",
"given": "S. B."
}
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "M. C."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "G."
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "S. N."
},
"orcid": "0000-0002-8403-0041"
}
]
},
"title": "Revealing the Spectral State Transition of the Clocked Burster, GS 1826-238, with NuSTAR StrayCats",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThis work was supported by the National Aeronautics and Space Administration (NASA) under grant number 80NSSC19K1023 issued through the NNH18ZDA001N Astrophysics Data Analysis Program (ADAP). This research was performed at the California Institute of Technology (Caltech) under the Summer Undergraduate Research Fellowship (SURF) program. \n\nAdditionally, this work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for their support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.\n\nPublished - Yun_2023_ApJ_947_81.pdf
",
"abstract": "We present the long-term analysis of GS 1826-238, a neutron star X-ray binary known as the Clocked Burster, using data from NuSTAR StrayCats. StrayCats, a catalog of NuSTAR stray light data, contains data from bright, off-axis X-ray sources that have not been focused by the NuSTAR optics. We obtained stray light observations of the source from 2014\u20132021, reduced and analyzed the data using nustar-gen-utils Python tools, demonstrating the transition of the source from the island atoll state to a banana branch. We also present the light-curve analysis of Type I X-ray bursts from the Clocked Burster and show that the bursts from the banana/soft state are systematically shorter in duration than those from the island/hard state and have a higher burst fluence. From our analysis, we note an increase in the mass accretion rate of the source, and a decrease in burst frequency with the transition.",
"date": "2023-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "947",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 81",
"id_number": "CaltechAUTHORS:20230515-138512000.10",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230515-138512000.10",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K1023"
},
{
"agency": "NASA",
"grant_number": "NNH18ZDA001N"
},
{
"agency": "Caltech Summer Undergraduate Research Fellowship (SURF)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/acb689",
"primary_object": {
"basename": "Yun_2023_ApJ_947_81.pdf",
"url": "https://authors.library.caltech.edu/records/6zqjb-6fm13/files/Yun_2023_ApJ_947_81.pdf"
},
"pub_year": "2023",
"author_list": "Yun, S. B.; Grefenstette, B. W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/h6d59-qzq73",
"eprint_id": 122145,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:35:09",
"lastmod": "2025-11-22 02:28:47",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Israel-GianLuca",
"name": {
"family": "Israel",
"given": "G. L."
},
"orcid": "0000-0001-5480-6438"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Imbrogno-Matteo",
"name": {
"family": "Imbrogno",
"given": "M."
},
"orcid": "0000-0001-8688-9784"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Salvaterra-Ruben",
"name": {
"family": "Salvaterra",
"given": "R."
},
"orcid": "0000-0002-9393-8078"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Rodr\u00edguez-Castillo-Guillermo-Andres-A",
"name": {
"family": "Rodr\u00edguez Castillo",
"given": "G. A."
}
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "N. A."
},
"orcid": "0000-0002-2956-6062"
}
]
},
"title": "Probing the nature of the low state in the extreme ultraluminous X-ray pulsar NGC 5907 ULX1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication. \n\nThe authors would like to thank the referee for their useful feedback, which helped to improve the final version of the manuscript. D.J.W. acknowledges support from an STFC Ernest Rutherford Fellowship. T.P.R. acknowledges support from the Science and Technology Facilities Council (STFC) as part of the consolidated grant award ST/000244/1. This research has also made use of data obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States, and has also made use of public data from the Swift data archive. We thank Kyle Parfrey for the useful discussion. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester.\n\nPublished - aa45048-22.pdf
",
"abstract": "NGC 5907 ULX1 is the most luminous ultra-luminous X-ray pulsar (ULXP) known to date, reaching luminosities in excess of 10\u2074\u00b9 erg s\u207b\u00b9. The pulsar is known for its fast spin-up during the on-state. Here, we present a long-term monitoring of the X-ray flux and the pulse period between 2003 and 2022. We find that the source was in an off- or low-state between mid-2017 to mid-2020. During this state, our pulse period monitoring shows that the source had spun down considerably. We interpret this spin-down as likely being due to the propeller effect, whereby accretion onto the neutron star surface is inhibited. Using state-of-the-art accretion and torque models, we use the spin-up and spin-down episodes to constrain the magnetic field. For the spin-up episode, we find solutions for magnetic field strengths of either around 10\u00b9\u00b2 G or 1013 G, however, the strong spin-down during the off-state seems only to be consistent with a very high magnetic field, namely, > 10\u00b9\u00b3 G. This is the first time a strong spin-down is seen during a low flux state in a ULXP. Based on the assumption that the source entered the propeller regime, this gives us the best estimate so far for the magnetic field of NGC 5907 ULX1.",
"date": "2023-04",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "672",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A140",
"id_number": "CaltechAUTHORS:20230705-476466000.6",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230705-476466000.6",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/000244/1"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202245048",
"primary_object": {
"basename": "aa45048-22.pdf",
"url": "https://authors.library.caltech.edu/records/h6d59-qzq73/files/aa45048-22.pdf"
},
"pub_year": "2023",
"author_list": "F\u00fcrst, F.; Walton, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/hd5jb-ybh10",
"eprint_id": 121120,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:22:41",
"lastmod": "2025-11-22 02:36:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Nitta-Nariaki-V",
"name": {
"family": "Nitta",
"given": "Nariaki V."
},
"orcid": "0000-0001-6119-0221"
},
{
"id": "Bu\u010d\u00edk-Radoslav",
"name": {
"family": "Bu\u010d\u00edk",
"given": "Radoslav"
},
"orcid": "0000-0001-7381-6949"
},
{
"id": "Mason-Glenn-M",
"name": {
"family": "Mason",
"given": "Glenn M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "Ho-George-C",
"name": {
"family": "Ho",
"given": "George C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "G\u00f3mez-Herrero-Ra\u00fal",
"name": {
"family": "G\u00f3mez-Herrero",
"given": "Ra\u00fal"
},
"orcid": "0000-0002-5705-9236"
},
{
"id": "Wang-Linghua",
"name": {
"family": "Wang",
"given": "Linghua"
},
"orcid": "0000-0001-7309-4325"
},
{
"id": "Balmaceda-Laura-A",
"name": {
"family": "Balmaceda",
"given": "Laura A."
},
"orcid": "0000-0003-1162-5498"
}
]
},
"title": "Solar activities associated with \u00b3He-rich solar energetic particle events observed by Solar Orbiter",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astronomy and Astrophysics",
"note": "\u00a9 2023 Nitta, Bu\u010d\u00edk, Mason, Ho, Cohen, G\u00f3mez-Herrero, Wang and Balmaceda. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. \n\nWe acknowledge the International Space Science Institute (ISSI) for their support of International Team \"Origins of \u00b3He-Rich Solar Energetic Particles\" (https://www.issibern.ch/teams/origin3henrgpart/). \n\nThe work of NN was supported by NASA grants 80NSSC18K1126 and 80NSSC20K0287. RB acknowledges support from a NASA grant 80NSSC22K0757. CC was supported by NASA grants 80NSSC18K0223 and 80NSSC21K1512. RG-H acknowledges the financial support of the Spanish MINCIN Project PID2019-104863RBI00/AEI/10.13039/501100011033. \n\nConflict of interest. Author NN was employed by Lockheed Martin Advanced Technology Center. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\n\nPublished - fspas-10-1148467.pdf
Supplemental Material - Video_1.mp4
Supplemental Material - Video_2.mp4
Supplemental Material - Video_3.MP4
Supplemental Material - Video_4.MP4
",
"abstract": "A series of \u00b3He-rich solar energetic particle (SEP) events was observed by Solar Orbiter in May 2021 at a radial distance of 0.95 AU. An isolated active region AR 12824 was likely the ultimate source of these SEP events. The period of the enhanced flux of \u00b3He was also a period of frequent type III bursts in the decametric-hectometric range, confirming their close relationship. As in past studies, we try to find the solar activities possibly responsible for \u00b3He-rich SEP events, using the type III bursts close to the particle injection times estimated from the velocity dispersion. But this exercise is not as straightforward as in many of the past studies since the region produced many more type III bursts and jet-like eruptions than the SEP injections. We may generalize the solar activities for the \u00b3He-rich SEP events in question as coronal jets, but their appearances do not necessarily conform to classic jets that consist of a footpoint and a spire. Conversely, such jets often did not accompany type III bursts. The areas that produced jet-like eruptions changed within the active region from the first to the second set of \u00b3He-rich SEP events, which may be related to the extended coronal mass ejection that launched stealthily.",
"date": "2023-03-14",
"date_type": "published",
"publication": "Frontiers in Astronomy and Space Sciences",
"volume": "10",
"publisher": "Frontiers Media",
"pagerange": "Art. No. 1148467",
"id_number": "CaltechAUTHORS:20230420-698969800.7",
"issn": "2296-987X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230420-698969800.7",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC18K1126"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0287"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0757"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0223"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1512"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MINCIN)",
"grant_number": "PID2019-104863RBI00/AEI/10.13039/501100011033"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3389/fspas.2023.1148467",
"primary_object": {
"basename": "fspas-10-1148467.pdf",
"url": "https://authors.library.caltech.edu/records/hd5jb-ybh10/files/fspas-10-1148467.pdf"
},
"related_objects": [
{
"basename": "Video_1.mp4",
"url": "https://authors.library.caltech.edu/records/hd5jb-ybh10/files/Video_1.mp4"
},
{
"basename": "Video_2.mp4",
"url": "https://authors.library.caltech.edu/records/hd5jb-ybh10/files/Video_2.mp4"
},
{
"basename": "Video_3.MP4",
"url": "https://authors.library.caltech.edu/records/hd5jb-ybh10/files/Video_3.MP4"
},
{
"basename": "Video_4.MP4",
"url": "https://authors.library.caltech.edu/records/hd5jb-ybh10/files/Video_4.MP4"
}
],
"pub_year": "2023",
"author_list": "Nitta, Nariaki V.; Bu\u010d\u00edk, Radoslav; et al."
},
{
"id": "https://authors.library.caltech.edu/records/sbjtv-32060",
"eprint_id": 120562,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:19:06",
"lastmod": "2025-11-22 03:46:29",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ferrazzoli-Riccardo",
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Prokhorov",
"given": "Dmitry"
}
},
{
"name": {
"family": "Zhou",
"given": "Ping"
},
"orcid": "0000-0002-5683-822X"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Asakura",
"given": "Kazunori"
}
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Kaaret",
"given": "Philip E."
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Silvestri",
"given": "Stefano"
},
"orcid": "0000-0002-6125-5424"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Yang",
"given": "Yi-Jung"
},
"orcid": "0000-0001-9108-573X"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chien-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver"
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "X-Ray Polarimetry Reveals the Magnetic-field Topology on Sub-parsec Scales in Tycho's Supernova Remnant",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nIXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). \n\nJ. Vink & D.Prokhorov are supported by funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004131 (SHARP). P.S. acknowledges support from NASA contract NAS8-03060. P.Z. acknowledges the support from NWO Veni Fellowship grant No. 639.041.647 and NSFC grant No. 12273010 C.-Y.N. and Y.J.Y. are supported by a GRF grant of the Hong Kong Government under HKU 17305419. We thank the anonymous reviewer for their useful comments and suggestions. \n\nFacilities: IXPE - , Chandra. - \n\nSoftware: ixpeobssim (Baldini et al. 2022), CIAO (Fruscione et al. 2006), XSPEC (Arnaud 1996).\n\nPublished - Ferrazzoli_2023_ApJ_945_52.pdf
",
"abstract": "Supernova remnants are commonly considered to produce most of the Galactic cosmic rays via diffusive shock acceleration. However, many questions regarding the physical conditions at shock fronts, such as the magnetic-field morphology close to the particle acceleration sites, remain open. Here we report the detection of a localized polarization signal from some synchrotron X-ray emitting regions of Tycho's supernova remnant made by the Imaging X-ray Polarimetry Explorer. The derived degree of polarization of the X-ray synchrotron emission is 9% \u00b1 2% averaged over the whole remnant, and 12% \u00b1 2% at the rim, higher than the value of polarization of 7%\u20138% observed in the radio band. In the west region, the degree of polarization is 23% \u00b1 4%. The degree of X-ray polarization in Tycho is higher than for Cassiopeia A, suggesting a more ordered magnetic field or a larger maximum turbulence scale. The measured tangential direction of polarization corresponds to the radial magnetic field, and is consistent with that observed in the radio band. These results are compatible with the expectation of turbulence produced by an anisotropic cascade of a radial magnetic field near the shock, where we derive a magnetic-field amplification factor of 3.4 \u00b1 0.3. The fact that this value is significantly smaller than those expected from acceleration models is indicative of highly anisotropic magnetic-field turbulence, or that the emitting electrons either favor regions of lower turbulence, or accumulate close to where the orientation of the magnetic field is preferentially radially oriented due to hydrodynamical instabilities.",
"date": "2023-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "945",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 52",
"id_number": "CaltechAUTHORS:20230328-707475900.56",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230328-707475900.56",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101004131"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "639.041.647"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12273010"
},
{
"agency": "University of Hong Kong",
"grant_number": "HKU 17305419"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acb496",
"primary_object": {
"basename": "Ferrazzoli_2023_ApJ_945_52.pdf",
"url": "https://authors.library.caltech.edu/records/sbjtv-32060/files/Ferrazzoli_2023_ApJ_945_52.pdf"
},
"pub_year": "2023",
"author_list": "Ferrazzoli, Riccardo; Slane, Patrick; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ssmp9-me185",
"eprint_id": 121132,
"eprint_status": "archive",
"datestamp": "2023-08-22 20:16:21",
"lastmod": "2025-11-22 02:34:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Paterson-Sarah-J",
"name": {
"family": "Paterson",
"given": "Sarah"
},
"orcid": "0000-0003-2147-9586"
},
{
"id": "Hannah-Iain-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Hudson-Hugh-S",
"name": {
"family": "Hudson",
"given": "Hugh S."
},
"orcid": "0000-0001-5685-1283"
},
{
"id": "Krucker-S\u00e4m",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
},
"orcid": "0000-0002-2002-9180"
},
{
"id": "Glesener-Lindsay",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "White-Stephen-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
},
{
"id": "Smith-David-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
}
]
},
"title": "The First Survey of Quiet Sun Features Observed in Hard X-Rays with NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nThis paper made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NUSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). Hinode is a Japanese mission developed and launched by ISAS/JAXA, with NAOJ as domestic partner and NASA and UKSA as international partners. It is operated by these agencies in co-operation with ESA and NSC (Norway). AIA on the Solar Dynamics Observatory is part of NASA's Living with a Star program. This research has made use of SunPy, an open-source and free community-developed solar data analysis package written in Python (SunPy Community et al., 2015). This research made use of Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al., 2018, 2013). The authors would also like to thank Kathy Reeves for co-ordinating the Hinode/XRT observations. \n\nSP acknowledges support from the UK's Science and Technology Facilities Council (STFC) doctoral training grant (ST/T506102/1). IGH acknowledges support from a Royal Society University Fellowship (URF/R/180010) and STFC grant (ST/T000422/1). \n\nContributions. SP did the data processing and applied the analysis techniques described and wrote the manuscript text. IGH developed the demreg analysis techniques and helped with the spectral analysis. All authors revised the manuscript. \n\nThe authors declare no competing interests.\n\nPublished - s11207-023-02135-4.pdf
",
"abstract": "We present the first survey of quiet Sun features observed in hard X-rays (HXRs), using the Nuclear Spectroscopic Telescope ARray (NuSTAR), a HXR focusing optics telescope. The recent solar minimum, combined with NuSTAR's high sensitivity, has presented a unique opportunity to perform the first HXR imaging spectroscopy on a range of features in the quiet Sun. By studying the HXR emission of these features, we can detect or constrain the presence of high temperature (>\u20095 MK) or non-thermal sources, to help understand how they relate to larger, more energetic solar phenomena, and determine their contribution to heating the solar atmosphere. We report on several features observed in the 28 September 2018 NuSTAR full-disk quiet Sun mosaics, the first of the NuSTAR quiet Sun observing campaigns, which mostly include steady features of X-ray bright points and an emerging flux region, which later evolved into an active region, as well as a short-lived jet. We find that the features' HXR spectra are well fitted with isothermal models with temperatures ranging between 2.0\u2009\u2013\u20093.2 MK. Combining the NuSTAR data with softer X-ray emission from Hinode/XRT and EUV from SDO/AIA, we recover the differential emission measures, confirming little significant emission above 4 MK. The NuSTAR HXR spectra allow us to constrain the possible non-thermal emission that would still be consistent with a null HXR detection. We found that for only one of the features (the jet) was there a potential non-thermal upper limit capable of powering the heating observed. However, even here, the non-thermal electron distribution had to be very steep (effectively mono-energetic) with a low energy cut-off between 3\u2009\u2013\u20094\u00a0keV.",
"date": "2023-03",
"date_type": "published",
"publication": "Solar Physics",
"volume": "298",
"number": "3",
"publisher": "Springer",
"pagerange": "Art. No. 47",
"id_number": "CaltechAUTHORS:20230420-956212500.5",
"issn": "0038-0938",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230420-956212500.5",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T506102/1"
},
{
"agency": "Royal Society",
"grant_number": "URF/R/180010"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T000422/1"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1007/s11207-023-02135-4",
"primary_object": {
"basename": "s11207-023-02135-4.pdf",
"url": "https://authors.library.caltech.edu/records/ssmp9-me185/files/s11207-023-02135-4.pdf"
},
"pub_year": "2023",
"author_list": "Paterson, Sarah; Hannah, Iain G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kwakt-mtg81",
"eprint_id": 120742,
"eprint_status": "archive",
"datestamp": "2023-08-22 19:03:23",
"lastmod": "2025-11-22 02:41:08",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zane-Silvia",
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Gonz\u00e1lez\u2013Caniulef",
"given": "Denis"
},
"orcid": "0000-0001-5848-0180"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Uchiyama",
"given": "Keisuke"
},
"orcid": "0000-0002-7752-9389"
},
{
"name": {
"family": "Ng",
"given": "Mason"
},
"orcid": "0000-0002-0940-6563"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"id": "Caiazzo-Ilaria",
"name": {
"family": "Caiazzo",
"given": "Ilaria"
},
"orcid": "0000-0002-4770-5388"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Gau",
"given": "Ephraim"
},
"orcid": "0000-0002-5250-2710"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Kislat",
"given": "Fabian"
},
"orcid": "0000-0001-7477-0380"
},
{
"name": {
"family": "Kelly",
"given": "Ruth"
},
"orcid": "0000-0002-5004-3573"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Chen",
"given": "Chieng-Ting"
},
"orcid": "0000-0002-4945-5079"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kaaret",
"given": "Philip"
},
"orcid": "0000-0002-3638-0637"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Roberts",
"given": "Oliver J."
},
"orcid": "0000-0002-7150-9061"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f3",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
},
"orcid": "0000-0002-2954-4461"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
}
]
},
"title": "A Strong X-Ray Polarization Signal from the Magnetar 1RXS J170849.0-400910",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana; ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN). We thank K. C. Gendreau and Z. Arzoumanian for their help in scheduling NICER observations of the source. We acknowledge the use of public data from the Swift data archive, and we thank the Swift team for promptly scheduling a target of opportunity (ToO) observation. R.T. and R.T. acknowledge financial support from the Italian Ministry of University and Research (MUR) through grant PRIN 2017LJ39LM. D.G.-C., J.H., and I.C. acknowledge support from the Natural Sciences and Engineer Council of Canada and the Canadian Space Agency. M.N. acknowledges the support by NASA under award number 80GSFC21M0002. T.T. was supported by grant JSPS KAKENHI JP19H05609. H.K. and E.G. acknowledge NASA support under grants 80NSSC18K0264, 80NSSC22K1291, 80NSSC21K1817, and NNX16AC42G. We thank an anonymous referee for a careful reading of the paper. \n\nFacilities: IXPE - , Swift (XRT) - , NICER. -\n\nPublished - Zane_2023_ApJL_944_L27.pdf
",
"abstract": "Magnetars are the most strongly magnetized neutron stars, and one of the most promising targets for X-ray polarimetric measurements. We present here the first Imaging X-ray Polarimetry Explorer observation of the magnetar 1RXS J170849.0-400910, jointly analyzed with a new Swift observation and archival NICER data. The total (energy- and phase-integrated) emission in the 2\u20138 keV energy range is linerarly polarized, at a \u223c35% level. The phase-averaged polarization signal shows a marked increase with energy, ranging from \u223c20% at 2\u20133 keV up to \u223c80% at 6\u20138 keV, while the polarization angle remains constant. This indicates that radiation is mostly polarized in a single direction. The spectrum is well reproduced by a combination of either two thermal (blackbody) components or a blackbody and a power law. Both the polarization degree and angle also show a variation with the spin phase, and the former is almost anticorrelated with the source counts in the 2\u20138 and 2\u20134 keV bands. We discuss the possible implications and interpretations, based on a joint analysis of the spectral, polarization, and pulsation properties of the source. A scenario in which the surface temperature is not homogeneous, with a hotter cap covered by a gaseous atmosphere and a warmer region in a condensed state, provides a satisfactory description of both the phase- and energy-dependent spectro-polarimetric data. The (comparatively) small size of the two emitting regions, required to explain the observed pulsations, does not allow to reach a robust conclusion about the presence of vacuum birefringence effects.",
"date": "2023-02-20",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "944",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L27",
"id_number": "CaltechAUTHORS:20230411-764712100.2",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230411-764712100.2",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca (MIUR)",
"grant_number": "2017LJ39LM"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "Canadian Space Agency (CSA)"
},
{
"agency": "NASA",
"grant_number": "80GSFC21M0002"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP19H05609"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0264"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K1291"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1817"
},
{
"agency": "NASA",
"grant_number": "NNX16AC42G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/acb703",
"primary_object": {
"basename": "Zane_2023_ApJL_944_L27.pdf",
"url": "https://authors.library.caltech.edu/records/kwakt-mtg81/files/Zane_2023_ApJL_944_L27.pdf"
},
"pub_year": "2023",
"author_list": "Zane, Silvia; Taverna, Roberto; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4d7b6-n6x90",
"eprint_id": 120072,
"eprint_status": "archive",
"datestamp": "2023-08-22 19:02:30",
"lastmod": "2025-11-22 02:28:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Li-Gang",
"name": {
"family": "Li",
"given": "Gang"
},
"orcid": "0000-0003-4695-8866"
},
{
"id": "Shih-Albert-Y",
"name": {
"family": "Shih",
"given": "Albert Y."
},
"orcid": "0000-0001-6874-2594"
},
{
"id": "Allen-Robert-C",
"name": {
"family": "Allen",
"given": "Robert C."
},
"orcid": "0000-0003-2079-5683"
},
{
"id": "Ho-George-C",
"name": {
"family": "Ho",
"given": "George C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "Mihir"
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Dayeh-Maher-A",
"name": {
"family": "Dayeh",
"given": "Maher A."
},
"orcid": "0000-0001-9323-1200"
},
{
"id": "Mason-Glenn-M",
"name": {
"family": "Mason",
"given": "Glenn M."
},
"orcid": "0000-0003-2169-9618"
}
]
},
"title": "Modeling Solar Energetic Neutral Atoms from Solar Flares and CME-driven Shocks",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThis work is supported in part by NASA grants 80NSSC19K0075, 80NSSC19K0079, and 80NSSC20K1783 at UAH. Work at SwRI is partially supported by NASA LWS grants 80NSSC19K0079 and 80NSSC20K1815. Work at APL is partially supported by NASA contract 80MSFC19F0002.\n\nPublished - Li_2023_ApJ_944_196.pdf
",
"abstract": "We examine the production of energetic neutral atoms (ENAs) in solar flares and coronal mass ejection (CME)-driven shocks and their subsequent propagation to 1 au. Time profiles and fluence spectra of solar ENAs at 1 au are computed for two scenarios: (1) ENAs are produced downstream at CME-driven shocks, and (2) ENAs are produced at large-scale post-flare loops in solar flares. Both the time profiles and fluence spectra for these two scenarios are vastly different. Our calculations indicate that we can use solar ENAs as a new probe to examine the underlying acceleration process of solar energetic particles (SEPs) and to differentiate the two acceleration sites: large loops in solar flares and downstream of CME-driven shocks, in large SEP events.",
"date": "2023-02-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "944",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 196",
"id_number": "CaltechAUTHORS:20230315-645491100.4",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230315-645491100.4",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K0075"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0079"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1783"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1815"
},
{
"agency": "NASA",
"grant_number": "80MSFC19F0002"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acb494",
"primary_object": {
"basename": "Li_2023_ApJ_944_196.pdf",
"url": "https://authors.library.caltech.edu/records/4d7b6-n6x90/files/Li_2023_ApJ_944_196.pdf"
},
"pub_year": "2023",
"author_list": "Li, Gang; Shih, Albert Y.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0pkmn-pc203",
"eprint_id": 120228,
"eprint_status": "archive",
"datestamp": "2023-08-22 19:02:52",
"lastmod": "2025-11-22 03:13:32",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Strauss-Roelf-D",
"name": {
"family": "Strauss",
"given": "R. D."
},
"orcid": "0000-0002-0205-0808"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
}
]
},
"title": "The Modulation of Anomalous and Galactic Cosmic-Ray Oxygen over Successive Solar Cycle Minima",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThis work is based on research supported in part by the National Research Foundation of South Africa (NRF grant Nos. 119424, 120345, and 120847). Opinions expressed and conclusions arrived at are those of the authors and are not necessarily to be attributed to the NRF. The responsibility of the contents of this work is with the authors. R.A.L. acknowledges support from NASA grant 80NSSC18K0223. This work was also supported as a part of the Integrated Science Investigation of the Sun on NASA's Parker Solar Probe mission, under contract NNN06AA01C. Figures were prepared with Matplotlib (Hunter 2007) and certain calculations were done with NumPy (Harris et al. 2020). Sunspot number measurements were provided courtesy of the Royal Observatory of Belgium, Brussels. HCS tilt angle and solar polar magnetic field measurements were provided courtesy of the Wilcox Solar Observatory (WSO). WSO data used in this study were obtained via the website http://wso.stanford.edu at 2022:11:04_18:40:53 PDT, courtesy of J. T. Hoeksema. The WSO is currently supported by NASA.\n\nPublished - Strauss_2023_ApJ_944_114.pdf
",
"abstract": "Both the recent 2009 and 2020 solar minima were classified as unusually quiet and characterized with unusually high galactic cosmic-ray (GCR) levels. However, unlike the trends from previous decades, in which anomalous cosmic-ray (ACR) and GCR levels strongly agreed, the ACR intensities did not reach such high, record-setting levels. This discrepancy between the behavior of GCRs and ACRs is investigated in this work by simulating the acceleration and transport of GCR and ACR oxygen under different transport conditions. After using recent observations to constrain any remaining free parameters present in the model, we show that less turbulent conditions are characterized by higher GCR fluxes and lower ACR fluxes, due to less efficient ACR acceleration at the solar wind termination shock. We offer this as an explanation for the ACR/GCR discrepancy observed during 2009 and 2020, when compared to previous solar cycles.",
"date": "2023-02-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "944",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 114",
"id_number": "CaltechAUTHORS:20230321-821389800.30",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230321-821389800.30",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Research Foundation (South Africa)",
"grant_number": "119424"
},
{
"agency": "National Research Foundation (South Africa)",
"grant_number": "120345"
},
{
"agency": "National Research Foundation (South Africa)",
"grant_number": "120847"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0223"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acb53d",
"primary_object": {
"basename": "Strauss_2023_ApJ_944_114.pdf",
"url": "https://authors.library.caltech.edu/records/0pkmn-pc203/files/Strauss_2023_ApJ_944_114.pdf"
},
"pub_year": "2023",
"author_list": "Strauss, R. D.; Leske, R. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xkkgk-vzw61",
"eprint_id": 120028,
"eprint_status": "archive",
"datestamp": "2023-08-22 19:00:40",
"lastmod": "2026-03-27 18:27:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rout-Sandeep-K",
"name": {
"family": "Rout",
"given": "Sandeep K."
},
"orcid": "0000-0001-7590-5099"
},
{
"id": "Vadawale-Santosh",
"name": {
"family": "Vadawale",
"given": "Santosh"
},
"orcid": "0000-0002-2050-0913"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier"
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley"
},
"orcid": "0000-0002-8908-759X"
}
]
},
"title": "Revisiting the Galactic X-Ray Binary MAXI J1631\u2013479: Implications for High Inclination and a Massive Black Hole",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThis research is supported by the Physical Research Laboratory, which is funded by Dept. of Space, Govt. of India. This research has made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.\n\nPublished - Rout_2023_ApJ_944_68.pdf
",
"abstract": "X-ray spectroscopy of Galactic black hole binaries serves as a powerful tool to gain an overall understanding of the system. Not only can the properties of the accretion disk be studied in detail, the fundamental properties of the black hole such as spin and mass can also be measured. In this work we carry out a comprehensive spectral analysis of the\u00a0X-ray binary MAXI J1631\u2013479 using data from NICER and NuSTAR observatories. We trace the evolution of the accretion disk properties, such as density, ionization, and Fe abundance, as the source transitions from a disk-dominated soft state to a power-law-dominated hard intermediate state. As expected the disc ionization increased with hardness while the density and abundance (at solar values) remained unchanged. We provide strong constraints on the spin of the black hole (a > 0.996) and the inclination of the inner disk (50\u00b0\u201370\u00b0). We also use the soft-state NICER observations to constrain the black hole mass using distance estimates from optical observations. We find the probable mass of the black hole to be much higher than its X-ray binary counterparts with a conservative lower limit of 15 M_\u2299 at 4.5 kpc.",
"date": "2023-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "944",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 68",
"id_number": "CaltechAUTHORS:20230314-845495900.53",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230314-845495900.53",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Department of Space (India)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acaaa4",
"primary_object": {
"basename": "Rout_2023_ApJ_944_68.pdf",
"url": "https://authors.library.caltech.edu/records/xkkgk-vzw61/files/Rout_2023_ApJ_944_68.pdf"
},
"pub_year": "2023",
"author_list": "Rout, Sandeep K.; Vadawale, Santosh; et al."
},
{
"id": "https://authors.library.caltech.edu/records/aad88-fs891",
"eprint_id": 119306,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:58:10",
"lastmod": "2025-11-22 02:34:33",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Sharma-T",
"name": {
"family": "Sharma",
"given": "T."
}
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Khoo-L-Y",
"name": {
"family": "Khoo",
"given": "L. Y."
}
},
{
"id": "Matthaeus-William-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Pecora-Francesco",
"name": {
"family": "Pecora",
"given": "F."
},
"orcid": "0000-0003-4168-590X"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Shen-Ming-Hsueh",
"name": {
"family": "Shen",
"given": "M. M."
},
"orcid": "0000-0002-3093-458X"
},
{
"id": "Braga-Carlos-Roberto",
"name": {
"family": "Braga",
"given": "C. R."
},
"orcid": "0000-0003-1485-9564"
},
{
"id": "Mostafavi-Parisa-S",
"name": {
"family": "Mostafavi",
"given": "P. S."
},
"orcid": "0000-0002-3808-3580"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
}
]
},
"title": "Parker Solar Probe Encounters the Leg of a Coronal Mass Ejection at 14 Solar Radii",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "We gratefully thank everyone that helped make the IS\u2299IS instrument suite and PSP mission possible. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois. Parker Solar Probe was designed, built, and is operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. C.R.B. acknowledges the support from the NASA STEREO/SECCHI (NNG17PP27I) program. The Wide-Field Imager for Parker Solar Probe (WISPR) instrument was designed, built, and is now operated by the US Naval Research Laboratory in collaboration with Johns Hopkins University/Applied Physics Laboratory, California Institute of Technology/Jet Propulsion Laboratory, University of Gottingen, Germany, Centre Spatiale de Liege, Belgium and University of Toulouse/Research Institute in Astrophysics and Planetology. The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) was produced by an international consortium of the Naval Research Laboratory (USA), Lockheed Martin Solar and Astrophysics Lab (USA), NASA Goddard Space Flight Center (USA), Rutherford Appleton Laboratory (UK), University of Birmingham (UK), Max Planck Institute for Solar System Research (Germany), Centre Spatiale de Li\u00e9ge (Belgium), Institut d'Optique Theorique et Appliqu\u00e9e (France), and Institut d'Astrophysique Spatiale (France). STEREO/SECCHI data are available for download at https://secchi.nrl.navy.mil/. SOHO is a project of international cooperation between ESA and NASA. LASCO was constructed by a consortium of institutions: the Naval Research Laboratory (Washington, DC, USA), the Max-Planck-Institut fur Aeronomie (Katlenburg-Lindau, Germany), the Laboratoire d'Astronomie Spatiale (Marseille, France), and the University of Birmingham (Birmingham, UK).",
"abstract": "We use Parker Solar Probe (PSP) observations to report the first direct measurements of the particle and field environments while crossing the leg of a coronal mass ejection (CME) very close to the Sun (\u223c14 Rs). An analysis that combines imaging from 1 au and\u00a0PSP with a CME model, predicts an encounter time and duration that correspond to an unusual, complete dropout in low-energy solar energetic ions from H\u2013Fe, observed by the Integrated Science Investigation of the Sun (IS\u2299IS). The surrounding regions are populated with low-intensity protons and heavy ions from 10s to 100 keV, typical of some quiet times close in to the Sun. In contrast, the magnetic field and solar wind plasma show no similarly abrupt changes at the boundaries of the dropout. Together, the IS\u2299IS energetic particle observations, combined with remote sensing of the CME and a dearth of other \"typical\" CME signatures, indicate that this CME leg is significantly different from the magnetic and plasma structure normally assumed for CMEs near the Sun and observed in interplanetary CMEs farther out in the solar wind. The dropout in low-energy energetic ions may be due to the cooling of suprathermal ions at the base of the CME leg flux tube, owing to the rapid outward expansion during the release of the CME.",
"date": "2023-02-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "943",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 71",
"id_number": "CaltechAUTHORS:20230215-30605800.8",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230215-30605800.8",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "NNG17PP27I"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acab5e",
"pub_year": "2023",
"author_list": "McComas, D. J.; Sharma, T.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tjs7d-sf521",
"eprint_id": 119423,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:58:26",
"lastmod": "2026-03-27 20:36:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Capitanio-Fiamma",
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Gnarini",
"given": "Andrea"
},
"orcid": "0000-0002-0642-1135"
},
{
"name": {
"family": "Ursini",
"given": "Francesco"
},
"orcid": "0000-0001-9442-7897"
},
{
"name": {
"family": "Ferrigno",
"given": "Carlo"
},
"orcid": "0000-0003-1429-1059"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Cocchi",
"given": "Massimo"
},
"orcid": "0000-0002-5817-3129"
},
{
"name": {
"family": "Mikusincova",
"given": "Romana"
},
"orcid": "0000-0001-7374-843X"
},
{
"name": {
"family": "Farinelli",
"given": "Ruben"
},
"orcid": "0000-0003-2212-367X"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Kajava",
"given": "Jari J. E."
},
"orcid": "0000-0002-3010-8333"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Sanchez-Fernandez",
"given": "Celia"
},
"orcid": "0000-0002-0778-6048"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Polarization Properties of the Weakly Magnetized Neutron Star X-Ray Binary GS 1826-238 in the High Soft State",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.\n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy.\n\nThis research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC). This work made use of the MAXI light curves, publicly available at http://maxi.riken.jp/top/slist.html. INTEGRAL is an ESA project with instruments and a science data center funded by ESA member states (especially the PI countries: Denmark, France, Germany, Italy, Switzerland, and Spain) and with the participation of Russia and the USA. We thank Keith Gendreau, Craig Markwardt, and the NICER SOC for granting and performing the NICER observations of the source and helping with data reduction.\n\nJ.P. and S.S.T. acknowledge support from Russian Science Foundation grant 20-12-00364 and Academy of Finland travel grants 349144, 349373, and 349906. J.P. and J.J.E.K. were supported by Academy of Finland grant 333112. \n\nFacilities: IXPE - , Swift (XRT and UVOT) - , INTEGRAL. - \n\nSoftware: Stingray (Huppenkothen et al. 2019a, 2019b), xspec (Arnaud 1996), ixpeobssim (Baldini et al. 2022), monk (Zhang et al. 2019).\n\nPublished - Capitanio_2023_ApJ_943_129.pdf
",
"abstract": "The launch of the Imaging X-ray Polarimetry Explorer (IXPE) on 2021 December 9 has opened a new window in X-ray astronomy. We report here the results of the first IXPE observation of a weakly magnetized neutron star, GS 1826\u2212238, performed on 2022 March 29\u201331 when the source was in a high soft state. An upper limit (99.73% confidence level) of 1.3% for the linear polarization degree is obtained over the IXPE 2\u20138 keV energy range. Coordinated INTEGRAL and NICER observations were carried out simultaneously with IXPE. The spectral parameters obtained from the fits to the broadband spectrum were used as inputs for Monte Carlo simulations considering different possible geometries of the X-ray emitting region. Comparing the IXPE upper limit with these simulations, we can put constraints on the geometry and inclination angle of GS 1826\u2013238.",
"date": "2023-02-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "943",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 129",
"id_number": "CaltechAUTHORS:20230221-19480300.56",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-19480300.56",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Russian Science Foundation",
"grant_number": "20-12-00364"
},
{
"agency": "Academy of Finland",
"grant_number": "349144"
},
{
"agency": "Academy of Finland",
"grant_number": "349373"
},
{
"agency": "Academy of Finland",
"grant_number": "349906"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acae88",
"primary_object": {
"basename": "Capitanio_2023_ApJ_943_129.pdf",
"url": "https://authors.library.caltech.edu/records/tjs7d-sf521/files/Capitanio_2023_ApJ_943_129.pdf"
},
"pub_year": "2023",
"author_list": "Capitanio, Fiamma; Fabiani, Sergio; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8k6g1-rdm71",
"eprint_id": 119397,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:58:15",
"lastmod": "2026-03-27 20:07:37",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cheng-Lei",
"name": {
"family": "Cheng",
"given": "Lei"
},
"orcid": "0000-0002-3824-5172"
},
{
"id": "Zhang-Ming",
"name": {
"family": "Zhang",
"given": "Ming"
},
"orcid": "0000-0003-3529-8743"
},
{
"id": "Lario-David",
"name": {
"family": "Lario",
"given": "David"
},
"orcid": "0000-0002-3176-8704"
},
{
"id": "Balmaceda-Laura-A",
"name": {
"family": "Balmaceda",
"given": "Laura A."
},
"orcid": "0000-0003-1162-5498"
},
{
"id": "Kwon-Ryun-Young",
"name": {
"family": "Kwon",
"given": "Ryun Young"
},
"orcid": "0000-0002-2106-9168"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina"
},
"orcid": "0000-0002-0978-8127"
}
]
},
"title": "Simulation of the Solar Energetic Particle Event on 2020 May 29 Observed by Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nM.Z. acknowledges support from NASA Grants 80NSSC19K1254, 80NSSC21K0004, 80NSSC20K0098, and 80NSSC20K0086. L.A.B. acknowledges support from NASA grant 80NSSC19K1235. D.L. acknowledges support from NASA Living with a Star (LWS) programs NNH17ZDA001N-LWS and NNH19ZDA001N-LWS, the Goddard Space Flight Center Internal Scientist Funding Model (competitive work package) program and the Heliophysics Innovation Fund (HIF) program. This CME catalog is generated and maintained at the CDAW Data Center by NASA and The Catholic University of America in cooperation with the Naval Research Laboratory. SOHO is a project of international cooperation between ESA and NASA. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program. The data from the observation are downloaded from http://spdf.gsfc.nasa.gov. The computation facility used to run the simulations in the paper was supported by the National Science Foundation under grant No. CNS 2016818.\n\nPublished - Cheng_2023_ApJ_943_134.pdf
",
"abstract": "This paper presents a stochastic three-dimensional focused transport simulation of solar energetic particles (SEPs) produced by a data-driven coronal mass ejection (CME) shock propagating through a data-driven model of coronal and heliospheric magnetic fields. The injection of SEPs at the CME shock is treated using diffusive shock acceleration of post-shock suprathermal solar wind ions. A time-backward stochastic simulation is employed to solve the transport equation to obtain the SEP time\u2013intensity profile at any location, energy, and pitch angle. The model is applied to a SEP event on 2020 May 29, observed by STEREO-A close to \u223c1 au and by Parker Solar Probe (PSP) when it was about 0.33 au away from the Sun. The SEP event was associated with a very slow CME with a plane-of-sky speed of 337 km s\u207b\u00b9 at a height below 6 R_S as reported in the SOHO/LASCO CME catalog. We compute the time profiles of particle flux at PSP and STEREO-A locations, and estimate both the spectral index of the proton energy spectrum for energies between \u223c2 and 16 MeV and the equivalent path length of the\nmagnetic field lines experienced by the first arriving SEPs. We find that the simulation results are well correlated with observations. The SEP event could be explained by the acceleration of particles by a weak CME shock in the low solar corona that is not magnetically connected to the observers.",
"date": "2023-02-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "943",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 134",
"id_number": "CaltechAUTHORS:20230221-19411400.40",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-19411400.40",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K1254"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0004"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0098"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0086"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1235"
},
{
"agency": "NASA",
"grant_number": "NNH17ZDA001N-LWS"
},
{
"agency": "NASA",
"grant_number": "NNH19ZDA001N-LWS"
},
{
"agency": "Goddard Space Flight Center"
},
{
"agency": "NSF",
"grant_number": "CNS-2016818"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/acac21",
"primary_object": {
"basename": "Cheng_2023_ApJ_943_134.pdf",
"url": "https://authors.library.caltech.edu/records/8k6g1-rdm71/files/Cheng_2023_ApJ_943_134.pdf"
},
"pub_year": "2023",
"author_list": "Cheng, Lei; Zhang, Ming; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ejrrd-2sd18",
"eprint_id": 119238,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:51:20",
"lastmod": "2025-11-22 04:08:58",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mitchell-John-Grant",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Eddy-T-J",
"name": {
"family": "Eddy",
"given": "T. J."
}
},
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Shen-Ming-Hsueh",
"name": {
"family": "Shen",
"given": "M. M."
},
"orcid": "0000-0002-3093-458X"
},
{
"id": "de-Nolfo-Georgia-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
}
]
},
"title": "A Living Catalog of Parker Solar Probe IS\u2299IS Energetic Particle Enhancements",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "We wish to acknowledge the support of NASA's Parker Solar Probe grant No. NNN06AA01C. We thank the Parker Solar Probe IS\u2299IS team, including the engineers, technicians, administrators, and scientists, who developed the instruments used in this study. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). J.G.M.'s research was supported by an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by ORAU through a contract with NASA. Sunspot number data were provided by the NOAA Space Weather Prediction Center (https://www.swpc.noaa.gov/products/solar-cycle-progression).",
"abstract": "Energetic charged particles are pervasive throughout the heliosphere with contributions from solar energetic particle events, stream and corotating interaction regions, galactic cosmic rays, anomalous cosmic rays, and suprathermal ions. The Integrated Science Investigation of the Sun (IS\u2299IS) on board the Parker Solar Probe is a suite of energetic particle detectors covering the energy range \u223c20 keV\u2013200 MeV nuc\u207b\u00b9. IS\u2299IS measures energetic particles closer to the Sun than any instrument suite in history, providing a singular view of the energetic particle population in a previously unexplored region. To enable the global research community to efficiently use IS\u2299IS data, we have developed an online living catalog of energetic particle enhancements observed by the IS\u2299IS instruments. Event identification methodology, information on accessing the catalog, highlights of several events, and a summary of the overall trends are presented. Also included is a summary Event Catalog showing many of the key event parameters for IS\u2299IS events to the time of writing.",
"date": "2023-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "264",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 31",
"id_number": "CaltechAUTHORS:20230213-466022900.7",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230213-466022900.7",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/aca4c8",
"pub_year": "2023",
"author_list": "Mitchell, J. G.; Cohen, C. M. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/d17f5-exn11",
"eprint_id": 121355,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:57:04",
"lastmod": "2025-11-22 02:28:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kennicutt-Robert-C-Jr",
"name": {
"family": "Kennicutt",
"given": "Robert"
},
"orcid": "0000-0001-5448-1821"
}
]
},
"title": "Commentary: Astronomy from space after the JWST",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "General Physics and Astronomy",
"note": "\u00a9 2023 American Institute of Physics.",
"abstract": "Last year the James Webb Space Telescope (JWST) trained its sights on the distant universe and began returning stunning images in IR light that captured the imagination of the public around the world. The JWST has only just begun its exploration of the universe, yet astronomers are already looking to the future. \n\nEvery 10 years, panels of experts convened by the National Academies create a survey in astronomy and astrophysics to assess scientific frontiers and plan the capabilities that will keep advancing humankind's understanding of the cosmos. The JWST, originally called the Next Generation Space Telescope, was recommended as the top-priority large strategic mission in the 2000 decadal survey, and given its technical ambition and scale, it took more than two decades to be realized. But it was also conceived as costing less than 10% of the eventual price tag, in part because of wishful thinking by NASA and the scientific community and in part because the project began full-scale development before it was ready. \n\nThe 2010 decadal survey gave the highest priority for a large space mission to the Nancy Grace Roman Space Telescope, then known as the Wide-Field Infrared Survey Telescope, an observatory that will image large swaths of the sky in IR light to make three-dimensional cosmic maps of many millions of galaxies, elucidate the nature of the mysterious dark matter and dark energy, search for and image exoplanets, and explore many other topics in IR astrophysics. Roman is scheduled for launch in 2027, some 17 years after it was recommended as a priority. That delay was a result of funding issues directly related to the cost overruns on the JWST. Like the JWST, Roman was chosen to address the big, outstanding scientific questions identified at the time. But the delays bring with them costs in both taxpayer dollars and scientific opportunities. \n\nThe most recent astronomy and astrophysics survey, Astro2020 (for which the two of us served as committee cochairs), considered how to accomplish its charge to chart a course for the future of space astrophysics. In previous surveys, the committees have provided a rank-ordered list of concepts for large space missions, and in the decade that followed, NASA began development of the top project on the list as its next priority. Astro2020, however, took a different course.",
"date": "2023-02",
"date_type": "published",
"publication": "Physics Today",
"volume": "76",
"number": "2",
"publisher": "American Institute of Physics",
"pagerange": "10-11",
"id_number": "CaltechAUTHORS:20230509-291707400.4",
"issn": "0031-9228",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230509-291707400.4",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1063/pt.3.5167",
"pub_year": "2023",
"author_list": "Harrison, Fiona and Kennicutt, Robert"
},
{
"id": "https://authors.library.caltech.edu/records/0ksy3-8c779",
"eprint_id": 119562,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:52:57",
"lastmod": "2026-03-27 18:44:48",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Raouafi-Nour-E",
"name": {
"family": "Raouafi",
"given": "N. E."
},
"orcid": "0000-0003-2409-3742"
},
{
"name": {
"family": "Matteini",
"given": "L."
},
"orcid": "0000-0002-6276-7771"
},
{
"name": {
"family": "Squire",
"given": "J."
},
"orcid": "0000-0001-8479-962X"
},
{
"name": {
"family": "Badman",
"given": "S. T."
},
"orcid": "0000-0002-6145-436X"
},
{
"name": {
"family": "Velli",
"given": "M."
},
"orcid": "0000-0002-2381-3106"
},
{
"name": {
"family": "Klein",
"given": "K. G."
},
"orcid": "0000-0001-6038-1923"
},
{
"name": {
"family": "Chen",
"given": "C. H. K."
},
"orcid": "0000-0003-4529-3620"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "Szabo",
"given": "A."
},
"orcid": "0000-0003-3255-9071"
},
{
"name": {
"family": "Linton",
"given": "M."
},
"orcid": "0000-0002-4459-7510"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Bruno",
"given": "R."
},
"orcid": "0000-0002-2152-0115"
},
{
"name": {
"family": "Decker",
"given": "R. B."
},
"orcid": "0000-0002-0655-9863"
},
{
"name": {
"family": "Akhavan-Tafti",
"given": "M."
},
"orcid": "0000-0003-3721-2114"
},
{
"name": {
"family": "Agapitov",
"given": "O. V."
},
"orcid": "0000-0001-6427-1596"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Bandyopadhyay",
"given": "R."
},
"orcid": "0000-0002-6962-0959"
},
{
"name": {
"family": "Battams",
"given": "K."
},
"orcid": "0000-0002-8692-6925"
},
{
"name": {
"family": "Ber\u010di\u010d",
"given": "L."
},
"orcid": "0000-0002-6075-1813"
},
{
"name": {
"family": "Bourouaine",
"given": "S."
},
"orcid": "0000-0002-2358-6628"
},
{
"name": {
"family": "Bowen",
"given": "T. A."
},
"orcid": "0000-0002-4625-3332"
},
{
"name": {
"family": "Cattell",
"given": "C."
},
"orcid": "0000-0002-3805-320X"
},
{
"name": {
"family": "Chandran",
"given": "B. D. G."
},
"orcid": "0000-0003-4177-3328"
},
{
"name": {
"family": "Chhiber",
"given": "R."
},
"orcid": "0000-0002-7174-6948"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "D'Amicis",
"given": "R."
},
"orcid": "0000-0003-2647-117X"
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Hess",
"given": "P."
},
"orcid": "0000-0003-1377-6353"
},
{
"name": {
"family": "Howard",
"given": "R. A."
},
"orcid": "0000-0001-9027-8249"
},
{
"name": {
"family": "Horbury",
"given": "T. S."
},
"orcid": "0000-0002-7572-4690"
},
{
"name": {
"family": "Jagarlamudi",
"given": "V. K."
},
"orcid": "0000-0001-6287-6479"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Kinnison",
"given": "J."
}
},
{
"name": {
"family": "Laker",
"given": "R."
},
"orcid": "0000-0002-6577-5515"
},
{
"id": "Liewer-Paulett",
"name": {
"family": "Liewer",
"given": "P."
},
"orcid": "0000-0002-5068-4637"
},
{
"name": {
"family": "Malaspina",
"given": "D. M."
},
"orcid": "0000-0003-1191-1558"
},
{
"name": {
"family": "Mann",
"given": "I."
},
"orcid": "0000-0002-2805-3265"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Niembro-Hernandez",
"given": "T."
},
"orcid": "0000-0001-6692-9187"
},
{
"name": {
"family": "Nieves-Chinchilla",
"given": "T."
},
"orcid": "0000-0003-0565-4890"
},
{
"name": {
"family": "Panasenco",
"given": "O."
},
"orcid": "0000-0002-4440-7166"
},
{
"name": {
"family": "Pokorn\u00fd",
"given": "P."
},
"orcid": "0000-0002-5667-9337"
},
{
"name": {
"family": "Pusack",
"given": "A."
},
"orcid": "0000-0002-3081-8597"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Perez",
"given": "J. C."
},
"orcid": "0000-0002-8841-6443"
},
{
"name": {
"family": "Riley",
"given": "P."
},
"orcid": "0000-0002-1859-456X"
},
{
"name": {
"family": "Rouillard",
"given": "A. P."
},
"orcid": "0000-0003-4039-5767"
},
{
"name": {
"family": "Shi",
"given": "C."
},
"orcid": "0000-0002-2582-7085"
},
{
"name": {
"family": "Stenborg",
"given": "G."
},
"orcid": "0000-0001-8480-947X"
},
{
"name": {
"family": "Tenerani",
"given": "A."
},
"orcid": "0000-0003-2880-6084"
},
{
"name": {
"family": "Verniero",
"given": "J. L."
},
"orcid": "0000-0003-1138-652X"
},
{
"name": {
"family": "Viall",
"given": "N."
},
"orcid": "0000-0003-1692-1704"
},
{
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
},
{
"name": {
"family": "Wood",
"given": "B. E."
},
"orcid": "0000-0002-4998-0893"
},
{
"name": {
"family": "Woodham",
"given": "L. D."
},
"orcid": "0000-0003-2845-4250"
},
{
"name": {
"family": "Woolley",
"given": "T."
},
"orcid": "0000-0002-9202-619X"
}
]
},
"title": "Parker Solar Probe: Four Years of Discoveries at Solar Cycle Minimum",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nParker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission.\n\nThe FIELDS instrument suite was designed and built and is operated by a consortium of institutions including the University of California, Berkeley, University of Minnesota, University of Colorado, Boulder, NASA/GSFC, CNRS/LPC2E, University of New Hampshire, University of Maryland, UCLA, IFRU, Observatoire de Meudon, Imperial College, London and Queen Mary University London.\n\nThe SWEAP Investigation is a multi-institution project led by the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts. Other members of the SWEAP team come from the University of Michigan, University of California, Berkeley Space Sciences Laboratory, The NASA Marshall Space Flight Center, The University of Alabama Huntsville, the Massachusetts Institute of Technology, Los Alamos National Laboratory, Draper Laboratory, JHU Applied Physics Laboratory, and NASA Goddard Space Flight Center. \n\nThe Integrated Science Investigation of the Sun (IS\u2299IS) Investigation is a multi-institution project led by Princeton University with contributions from JHU Applied Physics Laboratory, Caltech, GSFC, JPL, SwRI, University of New Hampshire, University of Delaware, and University of Arizona. \n\nThe Wide-Field Imager for Parker Solar Probe (WISPR) instrument was designed, built, and is now operated by the U.S. Naval Research Laboratory in collaboration with JHU Applied Physics Laboratory, California Institute of Technology/Jet Propulsion Laboratory, University of Gottingen, Germany, Centre Spatiale de Liege, Belgium and University of Toulouse/Research Institute in Astrophysics and Planetology. \n\nO.V.A. was supported by NASA grants 80NNSC19K0848, 80NSSC22K0417, 80NSSC21K1770, and NSF grant 1914670. S.B. is supported by NASA grants 80NSSC21K0012 and Parker Solar Probe as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). C.H.K.C. is supported by UKRI Future Leaders Fellowship MR/W007657/1 and STFC Consolidated Grant ST/T00018X/1. R.C. was supported by NASA grants 80NSSC18K1210, 80NSSC18K1648, and 80NSSC21K1765. K.G.K. was supported by NASA grant 80NSSC19K0912. I.M. is supported by the Research Council of Norway (grant number 262941). Support for J.S. was provided by Rutherford Discovery Fellowship RDF-U001804, which is managed through the Royal Society Te Ap\u0101rangi. J.R.S, P.P., and D.M.M. acknowledge the Parker Solar Probe Guest Investigator Program, grant 80NSSC21K1764. M.A.T. was supported by NASA contract NNN06AA01C and grants 80NSSC20K1847, 80NSSC20K1014, and 80NSSC21K1662. \n\nThere are no conflicts of interest (financial or non-financial) for any of the co-authors of this article.\n\nPublished - s11214-023-00952-4.pdf
",
"abstract": "Launched on 12 Aug. 2018, NASA's Parker Solar Probe had completed 13 of its scheduled 24 orbits around the Sun by Nov. 2022. The mission's primary science goal is to determine the structure and dynamics of the Sun's coronal magnetic field, understand how the solar corona and wind are heated and accelerated, and determine what processes accelerate energetic particles. Parker Solar Probe returned a treasure trove of science data that far exceeded quality, significance, and quantity expectations, leading to a significant number of discoveries reported in nearly 700 peer-reviewed publications. The first four years of the 7-year primary mission duration have been mostly during solar minimum conditions with few major solar events. Starting with orbit 8 (i.e., 28 Apr. 2021), Parker flew through the magnetically dominated corona, i.e., sub-Alfv\u00e9nic solar wind, which is one of the mission's primary objectives. In this paper, we present an overview of the scientific advances made mainly during the first four years of the Parker Solar Probe mission, which go well beyond the three science objectives that are: (1) Trace the flow of energy that heats and accelerates the solar corona and solar wind; (2) Determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind; and (3) Explore mechanisms that accelerate and transport energetic particles.",
"date": "2023-02",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "219",
"number": "1",
"publisher": "Springer",
"pagerange": "Art. No. 8",
"id_number": "CaltechAUTHORS:20230227-88449200.50",
"issn": "0038-6308",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230227-88449200.50",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NNSC19K0848"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0417"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1770"
},
{
"agency": "NSF",
"grant_number": "AGS-1914670"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0012"
},
{
"agency": "UK Research and Innovation",
"grant_number": "MR/W007657/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T00018X/1"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1210"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1648"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1765"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0912"
},
{
"agency": "Research Council of Norway",
"grant_number": "262941"
},
{
"agency": "Royal Society Te Ap\u0101rangi",
"grant_number": "RDF-U001804"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1764"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1847"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1014"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1662"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1007/s11214-023-00952-4",
"primary_object": {
"basename": "s11214-023-00952-4.pdf",
"url": "https://authors.library.caltech.edu/records/0ksy3-8c779/files/s11214-023-00952-4.pdf"
},
"pub_year": "2023",
"author_list": "Raouafi, N. E.; Matteini, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/eegpe-hmh46",
"eprint_id": 119612,
"eprint_status": "archive",
"datestamp": "2023-08-20 09:01:21",
"lastmod": "2025-11-22 02:29:45",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Roach-Brandon-M",
"name": {
"family": "Roach",
"given": "Brandon M."
},
"orcid": "0000-0003-3841-6290"
},
{
"id": "Rossland-Steven",
"name": {
"family": "Rossland",
"given": "Steven"
},
"orcid": "0000-0001-6304-1035"
},
{
"id": "Ng-Kenny-C-Y",
"name": {
"family": "Ng",
"given": "Kenny C.\u2009Y."
},
"orcid": "0000-0001-8016-2170"
},
{
"id": "Perez-Kerstin-M",
"name": {
"family": "Perez",
"given": "Kerstin"
},
"orcid": "0000-0002-6404-4737"
},
{
"id": "Beacom-John-F",
"name": {
"family": "Beacom",
"given": "John F."
},
"orcid": "0000-0002-0005-2631"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Horiuchi-Shunsaku",
"name": {
"family": "Horiuchi",
"given": "Shunsaku"
},
"orcid": "0000-0001-6142-6556"
},
{
"id": "Krivonos-Roman-A",
"name": {
"family": "Krivonos",
"given": "Roman"
},
"orcid": "0000-0003-2737-5673"
},
{
"id": "Wik-Daniel-R",
"name": {
"family": "Wik",
"given": "Daniel R."
},
"orcid": "0000-0001-9110-2245"
}
]
},
"title": "Long-exposure NuSTAR constraints on decaying dark matter in the Galactic halo",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2023 American Physical Society. \n\nWe are grateful to the NuSTAR team for the excellent performance of the observatory and their assistance with data processing. We also thank Alexey Boyarsky, Josh Foster, Nick Rodd, Field Rogers, Mengjiao Xiao, and the anonymous reviewer for helpful comments and discussions. B.\u2009M.\u2009R. and K.\u2009P. thank Paul Acosta, Gabriel Collin, and the MIT Laboratory for Nuclear Science for computing support. B.\u2009M.\u2009R. and K.\u2009P. were supported by the Cottrell Scholar Award, Research Corporation for Science Advancement (RCSA), ID No. 25928. S.\u2009R. and D.\u2009R.\u2009W. were supported by NASA Grant No. 80NSSC18K0686. K.\u2009C.\u2009Y.\u2009N. was supported by the Research Grants Council (RGC) of HKSAR, Project No. 24302721. J.\u2009F.\u2009B. was supported by U.S. National Science Foundation (NSF) Grant No. PHY-2012955. B.\u2009W.\u2009G. was supported by NASA Contract No. NNG08FD60C.\u2009S.\u2009H. was supported by the U.S. Department of Energy Office of Science under Award No. DE-SC0020262, NSF Grants No. AST-1908960 and No. PHY-1914409, JSPS KAKENHI Grant No. JP22K03630, and the World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan. R.\u2009K. was supported by Russian Science Foundation Grant No. 22-12-00271. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC.\n\nPublished - PhysRevD.107.023009.pdf
",
"abstract": "We present two complementary NuSTAR x-ray searches for keV-scale dark matter decaying to monoenergetic photons in the Milky Way halo. In the first, we utilize the known intensity pattern of unfocused stray light across the detector planes\u2014the dominant source of photons from diffuse sources\u2014to separate astrophysical emission from internal instrument backgrounds using ~7-Ms/detector deep blank-sky exposures. In the second, we present an updated parametric model of the full NuSTAR instrument background, allowing us to leverage the statistical power of an independent ~20-Ms/detector stacked exposures spread across the sky. Finding no evidence of anomalous x-ray lines using either method, we set limits on the active-sterile mixing angle sin\u00b2 (2\u03b8) for sterile-neutrino masses 6\u201340 keV. The first key result is that we strongly disfavor a ~7-keV sterile neutrino decaying into a 3.5-keV photon. The second is that we derive leading limits on sterile neutrinos with masses ~15-18 keV and ~25-40 KeV, reaching or extending below the big bang nucleosynthesis limit. In combination with previous results, the parameter space for the neutrino minimal standard model is now nearly closed.",
"date": "2023-01-15",
"date_type": "published",
"publication": "Physical Review D",
"volume": "107",
"number": "2",
"publisher": "American Physical Society",
"pagerange": "Art. No. 023009",
"id_number": "CaltechAUTHORS:20230301-701033500.15",
"issn": "2470-0010",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230301-701033500.15",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Cottrell Scholar of Research Corporation",
"grant_number": "25928"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0686"
},
{
"agency": "Research Grants Council of Hong Kong",
"grant_number": "24302721"
},
{
"agency": "NSF",
"grant_number": "PHY-2012955"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-SC0020262"
},
{
"agency": "NSF",
"grant_number": "AST-1908960"
},
{
"agency": "NSF",
"grant_number": "PHY-1914409"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP22K03630"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)"
},
{
"agency": "Russian Science Foundation",
"grant_number": "22-12-00271"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1103/physrevd.107.023009",
"primary_object": {
"basename": "PhysRevD.107.023009.pdf",
"url": "https://authors.library.caltech.edu/records/eegpe-hmh46/files/PhysRevD.107.023009.pdf"
},
"pub_year": "2023",
"author_list": "Roach, Brandon M.; Rossland, Steven; et al."
},
{
"id": "https://authors.library.caltech.edu/records/npvmf-f0y03",
"eprint_id": 119494,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:40:16",
"lastmod": "2026-03-27 20:20:24",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"name": {
"family": "Kakkad",
"given": "Darshan"
},
"orcid": "0000-0002-2603-2639"
},
{
"name": {
"family": "Casey-Clyde",
"given": "J. Andrew"
},
"orcid": "0000-0002-5557-4007"
},
{
"name": {
"family": "Kawamuro",
"given": "Taiki"
},
"orcid": "0000-0002-6808-2052"
},
{
"name": {
"family": "Williams",
"given": "Jonathan"
},
"orcid": "0000-0002-0441-3502"
},
{
"name": {
"family": "Foord",
"given": "Adi"
},
"orcid": "0000-0002-1616-1701"
},
{
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Barcos-Munoz",
"given": "Loreto"
},
"orcid": "0000-0003-0057-8892"
},
{
"name": {
"family": "Blecha",
"given": "Laura"
},
"orcid": "0000-0002-2183-1087"
},
{
"id": "Connor-Thomas",
"name": {
"family": "Connor",
"given": "Thomas"
},
"orcid": "0000-0002-7898-7664"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Liu",
"given": "Tingting"
},
"orcid": "0000-0001-5766-4287"
},
{
"name": {
"family": "Magno",
"given": "Macon"
},
"orcid": "0000-0002-1292-1451"
},
{
"name": {
"family": "Mingarelli",
"given": "Chiara M. F."
},
"orcid": "0000-0002-4307-1322"
},
{
"name": {
"family": "Muller-Sanchez",
"given": "Francisco"
},
"orcid": "0000-0002-2713-0628"
},
{
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"name": {
"family": "Shimizu",
"given": "T. Taro"
},
"orcid": "0000-0002-2125-4670"
},
{
"name": {
"family": "Smith",
"given": "Krista Lynne"
},
"orcid": "0000-0001-5785-7038"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Tello",
"given": "Miguel Parra"
},
"orcid": "0000-0001-5649-7798"
},
{
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "UGC 4211: A Confirmed Dual Active Galactic Nucleus in the Local Universe at 230 pc Nuclear Separation",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nWe thank the anonymous referee for very useful comments and suggestions to improve the manuscript. The authors would like to express their appreciation for useful software discussions with Roland Bacon and Yao Yao as well as the observation planning with ESO astronomer Michael Hilker who supported multiple attempts to observe this object. We acknowledge support from: NASA through ADAP award NNH16CT03C (M.K.), ANID through Millennium Science Initiative Program-NCN19_058 (E.T.), and ICN12_009 (F.E.B.), CATA-BASAL - ACE210002 (E.T., F.E.B.), and FB210003 (E.T., F.E.B., C.R.), FONDECYT Regular-1190818 (E.T., F.E.B.), and 1200495 (F.E.B., E.T.), and Fondecyt Iniciacion 11190831 (C.R.), NSF grants PHY-2020265 (T.L., C.M.F.M.) and AST-2106552 (C.M.F.M.), NSF award AST-1909933 and Cottrell Scholar Award 27553 (L.B.), ADAP award 80NSSC19K1096 (F.M.-S.), the European Union's Horizon 2020 research and innovation program (950533), and Israel Science Foundation grant 1849/19 (B.T.), Project No. 2022-1-830-06 from the Korea Astronomy and Space Science Institute (K.O.) and the National Research Foundation of Korea (NRF-2020R1C1C1005462), JSPS KAKENHI grant JP20K14529 and the Special Postdoctoral Researchers Program at RIKEN (T.K.), and the hospitality of NRAO/NAASC during his sabbatical leave (E.T.). The Flatiron Institute is supported by the Simons Foundation. \n\nFacilities: ALMA - Atacama Large Millimeter Array, CXO - , HST (STIS - , ACS - , WFC3) - , Keck:I (OSIRIS) - , Keck:II (NIRC2) - , NuSTAR - , Swift (BAT and XRT) - , VLA - , VLT:Yepun. - \n\nSoftware: APLpy (Robitaille & Bressert 2012), astropy (Collaboration et al. 2013), Matplotlib (Hunter 2007), jupyter notebook, Numpy (van der Walt et al. 2011), MPDAF (Bacon et al. 2016), pPXF (Cappellari 2017), PySpecKit (Ginsburg & Mirocha 2011), vorbin (Cappellari & Copin 2003).\n\nPublished - Koss_2023_ApJL_942_L24.pdf
",
"abstract": "We present multiwavelength high-spatial resolution (\u223c0\".1, 70 pc) observations of UGC 4211 at z = 0.03474, a late-stage major galaxy merger at the closest nuclear separation yet found in near-IR imaging (0\".32, \u223c230 pc projected separation). Using Hubble Space Telescope/Space Telescope Imaging Spectrograph, Very Large Telescope/MUSE+AO, Keck/OSIRIS+AO spectroscopy, and the Atacama Large Millimeter/submillimeter Array (ALMA) observations, we show that the spatial distribution, optical and near-infrared emission lines, and millimeter continuum emission are all consistent with both nuclei being powered by accreting supermassive black holes (SMBHs). Our data, combined with common black hole mass prescriptions, suggest that both SMBHs have similar masses, log(M_(BH)/M_\u2299) \u223c 8.1 (south) and log(M_(BH)/M_\u2299) \u223c 8.3 (north), respectively. The projected separation of 230 pc (\u223c6\u00d7 the black hole sphere of influence) represents the closest-separation dual active galactic nuclei (AGN) studied to date with multiwavelength resolved spectroscopy and shows the potential of nuclear (<50 pc) continuum observations with ALMA to discover hidden growing SMBH pairs. While the exact occurrence rate of close-separation dual AGN is not yet known, it may be surprisingly high, given that UGC 4211 was found within a small, volume-limited sample of nearby hard X-ray detected AGN. Observations of dual SMBH binaries in the subkiloparsec regime at the final stages of dynamical friction provide important constraints for future gravitational wave observatories.",
"date": "2023-01-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "942",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L24",
"id_number": "CaltechAUTHORS:20230223-184464800.10",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230223-184464800.10",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ICN12_009"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "NSF",
"grant_number": "PHY-2020265"
},
{
"agency": "NSF",
"grant_number": "AST-2106552"
},
{
"agency": "NSF",
"grant_number": "AST-1909933"
},
{
"agency": "Cottrell Scholar of Research Corporation",
"grant_number": "27553"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1096"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "Korea Astronomy and Space Science Institute (KASI)",
"grant_number": "2022-1-830-06"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP20K14529"
},
{
"agency": "RIKEN"
},
{
"agency": "Simons Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/aca8f0",
"primary_object": {
"basename": "Koss_2023_ApJL_942_L24.pdf",
"url": "https://authors.library.caltech.edu/records/npvmf-f0y03/files/Koss_2023_ApJL_942_L24.pdf"
},
"pub_year": "2023",
"author_list": "Koss, Michael J.; Treister, Ezequiel; et al."
},
{
"id": "https://authors.library.caltech.edu/records/sm7k9-1qe15",
"eprint_id": 120046,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:40:33",
"lastmod": "2025-11-22 03:42:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Middei-Riccardo",
"name": {
"family": "Middei",
"given": "Riccardo"
},
"orcid": "0000-0001-9815-9092"
},
{
"id": "Liodakis-Ioannis",
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"id": "Perri-Matteo",
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"id": "Puccetti-Simonetta",
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"id": "Cavazzuti-Elisabetta",
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"id": "Di-Gesu-Laura",
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"id": "Ehlert-Steven-R",
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-1111-4292"
},
{
"id": "Madejski-Grzegorz",
"name": {
"family": "Madejski",
"given": "Grzegorz"
}
},
{
"id": "Marscher-Alan-P",
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"id": "Marshall-Herman-L",
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"id": "Muleri-Fabio",
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"id": "Negro-Michela",
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"id": "Jorstad-Svetlana-G",
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"id": "Ag\u00eds-Gonz\u00e1lez-Beatriz",
"name": {
"family": "Ag\u00eds-Gonz\u00e1lez",
"given": "Beatriz"
},
"orcid": "0000-0001-7702-8931"
},
{
"id": "Agudo-Iv\u00e1n",
"name": {
"family": "Agudo",
"given": "Ivan"
},
"orcid": "0000-0002-3777-6182"
},
{
"id": "Bonnoli-Giacomo",
"name": {
"family": "Bonnoli",
"given": "Giacomo"
},
"orcid": "0000-0003-2464-9077"
},
{
"id": "Bernardos-Maria-I",
"name": {
"family": "Bernardos",
"given": "Maria I."
}
},
{
"id": "Casanova-V\u00edctor",
"name": {
"family": "Casanova",
"given": "V\u00edctor"
}
},
{
"id": "Garc\u00eda-Comas-Maya",
"name": {
"family": "Garc\u00eda-Comas",
"given": "Maya"
},
"orcid": "0000-0003-2323-4486"
},
{
"id": "Husillos-C\u00e9sar",
"name": {
"family": "Husillos",
"given": "C\u00e9sar"
},
"orcid": "0000-0001-8286-5443"
},
{
"id": "Marchini-Alessandro",
"name": {
"family": "Marchini",
"given": "Alessandro"
},
"orcid": "0000-0003-3779-6762"
},
{
"id": "Sota-Alfredo",
"name": {
"family": "Sota",
"given": "Alfredo"
},
"orcid": "0000-0002-9404-6952"
},
{
"id": "Kouch-Pouya-M",
"name": {
"family": "Kouch",
"given": "Pouya M."
},
"orcid": "0000-0002-9328-2750"
},
{
"id": "Lindfors-Elina",
"name": {
"family": "Lindfors",
"given": "Elina"
},
"orcid": "0000-0002-9155-6199"
},
{
"id": "Borman-George-A",
"name": {
"family": "Borman",
"given": "George A."
},
"orcid": "0000-0002-7262-6710"
},
{
"id": "Kopatskaya-Evgenia-N",
"name": {
"family": "Kopatskaya",
"given": "Evgenia N."
},
"orcid": "0000-0001-9518-337X"
},
{
"id": "Larionova-E-G",
"name": {
"family": "Larionova",
"given": "Elena G."
},
"orcid": "0000-0002-2471-6500"
},
{
"id": "Morozova-Daria-A",
"name": {
"family": "Morozova",
"given": "Daria A."
},
"orcid": "0000-0002-9407-7804"
},
{
"id": "Savchenko-Sergey-S",
"name": {
"family": "Savchenko",
"given": "Sergey S."
},
"orcid": "0000-0003-4147-3851"
},
{
"id": "Vasilyev-Andrey-A",
"name": {
"family": "Vasilyev",
"given": "Andrey A."
},
"orcid": "0000-0002-8293-0214"
},
{
"id": "Zhovtan-Alexey-V",
"name": {
"family": "Zhovtan",
"given": "Alexey V."
}
},
{
"id": "Casadio-Carolina",
"name": {
"family": "Casadio",
"given": "Carolina"
},
"orcid": "0000-0003-1117-2863"
},
{
"id": "Escudero-Juan",
"name": {
"family": "Escudero",
"given": "Juan"
},
"orcid": "0000-0002-4131-655X"
},
{
"id": "Myserlis-Ioannis",
"name": {
"family": "Myserlis",
"given": "Ioannis"
},
"orcid": "0000-0003-3025-9497"
},
{
"id": "Hales-Antonio",
"name": {
"family": "Hales",
"given": "Antonio"
}
},
{
"id": "Kameno-Seiji",
"name": {
"family": "Kameno",
"given": "Seiji"
},
"orcid": "0000-0002-5158-0063"
},
{
"id": "Kneissl-Ruediger",
"name": {
"family": "Kneissl",
"given": "Ruediger"
},
"orcid": "0000-0002-5580-006X"
},
{
"id": "Messias-Hugo",
"name": {
"family": "Messias",
"given": "Hugo"
},
"orcid": "0000-0002-2985-7994"
},
{
"id": "Nagai-Hiroshi",
"name": {
"family": "Nagai",
"given": "Hiroshi"
},
"orcid": "0000-0003-0292-3645"
},
{
"id": "Blinov-Dmitry",
"name": {
"family": "Blinov",
"given": "Dmitry"
},
"orcid": "0000-0002-8597-6154"
},
{
"id": "Bourbah-Ioakeim-G",
"name": {
"family": "Bourbah",
"given": "Ioakeim G."
},
"orcid": "0000-0002-8597-6154"
},
{
"id": "Kiehlmann-Sebastian",
"name": {
"family": "Kiehlmann",
"given": "Sebastian"
},
"orcid": "0000-0001-6314-9177"
},
{
"id": "Kontopodis-Evangelos",
"name": {
"family": "Kontopodis",
"given": "Evangelos"
}
},
{
"id": "Mandarakas-Nikos",
"name": {
"family": "Mandarakas",
"given": "Nikos"
},
"orcid": "0000-0002-2567-2132"
},
{
"id": "Romanopoulos-Stylianos",
"name": {
"family": "Romanopoulos",
"given": "Stylianos"
},
"orcid": "0000-0002-2897-2448"
},
{
"id": "Skalidis-Raphael",
"name": {
"family": "Skalidis",
"given": "Raphael"
},
"orcid": "0000-0003-2337-0277"
},
{
"id": "Vervelaki-Anna",
"name": {
"family": "Vervelaki",
"given": "Anna"
}
},
{
"id": "Masiero-Joseph-R",
"name": {
"family": "Masiero",
"given": "Joseph R."
},
"orcid": "0000-0003-2638-720X"
},
{
"id": "Mawet-D",
"name": {
"family": "Mawet",
"given": "Dimitri"
},
"orcid": "0000-0002-8895-4735"
},
{
"id": "Millar-Blanchaer-Maxwell-A",
"name": {
"family": "Millar-Blanchaer",
"given": "Maxwell A."
},
"orcid": "0000-0001-6205-9233"
},
{
"id": "Panopoulou-Georgia-V",
"name": {
"family": "Panopoulou",
"given": "Georgia V."
},
"orcid": "0000-0001-7482-5759"
},
{
"id": "Tinyanont-Samaporn",
"name": {
"family": "Tinyanont",
"given": "Samaporn"
},
"orcid": "0000-0002-1481-4676"
},
{
"id": "Berdyugin-Andrei-V",
"name": {
"family": "Berdyugin",
"given": "Andrei V."
},
"orcid": "0000-0002-9353-5164"
},
{
"id": "Kagitani-Masato",
"name": {
"family": "Kagitani",
"given": "Masato"
},
"orcid": "0000-0002-4115-7122"
},
{
"id": "Kravtsov-Vadim",
"name": {
"family": "Kravtsov",
"given": "Vadim"
},
"orcid": "0000-0002-7502-3173"
},
{
"id": "Sakanoi-Takeshi",
"name": {
"family": "Sakanoi",
"given": "Takeshi"
},
"orcid": "0000-0002-7146-9020"
},
{
"id": "Imazawa-Ryo",
"name": {
"family": "Imazawa",
"given": "Ryo"
},
"orcid": "0000-0002-0643-7946"
},
{
"id": "Sasada-Mahito",
"name": {
"family": "Sasada",
"given": "Mahito"
},
"orcid": "0000-0001-5946-9960"
},
{
"id": "Fukazawa-Yasushi",
"name": {
"family": "Fukazawa",
"given": "Yasushi"
},
"orcid": "0000-0002-0921-8837"
},
{
"id": "Kawabata-Koji-S",
"name": {
"family": "Kawabata",
"given": "Koji S."
},
"orcid": "0000-0001-6099-9539"
},
{
"id": "Uemura-Makoto",
"name": {
"family": "Uemura",
"given": "Makoto"
},
"orcid": "0000-0002-7375-7405"
},
{
"id": "Mizuno-Tsunefumi",
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"id": "Nakaoka-Tatsuya",
"name": {
"family": "Nakaoka",
"given": "Tatsuya"
}
},
{
"id": "Akitaya-Hiroshi",
"name": {
"family": "Akitaya",
"given": "Hiroshi"
},
"orcid": "0000-0001-6156-238X"
},
{
"id": "Gurwell-Mark-A",
"name": {
"family": "Gurwell",
"given": "Mark"
},
"orcid": "0000-0003-0685-3621"
},
{
"id": "Rao-Ramprasad",
"name": {
"family": "Rao",
"given": "Ramprasad"
},
"orcid": "0000-0002-1407-7944"
},
{
"id": "Di-Lalla-Niccol\u00f3",
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f3"
},
"orcid": "0000-0002-7574-1298"
},
{
"id": "Cibrario-Nicol\u00f3",
"name": {
"family": "Cibrario",
"given": "Nicol\u00f3"
},
"orcid": "0000-0003-3842-4493"
},
{
"id": "Donnarumma-Immacolata",
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"id": "Kim-Dawoon-E",
"name": {
"family": "Kim",
"given": "Dawoon E."
},
"orcid": "0000-0001-5717-3736"
},
{
"id": "Omodei-Nicola",
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"id": "Pacciani-Luigi",
"name": {
"family": "Pacciani",
"given": "Luigi"
},
"orcid": "0000-0001-6897-5996"
},
{
"id": "Poutanen-Juri",
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"id": "Tavecchio-Fabrizio",
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"id": "Antonelli-Lucio-A",
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Baldini-Luca",
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"id": "Baumgartner-Wayne-H",
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"id": "Bellazzini-Ronaldo",
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"id": "Bianchi-Stefano",
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"id": "Bongiorno-Stephen-D",
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"id": "Bonino-Raffaella",
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"id": "Brez-Alessandro",
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"id": "Bucciantini-Niccol\u00f3",
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f3"
},
"orcid": "0000-0002-8848-1392"
},
{
"id": "Capitanio-Fiamma",
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"id": "Castellano-Simone",
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"id": "Ciprini-Stefano",
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"id": "Costa-Enrico",
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"id": "De-Rosa-Alessandra",
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"id": "Del-Monte-Ettore",
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"id": "Di-Marco-Alessandro",
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"id": "Doroshenko-Victor",
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"id": "Dov\u010diak-Michal",
"name": {
"family": "Dovciak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"id": "Enoto-Teruaki",
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"id": "Evangelista-Yuri",
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"id": "Fabiani-Sergio",
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Ferrazzoli-Riccardo",
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Gunji-Shuichi",
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"id": "Hayashida-Kiyoshi",
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"id": "Heyl-Jeremy",
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"id": "Iwakiri-Wataru-B",
"name": {
"family": "Iwakiri",
"given": "Wataru B."
},
"orcid": "0000-0002-0207-9010"
},
{
"id": "Karas-Vladimir",
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"id": "Kitaguchi-Takao",
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"id": "Kolodziejczak--J",
"name": {
"family": "Kolodziejczak",
"given": "J."
},
"orcid": "0000-0002-0110-6136"
},
{
"id": "Krawczynski-Henric",
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"id": "La-Monaca-Fabio",
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"id": "Latronico-Luca",
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"id": "Maldera-Simone",
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"id": "Manfreda-Alberto",
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"id": "Marin-Fr\u00e9d\u00e9ric",
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"id": "Marinucci-Andrea",
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"id": "Massaro-Francesco",
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"id": "Matt-Giorgio",
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"id": "Mitsuishi-Ikuyuki",
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"id": "Ng-Stephen-Chi-Yung",
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"id": "O'Dell-Stephen-L",
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"id": "Oppedisano-Chiara",
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"id": "Papitto-Alessandro",
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"id": "Pavlov-George-G",
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"id": "Peirson-Abel-L",
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"id": "Pesce-Rollins-Melissa",
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"id": "Petrucci-Pierre-Olivier",
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"id": "Pilia-Maura",
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"id": "Possenti-Andrea",
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"id": "Ramsey-Brian-D",
"name": {
"family": "Ramsey",
"given": "Brian D."
}
},
{
"id": "Rankin-John",
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"id": "Ratheesh-Ajay",
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"id": "Romani-Roger-W",
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"id": "Sgr\u00f3-Carmelo",
"name": {
"family": "Sgr\u00f3",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"id": "Slane-Patrick",
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"id": "Soffitta-Paolo",
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0001-8916-4156"
},
{
"id": "Spandre-Gloria",
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"id": "Tamagawa-Toru",
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"id": "Taverna-Roberto",
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"id": "Tawara-Yuzuru",
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"id": "Tennant-Allyn-F",
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"id": "Thomas-Nicholas-E",
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"id": "Tombesi-Francesco",
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"id": "Trois-Alessio",
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"id": "Tsygankov-Sergey-S",
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"id": "Turolla-Roberto",
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"id": "Vink-Jacco",
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"id": "Weisskopf-Martin-C",
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"id": "Wu-Kinwah",
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"id": "Xie-Fei",
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"id": "Zane-Silvia",
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "X-Ray Polarization Observations of BL Lacertae",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nWe thank the anonymous referee for their bright comments. The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC), and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). We acknowledge financial support from ASI-INAF agreement n. 2022-14-HH.0. The research at Boston University was supported in part by National Science Foundation grant AST-2108622 and NASA Swift Guest Investigator grant 80NSSC22K0537. This research has made use of data from the RoboPol program, a collaboration between Caltech, the University of Crete, IA-FORTH, IUCAA, the MPIfR, and the Nicolaus Copernicus University, which was conducted at Skinakas Observatory in Crete, Greece. The IAA-CSIC coauthors acknowledge financial support from the Spanish \"Ministerio de Ciencia e Innovacion\" (MCINN) through the \"Center of Excellence Severo Ochoa\" award for the Instituto de Astrof\u00edsica de Andaluc\u00eda-CSIC (SEV-2017-0709). Acquisition and reduction of the POLAMI, TOP-MAPCAR, and OSN data was supported in part by MICINN through grants AYA2016-80889-P and PID2019-107847RB-C44. The POLAMI observations were carried out at the IRAM 30 m Telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain). This Letter makes use of the following ALMA director's discretionary time data under proposal ESO#2021.A.00016.T. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), MOST, and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. Some of the data reported here are based on observations obtained at the Hale Telescope, Palomar Observatory as part of a continuing collaboration between the California Institute of Technology, NASA/JPL, Yale University, and the National Astronomical Observatories of China. This research made use of Photutils, an Astropy package for detection and photometry of astronomical sources (Bradley et al. 2019). G.V.P. acknowledges support by NASA through the NASA Hubble Fellowship grant #HST-HF2-51444.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. The data in this study include observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku, and the University of Oslo, representing Denmark, Finland, and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The data presented here were obtained in part with ALFOSC, which is provided by the Instituto de Astrof\u00edsica de Andaluc\u00eda (IAA) under a joint agreement with the University of Copenhagen and NOT. E.L. was supported by Academy of Finland projects 317636 and 320045. Part of the French contribution is supported by the Scientific Research National Center (CNRS) and the French Spatial Agency (CNES). Some of the data are based on observations collected at the Observatorio de Sierra Nevada, owned and operated by the Instituto de Astrof\u00edsica de Andaluc\u00eda (IAA-CSIC). Further data are based on observations collected at the Centro Astron\u00f3mico Hispano-Alem\u00e1n (CAHA), operated jointly by Junta de Andaluc\u00eda and Consejo Superior de Investigaciones Cient\u00edficas (IAA-CSIC). D.B., S.K., R.S., and N. M. acknowledge support from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program under grant agreement No. 771282. C.C. acknowledges support by the European Research Council (ERC) under the HORIZON ERC Grants 2021 program under grant agreement No. 101040021. The Dipol-2 polarimeter was built in cooperation by the University of Turku, Finland, and the Leibniz Institut f\u00fcr Sonnenphysik, Germany, with support from the Leibniz Association grant SAW-2011-KIS-7. We are grateful to the Institute for Astronomy, University of Hawaii, for the allocated observing time. A.H. acknowledges The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This work was supported by JST, the establishment of university fellowships toward the creation of science technology innovation; grant No. JPMJFS2129. This work was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI grant Nos. JP21H01137. This work was also partially supported by Optical and Near-Infrared Astronomy Inter-University Cooperation Program from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. We are grateful to the observation and operating members of Kanata Telescope. The Submillimeter Array is a joint project between the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics and is funded by the Smithsonian Institution and the Academia Sinica. Maunakea, the location of the SMA, is a culturally important site for the indigenous Hawaiian people; we are privileged to study the cosmos from its summit. \n\nFacilities: ALMA - Atacama Large Millimeter Array, CAO:2.2m - Calar Alto Observatory's 2.2 meter Telescope, CrAO:0.7m - , Hale - Palomar Observatory's 5.1m Hale Telescope, IRAM:30m - Institute de Radioastronomie Millimetrique 30 meter telescope, IXPE - , Kanata - , LX-200 - , NOT - Nordic Optical Telescope, NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, OSN:0.9m - IAA-CSIC Observatorio de Sierra Nevada's 0.9m Telescope, OSN:1.5m - IAA-CSIC Observatorio de Sierra Nevada's 1.5m Telescope, Perkins - Lowell Observatory's 72in Perkins Telescope, Skinakas:1.3m - Skinakas Observatory 1.3 meter Telescope, SMA - SubMillimeter Array, Swift - Swift Gamma-Ray Burst Mission, TU:0.6m - , XMM-Newton. -\n\nPublished - Middei_2023_ApJL_942_L10.pdf
",
"abstract": "Blazars are a class of jet-dominated active galactic nuclei with a typical double-humped spectral energy distribution. It is of common consensus that the synchrotron emission is responsible for the low frequency peak, while the origin of the high frequency hump is still debated. The analysis of X-rays and their polarization can provide a valuable tool to understand the physical mechanisms responsible for the origin of high-energy emission of blazars. We report the first observations of BL Lacertae (BL Lac) performed with the Imaging X-ray Polarimetry Explorer, from which an upper limit to the polarization degree \u03a0_X < 12.6% was found in the 2\u20138 keV band. We contemporaneously measured the polarization in radio, infrared, and optical wavelengths. Our multiwavelength polarization analysis disfavors a significant contribution of proton-synchrotron radiation to the X-ray emission at these epochs. Instead, it supports a leptonic origin for the X-ray emission in BL Lac.",
"date": "2023-01-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "942",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L10",
"id_number": "CaltechAUTHORS:20230314-846094500.79",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230314-846094500.79",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "NSF",
"grant_number": "AST-2108622"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0537"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2016-80889-P"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "PID2019-107847RB-C44"
},
{
"agency": "Institut national des sciences de l'Univers (INSU)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Max Planck Society"
},
{
"agency": "Instituto Geogr\u00e1fico Nacional (IGN)"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51444.001-A"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "Academy of Finland",
"grant_number": "317636"
},
{
"agency": "Academy of Finland",
"grant_number": "320045"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "771282"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101040021"
},
{
"agency": "Leibniz Association",
"grant_number": "SAW-2011-KIS-7"
},
{
"agency": "Japan Science and Technology Agency",
"grant_number": "JPMJFS2129"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP21H01137"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)"
},
{
"agency": "Smithsonian Institution"
},
{
"agency": "Academia Sinica"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Infrared-Processing-and-Analysis-Center-(IPAC)"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/aca281",
"primary_object": {
"basename": "Middei_2023_ApJL_942_L10.pdf",
"url": "https://authors.library.caltech.edu/records/sm7k9-1qe15/files/Middei_2023_ApJL_942_L10.pdf"
},
"pub_year": "2023",
"author_list": "Middei, Riccardo; Liodakis, Ioannis; et al."
},
{
"id": "https://authors.library.caltech.edu/records/rnp3v-80k61",
"eprint_id": 119997,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:37:48",
"lastmod": "2023-10-25 16:48:47",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Diaz-Yaherlyn",
"name": {
"family": "Diaz",
"given": "Y."
},
"orcid": "0000-0002-8604-1158"
},
{
"id": "Hern\u00e1ndez-Garc\u00eda-Lorena",
"name": {
"family": "Hern\u00e1ndez-Garc\u00eda",
"given": "L."
},
"orcid": "0000-0002-8606-6961"
},
{
"id": "Ar\u00e9valo-Patricia",
"name": {
"family": "Ar\u00e9valo",
"given": "P."
},
"orcid": "0000-0001-8503-9809"
},
{
"id": "L\u00f3pez-Navas-E",
"name": {
"family": "L\u00f3pez-Navas",
"given": "E."
}
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Gonz\u00e1lez-Mart\u00edn-Omaira",
"name": {
"family": "Gonz\u00e1lez-Mart\u00edn",
"given": "O."
},
"orcid": "0000-0002-2356-8358"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Osorio-Clavijo-Natalia",
"name": {
"family": "Osorio-Clavijo",
"given": "N."
},
"orcid": "0000-0002-3467-8077"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Malizia-Angela",
"name": {
"family": "Malizia",
"given": "A."
},
"orcid": "0000-0002-6558-1163"
}
]
},
"title": "Constraining the X-ray reflection in low accretion-rate active galactic nuclei using XMM-Newton, NuSTAR, and Swift",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe-to-Open model. Subscribe to A&A to support open access publication. \n\nWe thank the referee for the valuable comments that improved the manuscript. D.Y. acknowledges financial support from the Doctorate Fellowship program FIB-UV of the Universidad de Valpara\u00edso and the Max Planck Society by a Max Planck partner group. LHG acknowledges funds by ANID \u2013 Millennium Science Initiative Program \u2013 ICN12_009 awarded to the Millennium Institute of Astrophysics (MAS). ELN acknowledges financial support from ANID Beca 21200718. CR acknowledges support from the Fondecyt Iniciacion grant 11190831 and ANID BASAL project FB210003. MB acknowledges support from the YCAA Prize Postdoctoral Fellowship. NOC acknowledges support from CONACyT. J.A.G. acknowledges support from NASA grant 80NSSC21K1567.\n\nPublished - aa44678-22.pdf
",
"abstract": "An interesting feature of active galactic nuclei (AGN) accreting at low rates is the weakness of the reflection features in their X-ray spectra, which may result from the gradual disappearance of the torus with decreasing accretion rates. It has been suggested that low-luminosity AGN (LLAGN) would exhibit a different reflector configuration than high-luminosity AGN, covering a smaller fraction of the sky or simply having less material. Additionally, we note that the determination of the spectral index (\u0393) and the cut-off energy of the primary power-law emission is affected by the inclusion of reflection models, showing their importance in studying accretion mechanisms. This is especially valid in the case of the LLAGN which has previously shown a high dispersion in the relation between \u0393 and the accretion rate. \n\nAims. Our purpose is to constrain the geometry and column density of the reflector in a sample of LLAGN covering a broad X-ray range of energy by combining data from XMM-Newton+ NuSTAR + Swift. The spectral analysis also allows us to investigate the accretion mechanism in LLAGN. \n\nMethods. We used XMM-Newton+ NuSTAR + Swift observations of a hard X-ray flux-limited sample of 17 LLAGN from BASS/DR2 with accretion rates of \u03bb_(Edd)\u2004=\u2004L_(Bol)/L_(Edd)\u2004< 10\u207b\u00b3. We fit all spectra using the reflection model for torus (BORUS) and accretion disk (XILLVER) reflectors. \n\nResults. We found a tentative correlation between the torus column density and the accretion rate, with LLAGN showing a lower column density than the high-luminosity objects. We also confirm the relation between \u0393 and \u03bb_(Edd), with a smaller scatter than previously reported, thanks to the inclusion of high-energy data and the reflection models. Our results are consistent with a break at \u03bb_(Edd)\u2004\u223c\u200410\u207b\u00b3, which is suggestive of a different accretion mechanism compared with higher accretion AGN.",
"date": "2023-01",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "669",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A114",
"id_number": "CaltechAUTHORS:20230314-844891400.8",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230314-844891400.8",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Universidad de Valpara\u00edso"
},
{
"agency": "Max Planck Society"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "21200718"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1567"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1051/0004-6361/202244678",
"primary_object": {
"basename": "aa44678-22.pdf",
"url": "https://authors.library.caltech.edu/records/rnp3v-80k61/files/aa44678-22.pdf"
},
"pub_year": "2023",
"author_list": "Diaz, Y.; Hern\u00e1ndez-Garc\u00eda, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kxph2-e6861",
"eprint_id": 119173,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:36:14",
"lastmod": "2023-10-24 23:50:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bucik-Radoslav",
"name": {
"family": "Bucik",
"given": "R."
},
"orcid": "0000-0001-7381-6949"
},
{
"id": "Mason-Glenn-M",
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "G\u00f3mez-Herrero-Ra\u00fal",
"name": {
"family": "G\u00f3mez-Herrero",
"given": "R."
},
"orcid": "0000-0002-5705-9236"
},
{
"id": "Krupar-Vratislav",
"name": {
"family": "Krupar",
"given": "V."
},
"orcid": "0000-0001-6185-3945"
},
{
"id": "Lario-David",
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"id": "Starkey-Michael-J",
"name": {
"family": "Starkey",
"given": "M. J."
},
"orcid": "0000-0001-7514-6571"
},
{
"id": "Ho-George-C",
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Rodr\u00edguez-Pacheco-Javier",
"name": {
"family": "Rodr\u00edguez-Pacheco",
"given": "J."
},
"orcid": "0000-0002-4240-1115"
},
{
"id": "Wimmer-Schweingruber-Robert-F",
"name": {
"family": "Wimmer-Schweingruber",
"given": "R. F."
},
"orcid": "0000-0002-7388-173X"
},
{
"id": "Espinosa-Lara-Francisco",
"name": {
"family": "Espinosa Lara",
"given": "F."
},
"orcid": "0000-0001-9039-8822"
},
{
"id": "Tadesse-T",
"name": {
"family": "Tadesse",
"given": "T."
}
},
{
"id": "Balmaceda-Laura-A",
"name": {
"family": "Balmaceda",
"given": "L."
},
"orcid": "0000-0003-1162-5498"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Dayeh-Maher-A",
"name": {
"family": "Dayeh",
"given": "M. A."
},
"orcid": "0000-0001-9323-1200"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "K\u00fchl-Patrick",
"name": {
"family": "K\u00fchl",
"given": "P."
},
"orcid": "0000-0002-3758-9272"
},
{
"id": "Nitta-Nariaki-V",
"name": {
"family": "Nitta",
"given": "N. V."
},
"orcid": "0000-0001-6119-0221"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Z. G."
},
"orcid": "0000-0002-9246-996X"
}
]
},
"title": "The first gradual solar energetic particle event with an enhanced \u00b3He abundance on Solar Orbiter",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Authors 2022. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nR. Bu\u010d\u00edk was supported by NASA grants 80NSSC21K1316, 80NSSC22K0757 and NASA contract NNN06AA01C. V. Krupar acknowledges the support by NASA under grants 18-2HSWO2182-0010 and 19-HSR-192-0143. Solar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. The Suprathermal Ion Spectrograph (SIS) is a European facility instrument funded by ESA. The SIS instrument was constructed by the Johns Hopkins Applied Physics Lab. and CAU Kiel. Post launch operation of SIS at APL is funded by NASA contract NNN06AA01C. The UAH team acknowledges the financial support of the Spanish MINCIN Project PID2019-104863RBI00/AEI/10.13039/501100011033. We thank the German Space Agency, DLR, for the build and support of STEP, EPT, and HET with grants 50OT0901, 50OT1202, 50OT1702, and 50OT2002. Solar Orbiter magnetometer data was provided by Imperial College London and supported by the UK Space Agency. The LASCO C2 CME catalog is generated and maintained at the CDAW Data Center by NASA and The Catholic University of America in cooperation with the Naval Research Laboratory. SOHO is a project of international cooperation between ESA and NASA.\n\nPublished - aa45037-22.pdf
",
"abstract": "The origin of \u00b3He bundance enhancements in gradual solar energetic particle (SEP) events remains largely unexplained. Two mechanisms have been suggested: the reacceleration of remnant flare material by coronal mass ejection (CME)-driven shocks in interplanetary space, and concomitant activity in the corona. We explore the first gradual SEP event with enhanced 3He abundance that was observed by Solar Orbiter. The event started on 2020 November 24 and was associated with a relatively fast halo CME. During the event, the spacecraft was at 0.9 au from the Sun. The event-averaged \u00b3He/\u2074He abundance ratio is 24 times higher than the coronal or solar wind value, and the timing of the \u00b3He intensity was similar to that of other species. We inspected available imaging, radio observations, and the spacecraft magnetic connection to the CME source. The most probable cause of the enhanced \u00b3He ions remaining from a preceding long period of 3He-rich SEPs on 2020 November 17\u201323.",
"date": "2023-01",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "669",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A13",
"id_number": "CaltechAUTHORS:20230209-988069100.7",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230209-988069100.7",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC21K1316"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0757"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "18-2HSWO2182- 0010"
},
{
"agency": "NASA",
"grant_number": "19-HSR-192-0143"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MINCIN)",
"grant_number": "PID2019-104863RBI00/AEI/10.13039/501100011033"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT0901"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT1202"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT1702"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT2002"
},
{
"agency": "United Kingdom Space Agency (UKSA)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202245037",
"primary_object": {
"basename": "aa45037-22.pdf",
"url": "https://authors.library.caltech.edu/records/kxph2-e6861/files/aa45037-22.pdf"
},
"pub_year": "2023",
"author_list": "Bucik, R.; Mason, G. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5x05z-f7d06",
"eprint_id": 121348,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:39:36",
"lastmod": "2023-10-23 20:16:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Violette-Daniel-P",
"name": {
"family": "Violette",
"given": "Daniel P."
},
"orcid": "0000-0002-5943-4730"
},
{
"id": "Allen-Branden",
"name": {
"family": "Allen",
"given": "Branden"
}
},
{
"id": "Hong-Jaesub",
"name": {
"family": "Hong",
"given": "Jaesub"
},
"orcid": "0000-0002-6089-5390"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Grindlay-Jonathan-E",
"name": {
"family": "Grindlay",
"given": "Jonathan"
},
"orcid": "0000-0002-1323-5314"
}
]
},
"title": "Tuning of nuclear spectroscopic telescope array application specific integrated circuits to improve low energy threshold of future hard x-ray imaging detectors",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Mechanical Engineering; Astronomy and Astrophysics; Instrumentation; Control and Systems Engineering; Electronic, Optical and Magnetic Materials",
"note": "\u00a9 2023 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nWe would like to thank Fiona A. Harrison, Jill A. Burnham, and W. Rick Cook of the California Institute of Technology along with the rest of the NuSTAR Team for developing the NuASIC and providing valuable information to facilitate its operation and testing. DPV is grateful to MA and KV for useful advice. This work was supported by NASA APRA (Grant No. NNX17AE62G). DPV is supported by the NASA FINESST Fellowship (Grant No. 80NSSC20K1537).\n\nPublished - 016001_1.pdf
",
"abstract": "Detector commanding, processing and readout of spaceborne instrumentation is often accomplished with application specific integrated circuits (ASICs). The ASIC designed for the nuclear spectroscopic telescope array (NuSTAR) mission enables future tiled CdZnTe (CZT) detector array readout for x-ray detectors, such as the high resolution energetic x-ray imager (HREXI). Modified NuSTAR ASIC (NuASIC) gain settings have been implemented for HREXI's broader targeted imaging energy range (3 to 300 keV) compared with NuSTAR (2 to 79 keV), which may require updated NuASIC internal parameters for optimal energy resolution. To reach HREXI's targeted low energy threshold, we have also enabled the NuASIC's \"charge pump mode,\" which introduces an additional tuning parameter. We describe the mechanics of the NuASIC's adjustable parameters and use our recently developed ASIC test stand to probe a \"bare\" NuASIC using its internal test pulser. We record the effects of parameter tuning on the device's electronics noise and low energy threshold and report the optimal set of parameters for HREXI's updated gain setting. We detail a semiautomated procedure to derive the optimal parameters for each of HREXI's large area closely tiled NuASIC/CZT detectors to expedite instrument integration.",
"date": "2023-01",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "9",
"number": "1",
"publisher": "Society of Photo-optical Instrumentation Engineers",
"pagerange": "Art. No. 016001",
"id_number": "CaltechAUTHORS:20230509-880670200.5",
"issn": "2329-4124",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230509-880670200.5",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX17AE62G"
},
{
"agency": "NASA Earth and Space Science and Technology Fellowship",
"grant_number": "80NSSC20K1537"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1117/1.jatis.9.1.016001",
"primary_object": {
"basename": "016001_1.pdf",
"url": "https://authors.library.caltech.edu/records/5x05z-f7d06/files/016001_1.pdf"
},
"pub_year": "2023",
"author_list": "Violette, Daniel P.; Allen, Branden; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dqsvz-9ty06",
"eprint_id": 120045,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:31:54",
"lastmod": "2025-11-20 20:44:33",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xie-Fei",
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Liu",
"given": "Kuan"
}
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Watanabe",
"given": "Eri"
},
"orcid": "0000-0003-0622-8703"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
}
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Sgr\u00f3",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicolas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Vela pulsar wind nebula X-rays are polarized to near the synchrotron limit",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Multidisciplinary",
"note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2022. \n\nThe IXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and is led and managed by the Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF and INFN) that are distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). The research at Guangxi University was supported in part by National Natural Science Foundation of China (grant no. 12133003). The research at Boston University was supported in part by National Science Foundation grant AST-2108622. I.A. acknowledges financial support from the Spanish 'Ministerio de Ciencia e Innovaci\u00f3n' (MCINN) through the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrof\u00edsica de Andaluc\u00eda-CSIC (SEV-2017-0709) and through grants AYA2016-80889-P and PID2019-107847RB-C44. \n\nContributions. F.X. led the data analysis and the writing of the paper. A.D.M. and F.L.M. performed the spectropolarimetric analysis and contributed to the paper. F. Muleri and J.R. contributed to the data analysis and energy calibration of the dataset. K.L. and N.B. contributed to the data analysis and result interpretation. R.W.R. and L.L. helped to revise the manuscript. E. Costa, P. Soffitta, M.B., S.F., R.F., M. Pilia and A.T. contributed to the interpretation of the results and to text revisions. N.D.L., S.G., N.O., M.N. and E.W. performed independent analysis of the data. The other authors contributed to the design of the mission, to the calibration of the instrument, to the definition of its scientific case and to the planning of the observations. All of the authors provided inputs and comments on the manuscript. \n\nData availability. IXPE data are available through the NASA's HEASARC data archive (https://heasarc.gsfc.nasa.gov). Other derived data supporting the findings of this study are available from the corresponding author on request. Source data are provided with this paper. \n\nCode availability. The High Energy Astrophysics Science Archive Research Center (HEASARC) developed the HEASOFT (HEASARC Software). We used the HEASOFT v.6.30.1 package for the spectropolarimetric IXPE data analysis, which is available online (https://heasarc.gsfc.nasa.gov/docs/software/heasoft/). The proper instrument response functions are provided by the IXPE Team as a part of the IXPE calibration database released on 14 March 2022 are and available in the HEASARC Calibration Database (https://heasarc.gsfc.nasa.gov/docs/heasarc/caldb/caldb_supported_missions.html). The software developed by IXPE collaboration is available publicly online (https://ixpeobssim.readthedocs.io/en/latest/?badge=latest). Information supporting the findings of this study is available from the corresponding author on request. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41586_2022_5476_Fig3_ESM.jpg
Supplemental Material - 41586_2022_5476_Fig4_ESM.jpg
Supplemental Material - 41586_2022_5476_Fig5_ESM.jpg
Supplemental Material - 41586_2022_5476_Fig6_ESM.jpg
Supplemental Material - 41586_2022_5476_Fig7_ESM.jpg
Supplemental Material - 41586_2022_5476_Fig8_ESM.jpg
Supplemental Material - 41586_2022_5476_MOESM1_ESM.xlsx
Supplemental Material - 41586_2022_5476_MOESM2_ESM.xlsx
Supplemental Material - 41586_2022_5476_Tab1_ESM.jpg
Supplemental Material - 41586_2022_5476_Tab2_ESM.jpg
Supplemental Material - 41586_2022_5476_Tab3_ESM.jpg
Supplemental Material - 41586_2022_5476_Tab4_ESM.jpg
",
"abstract": "Pulsar wind nebulae are formed when outflows of relativistic electrons and positrons hit the surrounding supernova remnant or interstellar medium at a shock front. The Vela pulsar wind nebula is powered by a young pulsar (B0833-45, aged 11,000\u2009years) and located inside an extended structure called Vela X, which is itself inside the supernova remnant. Previous X-ray observations revealed two prominent arcs that are bisected by a jet and counter jet. Radio maps have shown high linear polarization of 60% in the outer regions of the nebula. Here we report an X-ray observation of the inner part of the nebula, where polarization can exceed 60% at the leading edge\u2014approaching the theoretical limit of what can be produced by synchrotron emission. We infer that, in contrast with the case of the supernova remnant, the electrons in the pulsar wind nebula are accelerated with little or no turbulence in a highly uniform magnetic field.",
"date": "2022-12-22",
"date_type": "published",
"publication": "Nature",
"volume": "612",
"number": "7941",
"publisher": "Nature Publishing Group",
"pagerange": "658-660",
"id_number": "CaltechAUTHORS:20230314-846094500.78",
"issn": "0028-0836",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230314-846094500.78",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12133003"
},
{
"agency": "NSF",
"grant_number": "AST-2108622"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "AYA2016-80889-P"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PID2019-107847RB-C44"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41586-022-05476-5",
"primary_object": {
"basename": "41586_2022_5476_Fig7_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Fig7_ESM.jpg"
},
"related_objects": [
{
"basename": "41586_2022_5476_MOESM2_ESM.xlsx",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_MOESM2_ESM.xlsx"
},
{
"basename": "41586_2022_5476_Tab1_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Tab1_ESM.jpg"
},
{
"basename": "41586_2022_5476_Tab3_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Tab3_ESM.jpg"
},
{
"basename": "41586_2022_5476_Tab4_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Tab4_ESM.jpg"
},
{
"basename": "41586_2022_5476_Fig3_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Fig3_ESM.jpg"
},
{
"basename": "41586_2022_5476_Fig6_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Fig6_ESM.jpg"
},
{
"basename": "41586_2022_5476_Fig8_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Fig8_ESM.jpg"
},
{
"basename": "41586_2022_5476_MOESM1_ESM.xlsx",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_MOESM1_ESM.xlsx"
},
{
"basename": "41586_2022_5476_Tab2_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Tab2_ESM.jpg"
},
{
"basename": "41586_2022_5476_Fig4_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Fig4_ESM.jpg"
},
{
"basename": "41586_2022_5476_Fig5_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/dqsvz-9ty06/files/41586_2022_5476_Fig5_ESM.jpg"
}
],
"pub_year": "2022",
"author_list": "Xie, Fei; Di Marco, Alessandro; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mb3ja-v5e51",
"eprint_id": 119018,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:27:27",
"lastmod": "2025-11-21 01:09:20",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "G."
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Thalhammer-Philipp",
"name": {
"family": "Thalhammer",
"given": "P."
},
"orcid": "0000-0001-6269-2821"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "M. C."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "R. M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Grinberg-Victoria",
"name": {
"family": "Grinberg",
"given": "V."
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "H."
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "J. A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "NuSTAR Spectral Analysis beyond 79 keV with Stray Light",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "G.M. would like to thank Lorenzo Natalucci for the helpful comments. J.A.G. acknowledges support from NASA grant 80NSSC19K1020 and from the Alexander von Humboldt Foundation. The material is based upon work supported by NASA under award No. 80GSFC21M0002. This work was supported by NASA under grant No. 80NSSC19K1023 issued through the NNH18ZDA001N Astrophysics Data Analysis Program (ADAP). This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).",
"abstract": "Due to the structure of the NuSTAR telescope, photons at a large off axis (>1\u00b0) can reach the detectors directly (stray light), without passing through the instrument optics. At these off-axis angles NuSTAR essentially turns into a collimated instrument and the spectrum can extend to energies above the Pt K edge (79 keV) of the multilayers, which limits the effective area bandpass of the optics. We present the first scientific spectral analysis beyond 79 keV using a Cygnus X-1 observation in StrayCats: the catalog of stray light observations. This serendipitous stray light observation occurred simultaneously with an INTEGRAL observation. When the spectra are modeled together in the 30\u2013120 keV energy band, we find that the NuSTAR stray light flux is well calibrated and constrained to be consistent with the INTEGRAL flux at the 90% confidence level. Furthermore, we explain how to treat the background of the stray light spectral analysis, which is especially important at high energies.",
"date": "2022-12-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "941",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 35",
"id_number": "CaltechAUTHORS:20230203-893210800.24",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230203-893210800.24",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K1020"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "80GSFC21M0002"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1023"
},
{
"agency": "NASA",
"grant_number": "NNH18ZDA001N"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac8c94",
"pub_year": "2022",
"author_list": "Mastroserio, G.; Grefenstette, B. W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9c2v7-4xh90",
"eprint_id": 119615,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:27:45",
"lastmod": "2025-11-20 20:30:19",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Tsygankov-Sergey-S",
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Mushtukov",
"given": "Alexander A."
},
"orcid": "0000-0003-2306-419X"
},
{
"id": "Caiazzo-Ilaria",
"name": {
"family": "Caiazzo",
"given": "Ilaria"
},
"orcid": "0000-0002-4770-5388"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Forsblom",
"given": "Sofia V."
},
"orcid": "0000-0001-9167-2790"
},
{
"name": {
"family": "Gonz\u00e1lez-Caniulef",
"given": "Denis"
},
"orcid": "0000-0001-5848-0180"
},
{
"name": {
"family": "Klawin",
"given": "Moritz"
},
"orcid": "0000-0001-9162-6639"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Malacaria",
"given": "Christian"
},
"orcid": "0000-0002-0380-0041"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Ng",
"given": "Mason"
},
"orcid": "0000-0002-0940-6563"
},
{
"name": {
"family": "Suleimanov",
"given": "Valery F."
},
"orcid": "0000-0003-3733-7267"
},
{
"name": {
"family": "Sunyaev",
"given": "Rashid A."
},
"orcid": "0000-0002-2764-7192"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Gesu",
"given": "Laura Di"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Lalla",
"given": "Niccol\u00f2 Di"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "Chi-Yung"
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "The X-Ray Polarimetry View of the Accreting Pulsar Cen X-3",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThe Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC) with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC). \n\nWe acknowledge support from Russian Science Foundation grant 20-12-00364 (S.S.T., J.P., V.F.S.); Academy of Finland grants 333112, 349144, 349373, and 349906 (S.S.T., J.P.); German Academic Exchange Service (DAAD) travel grant 57525212 (V.D., V.F.S.); German Research Foundation (DFG) grant WE 1312/53-1 (V.F.S.); the UKRI Stephen Hawking fellowship; and the Netherlands Organization for Scientific Research Veni fellowship (A.A.M.). \n\nFacility: IXPE. - \n\nSoftware: astropy (Astropy Collaboration et al. 2013, 2018), xspec (Arnaud 1996), ixpeobssim (Baldini et al. 2022), emcee (Foreman-Mackey et al. 2013).\n\nPublished - Tsygankov_2022_ApJL_941_L14.pdf
",
"abstract": "The first X-ray pulsar, Cen X-3, was discovered 50 yr ago. Radiation from such objects is expected to be highly polarized due to birefringence of plasma and vacuum associated with propagation of photons in the presence of the strong magnetic field. Here we present results of the observations of Cen X-3 performed with the Imaging X-ray Polarimetry Explorer. The source exhibited significant flux variability and was observed in two states different by a factor of \u223c20 in flux. In the low-luminosity state, no significant polarization was found in either pulse phase-averaged (with a 3\u03c3 upper limit of 12%) or phase-resolved (the 3\u03c3 upper limits are 20%\u201330%) data. In the bright state, the polarization degree of 5.8% \u00b1 0.3% and polarization angle of 49.\u00b06 \u00b1 1.\u00b05 with a significance of about 20\u03c3 were measured from the spectropolarimetric analysis of the phase-averaged data. The phase-resolved analysis showed a significant anticorrelation between the flux and the polarization degree, as well as strong variations of the polarization angle. The fit with the rotating vector model indicates a position angle of the pulsar spin axis of about 49\u00b0 and a magnetic obliquity of 17\u00b0. The detected relatively low polarization can be explained if the upper layers of the neutron star surface are overheated by the accreted matter and the conversion of the polarization modes occurs within the transition region between the upper hot layer and a cooler underlying atmosphere. A fraction of polarization signal can also be produced by reflection of radiation from the neutron star surface and the accretion curtain.",
"date": "2022-12-10",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "941",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L14",
"id_number": "CaltechAUTHORS:20230301-701033500.20",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230301-701033500.20",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Russian Science Foundation",
"grant_number": "20-12-00364"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
},
{
"agency": "Academy of Finland",
"grant_number": "349144"
},
{
"agency": "Academy of Finland",
"grant_number": "349373"
},
{
"agency": "Academy of Finland",
"grant_number": "349906"
},
{
"agency": "Deutscher Akademischer Austauschdienst (DAAD)",
"grant_number": "57525212"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "WE 1312/53-1"
},
{
"agency": "UK Research and Innovation"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/aca486",
"primary_object": {
"basename": "Tsygankov_2022_ApJL_941_L14.pdf",
"url": "https://authors.library.caltech.edu/records/9c2v7-4xh90/files/Tsygankov_2022_ApJL_941_L14.pdf"
},
"pub_year": "2022",
"author_list": "Tsygankov, Sergey S.; Doroshenko, Victor; et al."
},
{
"id": "https://authors.library.caltech.edu/records/47qwz-pzq56",
"eprint_id": 118892,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:20:09",
"lastmod": "2025-11-20 20:59:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Chalise-Sulov",
"name": {
"family": "Chalise",
"given": "S."
},
"orcid": "0000-0002-5641-0442"
},
{
"id": "Lohfink-Anne-M",
"name": {
"family": "Lohfink",
"given": "A. M."
}
},
{
"id": "Chauhan-Jaiverdhan",
"name": {
"family": "Chauhan",
"given": "J."
},
"orcid": "0000-0003-0330-1901"
},
{
"id": "Russell-Thomas-D",
"name": {
"family": "Russell",
"given": "T. D."
},
"orcid": "0000-0001-6958-8891"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"id": "Mallick-Labani",
"name": {
"family": "Mallick",
"given": "L."
},
"orcid": "0000-0001-8624-9162"
}
]
},
"title": "Broad-band spectral analysis of Mrk\u2009926 using multi-epoch X-ray observations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has also made use of the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. We would like to thank Javier Garc\u00eda and Andy Fabian for helpful discussions.",
"abstract": "The X-ray spectra of some active galactic nuclei (AGNs) show a soft X-ray excess, emission in excess to the extrapolated primary X-ray continuum below 2\u2009keV. Recent studies have shown that this soft excess can be described well as originating from either a relativistic ionized reflection, the extreme blurring of the reprocessed emission from the innermost region of the accretion disc, or Comptonization from an optically thick and warm region called the 'warm corona', in which electron scattering is the dominant source of opacity. To constrain the origin of the soft excess in the Seyfert 1 galaxy Mrk\u2009926, we carry out a multi-epoch X-ray spectral study using observations from Suzaku (2009), XMM\u2013Newton and NuSTAR (2016), and NuSTAR and Swift-XRT (2021). The broad-band X-ray spectra of Mrk\u2009926 contains a thermally Comptonized primary continuum, a variable soft excess, and distant reflection. We find that in Mrk\u2009926 as in so many sources, it is difficult to make a definite statement as to what is causing the observed soft excess. A warm coronal-like component is slightly preferred by the data but a reflection origin is also possible. Using archival radio data, we detect an optically thin radio component in our broad-band study of Mrk\u2009926. While this component is consistent with an optically thin radio jet, future multiwavelength observations including high spatial resolution radio observations at multiple frequencies are required to probe the origin of the radio emission in more detail.",
"date": "2022-12",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "517",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "4788-4794",
"id_number": "CaltechAUTHORS:20230123-451320900.19",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230123-451320900.19",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/stac2953",
"pub_year": "2022",
"author_list": "Chalise, S.; Lohfink, A. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/1aqnx-1j226",
"eprint_id": 117757,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:18:28",
"lastmod": "2025-11-21 00:33:31",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Doroshenko-Victor",
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Suleimanov",
"given": "Valery F."
},
"orcid": "0000-0003-3733-7267"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Caiazzo-Ilaria",
"name": {
"family": "Caiazzo",
"given": "Ilaria"
},
"orcid": "0000-0002-4770-5388"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Mushtukov",
"given": "Alexander A."
}
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
}
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Santangelo",
"given": "Andrea"
},
"orcid": "0000-0003-4187-9560"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Staubert",
"given": "R\u00fcdiger"
},
"orcid": "0000-0003-1498-1543"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
}
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
}
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
}
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
}
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
}
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
}
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
}
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "Chi-Yung"
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
}
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Sunyaev",
"given": "Rashid A."
}
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
}
},
{
"name": {
"family": "Thomas",
"given": "Nicolas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
}
},
{
"name": {
"family": "Xie",
"given": "Fei"
}
}
]
},
"title": "Determination of X-ray pulsar geometry with IXPE polarimetry",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astronomy and Astrophysics",
"note": "This Article is based on observations made by IXPE, a joint US and Italian mission. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at the NASA Goddard Space Flight Center (GSFC). The US contribution is supported by NASA and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract number NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract number ASI-OHBI-2017-12-I.0, agreement numbers ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. V.D. and V.F.S. acknowledge support from the German Academic Exchange Service (DAAD) under travel grant number 57525212. J.P. and S.S.T. thank the Russian Science Foundation for support under grant number 20-12-00364 and the Academy of Finland for support under grant numbers 333112, 349144, 349373 and 349906. V.F.S. thanks the German Research Foundation (DFG) for grant number WE 1312/53-1. I.C. is a Sherman Fairchild Fellow at Caltech and thanks the Burke Institute at Caltech for supporting her research. A.A.M. acknowledges support from the Netherlands Organization for Scientific Research Veni Fellowship.",
"abstract": "Using observations of X-ray pulsar Hercules X-1 by the Imaging X-ray Polarimetry Explorer we report a highly significant (>17\u03c3) detection of the polarization signal from an accreting neutron star. The observed degree of linear polarization of ~10% is far below theoretical expectations for this object, and stays low throughout the spin cycle of the pulsar. Both the degree and angle of polarization exhibit variability with the pulse phase, allowing us to measure the pulsar spin position angle 57(2)\u2009deg and the magnetic obliquity 12(4)\u2009deg, which is an essential step towards detailed modelling of the intrinsic emission of X-ray pulsars. Combining our results with the optical polarimetric data, we find that the spin axis of the neutron star and the angular momentum of the binary orbit are misaligned by at least ~20\u2009deg, which is a strong argument in support of the models explaining the stability of the observed superorbital variability with the precession of the neutron star.",
"date": "2022-12",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "6",
"number": "12",
"publisher": "Nature Publishing Group",
"pagerange": "1433-1443",
"id_number": "CaltechAUTHORS:20221107-999291600.31",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221107-999291600.31",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Deutscher Akademischer Austauschdienst (DAAD)",
"grant_number": "57525212"
},
{
"agency": "Russian Science Foundation",
"grant_number": "20-12-00364"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Academy of Finland",
"grant_number": "349144"
},
{
"agency": "Academy of Finland",
"grant_number": "349373"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Academy of Finland",
"grant_number": "349906"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "WE 1312/53-1"
},
{
"agency": "Sherman Fairchild Foundation"
},
{
"agency": "Walter Burke Institute for Theoretical Physics, Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "TAPIR"
},
{
"id": "Walter-Burke-Institute-for-Theoretical-Physics"
}
]
},
"doi": "10.1038/s41550-022-01799-5",
"pub_year": "2022",
"author_list": "Doroshenko, Victor; Poutanen, Juri; et al."
},
{
"id": "https://authors.library.caltech.edu/records/t6yqd-scd51",
"eprint_id": 118901,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:16:50",
"lastmod": "2025-11-20 20:41:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Temple-Matthew-J",
"name": {
"family": "Temple",
"given": "Matthew J."
},
"orcid": "0000-0001-8433-550X"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Rojas-Alejandra-F",
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Padilla-Gonzalez-Estefania",
"name": {
"family": "Padilla\u00a0Gonzalez",
"given": "Estefania"
},
"orcid": "0000-0003-0209-9246"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Riffel-Rog\u00e9rio",
"name": {
"family": "Riffel",
"given": "Rog\u00e9rio"
},
"orcid": "0000-0002-1321-1320"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "BASS XXXIX: Swift-BAT AGN with changing-look optical spectra",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "We thank the anonymous referee for a constructive report. MJT acknowledges support from CONICYT (Fondo ALMA 31190036) and a FONDECYT fellowship (Proyecto 3220516). CR acknowledges support from FONDECYT (Iniciacion grant 11190831) and ANID BASAL project FB210003. MJK acknowledges support from NASA (ADAP award NNH16CT03C). BT acknowledges support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement 950533) and from the Israel Science Foundation (grant 1849/19). FEB acknowledges support from the ANID Millennium Science Initiative Program (ICN12_009), CATA-BASAL (ACE21000 and FB210003) and FONDECYT Regular (1190818 and 1200495). AFR acknowledges support from FONDECYT Postdoctorado Proyecto 3210157. KO acknowledges support from the Korea Astronomy and Space Science Institute under the R&D program (Project No. 2022-1-868-04) supervised by the Ministry of Science and ICT and from the National Research Foundation of Korea (NRF-2020R1C1C1005462). FR acknowledges support from PRIN MIUR 2017PH3WAT ('Black hole winds and the baryon life cycle of galaxies'). RR thanks Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq, Proj. 311223/2020-6, 304927/2017-1 and 400352/2016-8), Funda\u00e7\u00e3o de amparo \u00e0 pesquisa do Rio Grande do Sul (FAPERGS, Proj. 16/2551-0000251-7 and 19/1750-2), Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES, Proj. 0001).\n\nThis research has made use of the NASA/IPAC Extragalactic Data base (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology.",
"abstract": "Changing-look (CL) AGN are unique probes of accretion onto supermassive black holes (SMBHs), especially when simultaneous observations in complementary wavebands allow investigations into the properties of their accretion flows. We present the results of a search for CL behaviour in 412 Swift-BAT detected AGN with multiple epochs of optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS). 125 of these AGN also have 14\u2013195\u2009\u2009keV ultra-hard X-ray light curves from Swift-BAT which are contemporaneous with the epochs of optical spectroscopy. Eight CL events are presented for the first time, where the appearance or disappearance of broad Balmer line emission leads to a change in the observed Seyfert type classification. Combining with known events from the literature, 21 AGN from BASS are now known to display CL behaviour. Nine CL events have 14\u2013195\u2009\u2009keV data available, and five of these CL events can be associated with significant changes in their 14\u2013195\u2009\u2009keV flux from BAT. The ultra-hard X-ray flux is less affected by obscuration and so these changes in the 14\u2013195\u2009keV band suggest that the majority of our CL events are not due to changes in line-of-sight obscuration. We derive a CL rate of 0.7\u20136.2 per\u2009cent on 10\u201325 yr time-scales, and show that many transitions happen within at most a few years. Our results motivate further multiwavelength observations with higher cadence to better understand the variability physics of accretion onto SMBHs.",
"date": "2022-11-29",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "518",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2938-2953",
"id_number": "CaltechAUTHORS:20230123-451841300.37",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230123-451841300.37",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ALMA 31190036"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3220516"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE21000"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "Korea Astronomy and Space Science Institute (KASI)",
"grant_number": "2022-1-868-04"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca (MIUR)",
"grant_number": "2017PH3WAT"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "311223/2020-6"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "304927/2017-1"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "400352/2016-8"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "16/2551-0000251-7"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "19/1750-2"
},
{
"agency": "Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)",
"grant_number": "0001"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac3279",
"pub_year": "2022",
"author_list": "Temple, Matthew J.; Ricci, Claudio; et al."
},
{
"id": "https://authors.library.caltech.edu/records/99bvb-e7812",
"eprint_id": 118318,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:14:08",
"lastmod": "2025-11-20 23:03:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Liodakis-Ioannis",
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Berdyugin",
"given": "Andrei V."
},
"orcid": "0000-0002-9353-5164"
},
{
"name": {
"family": "Bernardos",
"given": "Maria I."
},
"orcid": "0000-0001-8872-1168"
},
{
"name": {
"family": "Bonnoli",
"given": "Giacomo"
},
"orcid": "0000-0003-2464-9077"
},
{
"name": {
"family": "Borman",
"given": "George A."
}
},
{
"name": {
"family": "Casadio",
"given": "Carolina"
},
"orcid": "0000-0003-1117-2863"
},
{
"name": {
"family": "Casanova",
"given": "V\u0131\u0301ctor"
}
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Rodriguez Cavero",
"given": "Nicole"
},
"orcid": "0000-0001-5256-0278"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f3"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Errando",
"given": "Manel"
},
"orcid": "0000-0002-1853-863X"
},
{
"name": {
"family": "Escudero",
"given": "Juan"
},
"orcid": "0000-0002-4131-655X"
},
{
"name": {
"family": "Garc\u0131\u0301a-Comas",
"given": "Maya"
},
"orcid": "0000-0003-2323-4486"
},
{
"name": {
"family": "Ag\u0131\u0301s-Gonz\u00e1lez",
"given": "Beatriz"
},
"orcid": "0000-0001-7702-8931"
},
{
"name": {
"family": "Husillos",
"given": "C\u00e9sar"
},
"orcid": "0000-0001-8286-5443"
},
{
"name": {
"family": "Jormanainen",
"given": "Jenni"
},
"orcid": "0000-0003-4519-7751"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kagitani",
"given": "Masato"
},
"orcid": "0000-0002-4115-7122"
},
{
"name": {
"family": "Kopatskaya",
"given": "Evgenia N."
},
"orcid": "0000-0001-9518-337X"
},
{
"name": {
"family": "Kravtsov",
"given": "Vadim"
},
"orcid": "0000-0002-7502-3173"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Lindfors",
"given": "Elina"
},
"orcid": "0000-0002-9155-6199"
},
{
"name": {
"family": "Larionova",
"given": "Elena G."
},
"orcid": "0000-0002-2471-6500"
},
{
"name": {
"family": "Madejski",
"given": "Grzegorz M."
}
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marchini",
"given": "Alessandro"
},
"orcid": "0000-0003-3779-6762"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Morozova",
"given": "Daria A."
},
"orcid": "0000-0002-9407-7804"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"id": "Masiero-Joseph-R",
"name": {
"family": "Masiero",
"given": "Joseph R."
},
"orcid": "0000-0003-2638-720X"
},
{
"id": "Mawet-D",
"name": {
"family": "Mawet",
"given": "Dimitri"
},
"orcid": "0000-0002-8895-4735"
},
{
"name": {
"family": "Middei",
"given": "Riccardo"
},
"orcid": "0000-0001-9815-9092"
},
{
"name": {
"family": "Millar-Blanchaer",
"given": "Maxwell A."
},
"orcid": "0000-0001-6205-9233"
},
{
"name": {
"family": "Myserlis",
"given": "Ioannis"
},
"orcid": "0000-0003-3025-9497"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Nilsson",
"given": "Kari"
},
"orcid": "0000-0002-1445-8683"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Pacciani",
"given": "Luigi"
},
"orcid": "0000-0001-6897-5996"
},
{
"name": {
"family": "Paggi",
"given": "Alessandro"
},
"orcid": "0000-0002-5646-2410"
},
{
"id": "Panopoulou-Georgia-V",
"name": {
"family": "Panopoulou",
"given": "Georgia V."
},
"orcid": "0000-0001-7482-5759"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sakanoi",
"given": "Takeshi"
},
"orcid": "0000-0002-7146-9020"
},
{
"name": {
"family": "Savchenko",
"given": "Sergey S."
},
"orcid": "0000-0003-4147-3851"
},
{
"name": {
"family": "Sota",
"given": "Alfredo"
},
"orcid": "0000-0002-9404-6952"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Tinyanont",
"given": "Samaporn"
}
},
{
"name": {
"family": "Vasilyev",
"given": "Andrey A."
},
"orcid": "0000-0002-8293-0214"
},
{
"name": {
"family": "Weaver",
"given": "Zachary R."
},
"orcid": "0000-0001-6314-0690"
},
{
"name": {
"family": "Zhovtan",
"given": "Alexey V."
}
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Ng",
"given": "Stephen C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Sgr\u00f3",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicolas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey"
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
}
]
},
"title": "Polarized blazar X-rays imply particle acceleration in shocks",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Multidisciplinary",
"note": "I.L. thanks the Kavli Institute for the Physics and Mathematics of the Universe for their hospitality while this paper was written. We thank A. Veledina for discussions that helped improve this work. I.L. was supported by the JSPS postdoctoral short-term fellowship programme. The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). Data from the Steward Observatory spectropolarimetric monitoring project were used. This programme is supported by Fermi Guest Investigator grants NNX08AW56G, NNX09AU10G, NNX12AO93G and NNX15AU81G. This research has made use of data from the RoboPol programme, a collaboration between Caltech, the University of Crete, the Institute of Astrophysics-Foundation for Research and Technology (IA-FORTH), the Inter-University Centre for Astronomy and Astrophysics (IUCAA), the Max Planck Institute for Radioastronomy (MPIfR) and the Nicolaus Copernicus University, which was conducted at Skinakas Observatory in Crete, Greece. The Instituto Astrof\u00edsica Andaluc\u00eda (IAA)-Consejo Superior de Investigaciones Cient\u00edficas (CSIC) co-authors acknowledge financial support from the Spanish Ministerio de Ciencia e Innovacion (MCINN) through the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrofisica de Andalucia-CSIC (SEV-2017-0709). Acquisition and reduction of the POLAMI and Monitoring AGN with Polarimetry at the Calar Alto Telescopes (MAPCAT) data were supported in part by Ministerio de Ciencia e Innovaci\u00f3n (MICINN) through grants AYA2016-80889-P and PID2019-107847RB-C44. The POLAMI observations were carried out at the IRAM 30\u2009m Telescope. IRAM is supported by the National Institute of Sciences of the Universe (INSU)/Scientific Research National Center (CNRS) (France), Max-Planck-Gesellschaft (MPG) (Germany) and Instituto Geogr\u00e1fico Nacional (IGN) (Spain). The research at Boston University was supported in part by National Science Foundation grant AST-2108622, NASA Fermi Guest Investigator grant 80NSSC21K1917 and NASA Swift Guest Investigator grant 80NSSC22K0537. This study uses observations conducted with the 1.8\u2009m Perkins Telescope Observatory in Arizona (USA), which is owned and operated by Boston University. Based on observations obtained at the Hale Telescope, Palomar Observatory as part of a continuing collaboration between the California Institute of Technology, NASA/Jet Propulsion Laboratory (JPL), Yale University and the National Astronomical Observatories of China. This research made use of Photutils, an Astropy package for detection and photometry of astronomical sources60. G.V.P. acknowledges support by NASA through the NASA Hubble Fellowship grant no. HST-HF2-51444.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Based on observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku and the University of Oslo, representing Denmark, Finland and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The data presented here were obtained (in part) with ALFOSC, which is provided by the Instituto de Astrofisica de Andalucia (IAA) under a joint agreement with the University of Copenhagen and the Nordic Optical Telescope. V.K. thanks the Vilho, Yrj\u00f6 and Kalle V\u00e4is\u00e4l\u00e4 Foundation. J.J. was supported by Academy of Finland project 320085. E.L. was supported by Academy of Finland projects 317636 and 320045. Part of the French contribution was supported by the CNRS and the French spatial agency (CNES). Based on observations collected at the Observatorio de Sierra Nevada, owned and operated by the Instituto de Astrofisica de Andalucia (IAA-CSIC). Based on observations collected at the Centro Astronomico Hispano-Aleman (CAHA), proposal 22A-2.2-015, operated jointly by Junta de Andalucia and Consejo Superior de Investigaciones Cientificas (IAA-CSIC).\n\nOpen access funding provided by University of Turku (UTU) including Turku University Central Hospital.",
"abstract": "Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1\u2009TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization\u2014the only range available until now\u2014probe extended regions of the jet containing particles that left the acceleration site days to years earlier, and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree \u03a0X of around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock.",
"date": "2022-11-24",
"date_type": "published",
"publication": "Nature",
"volume": "611",
"number": "7937",
"publisher": "Nature Publishing Group",
"pagerange": "677-681",
"id_number": "CaltechAUTHORS:20221212-796684400.32",
"issn": "0028-0836",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221212-796684400.32",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Japan Society for the Promotion of Science (JSPS)"
},
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "NASA",
"grant_number": "NNX08AW56G"
},
{
"agency": "NASA",
"grant_number": "NNX09AU10G"
},
{
"agency": "NASA",
"grant_number": "NNX12AO93G"
},
{
"agency": "NASA",
"grant_number": "NNX15AU81G"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "AYA2016-80889-P"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PID2019-107847RB-C44"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Max-Planck-Gesellschaft (MPG)"
},
{
"agency": "Instituto Geogr\u00e1fico Nacional (IGN)"
},
{
"agency": "NSF",
"grant_number": "AST-2108622"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1917"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K0537"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51444.001-A"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "Vilho Foundation"
},
{
"agency": "Yrj\u00f6 Foundation"
},
{
"agency": "Kalle V\u00e4is\u00e4l\u00e4 Foundation"
},
{
"agency": "Academy of Finland",
"grant_number": "320085"
},
{
"agency": "Academy of Finland",
"grant_number": "317636"
},
{
"agency": "Academy of Finland",
"grant_number": "320045"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "University of Turku"
},
{
"agency": "Turku University Central Hospital"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Infrared-Processing-and-Analysis-Center-(IPAC)"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41586-022-05338-0",
"pmcid": "PMC9684068",
"pub_year": "2022",
"author_list": "Liodakis, Ioannis; Marscher, Alan P.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/npdzz-q5b30",
"eprint_id": 118642,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:13:27",
"lastmod": "2025-11-20 20:31:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Marshall-Herman-L",
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Ng",
"given": "Mason"
},
"orcid": "0000-0002-0940-6563"
},
{
"name": {
"family": "Rogantini",
"given": "Daniele"
},
"orcid": "0000-0002-5359-9497"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
},
{
"name": {
"family": "Malacaria",
"given": "Christian"
},
"orcid": "0000-0002-0380-0041"
},
{
"name": {
"family": "Agudo",
"given": "Iv\u00e1n"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
},
"orcid": "0000-0002-5106-0463"
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
},
"orcid": "0000-0002-9460-1821"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-8848-1392"
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Monte",
"given": "Ettore Del"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Gesu",
"given": "Laura Di"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Lalla",
"given": "Niccol\u00f2 Di"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Marco",
"given": "Alessandro Di"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
},
"orcid": "0000-0002-4700-4549"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-9522-5453"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
},
"orcid": "0000-0001-6061-3480"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
},
"orcid": "0000-0003-1548-1524"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
},
"orcid": "0000-0003-0411-4606"
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
},
{
"name": {
"family": "Schulz",
"given": "Norbert S."
},
"orcid": "0000-0002-0842-7792"
},
{
"name": {
"family": "Chakrabarty",
"given": "Deepto"
},
"orcid": "0000-0001-8804-8946"
}
]
},
"title": "Observations of 4U 1626\u201367 with the Imaging X-Ray Polarimetry Explorer",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "IXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0 and agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by Istituto Nazionale di Astrofisica (INAF) and Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). Funding for this work was provided in part by contract 80MSFC17C0012 from the MSFC to MIT in support of the IXPE project. Support for this work was provided in part by NASA through the Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 to MIT for support of the Chandra X-Ray Center, which is operated by SAO for and on behalf of NASA under contract NAS8-03060. M.N. also acknowledges support from the NASA NICER program under detector team grant 80NSSC19K1287 and guest observer grant 80NSSC22K1350. S.S.T. and J.P. were supported by Russian Science Foundation grant 20-12-00364 and Academy of Finland grants 333112, 349144, 349373, and 349906. We thank K. C. Gendreau and Z. Arzoumanian for their help in arranging coordinated NICER scheduling of the observations.",
"abstract": "We present measurements of the polarization of X-rays in the 2\u20138 keV band from the pulsar in the ultracompact low-mass X-ray binary 4U 1626\u201367 using data from the Imaging X-Ray Polarimetry Explorer (IXPE). The 7.66 s pulsations were clearly detected throughout the IXPE observations as well as in the NICER soft X-ray observations, which we used as the basis for our timing analysis and to constrain the spectral shape over the 0.4\u201310 keV energy band. Chandra HETGS high-resolution X-ray spectra were also obtained near the times of the IXPE observations for firm spectral modeling. We found an upper limit on the pulse-averaged linear polarization of <4% (at 95% confidence). Similarly, there was no significant detection of polarized flux in pulse phase intervals when subdividing the bandpass by energy. However, spectropolarimetric modeling over the full bandpass in pulse phase intervals provided a marginal detection of polarization of the power-law spectral component at the 4.8% \u00b1 2.3% level (90% confidence). We discuss the implications concerning the accretion geometry onto the pulsar, favoring two-component models of the pulsed emission.",
"date": "2022-11-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "940",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 70",
"id_number": "CaltechAUTHORS:20230103-818063100.52",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230103-818063100.52",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN 2021-43-HH.0"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "NASA",
"grant_number": "80MSFC17C0012"
},
{
"agency": "Smithsonian Astrophysical Observatory",
"grant_number": "SV3-73016"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1287"
},
{
"agency": "NASA",
"grant_number": "80NSSC22K1350"
},
{
"agency": "Russian Science Foundation",
"grant_number": "20-12-00364"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
},
{
"agency": "Academy of Finland",
"grant_number": "349144"
},
{
"agency": "Academy of Finland",
"grant_number": "349373"
},
{
"agency": "Academy of Finland",
"grant_number": "349906"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac98c2",
"pub_year": "2022",
"author_list": "Marshall, Herman L.; Ng, Mason; et al."
},
{
"id": "https://authors.library.caltech.edu/records/q5fs0-fwh71",
"eprint_status": "archive",
"datestamp": "2023-10-25 20:51:20",
"lastmod": "2025-11-20 23:49:18",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"name": {
"family": "Taverna",
"given": "Roberto"
},
"orcid": "0000-0002-1768-618X"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
}
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Zane",
"given": "Silvia"
},
"orcid": "0000-0001-5326-880X"
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Gonz\u00e1lez-Caniulef",
"given": "Denis"
},
"orcid": "0000-0001-5848-0180"
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"id": "Calazzo-Ilaria",
"name": {
"family": "Caiazzo",
"given": "Ilaria"
},
"orcid": "0000-0002-4770-5388"
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f2"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Errando",
"given": "Manel"
},
"orcid": "0000-0002-1853-863X"
},
{
"name": {
"family": "Gau",
"given": "Ephraim"
},
"orcid": "0000-0002-5250-2710"
},
{
"name": {
"family": "K\u0131rm\u0131z\u0131bayrak",
"given": "Demet"
},
"orcid": "0000-0003-2675-740X"
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "Negro",
"given": "Michela"
},
"orcid": "0000-0002-6548-5622"
},
{
"name": {
"family": "Ng",
"given": "Mason"
},
"orcid": "0000-0002-0940-6563"
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
},
"orcid": "0000-0002-8801-6263"
},
{
"name": {
"family": "Uchiyama",
"given": "Keisuke"
},
"orcid": "0000-0002-7752-9389"
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Agudo",
"given": "Ivan"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
}
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
}
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
}
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
},
"orcid": "0000-0002-0901-2097"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
}
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f2"
}
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "Costa",
"given": "Enrico"
}
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
}
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
},
"orcid": "0000-0002-5614-5028"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
}
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
},
"orcid": "0000-0001-6096-6710"
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
}
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garcia",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
},
"orcid": "0000-0002-5881-2445"
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
}
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
}
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
},
"orcid": "0000-0002-0110-6136"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-2049-2690"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
}
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "Stephen C.-Y."
},
"orcid": "0000-0002-5847-2612"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
},
"orcid": "0000-0002-1868-8056"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
},
"orcid": "0000-0001-6194-4601"
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
}
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Pilia",
"given": "Maura"
}
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
}
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
}
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
},
"orcid": "0000-0003-0411-4243"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
}
},
{
"name": {
"family": "Sgr\u00f2",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
}
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
},
"orcid": "0000-0003-0802-3453"
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
},
"orcid": "0000-0002-9443-6774"
},
{
"name": {
"family": "Thomas",
"given": "Nicholas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
}
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Vink",
"given": "Jacco"
}
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
}
},
{
"name": {
"family": "Xie",
"given": "Fei"
},
"orcid": "0000-0002-0105-5826"
}
]
},
"title": "Polarized x-rays from a magnetar",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Multidisciplinary",
"note": "\u00a9 2022 the authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original US government works. https://www.science.org/about/science-licenses-journal-article-reuse
\n\nWe thank three anonymous referees for helpful and constructive comments that improved the paper. This paper is based on observations made by the IXPE, a joint US and Italian mission. The US contribution to the IXPE mission is supported by NASA and led and managed by the MSFC with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by ASI through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0 and the SSDC with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by INAF and INFN. Data products were provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC) at NASA GSFC.
\n\nR.Ta. and R.Tu. acknowledge financial support from the Italian MUR through grant PRIN 2017LJ39LM. J.H., D.G.-C., I.C., and D.K. acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC), funding reference number 5007110, and the Canadian Space Agency. D.G.-C. is a Canadian Institute for Theoretical Astrophysical (CITA) National Fellow (grant no. CITA 490888-16). E.G. and H.K. acknowledge NASA support under grants 80NSSC18K0264, 80NSSC22K1291, 80NSSC21K1817, and NNX16AC24G. M.Ne. acknowledges support from NASA under award 80GSFC21M0002. T.T. was supported by grant JSPS KAKENHI JP19H05609. F.Mu., J.R., S.B., E.Co., E.D.M., A.D.M., Y.E., S.F., R.F., F.L.M., G.M., M.Pe., A.R., P.So., and A.T. were supported by ASI and INAF under grants ASI-INAF-2017-12-H0 and ASI-INAF-2022-14-HH.0. L.B., L.L., R.Be., R.Bo., A.B., S.Ca., S.M., A.Mar., C.O., M.P.-R., C.S., and G.S. were supported by ASI and INFN under grants ASI-INFN-2017.13-H0 and ASI-INFN-2021-43-HH.0.
\n\nR.Ta., R.Tu., F.Mu., J.H., S.Z., L.B., J.R., and M.C.W. planned the observing campaign. R.Ta., R.Tu., F.Mu., J.H., S.Z., L.B., J.R., D.G.-C., M.B., I.C., N.D.L., E.G., D.K., H.K., M.Ne., M. Ng, N.O., A.Po., T.T., and K.U. analyzed the data. R.Ta., R.Tu., F.Mu., J.H., S.Z., L.B., J.R., D.G.-C., M.B., I.C., A.Po., T.T., and K.U. modeled the data. R.Ta., R.Tu., F.Mu., J.H., S.Z., L.B., J.R., D.G.-C., M.B., and A.Po. wrote the manuscript. V.D. and M.E. served as internal reviewers. All the other authors contributed to the design and science case of the IXPE mission and to the planning of the observations in this paper. All authors provided input and comments on the manuscript.
\n\nThe IXPE observation of 4U 0142+61 is available in the HEASARC IXPE Data Archive https://heasarc.gsfc.nasa.gov/docs/ixpe/archive/ under ObsID 01003299. The IXPE software is available at https://github.com/lucabaldini/ixpeobssim and documented at https://ixpeobssim.readthedocs.io. Our measured polarizations are listed in table S2, and the results of our model fitting are listed in tables S1 and S3.
\n\nThe authors declare there are no competing interests.
\n\nThe code used for the equatorial belt simulation is available at https://github.com/robertotaverna/magMC and archived on Zenodo (31).
",
"abstract": "Magnetars are neutron stars with ultrastrong magnetic fields, which can be observed in x-rays. Polarization measurements could provide information on their magnetic fields and surface properties. We observed polarized x-rays from the magnetar 4U 0142+61 using the Imaging X-ray Polarimetry Explorer and found a linear polarization degree of 13.5 \u00b1 0.8% averaged over the 2\u2013 to 8\u2013kilo\u2013electron volt band. The polarization changes with energy: The degree is 15.0 \u00b1 1.0% at 2 to 4 kilo\u2013electron volts, drops below the instrumental sensitivity ~4 to 5 kilo\u2013electron volts, and rises to 35.2 \u00b1 7.1% at 5.5 to 8 kilo\u2013electron volts. The polarization angle also changes by 90\u00b0 at ~4 to 5 kilo\u2013electron volts. These results are consistent with a model in which thermal radiation from the magnetar surface is reprocessed by scattering off charged particles in the magnetosphere.",
"date": "2022-11-11",
"date_type": "published",
"publication": "Science",
"volume": "378",
"number": "6620",
"publisher": "American Association for the Advancement of Science",
"pagerange": "646-650",
"issn": "0036-8075",
"official_url": "https://authors.library.caltech.edu/records/q5fs0-fwh71",
"funders": {
"items": [
{
"grant_number": "5007110"
},
{},
{
"grant_number": "490888-16"
},
{
"grant_number": "80NSSC18K0264"
},
{
"grant_number": "80NSSC22K1291"
},
{
"grant_number": "80NSSC21K1817"
},
{
"grant_number": "NNX16AC24G"
},
{
"grant_number": "80GSFC21M0002"
},
{
"grant_number": "JP19H05609"
},
{
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"grant_number": "ASI-INAF-2022-14-HH.0"
},
{
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"grant_number": "ASI-INFN-2021-43-HH.0"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "TAPIR"
}
]
},
"doi": "10.1126/science.add0080",
"primary_object": {
"basename": "science.add0080_sm.pdf",
"url": "https://authors.library.caltech.edu/records/q5fs0-fwh71/files/science.add0080_sm.pdf"
},
"pub_year": "2022",
"author_list": "Taverna, Roberto; Turolla, Roberto; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8fvrg-vfn93",
"eprint_id": 118079,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:10:26",
"lastmod": "2025-11-20 22:50:20",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lewin-Collin",
"name": {
"family": "Lewin",
"given": "Collin"
},
"orcid": "0000-0002-8671-1190"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Wilkins-Dan",
"name": {
"family": "Wilkins",
"given": "Dan"
},
"orcid": "0000-0002-4794-5998"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Zhang-Rachel-C",
"name": {
"family": "Zhang",
"given": "Rachel C."
},
"orcid": "0000-0002-2905-9239"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "William N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley"
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Ingram-Adam",
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Lohfink-Anne-M",
"name": {
"family": "Lohfink",
"given": "Anne M."
}
},
{
"id": "Lucchini-Matteo",
"name": {
"family": "Lucchini",
"given": "Matteo"
},
"orcid": "0000-0002-2235-3347"
},
{
"id": "Reynolds-Christopher-S",
"name": {
"family": "Reynolds",
"given": "Christopher S."
},
"orcid": "0000-0002-1510-4860"
},
{
"id": "Tombesi-Francesco",
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"id": "van-der-Klis-Michiel",
"name": {
"family": "van der Klis",
"given": "Michiel"
},
"orcid": "0000-0003-0070-9872"
},
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
}
]
},
"title": "X-Ray Reverberation Mapping of Ark 564 Using Gaussian Process Regression",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "E.K., G.M., and J.A.G. acknowledge support from NASA grant 80NSSC20K0575. J.J. acknowledges support from the Leverhulme Trust, the Isaac Newton Trust, and St Edmund's College, University of Cambridge. A.I. acknowledges support from the Royal Society. G.M. and J.A.G. acknowledge support from NASA grant 80NSSC19K1020. J.A.G. also acknowledges support from the Alexander von Humboldt Foundation. This work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for their support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (nustardas), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). M.K. acknowledges support through an NWO (Nederlandse Organisatie voor Wetenschappelijk Onderzoek) Spinoza grant. C.S.R. thanks the UK Science and Technology Facilities Council (STFC) for support under the Consolidated Grant ST/S000623/1, as well as the European Research Council (ERC) for support under the European Union\u00e2s Horizon 2020 research and innovation program (grant 834203).",
"abstract": "Ark 564 is an extreme high-Eddington narrow-line Seyfert 1 galaxy, known for being one of the brightest, most rapidly variable soft X-ray active galactic nuclei (AGN), and for having one of the lowest temperature coronae. Here, we present a 410 ks NuSTAR observation and two 115 ks XMM-Newton observations of this unique source, which reveal a very strong, relativistically broadened iron line. We compute the Fourier-resolved time lags by first using Gaussian processes to interpolate the NuSTAR gaps, implementing the first employment of multitask learning for application in AGN timing. By simultaneously fitting the time lags and the flux spectra with the relativistic reverberation model reltrans, we constrain the mass at 2.3_(-1.3)^(+2.6) x 10^(6)M_(\u2299), although additional components are required to describe the prominent soft excess in this source. These results motivate future combinations of machine learning, Fourier-resolved timing, and the development of reverberation models.",
"date": "2022-11-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "939",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 109",
"id_number": "CaltechAUTHORS:20221128-494241100.41",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221128-494241100.41",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K0575"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1020"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/S000623/1"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "834203"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Isaac Newton Trust"
},
{
"agency": "St. Edmund's College, University of Cambridge"
},
{
"agency": "Royal Society"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac978f",
"pub_year": "2022",
"author_list": "Lewin, Collin; Kara, Erin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dsar9-nr220",
"eprint_id": 117953,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:08:44",
"lastmod": "2025-11-21 01:32:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walsh-Nathan-E",
"name": {
"family": "Walsh",
"given": "Nathan Elliot"
}
},
{
"name": {
"family": "Akaike",
"given": "Yosui"
},
"orcid": "0000-0002-9489-1515"
},
{
"name": {
"family": "Binns",
"given": "Walter Robert"
},
"orcid": "0000-0001-6110-3407"
},
{
"name": {
"family": "Bose",
"given": "Richard G."
}
},
{
"name": {
"family": "Brandt",
"given": "Terri J."
},
"orcid": "0000-0003-4087-1786"
},
{
"name": {
"family": "Braun",
"given": "Dana L."
}
},
{
"name": {
"family": "Cannady",
"given": "Nicholas W."
},
"orcid": "0000-0003-2916-6955"
},
{
"name": {
"family": "Dowkontt",
"given": "Paul F."
}
},
{
"name": {
"family": "Hams",
"given": "Thomas"
}
},
{
"name": {
"family": "Israel",
"given": "Martin H."
},
"orcid": "0000-0002-8104-208X"
},
{
"name": {
"family": "Krizmanic",
"given": "John F."
}
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "Allan W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "Richard A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "John W."
}
},
{
"name": {
"family": "Murphy",
"given": "Ryan P."
}
},
{
"name": {
"family": "de Nolfo",
"given": "Georgia A."
},
"orcid": "0000-0002-3677-074X"
},
{
"name": {
"family": "Nutter",
"given": "Scott"
},
"orcid": "0000-0002-1794-3836"
},
{
"name": {
"family": "Olevitch",
"given": "Martin A."
}
},
{
"name": {
"family": "Rauch",
"given": "Brian. F."
},
"orcid": "0000-0002-1452-4142"
},
{
"name": {
"family": "Sakai",
"given": "Kenichi"
}
},
{
"name": {
"family": "Sasaki",
"given": "Makoto"
}
},
{
"name": {
"family": "Simburger",
"given": "Garry E."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Ed C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Tatoli",
"given": "Teresa"
}
},
{
"name": {
"family": "Ward",
"given": "John Ennis"
},
"orcid": "0000-0003-1973-0794"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "Mark E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Zober",
"given": "Wolfgang V."
}
}
]
},
"title": "SuperTIGER instrument abundances of galactic cosmic rays for the charge interval 41 \u2a7d Z \u2a7d 56",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Aerospace Engineering; General Earth and Planetary Sciences; Atmospheric Science; Geophysics; Astronomy and Astrophysics",
"note": "This research was supported by NASA under grants NNX09AC17G, NNX14AB25G, NNX15AC23G and 80NSSC20K0405, by the McDonnell Center for the Space Sciences at Washington University, and by the Peggy and Steve Fossett Foundation.\n\nWe thank the NASA Columbia Scientific Balloon Facility, the NASA Balloon Program Office, and the NSF United States Antarctic Program for the excellent and highly professional efforts that resulted in two successful long-duration balloon flights for SuperTIGER.",
"abstract": "We report preliminary elemental abundance results from the 55-day long-duration-balloon flight of SuperTIGER (Super Trans-Iron Galactic Element Recorder) during the 2012\u20132013 austral summer. SuperTIGER measured the relative abundances of Galactic cosmic-ray (GCR) nuclei with high statistical precision and well resolved individual element peaks from \u2081\u2080Ne to \u2084\u2080Zr. SuperTIGER also made exploratory measurements of the relative abundances up to 56Ba. Although the statistics are low for elements heavier than \u2084\u2080Zr, we present, for the first time, relative abundance measurements of charges Z = 41 - 56 with individual element resolution. GCR measurements up to \u2084\u2080Zr support a source acceleration model where supernovae in OB associations preferentially accelerate refractory elements that are more readily embedded in interstellar dust grains than volatiles. In addition, injection into the GCR for both refractory and volatile elements appears to follow a charge dependence consistent with their grain sputtering cross sections. By extending the GCR measurement range past \u2084\u2080Zr, we can begin to further constrain these models.",
"date": "2022-11-01",
"date_type": "published",
"publication": "Advances in Space Research",
"volume": "70",
"number": "9",
"publisher": "Elsevier",
"pagerange": "2666-2673",
"id_number": "CaltechAUTHORS:20221121-712406200.18",
"issn": "0273-1177",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221121-712406200.18",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX09AC17G"
},
{
"agency": "NASA",
"grant_number": "NNX14AB25G"
},
{
"agency": "NASA",
"grant_number": "NNX15AC23G"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0405"
},
{
"agency": "Washington University"
},
{
"agency": "Peggy and Steve Fossett Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1016/j.asr.2022.04.063",
"pub_year": "2022",
"author_list": "Walsh, Nathan Elliot; Akaike, Yosui; et al."
},
{
"id": "https://authors.library.caltech.edu/records/stc0z-6k888",
"eprint_id": 117685,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:03:16",
"lastmod": "2025-11-20 23:01:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Marinucci-Andrea",
"name": {
"family": "Marinucci",
"given": "A."
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Muleri",
"given": "F."
}
},
{
"name": {
"family": "Dovciak",
"given": "M."
}
},
{
"name": {
"family": "Bianchi",
"given": "S."
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Marin",
"given": "F."
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Matt",
"given": "G."
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Ursini",
"given": "F."
},
"orcid": "0000-0001-9442-7897"
},
{
"name": {
"family": "Middei",
"given": "R."
},
"orcid": "0000-0001-9815-9092"
},
{
"name": {
"family": "Marshall",
"given": "H. L."
}
},
{
"name": {
"family": "Baldini",
"given": "L."
}
},
{
"name": {
"family": "Barnouin",
"given": "T."
}
},
{
"name": {
"family": "Cavero Rodriguez",
"given": "N."
}
},
{
"name": {
"family": "De\u00a0Rosa",
"given": "A."
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Di\u00a0Gesu",
"given": "L."
}
},
{
"name": {
"family": "Harper",
"given": "D."
}
},
{
"name": {
"family": "Ingram",
"given": "A."
},
"orcid": "0000-0002-5311-9078"
},
{
"name": {
"family": "Karas",
"given": "V."
}
},
{
"name": {
"family": "Krawczynski",
"given": "H."
}
},
{
"name": {
"family": "Madejski",
"given": "G."
}
},
{
"name": {
"family": "Panagiotou",
"given": "C."
}
},
{
"name": {
"family": "Petrucci",
"given": "P. O."
}
},
{
"name": {
"family": "Podgorny",
"given": "J."
}
},
{
"name": {
"family": "Puccetti",
"given": "S."
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Tombesi",
"given": "F."
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Veledina",
"given": "A."
},
"orcid": "0000-0002-5767-7253"
},
{
"name": {
"family": "Zhang",
"given": "W."
}
},
{
"name": {
"family": "Agudo",
"given": "I."
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "L. A."
},
"orcid": "0000-0002-5037-9034"
},
{
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baumgartner",
"given": "W. H."
}
},
{
"name": {
"family": "Bellazzini",
"given": "R."
}
},
{
"name": {
"family": "Bongiorno",
"given": "S. D."
}
},
{
"name": {
"family": "Bonino",
"given": "R."
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Brez",
"given": "A."
}
},
{
"name": {
"family": "Bucciantini",
"given": "N."
}
},
{
"name": {
"family": "Capitanio",
"given": "F."
}
},
{
"name": {
"family": "Castellano",
"given": "S."
}
},
{
"name": {
"family": "Cavazzuti",
"given": "E."
}
},
{
"name": {
"family": "Ciprini",
"given": "S."
}
},
{
"name": {
"family": "Costa",
"given": "E."
}
},
{
"name": {
"family": "Del\u00a0Monte",
"given": "E."
}
},
{
"name": {
"family": "Di\u00a0Lalla",
"given": "N."
}
},
{
"name": {
"family": "Di\u00a0Marco",
"given": "A."
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Donnarumma",
"given": "I."
}
},
{
"name": {
"family": "Doroshenko",
"given": "V."
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Ehlert",
"given": "S. R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "T."
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Y."
}
},
{
"name": {
"family": "Fabiani",
"given": "S."
}
},
{
"name": {
"family": "Ferrazzoli",
"given": "R."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "S."
}
},
{
"name": {
"family": "Hayashida",
"given": "K."
}
},
{
"name": {
"family": "Heyl",
"given": "J."
}
},
{
"name": {
"family": "Iwakiri",
"given": "W."
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "S. G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Kitaguchi",
"given": "T."
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "J. J."
}
},
{
"name": {
"family": "La\u00a0Monaca",
"given": "F."
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Latronico",
"given": "L."
}
},
{
"name": {
"family": "Liodakis",
"given": "I."
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Maldera",
"given": "S."
}
},
{
"name": {
"family": "Manfreda",
"given": "A."
}
},
{
"name": {
"family": "Marscher",
"given": "A. P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Mitsuishi",
"given": "I."
}
},
{
"name": {
"family": "Mizuno",
"given": "T."
}
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
}
},
{
"name": {
"family": "O'Dell",
"given": "S. L."
}
},
{
"name": {
"family": "Omodei",
"given": "N."
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "C."
}
},
{
"name": {
"family": "Papitto",
"given": "A."
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "G. G."
}
},
{
"name": {
"family": "Peirson",
"given": "A. L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "M."
}
},
{
"name": {
"family": "Pesce-Rollins",
"given": "M."
}
},
{
"name": {
"family": "Pilia",
"given": "M."
}
},
{
"name": {
"family": "Possenti",
"given": "A."
}
},
{
"name": {
"family": "Poutanen",
"given": "J."
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Ramsey",
"given": "B. D."
}
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Ratheesh",
"given": "A."
}
},
{
"name": {
"family": "Romani",
"given": "R. W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Sgr\u0161",
"given": "C."
}
},
{
"name": {
"family": "Slane",
"given": "P. O."
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Soffitta",
"given": "P."
},
"orcid": "0000-0003-1252-4891"
},
{
"name": {
"family": "Spandre",
"given": "G."
}
},
{
"name": {
"family": "Tamagawa",
"given": "T."
}
},
{
"name": {
"family": "Tavecchio",
"given": "F."
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "R."
}
},
{
"name": {
"family": "Tawara",
"given": "Y."
}
},
{
"name": {
"family": "Tennant",
"given": "A. F."
}
},
{
"name": {
"family": "Thomas",
"given": "N. E."
}
},
{
"name": {
"family": "Trois",
"given": "A."
},
"orcid": "0000-0002-3180-6002"
},
{
"name": {
"family": "Tsygankov",
"given": "S. S."
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "R."
}
},
{
"name": {
"family": "Vink",
"given": "J."
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Weisskopf",
"given": "M. C."
}
},
{
"name": {
"family": "Wu",
"given": "K."
},
"orcid": "0000-0002-7568-8765"
},
{
"name": {
"family": "Xie",
"given": "F."
}
},
{
"name": {
"family": "Zane",
"given": "S."
}
}
]
},
"title": "Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "We thank the anonymous referee for her/his comments and suggestions, which greatly improved the clarity of the paper. The IXPE is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC), and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). Part of the French contribution is supported by the Scientific Research National Center (CNRS) and the French spatial agency (CNES). MD, VK, and JP thank for the support from the GACR project 21-06825X and the institutional support from RVO:67985815. IA acknowledges financial support from the Spanish 'Ministerio de Ciencia e Innovaci\u00f3n' (MCINN) through the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrof\u00edsica de Andaluc\u00eda-CSIC (SEV-2017-0709) and through grants AYA2016-80889-P and PID2019-107847RB-C44.",
"abstract": "We report on the first observation of a radio-quiet active galactic nucleus (AGN) in polarized X-rays: the Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed at with the Imaging X-ray Polarimetry Explorer (IXPE) starting on 2022 May 14 for a net observing time of 486 ks, simultaneously with XMM-Newton (58 ks) and NuSTAR (83 ks). A polarization degree \u03a0 smaller than 4.7\u00a0per\u2009cent (at the 99\u00a0per\u2009cent confidence level) is derived in the 2\u20138\u00a0keV energy range, where emission is dominated by the primary component ascribed to the hot corona. The broad-band spectrum, inferred from a simultaneous fit to the IXPE, NuSTAR, and XMM-Newton data, is well reproduced by a power law with photon index \u0393\u00a0= 1.85\u00a0\u00b1\u00a00.01 and a high-energy cutoff E_C\u00a0= 120\u00a0\u00b1\u00a015\u00a0keV. A comparison with Monte Carlo simulations shows that a lamp-post and a conical geometry of the corona are consistent with the observed upper limit, a slab geometry is allowed only if the inclination angle of the system is less than 50\u00b0.",
"date": "2022-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "516",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "5907-5913",
"id_number": "CaltechAUTHORS:20221101-827781300.7",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221101-827781300.7",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "Academy of Sciences of the Czech Republic",
"grant_number": "21-06825X"
},
{
"agency": "Academy of Sciences of the Czech Republic",
"grant_number": "RVO:67985815"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCINN)"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "AYA2016-80889-P"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PID2019-107847RB-C44"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac2634",
"pub_year": "2022",
"author_list": "Marinucci, A.; Muleri, F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mgwnf-r9e24",
"eprint_id": 117820,
"eprint_status": "archive",
"datestamp": "2023-08-22 18:03:37",
"lastmod": "2025-11-20 20:39:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Reynolds-Mark-T",
"name": {
"family": "Reynolds",
"given": "M. T."
},
"orcid": "0000-0003-1621-9392"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Lemon-Cameron",
"name": {
"family": "Lemon",
"given": "C."
},
"orcid": "0000-0003-2456-9317"
}
]
},
"title": "X-ray absorption and reprocessing in the z \u223c 2.5 lensed quasar 2MASS\u2009J1042+1641",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "The authors would like to thank the reviewer for their detailed feedback, which helped to improve the final version of the manuscript. The authors would also like to thank T. Schmidt and T. Treu for providing advance details of their lens modelling. DJW acknowledges support from the Science and Technology Facilities Council (STFC) in the form of an Ernest Rutherford Fellowship (grant ST/N004027/1). The scientific results reported in this paper are based in part on observations made by the NASA's Chandra X-ray Observatory, as well as data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States. This research has also made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by the NASA Jet Propulsion Laboratory (JPL), and has utilized the NUSTARDAS software package, jointly developed by the Space Science Data Centre (SSDC; Italy) and Caltech (USA). For the purpose of open access, the author(s) has applied a Creative Commons Attribution (CC BY) licence to any Author Accepted Manuscript version arising.",
"abstract": "We present new broad-band X-ray observations of the z \u223c 2.5 lensed quasar 2MASS\u2009J1042+1641, combining XMM\u2013Newton, Chandra, and NuSTAR to provide coverage of the X-ray spectrum over the 0.3\u201340\u2009keV bandpass in the observed frame, corresponding to the \u223c1\u2013140\u2009keV band in the rest frame of 2MASS\u2009J1042+1641. The X-ray data show clear evidence for strong (but still Compton-thin) X-ray absorption, NH \u223c 3\u20134 \u00d7 10\u00b2\u00b3\u2009cm\u207b\u00b2\u2060, in addition to significant reprocessing by Compton-thick material that must lie away from our line of sight to the central X-ray source. We test two different interpretations for the latter: first that the reprocessing occurs in a classic active galactic nucleus torus, as invoked in unification models, and second that the reprocessing occurs in the accretion disc. Both models can successfully reproduce the observed spectra, and both imply that the source is viewed at moderately low inclinations (i < 50\u00b0) despite the heavy line-of-sight absorption. Combining the X-ray data with infrared (IR) data from WISE, the results seen from 2MASS\u2009J1042+1641 further support the recent suggestion that large X-ray and IR surveys may together be able to identify good lensed quasar candidates in advance of detailed imaging studies.",
"date": "2022-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "516",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "5997-6008",
"id_number": "CaltechAUTHORS:20221110-429809700.4",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221110-429809700.4",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/N004027/1"
},
{
"agency": "ESA Member States"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac2554",
"pub_year": "2022",
"author_list": "Walton, D. J.; Reynolds, M. T.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/eavhb-9ve02",
"eprint_id": 117571,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:55:46",
"lastmod": "2025-11-20 20:40:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kawamuro-Taiki",
"name": {
"family": "Kawamuro",
"given": "Taiki"
},
"orcid": "0000-0002-6808-2052"
},
{
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"name": {
"family": "Imanishi",
"given": "Masatoshi"
},
"orcid": "0000-0001-6186-8792"
},
{
"name": {
"family": "Mushotzky",
"given": "Richard F."
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Izumi",
"given": "Takuma"
},
"orcid": "0000-0001-9452-0813"
},
{
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"name": {
"family": "Smith",
"given": "Krista Lynne"
},
"orcid": "0000-0001-5785-7038"
},
{
"name": {
"family": "Shimizu",
"given": "Taro"
},
"orcid": "0000-0002-2125-4670"
},
{
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"name": {
"family": "Baba",
"given": "Shunsuke"
},
"orcid": "0000-0002-9850-6290"
},
{
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"name": {
"family": "Chang",
"given": "Chin-Shin"
},
"orcid": "0000-0001-9910-3234"
},
{
"name": {
"family": "Kakkad",
"given": "Darshan"
},
"orcid": "0000-0002-2603-2639"
},
{
"name": {
"family": "Pfeifle",
"given": "Ryan W."
},
"orcid": "0000-0001-8640-8522"
},
{
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"name": {
"family": "Temple",
"given": "Matthew J."
},
"orcid": "0000-0001-8433-550X"
},
{
"name": {
"family": "Ueda",
"given": "Yoshihiro"
},
"orcid": "0000-0001-7821-6715"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Urry",
"given": "Meg"
},
"orcid": "0000-0002-0745-9792"
},
{
"name": {
"family": "Sanders",
"given": "David B."
},
"orcid": "0000-0002-1233-9998"
}
]
},
"title": "BASS XXXII: Studying the Nuclear Millimeter-wave Continuum Emission of AGNs with ALMA at Scales \u2272100-200 pc",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "We thank the reviewer for the useful comments, which helped us improve the quality of the manuscript. We acknowledge support from FONDECYT Postdoctral Fellowships 3200470 (T.K.), 3210157 (A.R.) and 3220516 (M.J.T.), FONDECYT Iniciacion grant 11190831 (C.R.), FONDECYT Regular 1200495 and 1190818 (F.E.B.), ANID BASAL project FB210003 (C.R., F.E.B) and Millennium Science Initiative Program ICN12_009 (F.E.B). T.K., T.I., and M.I. are supported by JSPS KAKENHI grant Nos. JP20K14529, JP20K14531, and JP21K03632, respectively. F.R. acknowledges support from PRIN MIUR 2017 PH3WAT (\"Black hole winds and the baryon life cycle of galaxies\"). K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). M.B. acknowledges support from the YCAA Prize Postdoctoral Fellowship. The scientific results reported in this article are based on data obtained from the Chandra Data Archive. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application packages CIAO. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2012.1.00139.S, #2012.1.00474.S, #2013.1.00525.S, #2013.1.00623.S, #2013.1.01161.S, #2015.1.00086.S, #2015.1.00370.S, #2015.1.00597.S, #2015.1.00872.S, #2015.1.00925.S, #2016.1.00254.S, #2016.1.00839.S, #2016.1.01140.S, #2016.1.01279.S, #2016.1.01385.S, #2016.1.01553.S, #2016.2.00046.S, #2016.2.00055.S, #2017.1.00236.S, #2017.1.00255.S, #2017.1.00395.S, #2017.1.00598.S, #2017.1.00886.L, #2017.1.00904.S, #2017.1.01158.S, #2017.1.01439.S, #2018.1.00006.S, #2018.1.00037.S, #2018.1.00211.S, #2018.1.00248.S, #2018.1.00538.S, #2018.1.00576.S, #2018.1.00581.S, #2018.1.00657.S, #2018.1.00978.S, #2018.1.00986.S, #2018.1.01321.S, #2019.1.00363.S, #2019.1.00763.L, #2019.1.01229.S, #2019.1.01742.S, and #2019.2.00129.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. Data analysis was in part carried out on the Multiwavelength Data Analysis System operated by the Astronomy Data Center (ADC), National Astronomical Observatory of Japan.",
"abstract": "To understand the origin of nuclear (\u2272100 pc) millimeter-wave (mm-wave) continuum emission in active galactic nuclei (AGNs), we systematically analyzed subarcsecond resolution Band-6 (211\u2013275 GHz) Atacama Large Millimeter/submillimeter Array data of 98 nearby AGNs (z < 0.05) from the 70 month Swift/BAT catalog. The sample, almost unbiased for obscured systems, provides the largest number of AGNs to date with high mm-wave spatial resolution sampling (\u223c1\u2013200 pc), and spans broad ranges of 14\u2013150 keV luminosity {40 < log[L\u2081\u2084\u208b\u2081\u2085\u2080/(erg s\u207b\u00b9)] < 45}, black hole mass [5 < log(M_(BH)M_(\u2299)) < 10], and Eddington ratio (-4 < log\u03bb_(Edd) < 2). \nWe find a significant correlation between 1.3 mm (230 GHz) and 14\u2013150 keV luminosities. Its scatter is \u22480.36 dex, and the mm-wave emission may serve as a good proxy of the AGN luminosity, free of dust extinction up to N_H \u223c 10\u00b2\u2076 cm\u207b\u00b2. While the mm-wave emission could be self-absorbed synchrotron radiation around the X-ray corona according to past works, we also discuss different possible origins of the mm-wave emission: AGN-related dust emission, outflow-driven shocks, and a small-scale (<200 pc) jet. The dust emission is unlikely to be dominant, as the mm-wave slope is generally flatter than expected. Also, due to no increase in the mm-wave luminosity with the Eddington ratio, a radiation-driven outflow model is possibly not the common mechanism. Furthermore, we find independence of the mm-wave luminosity on indicators of the inclination angle from the polar axis of the nuclear structure, which is inconsistent with a jet model whose luminosity depends only on the angle.",
"date": "2022-10-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "938",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 87",
"id_number": "CaltechAUTHORS:20221025-983475200.3",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221025-983475200.3",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3200470"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3220516"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "ICN12 009"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP20K14529"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP20K14531"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP21K03632"
},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca (MIUR)",
"grant_number": "PH3WAT"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac8794",
"pub_year": "2022",
"author_list": "Kawamuro, Taiki; Ricci, Claudio; et al."
},
{
"id": "https://authors.library.caltech.edu/records/w8gk5-sbg47",
"eprint_id": 117576,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:55:50",
"lastmod": "2025-11-20 22:42:54",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "M. C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Allen-Steven-W",
"name": {
"family": "Allen",
"given": "S. W."
},
"orcid": "0000-0003-0667-5941"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "T."
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "Cappelluti-Nico",
"name": {
"family": "Cappelluti",
"given": "N."
},
"orcid": "0000-0002-1697-186X"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Irving-Bryen-E",
"name": {
"family": "Irving",
"given": "B. E."
},
"orcid": "0000-0002-4028-3602"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M. J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Mantz-Adam-B",
"name": {
"family": "Mantz",
"given": "A. B."
},
"orcid": "0000-0002-8031-1217"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "K."
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Shaper-Riley-Jane",
"name": {
"family": "Shaper",
"given": "R. J."
}
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D. K."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "B."
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Urry-C-Meg",
"name": {
"family": "Urry",
"given": "C. M."
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Wong-Josephine",
"name": {
"family": "Wong",
"given": "J."
}
}
]
},
"title": "BASS. XXXVI. Constraining the Local Supermassive Black Hole-Halo Connection with BASS DR2 AGNs",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "We thank the anonymous reviewer for helpful comments that improved the paper. M.P. thanks Risa Weschler for helpful discussions. We acknowledge support from NASA through ADAP award NNH16CT03C (M.K.) and NASA-Swift 80NSSC18K0505 (N.C.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, through grant agreement No. 950533 (B.T.); ANID grants CATA-Basal FB210003 (C.R.); Fondecyt Iniciacion grant 11190831 (C.R.); the National Research Foundation of Korea grant NRF-2020R1C1C1005462; and the Japan Society for the Promotion of Science ID: 17321 (K.O.). We acknowledge the work done by the 50+ BASS scientists and Swift-BAT team to make this project possible. The authors gratefully acknowledge the Gauss Centre for Supercomputing e.V. (www.Gauss-center.eu) and the Partnership for Advanced Supercomputing in Europe (PRACE, www.prace-ri.eu) for funding the MultiDark simulation project by providing computing time on the GCS Supercomputer SuperMUC at Leibniz Supercomputing Centre (LRZ, www.lrz.de). The CosmoSim database used in this paper is a service by the Leibniz-Institute for Astrophysics Potsdam (AIP). The MultiDark database was developed in cooperation with the Spanish MultiDark Consolider Project CSD2009-00064.",
"abstract": "We investigate the connection between supermassive black holes (SMBHs) and their host dark matter halos in the local universe using the clustering statistics and luminosity function of active galactic nuclei (AGNs) from the Swift/BAT AGN Spectroscopic Survey (BASS DR2). By forward-modeling AGN activity into snapshot halo catalogs from N-body simulations, we test a scenario in which SMBH mass correlates with dark matter (sub)halo mass for fixed stellar mass. We compare this to a model absent of this correlation, where stellar mass alone determines the SMBH mass. We find that while both simple models are able to largely reproduce the abundance and overall clustering of AGNs, the model in which black hole mass is tightly correlated with halo mass is preferred by the data by 1.8\u03c3. When including an independent measurement on the black hole mass\u2013halo mass correlation, this model is preferred by 4.6\u03c3. We show that the clustering trends with black hole mass can further break the degeneracies between the two scenarios and that our preferred model reproduces the measured clustering differences on one-halo scales between large and small black hole masses. These results indicate that the halo binding energy is fundamentally connected to the growth of SMBHs.",
"date": "2022-10-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "938",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 77",
"id_number": "CaltechAUTHORS:20221025-328264200.2",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221025-328264200.2",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0505"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "MultiDark",
"grant_number": "CSD2009-00064"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac8f8e",
"pub_year": "2022",
"author_list": "Powell, M. C.; Allen, S. W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/me5qz-qs841",
"eprint_id": 117469,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:53:30",
"lastmod": "2025-11-20 23:11:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Maccarone-Thomas-J",
"name": {
"family": "Maccarone",
"given": "Thomas"
},
"orcid": "0000-0003-0976-4755"
},
{
"id": "Huppenkothen-Daniela",
"name": {
"family": "Huppenkothen",
"given": "Daniela"
},
"orcid": "0000-0002-1169-7486"
},
{
"id": "Israel-Gian-Luca",
"name": {
"family": "Israel",
"given": "Gian Luca"
},
"orcid": "0000-0001-5480-6438"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "McKinley"
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "Matthew"
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Pilla-Maura",
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"id": "Poutanen-Juri",
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "Natalie"
}
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "Orbital Decay in M82 X-2",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "The authors wish to thank Victoria Grinberg, W\u0142odek Klu\u017aniak, and Alessandro Ridolfi for useful discussions, and the staff at the NuSTAR Science Operations Center at Caltech for the help in scheduling the observations and the frequent clock-correction file updates, which allowed a prompt analysis of the data. We would also wish to thank the anonymous referee, and the three referees of a previous submission, who provided very insightful feedback that led to a substantial improvement of the quality of the analysis. M.B. was funded in part by PRIN TEC INAF 2019 \"SpecTemPolar!\u2014Timing analysis in the era of high-throughput photon detectors\". M.H. is supported by an ESO fellowship. G.L.I. and M.B. acknowledge funding from the Italian MIUR PRIN grant No. 2017LJ39LM. A.D.J. was funded in part by the Chandra grant No. 803-0000-716015-404H00-6100-2723-4210-40716015HH83121. J.P. was supported by the grant No. 14.W03.31.0021 of the Ministry of Science and Higher Education of the Russian Federation and the Academy of Finland grant No. 333112. D.J.W. acknowledges support from STFC in the form of an Ernest Rutherford Fellowship. H.P.E. acknowledges support under NASA Contract No. NNG08FD60C.\n\nAll the analysis of this paper was done using open-source software, Astropy, Stingray, HENDRICS, PINT, emcee, corner, and scinum, and can easily be verified using the solutions in Tables 1 and 2. The implementation of the Pletsch & Clark (2015) method can be found in the github repository https://github.com/matteobachetti/ell1fit. Figures were produced using the Matplotlib library and the Veusz software. The data used for this work come from the NuSTAR and XMM-Newton missions and are usually held private for one year, and made public on the High Energy Astrophysics Science archive (HEASARC) and the XMM-Newton Science Archive (XSA) afterwards. NuSTAR is a Small Explorer mission led by Caltech and managed by the JPL for NASA's Science Mission Directorate in Washington. NuSTAR was developed in partnership with the Danish Technical University and the Italian Space Agency (ASI). The spacecraft was built by Orbital Sciences Corp., Dulles, Virginia. XMM-Newton is an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.",
"abstract": "M82 X-2 is the first pulsating ultraluminous X-ray source discovered. The luminosity of these extreme pulsars, if isotropic, implies an extreme mass transfer rate. An alternative is to assume a much lower mass transfer rate, but with an apparent luminosity boosted by geometrical beaming. Only an independent measurement of the mass transfer rate can help discriminate between these two scenarios. In this paper, we follow the orbit of the neutron star for 7 yr, measure the decay of the orbit (\u1e56_(orb) / P_(orb) \u2248 -8 \u2022 10\u207b\u2076 yr\u207b\u00b9), and argue that this orbital decay is driven by extreme mass transfer of more than 150 times the mass transfer limit set by the Eddington luminosity. If this is true, the mass available to the accretor is more than enough to justify its luminosity, with no need for beaming. This also strongly favors models where the accretor is a highly magnetized neutron star.",
"date": "2022-10-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "937",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 125",
"id_number": "CaltechAUTHORS:20221017-15547800.31",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221017-15547800.31",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "PRIN-TEC 2019"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "2017LJ39LM"
},
{
"agency": "NASA",
"grant_number": "803-0000-716015-404H00-6100-2723-4210-40716015HH 83121"
},
{
"agency": "Ministry of Science and Higher Education of the Russian Federation",
"grant_number": "14.W03.31.0021"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac8d67",
"pub_year": "2022",
"author_list": "Bachetti, Matteo; Heida, Marianne; et al."
},
{
"id": "https://authors.library.caltech.edu/records/t1q6h-q8p58",
"eprint_id": 117529,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:53:40",
"lastmod": "2025-11-21 18:51:30",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Vink-Jacco",
"name": {
"family": "Vink",
"given": "Jacco"
},
"orcid": "0000-0002-4708-4219"
},
{
"name": {
"family": "Prokhorov",
"given": "Dmitry"
}
},
{
"name": {
"family": "Ferrazzoli",
"given": "Riccardo"
},
"orcid": "0000-0003-1074-8605"
},
{
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"name": {
"family": "Zhou",
"given": "Ping"
},
"orcid": "0000-0002-5683-822X"
},
{
"name": {
"family": "Asakura",
"given": "Kazunori"
}
},
{
"name": {
"family": "Baldini",
"given": "Luca"
},
"orcid": "0000-0002-9785-7726"
},
{
"name": {
"family": "Bucciantini",
"given": "Niccol\u00f3"
}
},
{
"name": {
"family": "Costa",
"given": "Enrico"
},
"orcid": "0000-0003-4925-8523"
},
{
"name": {
"family": "Di Marco",
"given": "Alessandro"
},
"orcid": "0000-0003-0331-3259"
},
{
"name": {
"family": "Heyl",
"given": "Jeremy"
},
"orcid": "0000-0001-9739-367X"
},
{
"name": {
"family": "Marin",
"given": "Fr\u00e9d\u00e9ric"
},
"orcid": "0000-0003-4952-0835"
},
{
"name": {
"family": "Mizuno",
"given": "Tsunefumi"
},
"orcid": "0000-0001-7263-0296"
},
{
"name": {
"family": "Ng",
"given": "C.-Y."
}
},
{
"name": {
"family": "Pesce-Rollins",
"given": "Melissa"
},
"orcid": "0000-0003-1790-8018"
},
{
"name": {
"family": "Ramsey",
"given": "Brian D."
}
},
{
"name": {
"family": "Rankin",
"given": "John"
},
"orcid": "0000-0002-9774-0560"
},
{
"name": {
"family": "Ratheesh",
"given": "Ajay"
}
},
{
"name": {
"family": "Sgr\u00f3",
"given": "Carmelo"
},
"orcid": "0000-0001-5676-6214"
},
{
"name": {
"family": "Soffitta",
"given": "Paolo"
},
"orcid": "0000-0002-7781-4104"
},
{
"name": {
"family": "Swartz",
"given": "Douglas A."
}
},
{
"name": {
"family": "Tamagawa",
"given": "Toru"
}
},
{
"name": {
"family": "Weisskopf",
"given": "Martin C."
},
"orcid": "0000-0002-5270-4240"
},
{
"name": {
"family": "Yang",
"given": "Yi-Jung"
}
},
{
"name": {
"family": "Bellazzini",
"given": "Ronaldo"
},
"orcid": "0000-0002-2469-7063"
},
{
"name": {
"family": "Bonino",
"given": "Raffaella"
},
"orcid": "0000-0002-4264-1215"
},
{
"name": {
"family": "Cavazzuti",
"given": "Elisabetta"
},
"orcid": "0000-0001-7150-9638"
},
{
"name": {
"family": "Costamante",
"given": "Luigi"
}
},
{
"name": {
"family": "Di Lalla",
"given": "Niccol\u00f3"
},
"orcid": "0000-0002-7574-1298"
},
{
"name": {
"family": "Latronico",
"given": "Luca"
},
"orcid": "0000-0002-0984-1856"
},
{
"name": {
"family": "Maldera",
"given": "Simone"
},
"orcid": "0000-0002-0698-4421"
},
{
"name": {
"family": "Manfreda",
"given": "Alberto"
},
"orcid": "0000-0002-0998-4953"
},
{
"name": {
"family": "Massaro",
"given": "Francesco"
},
"orcid": "0000-0002-1704-9850"
},
{
"name": {
"family": "Mitsuishi",
"given": "Ikuyuki"
}
},
{
"name": {
"family": "Omodei",
"given": "Nicola"
},
"orcid": "0000-0002-5448-7577"
},
{
"name": {
"family": "Oppedisano",
"given": "Chiara"
}
},
{
"name": {
"family": "Zane",
"given": "Silvia"
}
},
{
"name": {
"family": "Agudo",
"given": "Ivan"
},
"orcid": "0000-0002-3777-6182"
},
{
"name": {
"family": "Antonelli",
"given": "Lucio A."
}
},
{
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"name": {
"family": "Baumgartner",
"given": "Wayne H."
}
},
{
"name": {
"family": "Bianchi",
"given": "Stefano"
},
"orcid": "0000-0002-4622-4240"
},
{
"name": {
"family": "Bongiorno",
"given": "Stephen D."
}
},
{
"name": {
"family": "Brez",
"given": "Alessandro"
}
},
{
"name": {
"family": "Capitanio",
"given": "Fiamma"
},
"orcid": "0000-0002-6384-3027"
},
{
"name": {
"family": "Castellano",
"given": "Simone"
},
"orcid": "0000-0003-1111-4292"
},
{
"name": {
"family": "Ciprini",
"given": "Stefano"
},
"orcid": "0000-0002-0712-2479"
},
{
"name": {
"family": "De Rosa",
"given": "Alessandra"
},
"orcid": "0000-0001-5668-6863"
},
{
"name": {
"family": "Del Monte",
"given": "Ettore"
},
"orcid": "0000-0002-3013-6334"
},
{
"name": {
"family": "Di Gesu",
"given": "Laura"
}
},
{
"name": {
"family": "Donnarumma",
"given": "Immacolata"
}
},
{
"name": {
"family": "Doroshenko",
"given": "Victor"
},
"orcid": "0000-0001-8162-1105"
},
{
"name": {
"family": "Dov\u010diak",
"given": "Michal"
},
"orcid": "0000-0003-0079-1239"
},
{
"name": {
"family": "Ehlert",
"given": "Steven R."
},
"orcid": "0000-0003-4420-2838"
},
{
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"name": {
"family": "Evangelista",
"given": "Yuri"
}
},
{
"name": {
"family": "Fabiani",
"given": "Sergio"
},
"orcid": "0000-0003-1533-0283"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Gunji",
"given": "Shuichi"
}
},
{
"name": {
"family": "Hayashida",
"given": "Kiyoshi"
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
},
"orcid": "0000-0002-0207-9010"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana G."
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Karas",
"given": "Vladimir"
},
"orcid": "0000-0002-5760-0459"
},
{
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"name": {
"family": "Kolodziejczak",
"given": "Jeffery J."
}
},
{
"name": {
"family": "Krawczynski",
"given": "Henric"
},
"orcid": "0000-0002-1084-6507"
},
{
"name": {
"family": "La Monaca",
"given": "Fabio"
},
"orcid": "0000-0001-8916-4156"
},
{
"name": {
"family": "Liodakis",
"given": "Ioannis"
},
"orcid": "0000-0001-9200-4006"
},
{
"name": {
"family": "Marinucci",
"given": "Andrea"
},
"orcid": "0000-0002-2055-4946"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"name": {
"family": "Matt",
"given": "Giorgio"
},
"orcid": "0000-0002-2152-0916"
},
{
"name": {
"family": "Muleri",
"given": "Fabio"
},
"orcid": "0000-0003-3331-3794"
},
{
"name": {
"family": "O'Dell",
"given": "Stephen L."
}
},
{
"name": {
"family": "Papitto",
"given": "Alessandro"
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Pavlov",
"given": "George G."
},
"orcid": "0000-0002-7481-5259"
},
{
"name": {
"family": "Peirson",
"given": "Abel L."
},
"orcid": "0000-0001-6292-1911"
},
{
"name": {
"family": "Perri",
"given": "Matteo"
}
},
{
"name": {
"family": "Pilia",
"given": "Maura"
},
"orcid": "0000-0001-7397-8091"
},
{
"name": {
"family": "Possenti",
"given": "Andrea"
},
"orcid": "0000-0001-5902-3731"
},
{
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"name": {
"family": "Puccetti",
"given": "Simonetta"
},
"orcid": "0000-0002-2734-7835"
},
{
"name": {
"family": "Romani",
"given": "Roger W."
},
"orcid": "0000-0001-6711-3286"
},
{
"name": {
"family": "Spandre",
"given": "Gloria"
}
},
{
"name": {
"family": "Tavecchio",
"given": "Fabrizio"
},
"orcid": "0000-0003-0256-0995"
},
{
"name": {
"family": "Taverna",
"given": "Roberto"
}
},
{
"name": {
"family": "Tawara",
"given": "Yuzuru"
}
},
{
"name": {
"family": "Tennant",
"given": "Allyn F."
}
},
{
"name": {
"family": "Thomas",
"given": "Nicolas E."
}
},
{
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"name": {
"family": "Trois",
"given": "Alessio"
}
},
{
"name": {
"family": "Tsygankov",
"given": "Sergey"
},
"orcid": "0000-0002-9679-0793"
},
{
"name": {
"family": "Turolla",
"given": "Roberto"
},
"orcid": "0000-0003-3977-8760"
},
{
"name": {
"family": "Wu",
"given": "Kinwah"
}
},
{
"name": {
"family": "Xie",
"given": "Fei"
}
}
]
},
"title": "X-Ray Polarization Detection of Cassiopeia A with IXPE",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC), and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). J.V. and D.P. are supported by funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 101004131 (SHARP). The research at Boston University was supported in part by National Science Foundation grant AST-2108622. We thank Dawoon Kim for kindly providing us with his script for making polar plots of polarization degree and angle. \n\nSoftware: ixpeobsim (Baldini et al. 2022).",
"abstract": "We report on a \u223c5\u03c3 detection of polarized 3\u20136 keV X-ray emission from the supernova remnant Cassiopeia A (Cas A) with the Imaging X-ray Polarimetry Explorer (IXPE). The overall polarization degree of 1.8% \u00b1 0.3% is detected by summing over a large region, assuming circular symmetry for the polarization vectors. The measurements imply an average polarization degree for the synchrotron component of \u223c2.5%, and close to 5% for the X-ray synchrotron-dominated forward shock region. These numbers are based on an assessment of the thermal and nonthermal radiation contributions, for which we used a detailed spatial-spectral model based on Chandra X-ray data. A pixel-by-pixel search for polarization provides a few tentative detections from discrete regions at the \u223c 3\u03c3 confidence level. Given the number of pixels, the significance is insufficient to claim a detection for individual pixels, but implies considerable turbulence on scales smaller than the angular resolution. Cas A's X-ray continuum emission is dominated by synchrotron radiation from regions within \u227210\u00b9\u2077 cm of the forward and reverse shocks. We find that (i) the measured polarization angle corresponds to a radially oriented magnetic field, similar to what has been inferred from radio observations; (ii) the X-ray polarization degree is lower than in the radio band (\u223c5%). Since shock compression should impose a tangential magnetic-field structure, the IXPE results imply that magnetic fields are reoriented within \u223c10\u00b9\u2077 cm of the shock. If the magnetic-field alignment is due to locally enhanced acceleration near quasi-parallel shocks, the preferred X-ray polarization angle suggests a size of 3 \u00d7 10\u00b9\u2076 cm for cells with radial magnetic fields.",
"date": "2022-10-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "938",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 40",
"id_number": "CaltechAUTHORS:20221021-259555500.14",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221021-259555500.14",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNM15AA18C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-OHBI-2017-12-I.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INAF-2017-12-H0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "ASI-INFN-2017.13-H0"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101004131"
},
{
"agency": "NSF",
"grant_number": "AST-2108622"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac8b7b",
"pub_year": "2022",
"author_list": "Vink, Jacco; Prokhorov, Dmitry; et al."
},
{
"id": "https://authors.library.caltech.edu/records/84d9r-p0f91",
"eprint_id": 119368,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:52:18",
"lastmod": "2025-11-20 23:37:39",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Zoglauer-Andreas",
"name": {
"family": "Zoglauer",
"given": "Andreas"
},
"orcid": "0000-0001-9067-3150"
}
]
},
"title": "NuSTAR non-x-ray background",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Mechanical Engineering; Astronomy and Astrophysics; Instrumentation; Control and Systems Engineering; Electronic, Optical and Magnetic Materials",
"note": "CC BY: \u00a9 2023 The Authors. Published by SPIE under a Creative Commons Attribution 4.0 International License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. \n\nThis work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (USA). This material is based upon work supported by NASA under award number 80GSFC21M0002. We thank Dan Stern for constructive comments on this manuscript and to the anonymous referees for their feedback. The authors have no relevant financial interests in the manuscript and no other potential conflicts of interest to disclose. \n\nCode, Data, and Materials Availability. All data for this paper are publicly accessible via the NuSTAR repository in the High Energy Astrophysics Archive at NASA GSFC. Data were processed using the publicly available nustardas FTOOLs as described in this paper. All of the filtering and sorting steps are described in the text. Plots were produced using matpotlib in Python.\n\nPublished - 047001_1.pdf
",
"abstract": "We present an overview of the NuSTAR non x-ray background. This is dominated by proton scattering in the detector and surrounding material as well as activation lines from of material in the detector and its housing. We also discuss contributions from the solar component (when the Sun is active), and the impact of short-lived radiation belts on the NuSTAR background and activation in the detectors.",
"date": "2022-10",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "8",
"number": "4",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"pagerange": "Art. No. 047001",
"id_number": "CaltechAUTHORS:20230221-18374200.17",
"issn": "2329-4124",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-18374200.17",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80GSFC21M0002"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1117/1.jatis.8.4.047001",
"primary_object": {
"basename": "047001_1.pdf",
"url": "https://authors.library.caltech.edu/records/84d9r-p0f91/files/047001_1.pdf"
},
"pub_year": "2022",
"author_list": "Grefenstette, Brian W.; Madsen, Kristin K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ycme0-wxv30",
"eprint_id": 119373,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:52:23",
"lastmod": "2025-11-20 21:45:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Mandigo-Stoba-Milan-Sharma",
"name": {
"family": "Mandigo-Stoba",
"given": "Milan Sharma"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Cook-W-R",
"name": {
"family": "Cook",
"given": "Walter R., III"
}
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
}
]
},
"title": "Properties of Redlen cadmium zinc telluride with respect to x-ray spectroscopy",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Mechanical Engineering; Astronomy and Astrophysics; Instrumentation; Control and Systems Engineering; Electronic, Optical and Magnetic Materials",
"note": "\u00a9 2022 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nWe would like to thank the anonymous reviewers for their suggestions, which have significantly improved the quality of this work. This work was supported by NASA (Grant No. NNX13AC55G). Milan Sharma Mandigo-Stoba also acknowledges support from the Larson Fellowship via the Caltech Summer Undergraduate Research Fellowships program. To the best of our knowledge, there exist no conflicts of interest with regards to this manuscript.\n\nPublished - 046002_1.pdf
",
"abstract": "We present a study of a sample pixelated cadmium zinc telluride (CZT) detector using CZT purchased from Redlen Technologies. We demonstrate that the material shows good uniformity across the 2 cm \u00d7 2 cm \u00d7 3 mm crystal in terms of leakage current, gain, and spectral resolution. We find that the detector produces very good spectral resolution for energies up to at least 105 keV, achieving a full-width at half-maxima of 450 eV at 14 keV up to 880 eV at 105 keV using only single-pixel events. Though our analysis of spectra including multiple-pixel events is somewhat limited, we also produce a spectrum including events in which photon energy is deposited across two adjacent pixels. We find that this degrades the energy resolution by up to 30%, but this result can likely be improved using more rigorous calibrations. Additionally, we investigate depth-of-interaction effects, showing that spectral resolution can be improved by 3% to 7% for energies between 86 and 105 keV by removing events beyond a certain depth. Performing this cut reduces efficiency, removing 13% to 21% of photons from the resulting spectral lines.",
"date": "2022-10",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "8",
"number": "4",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"pagerange": "Art. No. .046002",
"id_number": "CaltechAUTHORS:20230221-18374200.20",
"issn": "2329-4124",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-18374200.20",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX13AC55G"
},
{
"agency": "Caltech Summer Undergraduate Research Fellowship (SURF)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1117/1.jatis.8.4.046002",
"primary_object": {
"basename": "046002_1.pdf",
"url": "https://authors.library.caltech.edu/records/ycme0-wxv30/files/046002_1.pdf"
},
"pub_year": "2022",
"author_list": "Pike, Sean N.; Mandigo-Stoba, Milan Sharma; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6fjbs-af018",
"eprint_id": 117032,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:37:10",
"lastmod": "2025-11-20 20:32:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "DeRocco-William",
"name": {
"family": "DeRocco",
"given": "William"
},
"orcid": "0000-0003-1827-9399"
},
{
"id": "Wegsman-Shalma",
"name": {
"family": "Wegsman",
"given": "Shalma"
}
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Huang-Junwu",
"name": {
"family": "Huang",
"given": "Junwu"
},
"orcid": "0000-0001-6007-7315"
},
{
"id": "Van-Tilburg-Ken",
"name": {
"family": "Van Tilburg",
"given": "Ken"
}
}
]
},
"title": "First Indirect Detection Constraints on Axions in the Solar Basin",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "General Physics and Astronomy",
"note": "We thank Iain Hannah, Crystal Kim, and David Smith for discussion regarding NuSTAR data products and instrumental response. We are grateful to Robert Lasenby for sharing preliminary results upon which the production computation in the Supplemental Material [31] is based, as well as many clarifying discussions and comments on the draft. We thank Asimina Arvanitaki and Matthew Johnson for comments on the draft, and Andrea Caputo, Joshua Foster, Cristina Mondino, Benjamin Safdi, Edoardo Vitagliano, and Huacheng Yu for useful conversations. W.\u2009D. is supported by the U.S Department of Energy, Grant No. DE-SC0010107. Research at Perimeter Institute is supported in part by the Government of Canada through the Department of Innovation, Science and Economic Development Canada and by the Province of Ontario through the Ministry of Colleges and Universities. The Center for Computational Astrophysics at the Flatiron Institute is supported by the Simons Foundation.",
"abstract": "Axions with masses of order keV can be produced in great abundance within the Solar core. The majority of Sun-produced axions escape to infinity, but a small fraction of the flux is produced with speeds below the escape velocity. Over time, this process populates a basin of slow-moving axions trapped on bound orbits. These axions can decay to two photons, yielding an observable signature. We place the first\nlimits on this solar basin of axions using recent quiescent solar observations made by the NuSTAR x-ray telescope. We compare three different methodologies for setting constraints, and obtain world-leading limits for axions with masses between 5 and 30 keV, in some cases improving on stellar cooling bounds by more than an order of magnitude in coupling",
"date": "2022-09-02",
"date_type": "published",
"publication": "Physical Review Letters",
"volume": "129",
"number": "10",
"publisher": "American Physical Society",
"pagerange": "Art. No. 101101",
"id_number": "CaltechAUTHORS:20220916-666142000",
"issn": "0031-9007",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220916-666142000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-SC0010107"
},
{
"agency": "Perimeter Institute for Theoretical Physics"
},
{
"agency": "Department of Innovation, Science and Economic Development (Canada)"
},
{
"agency": "Ontario Ministry of Colleges and Universities"
},
{
"agency": "Simons Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1103/physrevlett.129.101101",
"pub_year": "2022",
"author_list": "DeRocco, William; Wegsman, Shalma; et al."
},
{
"id": "https://authors.library.caltech.edu/records/htqqk-vr305",
"eprint_id": 117548,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:34:13",
"lastmod": "2025-11-20 22:57:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
}
]
},
"title": "Effective area calibration of the Nuclear Spectroscopic Telescope Array",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Mechanical Engineering; Astronomy and Astrophysics; Instrumentation; Control and Systems Engineering; Electronic, Optical and Magnetic Materials",
"note": "\u00a9 The Authors. Published by SPIE under a Creative Commons Attribution 4.0 International License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. \n\nThis work was supported under NASA (Contract No. NNG08FD60C), and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (USA). This material is based upon work supported by NASA (award number 80GSFC21M0002). We thank Murray Brightman, Renee Ludlam, Guglielmo Mastroserio, and Riley Connors for performing the case study re-analyses in Sec. 7.2.\n\nPublished - 034003_1.pdf
",
"abstract": "We present here the updated calibration of the Nuclear Spectroscopic Telescope Array, which was performed using data on the Crab accumulated over the last nine years in orbit. The basis for this new calibration contains over 250 ks of focused Crab observations (imaged through the optics) and over 500 ks of stray-light (SL) Crab observations (not imaged through optics). We measured an epoch averaged spectrum of the SL Crab data and define a canonical Crab spectrum of \u0393 = 2.103 \u00b1 0.001 and N = 9.69 \u00b1 0.02 keV\u207b\u00b9 cm\u207b\u00b2\u2009s\u207b\u00b9 at 1 keV, which we use as our calibration standard. This calibration released in the Calibration Data Base update 20211020 provides significant updates to: (1) the detector absorption component, (2) the detector response function, and (3) the effective area vignetting function. The calibration improves agreement between FPMA and FPMB across detectors with a standard deviation of 1.7% for repeat observations between off-axis angles of 1' to 4'. As a consequence of the measured SL observations, the absolute flux of the instrument has increased by 5% to 15%, with 5% below 1' off-axis angle, 10% between 1 and 2', and 15% above 4'.",
"date": "2022-09",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "8",
"number": "3",
"publisher": "Society of Photo-optical Instrumentation Engineers",
"pagerange": "Art. No. 034003",
"id_number": "CaltechAUTHORS:20221024-125854800.17",
"issn": "2329-4124",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221024-125854800.17",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80GSFC21M0002"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1117/1.jatis.8.3.034003",
"primary_object": {
"basename": "034003_1.pdf",
"url": "https://authors.library.caltech.edu/records/htqqk-vr305/files/034003_1.pdf"
},
"pub_year": "2022",
"author_list": "Madsen, Kristin K.; Forster, Karl; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9qza3-jx928",
"eprint_status": "archive",
"datestamp": "2026-03-10 17:54:51",
"lastmod": "2026-03-28 03:48:57",
"type": "conference_item",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Greffe-Timothee",
"name": {
"family": "Greffe",
"given": "Timothee"
},
"orcid": "0000-0003-4594-1827"
},
{
"id": "Smith-R-M",
"name": {
"family": "Smith",
"given": "Roger M."
},
"orcid": "0000-0001-7062-9726"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0003-2992-8024"
},
{
"id": "Hennessy-John-J",
"name": {
"family": "Hennessy",
"given": "John J."
},
"orcid": "0000-0002-0135-0219"
},
{
"id": "Nikzad-Shouleh",
"name": {
"family": "Nikzad",
"given": "Shouleh"
},
"orcid": "0009-0004-1255-1018"
},
{
"id": "Shapiro-Charles-A",
"name": {
"family": "Shapiro",
"given": "Charles A."
},
"orcid": "0000-0002-4405-0013"
}
]
},
"title": "High dynamic range techniques for astronomical applications of CMOS devices",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "CMOS; detectors; algorithms",
"note": "© 2022 SPIE.
",
"abstract": "We present an approach for improving the effective well depth of a CMOS detector for use on a UV space telescope by using a combination of two techniques: a dual-gain readout mode and the use of a multi-exposure HDR algorithm. Non-destructive readout of the detector in a high-gain and a low-gain mode optimizes the dynamic range of a single exposure by taking advantage of the low read noise of the first mode and the high well depth of the second. The dynamic range can be further extended by the addition of a second, shorter exposure to probe the saturated regions of the initial exposure. We find that, for simulations of an SRI CMOS imager we are testing, its initial sensitivity to ~3 orders of magnitude in flux can be improved to a dynamic range of over 5.5 orders of magnitude (equivalent to a difference of ~14 AB magnitudes) by the combination of a 300 second dual-gain exposure and a 3 second low-gain exposure, with a low overhead in additional read time and computational complexity.
",
"date": "2022-08-29",
"date_type": "published",
"publication": "X-Ray, Optical, and Infrared Detectors for Astronomy X",
"publisher": "SPIE",
"place_of_pub": "Bellingham, WA",
"pagerange": "121910G",
"isbn": "9781510653634",
"editors": {
"items": [
{
"name": {
"family": "Holland",
"given": "Andrew D."
}
},
{
"name": {
"family": "Beletic",
"given": "James"
}
}
]
},
"official_url": "https://authors.library.caltech.edu/records/9qza3-jx928",
"local_group": {
"items": [
{
"id": "Palomar-Observatory"
},
{
"id": "Physics-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Physics-Mathematics-and-Astronomy"
}
]
},
"doi": "10.1117/12.2630367",
"pub_year": "2022",
"author_list": "Earnshaw, Hannah P.; Greffe, Timothee; et al."
},
{
"id": "https://authors.library.caltech.edu/records/1azpx-42142",
"eprint_id": 114944,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:19:09",
"lastmod": "2025-11-20 20:43:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "De-Kishalay",
"name": {
"family": "De",
"given": "Kishalay"
},
"orcid": "0000-0002-8989-0542"
},
{
"id": "Mereminskiy-Ilya-A",
"name": {
"family": "Mereminskiy",
"given": "Ilya"
},
"orcid": "0000-0001-8931-1320"
},
{
"id": "Soria-Roberto",
"name": {
"family": "Soria",
"given": "Roberto"
},
"orcid": "0000-0002-4622-796X"
},
{
"id": "Conroy-Charlie",
"name": {
"family": "Conroy",
"given": "Charlie"
},
"orcid": "0000-0002-1590-8551"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Anand-Shreya-G",
"name": {
"family": "Anand",
"given": "Shreya"
},
"orcid": "0000-0003-3768-7515"
},
{
"id": "Ashley-Michael-C-B",
"name": {
"family": "Ashley",
"given": "Michael C. B."
},
"orcid": "0000-0003-1412-2028"
},
{
"id": "Boyer-Martha-L",
"name": {
"family": "Boyer",
"given": "Martha L."
},
"orcid": "0000-0003-4850-9589"
},
{
"id": "Chakrabarty-Deepto",
"name": {
"family": "Chakrabarty",
"given": "Deepto"
},
"orcid": "0000-0001-8804-8946"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Hankins-Matthew-J",
"name": {
"family": "Hankins",
"given": "Matthew J."
},
"orcid": "0000-0001-9315-8437"
},
{
"id": "Hillenbrand-L-A",
"name": {
"family": "Hillenbrand",
"given": "Lynne A."
}
},
{
"id": "Jencson-Jacob-E",
"name": {
"family": "Jencson",
"given": "Jacob E."
},
"orcid": "0000-0001-5754-4007"
},
{
"id": "Karambelkar-Viraj-R",
"name": {
"family": "Karambelkar",
"given": "Viraj"
},
"orcid": "0000-0003-2758-159X"
},
{
"id": "Kasliwal-M-M",
"name": {
"family": "Kasliwal",
"given": "Mansi M."
},
"orcid": "0000-0002-5619-4938"
},
{
"id": "Lau-Ryan-M",
"name": {
"family": "Lau",
"given": "Ryan M."
},
"orcid": "0000-0003-0778-0321"
},
{
"id": "Lutovinov-Alexander-A",
"name": {
"family": "Lutovinov",
"given": "Alexander"
},
"orcid": "0000-0002-6255-9972"
},
{
"id": "Moore-Anna-M",
"name": {
"family": "Moore",
"given": "Anna M."
},
"orcid": "0000-0002-2894-6936"
},
{
"id": "Ng-Mason",
"name": {
"family": "Ng",
"given": "Mason"
},
"orcid": "0000-0002-0940-6563"
},
{
"id": "Panagiotou-Christos",
"name": {
"family": "Panagiotou",
"given": "Christos"
}
},
{
"id": "Pasham-Dheeraj-R",
"name": {
"family": "Pasham",
"given": "Dheeraj R."
},
"orcid": "0000-0003-1386-7861"
},
{
"id": "Semena-Andrey-N",
"name": {
"family": "Semena",
"given": "Andrey"
}
},
{
"id": "Simcoe-Robert-A",
"name": {
"family": "Simcoe",
"given": "Robert"
},
"orcid": "0000-0003-3769-9559"
},
{
"id": "Soon-Jamie",
"name": {
"family": "Soon",
"given": "Jamie"
}
},
{
"id": "Srinivasaragavan-Gokul-P",
"name": {
"family": "Srinivasaragavan",
"given": "Gokul P."
}
},
{
"id": "Travouillon-Tony-D",
"name": {
"family": "Travouillon",
"given": "Tony"
},
"orcid": "0000-0002-7279-3658"
},
{
"id": "Yao-Yuhan",
"name": {
"family": "Yao",
"given": "Yuhan"
},
"orcid": "0000-0001-6747-8509"
}
]
},
"title": "SRGA J181414.6-225604: A New Galactic Symbiotic X-Ray Binary Outburst Triggered by an Intense Mass-loss Episode of a Heavily Obscured Mira Variable",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray surveys; Near infrared astronomy; Symbiotic binary stars; Asymptotic giant branch stars; Bondi accretion; Circumstellar dust",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 March 7; revised 2022 May 15; accepted 2022 May 17; published 2022 August 10. \n\nWe thank the anonymous referee for a careful reading of the manuscript and for providing valuable feedback that helped to improve its contents. We thank T. Maccarone, D. Rogantini, P. Pradhan, R. Remillard, and M Guenther for valuable discussions. We thank the Swift, NICER, and NuSTAR teams for approving the Target of Opportunity observations of the transient. Support for this work was provided by NASA through the NASA Hubble Fellowship grant #HST-HF2-51477.001, awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. \n\nPGIR is generously funded by Caltech, Australian National University, the Mt Cuba Foundation, the Heising-Simons Foundation, and the Bi-national Science Foundation. PGIR is a collaborative project among Caltech, Australian National University, University of New South Wales, Columbia University, and the Weizmann Institute of Science. This work is based on data from the Mikhail Pavlinsky ART-XC X-ray telescope on board the SRG observatory. The SRG observatory was built by Roskosmos in the interests of the Russian Academy of Sciences, represented by its Space Research Institute (IKI) in the framework of the Russian Federal Space Program, with the participation of the Deutsches Zentrum f\u00fcr Luft und Raumfahrt (DLR). The SRG spacecraft was designed, built, launched, and is operated by the Lavochkin Association and its subcontractors. The science data are downlinked via the Deep Space Network Antennae in Bear Lakes, Ussurijsk, and Baykonur, funded by Roskosmos. The ART-XC team thank the Russian Space Agency, the Russian Academy of Sciences, and State Corporation Rosatom, for the support for the SRG project and the ART-XC telescope, and the Lavochkin Association (NPOL) and partners for the creation and operation of the SRG spacecraft (Navigator). This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile. We acknowledge the Visiting Astronomer Facility at the Infrared Telescope Facility, which is operated by the University of Hawaii under Cooperative Agreement no. NNX-08AE38A with the National Aeronautics and Space Administration, Science Mission Directorate, Planetary Astronomy Program. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. \n\nThe work of I.M., A.L., and A.S. was supported by the Russian Science Foundation grant 19-12-00423. R.S. acknowledges grant No. 12073029 from the National Science Foundation of China. C.P. acknowledges financial support from the Swiss National Science Foundation (SNF). \n\nFacilities: ROSAT, INTEGRAL, XMM Newton, SRG: ART-XC, NICER, Swift, NuSTAR, PO: 0.3 m (PGIR), PO: 1.2 m (ZTF), PO: 1.5 m (SED Machine), PO: Hale (DBSP, TripleSpec), PanSTARRS, NEOWISE, IRTF (SpeX), Magellan: Baade (FIRE), SSO: ATT (WiFeS). \n\nSoftware: spextool (Cushing et al. 2004), xtellcor (Vacca et al. 2003), pypeit (Prochaska et al. 2020), nustardas (V2.1), Stingray (V0.3; Bachetti et al. 2021), xspec (Arnaud 1996), emcee (Foreman-Mackey et al. 2013), DUSTY (Ivezic & Elitzur 1997), HEAsoft (v6.29c; HEASARC 2014).\n\nPublished - De_2022_ApJ_935_36.pdf
Accepted Version - 2205.09139.pdf
",
"abstract": "We present the discovery and multiwavelength characterization of SRGA J181414.6-225604, a Galactic hard X-ray transient discovered during the ongoing SRG/ART-XC sky survey. Using data from the Palomar Gattini-IR survey, we identify a spatially and temporally coincident variable infrared (IR) source, IRAS 18111-2257, and classify it as a very-late-type (M7\u2013M8), long-period (1502 \u00b1 24 days), and luminous (M_K \u2248 \u22129.9 \u00b1 0.2) O-rich Mira donor star located at a distance of \u224814.6^(+2.9)_(\u22122.3) kpc. Combining multicolor photometric data over the last \u224825 yr, we show that the IR counterpart underwent a recent (starting \u2248800 days before the X-ray flare) enhanced mass-loss (reaching \u22482.1 \u00d7 10\u207b\u2075 M_\u2299 yr\u207b\u00b9) episode, resulting in an expanding dust shell obscuring the underlying star. Multi-epoch follow-up observations from Swift, NICER, and NuSTAR reveal a \u2248200 day long X-ray outburst reaching a peak luminosity of L_\u2093 \u2248 2.5 \u00d7 10\u00b3\u2076 erg s\u207b\u00b9, characterized by a heavily absorbed (N_H \u2248 6 \u00d7 10\u00b2\u00b2 cm\u207b\u00b2) X-ray spectrum consistent with an optically thick Comptonized plasma. The X-ray spectral and timing behavior suggest the presence of clumpy wind accretion, together with a dense ionized nebula overabundant in silicate material surrounding the compact object. Together, we show that SRGA J181414.6-225604 is a new symbiotic X-ray binary in outburst, triggered by an intense dust-formation episode of a highly evolved donor. Our results offer the first direct confirmation for the speculated connection between enhanced late-stage donor mass loss and the active lifetimes of symbiotic X-ray binaries.",
"date": "2022-08-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "935",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 36",
"id_number": "CaltechAUTHORS:20220526-173308925",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220526-173308925",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51477.001"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "Caltech"
},
{
"agency": "Australian National University"
},
{
"agency": "Mt. Cuba Astronomical Foundation"
},
{
"agency": "Heising-Simons Foundation"
},
{
"agency": "Binational Science Foundation (USA-Israel)"
},
{
"agency": "Roskosmos"
},
{
"agency": "Russian Space Agency"
},
{
"agency": "Russian Academy of Sciences"
},
{
"agency": "RosAtom"
},
{
"agency": "NASA",
"grant_number": "NNX-08AE38A"
},
{
"agency": "Russian Science Foundation",
"grant_number": "19-12-00423"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12073029"
},
{
"agency": "Swiss National Science Foundation (SNSF)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac7c6e",
"primary_object": {
"basename": "2205.09139.pdf",
"url": "https://authors.library.caltech.edu/records/1azpx-42142/files/2205.09139.pdf"
},
"related_objects": [
{
"basename": "De_2022_ApJ_935_36.pdf",
"url": "https://authors.library.caltech.edu/records/1azpx-42142/files/De_2022_ApJ_935_36.pdf"
}
],
"pub_year": "2022",
"author_list": "De, Kishalay; Mereminskiy, Ilya; et al."
},
{
"id": "https://authors.library.caltech.edu/records/yjc84-sw763",
"eprint_id": 115966,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:13:02",
"lastmod": "2025-11-20 20:40:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Assef-Roberto-J",
"name": {
"family": "Assef",
"given": "R. J."
},
"orcid": "0000-0002-9508-3667"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "F. E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Blain-Andrew-W",
"name": {
"family": "Blain",
"given": "A. W."
},
"orcid": "0000-0001-7489-5167"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "D\u00edaz-Santos-Tanio",
"name": {
"family": "D\u00edaz-Santos",
"given": "T."
},
"orcid": "0000-0003-0699-6083"
},
{
"id": "Eisenhardt-P-R-M",
"name": {
"family": "Eisenhardt",
"given": "P. R. M."
}
},
{
"id": "Jun-Hyunsung-David",
"name": {
"family": "Jun",
"given": "H. D."
},
"orcid": "0000-0003-1470-5901"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Tsai-Chao-Wei",
"name": {
"family": "Tsai",
"given": "C.-W."
},
"orcid": "0000-0002-9390-9672"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Wu-Jingwen",
"name": {
"family": "Wu",
"given": "J. W."
},
"orcid": "0000-0001-7808-3756"
}
]
},
"title": "Imaging Polarization of the Blue-excess Hot Dust-obscured Galaxy WISE J011601.41\u2013050504.0",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galaxies; Galaxy evolution; High-redshift galaxies; Quasars; Polarimetry; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 February 18; revised 2022 May 26; accepted 2022 June 11; published 2022 July 28. \n\nWe thank Aleksandar Cikota for helping us with the reduction of the FORS2 imaging polarimetry data and Matthew Temple and Aaron Barth for comments and suggestions that helped improve our work. We also thank the anonymous referee for all of the comments and suggestions on the submitted manuscript. R.J.A. was supported by FONDECYT grant No. 1191124 and ANID BASAL project FB210003. F.E.B. acknowledges support from ANID-Chile BASAL AFB-170002, ACE210002, and FB210003; FONDECYT Regular 1200495 and 1190818; and Millennium Science Initiative Program ICN12_009. H.D.J. was supported by National Research Foundation of Korea (NRF) grant 2022R1C1C2013543 funded by the Ministry of Science and ICT (MSIT) of Korea. C.W.T. acknowledges support from NSFC grant 11973051. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO program 106.218J.001. This research uses data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory (JPL)/California Institute of Technology (Caltech), funded by the National Aeronautics and Space Administration (NASA). Portions of this research were carried out at JPL/Caltech under a contract with NASA. This research made use of Photutils, an Astropy package for detection and photometry of astronomical sources (Bradley et al. 2019). This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 526555. These observations are associated with program 14358. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science.\n\nPublished - Assef_2022_ApJ_934_101.pdf
Accepted Version - 2206.04093.pdf
",
"abstract": "We report on VLT/FORS2 imaging polarimetry observations in the R_(Special) band of WISE J011601.41\u2013050504.0 (W0116\u20130505), a heavily obscured hyperluminous quasar at z = 3.173 classified as a Hot Dust-obscured Galaxy (Hot DOG) based on its mid-IR colors. Recently, Assef et al. identified W0116\u20130505 as having excess rest-frame optical/UV emission and concluded that this excess emission is most likely scattered light from the heavily obscured AGN. We find that the broadband rest-frame UV flux is strongly linearly polarized (10.8% \u00b1 1.9%, with a polarization angle of 74\u00b0 \u00b1 9\u00b0), confirming this conclusion. We analyze these observations in the context of a simple model based on scattering either by free electrons or by optically thin dust, assuming a classical dust torus with polar openings. Both can replicate the degree of polarization and the luminosity of the scattered component for a range of geometries and column densities, but we argue that optically thin dust in the ISM is the more likely scenario. We also explore the possibility that the scattering medium corresponds to an outflow recently identified for W0116\u20130505. This is a feasible option if the outflow component is biconical with most of the scattering occurring at the base of the receding outflow. In this scenario, the quasar would still be obscured even if viewed face-on but might appear as a reddened type 1 quasar once the outflow has expanded. We discuss a possible connection between blue-excess Hot DOGs, extremely red quasars, reddened type 1 quasars, and unreddened quasars that depends on a combination of evolution and viewing geometry.",
"date": "2022-08-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "934",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 101",
"id_number": "CaltechAUTHORS:20220729-722134000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220729-722134000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1191124"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2022R1C1C2013543"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11973051"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NAS-526555"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "NSF"
},
{
"agency": "Participating Institutions"
},
{
"agency": "Department of Energy (DOE)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac77fc",
"primary_object": {
"basename": "2206.04093.pdf",
"url": "https://authors.library.caltech.edu/records/yjc84-sw763/files/2206.04093.pdf"
},
"related_objects": [
{
"basename": "Assef_2022_ApJ_934_101.pdf",
"url": "https://authors.library.caltech.edu/records/yjc84-sw763/files/Assef_2022_ApJ_934_101.pdf"
}
],
"pub_year": "2022",
"author_list": "Assef, R. J.; Bauer, F. E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/pp4av-z8y82",
"eprint_id": 115516,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:03:42",
"lastmod": "2025-11-21 03:00:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "Douglas J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Gallo-Luigi-C",
"name": {
"family": "Gallo",
"given": "Luigi C."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Ubach-Santiago",
"name": {
"family": "Ubach",
"given": "Santiago"
}
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "A NuSTAR and Swift view of the hard state of MAXI J1813\u2212095",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, black hole physics, X-rays: binaries; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nReceived: 19 September 2021. Revision received: 15 May 2022. Accepted: 15 May 2022. Published: 20 May 2022. \n\nThis paper was written during the worldwide COVID-19 pandemic in 2020\u20132022. We acknowledge the hard work of all the health care workers around the world. We would not be able to finish this paper without their protection. JJ acknowledges support from the Leverhulme Trust, the Isaac Newton Trust, and St Edmund's College, University of Cambridge. \n\nDATA AVAILABILITY. All the data can be downloaded from the HEASARC website at https://heasarc.gsfc.nasa.gov. The reflionx and relxill models used in this work are available for downloads at https://www.michaelparker.space/reflionx-models and http://www.sternwarte.uni-erlangen.de/dauser/research/relxill.\n\nPublished - stac1401.pdf
Accepted Version - 2205.08227.pdf
",
"abstract": "We present an analysis of the NuSTAR and Swift spectra of the black hole candidate MAXI\u00a0J1813\u2212095 in a failed-transition outburst in 2018. The NuSTAR observations show evidence of reflected emission from the inner region of the accretion disc. By modelling the reflection component in the spectra, we find a disc inner radius of R\u1d62\u2099 < 7\u2009r\u2089. This result suggests that either a slightly truncated disc or a non-truncated disc forms at a few\u00a0per\u2009cent of the Eddington limit in MAXI\u00a0J1813\u2212095. Our best-fitting reflection models indicate that the geometry of the innermost accretion remains consistent during the period of NuSTAR observations. The spectral variability of MAXI\u00a0J1813\u2212095 from multi-epoch observations is dominated by the variable photon index of the Comptonization emission.",
"date": "2022-08",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "514",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "1952-1960",
"id_number": "CaltechAUTHORS:20220712-629762000",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220712-629762000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Leverhulme Trust"
},
{
"agency": "Isaac Newton Trust"
},
{
"agency": "University of Cambridge"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/stac1401",
"primary_object": {
"basename": "2205.08227.pdf",
"url": "https://authors.library.caltech.edu/records/pp4av-z8y82/files/2205.08227.pdf"
},
"related_objects": [
{
"basename": "stac1401.pdf",
"url": "https://authors.library.caltech.edu/records/pp4av-z8y82/files/stac1401.pdf"
}
],
"pub_year": "2022",
"author_list": "Jiang, Jiachen; Buisson, Douglas J. K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0d2sj-0gy47",
"eprint_id": 115695,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:05:14",
"lastmod": "2025-11-21 01:11:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ranking-Jamie-S",
"name": {
"family": "Rankin",
"given": "Jamie S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Bindi-Veronica",
"name": {
"family": "Bindi",
"given": "Veronica"
}
},
{
"id": "Bykov-Andrei-M",
"name": {
"family": "Bykov",
"given": "Andrei M."
}
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "Alan C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Della-Torre-Stefano",
"name": {
"family": "Della Torre",
"given": "Stefano"
}
},
{
"id": "Florinski-Vladimir",
"name": {
"family": "Florinski",
"given": "Vladimir"
}
},
{
"id": "Heber-Bernd",
"name": {
"family": "Heber",
"given": "Bernd"
}
},
{
"id": "Potgieter-Marius-S",
"name": {
"family": "Potgieter",
"given": "Marius S."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Edward C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Zhang-Ming",
"name": {
"family": "Zhang",
"given": "Ming"
}
}
]
},
"title": "Galactic Cosmic Rays Throughout the Heliosphere and in the Very Local Interstellar Medium",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived: 5 March 2022 / Accepted: 15 June 2022. \n\nPart of a collection: The Heliosphere in the Local Interstellar Medium: Into the Unknown. \n\nJ. Rankin is supported by the NASA Early Career Investigator Program (ECIP), award number 80NSSC21K0456. A.M.B. was supported by the baseline project 0040-2019-0025 of the Ioffe Institute. Some of the A.M.B. modeling was performed at the JSCC RAS and the \"Tornado\" subsystem of the St. Petersburg Polytechnic University super-computing center. B.H. is supported under grant 50 OC 2102 and 50 OC 1704 by the German Bundesministerium f\u00fcr Wirtschaft through the Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR). A.C.C. and E.C.S. were supported by NASA award number NNN12AA01C. \n\nOpen Access funding enabled and organized by Projekt DEAL.\n\nPublished - Rankin2022_Article_GalacticCosmicRaysThroughoutTh.pdf
",
"abstract": "We review recent observations and modeling developments on the subject of galactic cosmic rays through the heliosphere and in the Very Local Interstellar Medium, emphasizing knowledge that has accumulated over the past decade. We begin by highlighting key measurements of cosmic-ray spectra by Voyager, PAMELA, and AMS and discuss advances in global models of solar modulation. Next, we survey recent works related to large-scale, long-term spatial and temporal variations of cosmic rays in different regimes of the solar wind. Then we highlight new discoveries from beyond the heliopause and link these to the short-term evolution of transients caused by solar activity. Lastly, we visit new results that yield interesting insights from a broader astrophysical perspective.",
"date": "2022-08",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "218",
"number": "5",
"publisher": "Springer",
"pagerange": "Art. No. 42",
"id_number": "CaltechAUTHORS:20220720-917424000",
"issn": "0038-6308",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220720-917424000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC21K0456"
},
{
"agency": "Ioffe institute",
"grant_number": "0040-2019-0025"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50 OC 2102"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50 OC 1704"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "Projekt DEAL"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1007/s11214-022-00912-4",
"pmcid": "PMC9287243",
"primary_object": {
"basename": "Rankin2022_Article_GalacticCosmicRaysThroughoutTh.pdf",
"url": "https://authors.library.caltech.edu/records/0d2sj-0gy47/files/Rankin2022_Article_GalacticCosmicRaysThroughoutTh.pdf"
},
"pub_year": "2022",
"author_list": "Rankin, Jamie S.; Bindi, Veronica; et al."
},
{
"id": "https://authors.library.caltech.edu/records/fhk1e-vtj16",
"eprint_id": 116001,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:06:47",
"lastmod": "2025-11-20 20:41:47",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Dage-Kristen-C",
"name": {
"family": "Dage",
"given": "Kristen C."
},
"orcid": "0000-0002-8532-4025"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "McKinley"
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Neilsen-Joey",
"name": {
"family": "Neilsen",
"given": "Joey"
},
"orcid": "0000-0002-8247-786X"
},
{
"id": "Hu-Chin-Ping",
"name": {
"family": "Hu",
"given": "Chin-Ping"
},
"orcid": "0000-0001-8551-2002"
},
{
"id": "Altamirano-Diego",
"name": {
"family": "Altamirano",
"given": "Diego"
},
"orcid": "0000-0002-3422-0074"
},
{
"id": "Bahramian-Arash",
"name": {
"family": "Bahramian",
"given": "Arash"
},
"orcid": "0000-0003-2506-6041"
},
{
"id": "Charles-Philip-A",
"name": {
"family": "Charles",
"given": "Philip A."
}
},
{
"id": "Clarkson-William-I",
"name": {
"family": "Clarkson",
"given": "William I."
},
"orcid": "0000-0002-2577-8885"
},
{
"id": "Haggard-Daryl",
"name": {
"family": "Haggard",
"given": "Daryl"
},
"orcid": "0000-0001-6803-2138"
},
{
"id": "Hickox-Ryan-C",
"name": {
"family": "Hickox",
"given": "Ryan C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Kennea-Jamie-A",
"name": {
"family": "Kennea",
"given": "Jamie"
},
"orcid": "0000-0002-6745-4790"
}
]
},
"title": "Monitoring observations of SMC X-1's excursions (MOOSE)\u2013I. Programme description and initial high state spectral results",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, pulsars: individual: SMC X-1, X-rays: binaries1; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model)\n\nAccepted 2022 June 13. Received 2022 June 11; in original form 2022 April 7. \n\nThe authors thank the anonymous referee for helpful feedback. KCD and DH acknowledge funding from the Natural Sciences and Engineering Research Council of Canada (NSERC), and the Canada Research Chairs (CRC) programme. KCD acknowledges fellowship funding from the McGill Space Institute. DA acknowledges support from the Royal Society. The authors thank Elizabeth Ferrara and the NICER team for their efforts with the observation scheduling. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and NASA's Astrophysics Data System Bibliographic Services, as well as the software packes NUMPY (van der Walt, Colbert & Varoquaux 2011) and MATPLOTLIB (Hunter 2007). \n\nDATA AVAILABILITY. The NICER and XMM\u2013Newton observations are publicly available on HEASARC, and the Swift/BAT (Krimm et al. 2013) light curves can be downloaded from https://swift.gsfc.nasa.gov/results/transients/SMCX-1/\n\nPublished - stac1674.pdf
Accepted Version - 2206.06558.pdf
",
"abstract": "SMC X-1 has exhibited three superorbital period excursions since the onset of X-ray monitoring beginning with the Rossi X-ray Timing Explorer's launch in 1995. TheNeutron star Interior Composition Explorer has recently probed a fourth observed excursion beginning in 2021 with our programme monitoring observations of SMC X-1's excursions (moose). These sensitive new moose data probe different superorbital periods and phases within them. Spectral fits to the high-state continuum during 2021 April to 2022 January show that the intrinsic spectral shapes are characterized by a soft (kT \u223c 0.19\u2009keV) disc component and a hard (\u0393 \u223c 0.7) power-law tail. When the 2021\u20132022 NICER observations, taken during an excursion, are compared to 2016 XMM\u2013Newton observations (outside of an excursion), we find little evidence for intrinsic spectral variability across the high states, but find evidence for a >3\u03c3 change in the absorption, although we caution that there may be calibration differences between the two instruments. Thus, over different lengths of superorbital periods, we see little evidence for intrinsic spectral changes in the high state. Upcoming studies of the pulse profiles may shed light on the mechanism behind the excursions.",
"date": "2022-08",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "514",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "5457-5464",
"id_number": "CaltechAUTHORS:20220801-490192000",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220801-490192000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "Canada Research Chairs Program"
},
{
"agency": "McGill Space Institute"
},
{
"agency": "Royal Society"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac1674",
"pmcid": "PMC8825243",
"primary_object": {
"basename": "2206.06558.pdf",
"url": "https://authors.library.caltech.edu/records/fhk1e-vtj16/files/2206.06558.pdf"
},
"related_objects": [
{
"basename": "stac1674.pdf",
"url": "https://authors.library.caltech.edu/records/fhk1e-vtj16/files/stac1674.pdf"
}
],
"pub_year": "2022",
"author_list": "Dage, Kristen C.; Brumback, McKinley; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kjvma-3xb56",
"eprint_id": 116010,
"eprint_status": "archive",
"datestamp": "2023-08-22 17:07:15",
"lastmod": "2025-11-20 23:45:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Joyce-A.",
"name": {
"family": "Joyce",
"given": "A."
}
},
{
"id": "Licklederer-Stefan",
"name": {
"family": "Licklederer",
"given": "S."
},
"orcid": "0000-0002-3720-4408"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "R. M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Ingram-Adam-R",
"name": {
"family": "Ingram",
"given": "A."
},
"orcid": "0000-0002-5311-9078"
},
{
"id": "Reynolds-Christopher-S",
"name": {
"family": "Reynolds",
"given": "C. S."
},
"orcid": "0000-0002-1510-4860"
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "The effect of returning radiation on relativistic reflection",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, black hole physics, X-rays: general; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model).\n\nReceived: 08 June 2021. Revision received: 02 June 2022. Accepted: 06 June 2022. Published: 15 June 2022. \n\nWe would like to express sincere thanks to the anonymous referee with whom we had a comprehensive and illuminating discourse which allowed us to improve the clarity and veracity of our paper to the current state. TD acknowledges funding by the Deutsches Zentrum f\u00fcr Luft- und Raumfahrt contract 50\u2009QR\u20091903. AI acknowledges support from the Royal Society. AJ acknowledges partial funding from the European Space Agency (ESA) under partnership agreement 4000133194/20/NL/MH/hm between ESA and FAU Erlangen-N\u00fcrnberg. JAG acknowledges support from an Alexander von Humboldt fellowship. We thank John E. Davis for the development of the SLXFIG module used to prepare the figures in this paper. This research has made use of ISIS functions provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/). \n\nDATA AVAILABILITY. The data underlying this article will be shared on reasonable request to the corresponding author.\n\nPublished - stac1593.pdf
Accepted Version - 2206.07973.pdf
",
"abstract": "We study the effect of returning radiation on the shape of the X-ray reflection spectrum in the case of thin accretion discs. We show that the returning radiation mainly influences the observed reflection spectrum for a large black hole spin (a > 0.9) and a compact primary source of radiation close to the black hole at height h < 5r_g, and that it dominates the reflected flux for extreme values of spin and compactness. The main effect of the returning radiation is to increase the irradiating flux on to the outer parts of the accretion disc, leading to stronger reflection and a flatter overall emissivity profile. By analysing simulated observations we show that neglecting returning radiation in existing studies of reflection-dominated sources has likely resulted in overestimating the height of the corona above the black hole. An updated version of the publicly available relxill suite of relativistic reflection models which includes returning radiation is also presented.",
"date": "2022-08",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "514",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3965-3983",
"id_number": "CaltechAUTHORS:20220802-742158000",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220802-742158000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50\u2009QR\u20091903"
},
{
"agency": "Royal Society"
},
{
"agency": "European Space Agency (ESA)",
"grant_number": "4000133194/20/NL/MH/hm"
},
{
"agency": "Alexander von Humboldt Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac1593",
"primary_object": {
"basename": "2206.07973.pdf",
"url": "https://authors.library.caltech.edu/records/kjvma-3xb56/files/2206.07973.pdf"
},
"related_objects": [
{
"basename": "stac1593.pdf",
"url": "https://authors.library.caltech.edu/records/kjvma-3xb56/files/stac1593.pdf"
}
],
"pub_year": "2022",
"author_list": "Dauser, T.; Garc\u00eda, J. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/fqq2d-4xs75",
"eprint_id": 115862,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:56:09",
"lastmod": "2025-11-20 23:06:07",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Masterson-Megan",
"name": {
"family": "Masterson",
"given": "Megan"
},
"orcid": "0000-0003-4127-0739"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "Ciro"
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Kosec-Peter",
"name": {
"family": "Kosec",
"given": "Peter"
},
"orcid": "0000-0003-4511-8427"
},
{
"id": "Remillard-Ronald-A",
"name": {
"family": "Remillard",
"given": "Ronald A."
},
"orcid": "0000-0003-4815-0481"
},
{
"id": "Loewenstein-Michael",
"name": {
"family": "Loewenstein",
"given": "Michael"
},
"orcid": "0000-0002-1661-4029"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Arcavi-Iair",
"name": {
"family": "Arcavi",
"given": "Iair"
},
"orcid": "0000-0001-7090-4898"
}
]
},
"title": "Evolution of a Relativistic Outflow and X-Ray Corona in the Extreme Changing-look AGN 1ES 1927+654",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; High energy astrophysics; Seyfert galaxies; Supermassive black holes; X-ray transient sources; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 March 9; revised 2022 May 23; accepted 2022 June 6; published 2022 July 22. \n\nWe thank the anonymous referee for the helpful comments that improved this manuscript. M.M. thanks Ruancun Li, Christos Panagiotou, and Brenna Mockler for their useful comments and discussions. E.K. thanks Daniel Proga and John Raymond for insightful discussions. M.M. and E.K. acknowledge support from NASA grant 80NSSC21K0661. M.M., E.K., B.T., and I.A. acknowledge support from the MISTI Global Seed Funds and the MIT-Israel Zuckerman STEM Fund. C.R. acknowledges support from the Fondecyt Iniciacion grant 11190831 and ANID BASAL project FB210003. R.R. acknowledges support from NASA grant 80NSSC19K1287. I.A. is a CIFAR Azrieli Global Scholar in the Gravity and the Extreme Universe Program and acknowledges support from that program, from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program (grant agreement No. 852097), from the Israel Science Foundation (grant No. 2752/19), from the United States\u2013Israel Binational Science Foundation (BSF), and from the Israeli Council for Higher Education Alon Fellowship. \n\nFacilities: XMM-Newton - , NuSTAR - , NICER. - \n\nSoftware: XSPEC (Arnaud 1996), Astropy (Astropy Collaboration et al. 2013, 2018), xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), relxill (v1.4.0; Garc\u00eda et al. 2014; Dauser et al. 2014).\n\nPublished - Masterson_2022_ApJ_934_35.pdf
Accepted Version - 2206.05140.pdf
",
"abstract": "1ES 1927+654 is a paradigm-defying active galactic nucleus (AGN) and one of the most peculiar X-ray nuclear transients. In early 2018, this well-known AGN underwent a changing-look event, in which broad optical emission lines appeared and the optical flux increased. Yet, by 2018 July, the X-ray flux had dropped by over two orders of magnitude, indicating a dramatic change in the inner accretion flow. With three years of observations with NICER, XMM-Newton, and NuSTAR, we present the X-ray evolution of 1ES 1927+654, which can be broken down into three phases: (1) an early super-Eddington phase with rapid variability in X-ray luminosity and spectral parameters, (2) a stable super-Eddington phase at the peak X-ray luminosity, and (3) a steady decline back to the pre-outburst luminosity and spectral parameters. For the first time, we witnessed the formation of the X-ray corona, as the X-ray spectrum transitioned from thermally dominated to primarily Comptonized. We also track the evolution of the prominent, broad 1 keV feature in the early X-ray spectra and show that this feature can be modeled with blueshifted reflection (z = \u22120.33) from a single-temperature blackbody irradiating spectrum using xillverTDE, a new flavor of the xillver models. Thus, we propose that the 1 keV feature could arise from reflected emission off the base of an optically thick outflow from a geometrically thick, super-Eddington inner accretion flow, connecting the inner accretion flow with outflows launched during extreme accretion events (e.g., tidal disruption events). Lastly, we compare 1ES 1927+654 to other nuclear transients and discuss applications of xillverTDE to super-Eddington accretors.",
"date": "2022-07-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "934",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 35",
"id_number": "CaltechAUTHORS:20220726-998023000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220726-998023000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC21K0661"
},
{
"agency": "Massachusetts Institute of Technology (MIT)"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1287"
},
{
"agency": "Canadian Institute for Advanced Research (CIFAR)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "852097"
},
{
"agency": "Israel Science Foundation",
"grant_number": "2752/19"
},
{
"agency": "Binational Science Foundation (USA-Israel)"
},
{
"agency": "Israeli Council for Higher Education"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac76c0",
"primary_object": {
"basename": "2206.05140.pdf",
"url": "https://authors.library.caltech.edu/records/fqq2d-4xs75/files/2206.05140.pdf"
},
"related_objects": [
{
"basename": "Masterson_2022_ApJ_934_35.pdf",
"url": "https://authors.library.caltech.edu/records/fqq2d-4xs75/files/Masterson_2022_ApJ_934_35.pdf"
}
],
"pub_year": "2022",
"author_list": "Masterson, Megan; Kara, Erin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/v9q1j-11641",
"eprint_id": 115860,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:55:54",
"lastmod": "2025-11-21 00:45:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "M. C."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "J. A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"id": "Coughenour-Benjamin-M",
"name": {
"family": "Coughenour",
"given": "B. M."
},
"orcid": "0000-0003-0870-6465"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "G."
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Wik-Daniel",
"name": {
"family": "Wik",
"given": "D."
},
"orcid": "0000-0001-9110-2245"
},
{
"id": "Krivonos-Roman-A",
"name": {
"family": "Krivonos",
"given": "R."
},
"orcid": "0000-0003-2737-5673"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "A. D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "StrayCats. II. An Updated Catalog of NuSTAR Stray Light Observations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray surveys; Astrophysical black holes; Neutron stars; Low-mass x-ray binary stars; High mass x-ray binary stars; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 April 29; revised 2022 June 10; accepted 2022 June 20; published 2022 July 26. \n\nSupport for this work was provided by NASA through the NASA Hubble Fellowship grant No. HST-HF2-51440.001 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. This work was additionally supported by NASA under grant No. 80NSSC19K1023 issued through the NNH18ZDA001N Astrophysics Data Analysis Program (ADAP). This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Ludlam_2022_ApJ_934_59.pdf
Accepted Version - 2206.09930.pdf
",
"abstract": "We present an updated catalog of StrayCats (a catalog of NuSTAR stray light observations of X-ray sources) that includes nearly 18 additional months of observations. StrayCats v2 has an added 53 sequence IDs, 106 rows, and three new identified stray light (SL) sources in comparison to the original catalog. The total catalog now has 489 unique sequence IDs, 862 entries, and 83 confirmed StrayCats sources. Additionally, we provide new resources for the community to gauge the utility and spectral state of the source in a given observation. We have created long-term light curves for each identified SL source using MAXI and Swift/BAT data when available. Further, source extraction regions for 632 identified SL observations were created and are available to the public. In this paper we present an overview of the updated catalog and new resources for each identified StrayCats SL source.",
"date": "2022-07-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "934",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 59",
"id_number": "CaltechAUTHORS:20220726-997906000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220726-997906000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1023"
},
{
"agency": "NASA",
"grant_number": "NNH18ZDA001N"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac7b27",
"primary_object": {
"basename": "2206.09930.pdf",
"url": "https://authors.library.caltech.edu/records/v9q1j-11641/files/2206.09930.pdf"
},
"related_objects": [
{
"basename": "Ludlam_2022_ApJ_934_59.pdf",
"url": "https://authors.library.caltech.edu/records/v9q1j-11641/files/Ludlam_2022_ApJ_934_59.pdf"
}
],
"pub_year": "2022",
"author_list": "Ludlam, R. M.; Grefenstette, B. W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z8n7k-1mg98",
"eprint_id": 115861,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:56:00",
"lastmod": "2025-11-21 18:49:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "Matthew J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "Timothy P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "The Variability Behavior of NGC 925 ULX-3",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Ultraluminous x-ray sources; X-ray sources; Neutron stars; Accretion; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 May 10; revised 2022 June 14; accepted 2022 June 15; published 2022 July 25. \n\nWe thank our anonymous referee for useful suggestions to improve this paper. We wish to thank Dan Stern for useful comments on this work. This work was supported by NASA grants 80NSSC20K1496 and 80NSSC21K0873, as well as by NASA contract NNG08FD60C. T.P.R. acknowledges funding from STFC consolidated grant ST/000244/1. \n\nWe wish to thank the Swift PI, Brad Cenko, for approving the target-of-opportunity requests we made to monitor NGC 925. We also wish to thank the NuSTAR PI, Fiona Harrison, for approving the DDT request to observe NGC 925 ULX-3 in 2019 December. The scientific results reported in this article are based on observations made by XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA; observations by the NuSTAR mission, a project led by the California Institute of Technology, managed by JPL, and funded by NASA; and observations by the Swift mission, as well as public data from the Swift data archive provided by the UK Swift Science Data Centre at the University of Leicester. We thank the observing teams for these missions for carrying out these observations. \n\nFacilities: XMM - Newton X-Ray Multimirror Mission satellite, CXO - Chandra X-ray Observatory satellite, Swift(XRT) - Swift Gamma-Ray Burst Mission, NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission \n\nSoftware: astropy (Astropy Collaboration et al. 2013), CIAO (Fruscione et al. 2006), FTOOLS (Nasa High Energy Astrophysics Science Archive Research Center (Heasarc), 2014), XMM-Newton SAS, PIMMS, HENDRICS (Bachetti 2018; Huppenkothen et al. 2019).\n\nPublished - Earnshaw_2022_ApJ_934_42.pdf
Accepted Version - 2206.08397.pdf
",
"abstract": "We report the results of a 2019\u20132021 monitoring campaign with Swift and associated target-of-opportunity observations with XMM-Newton and NuSTAR, examining the spectral and timing behavior of the highly variable ultraluminous X-ray source (ULX) NGC 925 ULX-3. We find that the source exhibits a 127\u2013128-day periodicity, with fluxes typically ranging from 1 \u00d7 10\u207b\u00b9\u00b3 to 8 \u00d7 10\u207b\u00b9\u00b3 erg s\u207b\u00b9 cm\u207b\u00b2. We do not find strong evidence for a change in period over the time that NGC 925 ULX-3 has been observed, although the source may have been in a much lower flux state when first observed with Chandra in 2005. We do not detect pulsations, and we place an upper limit on the pulsed fraction of \u223c40% in the XMM-Newton band, consistent with some previous pulsation detections at low energies in other ULXs. The source exhibits a typical ULX spectrum that turns over in the NuSTAR band and can be fitted using two thermal components. These components have a high temperature ratio that may indicate the lack of extreme inner disk truncation by a magnetar-level magnetic field. We examine the implications for a number of different models for superorbital periods in ULXs, finding that a neutron star with a magnetic field of \u223c10\u00b9\u00b2 G may be plausible for this source. The future detection of pulsations from this source would allow for the further testing and constraining of such models.",
"date": "2022-07-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "934",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 42",
"id_number": "CaltechAUTHORS:20220726-997967000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220726-997967000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K1496"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0873"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/000244/1"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ac79b0",
"primary_object": {
"basename": "2206.08397.pdf",
"url": "https://authors.library.caltech.edu/records/z8n7k-1mg98/files/2206.08397.pdf"
},
"related_objects": [
{
"basename": "Earnshaw_2022_ApJ_934_42.pdf",
"url": "https://authors.library.caltech.edu/records/z8n7k-1mg98/files/Earnshaw_2022_ApJ_934_42.pdf"
}
],
"pub_year": "2022",
"author_list": "Earnshaw, Hannah P.; Brightman, Murray; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8tb3c-4hs70",
"eprint_id": 115773,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:49:00",
"lastmod": "2025-11-21 03:13:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mitchell-John-Grant",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "de-Nolfo-Georgia-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mays-M-L",
"name": {
"family": "Mays",
"given": "M. L."
},
"orcid": "0000-0001-9177-8405"
},
{
"id": "McNutt-R-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Odstrcil-Dusan",
"name": {
"family": "Odstrcil",
"given": "D."
},
"orcid": "0000-0001-5114-9911"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
}
]
},
"title": "First Measurements of Jovian Electrons by Parker Solar Probe/IS\u2299IS within 0.5 au of the Sun",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Interplanetary particle acceleration; Solar energetic particles; Corotating streams; Interplanetary magnetic fields; Heliosphere; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 April 20; revised 2022 June 1; accepted 2022 June 2; published 2022 July 13. \n\nWe acknowledge the support of NASA's Parker Solar Probe grant NNN06AA01C. We thank the Parker Solar Probe IS\u2299IS, FIELDS, and SWEAP teams, including the engineers, technicians, administrators, and scientists, who developed the instruments used in this study. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). G.A.deN. acknowledges support from NASA program NNH19ZDA001N-LWS. The authors wish to acknowledge the reviewer for thoughtful comments that served to improve the manuscript and enhance the study.\n\nPublished - Mitchell_2022_ApJ_933_171.pdf
",
"abstract": "Energetic electrons of Jovian origin have been observed for decades throughout the heliosphere, as far as 11 au, and as close as 0.5 au, from the Sun. The treatment of Jupiter as a continuously emitting point source of energetic electrons has made Jovian electrons a valuable tool in the study of energetic electron transport within the heliosphere. We present observations of Jovian electrons measured by the EPI-Hi instrument in the Integrated Science Investigation of the Sun instrument suite on Parker Solar Probe at distances within 0.5 au of the Sun. These are the closest measurements of Jovian electrons to the Sun, providing a new opportunity to study the propagation and transport of energetic electrons to the inner heliosphere. We also find periods of nominal connection between the spacecraft and Jupiter in which expected Jovian electron enhancements are absent. Several explanations for these absent events are explored, including stream interaction regions between Jupiter and Parker Solar Probe and the spacecraft lying on the opposite side of the heliospheric current sheet from Jupiter, both of which could impede the flow of the electrons. These observations provide an opportunity to gain a greater insight into electron transport through a previously unexplored region of the inner heliosphere.",
"date": "2022-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "933",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 171",
"id_number": "CaltechAUTHORS:20220722-768867000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220722-768867000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "NNH19ZDA001N-LWS"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac75ce",
"primary_object": {
"basename": "Mitchell_2022_ApJ_933_171.pdf",
"url": "https://authors.library.caltech.edu/records/8tb3c-4hs70/files/Mitchell_2022_ApJ_933_171.pdf"
},
"pub_year": "2022",
"author_list": "Mitchell, J. G.; Leske, R. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/n1x5b-84369",
"eprint_id": 116012,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:41:01",
"lastmod": "2025-11-20 20:56:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Dong-Yanting",
"name": {
"family": "Dong",
"given": "Yanting"
},
"orcid": "0000-0002-4584-0463"
},
{
"id": "Liu-Zhu-ASTRO",
"name": {
"family": "Liu",
"given": "Zhu"
},
"orcid": "0000-0003-3014-8762"
},
{
"id": "Tuo-Youli",
"name": {
"family": "Tuo",
"given": "Youli"
},
"orcid": "0000-0003-3127-0110"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Gu-Mingyu",
"name": {
"family": "Ge",
"given": "Mingyu"
},
"orcid": "0000-0002-3776-4536"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Cao-Xinwu",
"name": {
"family": "Cao",
"given": "Xinwu"
},
"orcid": "0000-0002-2355-3498"
}
]
},
"title": "Analysis of the reflection spectra of MAXI J1535-571 in the hard and intermediate states",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, black hole physics, methods: data analysis, X-rays: individual: MAXI J1535-571; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model).\n\nReceived: 14 March 2022. Revision received: 11 May 2022. Accepted: 23 May 2022. Published: 30 May 2022. \n\nThe authors thank the referee for the helpful comments to improve our manuscript. This work is supported by the NSFC (11773050, 11833007, 12073023), the science research grants from the China Manned Space Project with NO. CMS-CSST-2021-A06. This work used data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This work also used the data from the Insight-HXMT mission, a project funded by China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). The NuSTAR data and software used in this research are provided by the High Energy Astrophysics Science Archive Research Centre (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. \n\nDATA AVAILABILITY. Data used in this article are publicly available from the NuSTAR mission (https://heasarc.gsfc.nasa.gov/docs/archive.html) and HXMT mission (http://hxmten.ihep.ac.cn).\n\nPublished - stac1466.pdf
Accepted Version - 2205.12058.pdf
",
"abstract": "We report results on the joint-fit of the NuSTAR and HXMT data for the black hole X-ray binary candidate MAXI J1535-571. The observations were obtained in 2017 when the source evolved through the hard, hard-intermediate, and soft-intermediate states over the rising phase of the outburst. After subtracting continuum components, X-ray reflection signatures are clearly showed in those observations. By modelling the relativistic reflection in detail, we find that the inner radius Rin is relatively stable with R_(in) \u2272 1.55R_g during the three states, which implies that the inner radius likely extends to the innermost stable circular orbit even in the bright hard state. When adopting R_(in)\u00a0= R_(ISCO), the spin parameter is constrained to be 0.985_(-0.004)^(+0.002) at 90\u00a0per\u2009cent confidence (statistical only). The best-fitting results reveal that the inclination of the inner accretion disc is \u223c70\u201374 deg, which notably conflicts with the apparent orientation of the ballistic jet (\u226445 deg). In addition, both the photon index and the electron temperature increase during the transition from hard to soft state. It seems that the corona evolves from dense low-temperature in the low/hard state to tenuous high-temperature after the state transition, which indicates that the state transition is accompanied by the evolution of the coronal properties.",
"date": "2022-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "514",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "1422-1432",
"id_number": "CaltechAUTHORS:20220802-742430000",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220802-742430000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11773050"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11833007"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12073023"
},
{
"agency": "China Manned Space Project",
"grant_number": "CMS-CSST-2021-A06"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac1466",
"primary_object": {
"basename": "2205.12058.pdf",
"url": "https://authors.library.caltech.edu/records/n1x5b-84369/files/2205.12058.pdf"
},
"related_objects": [
{
"basename": "stac1466.pdf",
"url": "https://authors.library.caltech.edu/records/n1x5b-84369/files/stac1466.pdf"
}
],
"pub_year": "2022",
"author_list": "Dong, Yanting; Liu, Zhu; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tbb7m-wgm90",
"eprint_id": 115857,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:39:22",
"lastmod": "2025-11-20 22:12:27",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Ananna-Tonima-T",
"name": {
"family": "Ananna",
"given": "Tonima T."
},
"orcid": "0000-0001-8211-3807"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Cenko-S-Bradley",
"name": {
"family": "Cenko",
"given": "S. Bradley"
},
"orcid": "0000-0003-1673-970X"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Lamperti-Isabella",
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Lein-Amy",
"name": {
"family": "Lein",
"given": "Amy"
},
"orcid": "0000-0002-7851-9756"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Pacucci-Fabio",
"name": {
"family": "Pacucci",
"given": "Fabio"
},
"orcid": "0000-0001-9879-7780"
},
{
"id": "Pfeifle-Ryan-W",
"name": {
"family": "Pfeifle",
"given": "Ryan W."
},
"orcid": "0000-0001-8640-8522"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Salvato-Mara",
"name": {
"family": "Salvato",
"given": "Mara"
},
"orcid": "0000-0001-7116-9303"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
},
{
"id": "Shimizu-Taro",
"name": {
"family": "Shimizu",
"given": "Taro"
},
"orcid": "0000-0002-2125-4670"
},
{
"id": "Smith-Krista-L",
"name": {
"family": "Smith",
"given": "Krista L."
},
"orcid": "0000-0001-5785-7038"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
}
]
},
"title": "BASS. XXI. The Data Release 2 Overview",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; AGN host galaxies; X-ray active galactic nuclei; X-ray surveys; Sky surveys; Supermassive black holes; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. \n\nReceived 2021 September 7; revised 2022 April 29; accepted 2022 May 4; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2. \n\nWe thank the reviewer for the constructive comments that helped us improve the quality of this paper. \n\nBASS/DR2 was made possible through the coordinated efforts of a large team of astronomers, supported by various funding institutions, and using a variety of facilities. \n\nWe acknowledge support from NASA through ADAP award NNH16CT03C (M.K.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, through grant agreement No. 950533 (B.T.); FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (E.T., F.E.B); ANID grants CATA-Basal AFB-170002 (E.T., F.E.B.), ACE210002 (E.T., F.E.B.), and FB210003 (C.R., E.T., F.E.B.); ANID Anillo ACT172033 and Millennium Nucleus NCN19_058 (E.T.); Millennium Science Initiative Program\u2014ICN12_009 (F.E.B.); an ESO fellowship (M.H., J.M.); Fondecyt Iniciacion grant 11190831 (C.R.); the National Research Foundation of Korea grant NRF-2020R1C1C1005462 and the Japan Society for the Promotion of Science ID: 17321 (K.O.); Comunidad de Madrid through the Atracci\u00f3n de Talento Investigador grant 2018-T1/TIC-11035 (I.L.); support from the National Science Foundation under grant No. AST-1715512 (C.M.U.); YCAA Prize Postdoctoral Fellowship (M.B.); and from a Clay Fellowship administered by the Smithsonian Astrophysical Observatory and by the Black Hole Initiative at Harvard University, which is funded by grants from the John Templeton Foundation and the Gordon and Betty Moore Foundation (F.P.). This work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. We acknowledge the work done by the 50+ BASS scientists and Swift BAT team to make this project possible. \n\nWe acknowledge the various telescopes used in this paper. We are tremendously thankful to all the observing and support staff in all the observatories, and their headquarters, for their great assistance in planning and conducting the observations that made BASS/DR2 possible. \n\nSpecifically, BASS/DR2 is based on data obtained through the European Organisation for Astronomical Research in the Southern Hemisphere (ESO); the Palomar Observatory; the Southern Astrophysical Research (SOAR); the Kitt Peak National Observatory, managed by the US National Science Foundation's NOIRLab; the 6.5 m Magellan and the 2.5 m du Pont telescopes located at Las Campanas Observatory, Chile; the W. M. Keck Observatory at Maunakea, Hawaii; and the various stages of the Sloan Digital Sky Survey (SDSS). \n\nA full list of observing facilities, program numbers, and their supporting bodies is provided in the main DR2 Catalog paper (Koss et al. 2022a; see the acknowledgments there). \n\nA significant part of the BASS observations and work took place during the COVID-19 crisis. We thank the healthcare experts in communities around the world, for their tireless efforts to keep us all as safe and healthy as possible. \n\nFacilities: Du Pont (Boller & Chivens spectrograph) - , Keck:I (LRIS) - , Magellan:Clay - , Hale (DBSP) - , NuSTAR - , Swift (XRT and BAT) - , VLT:Kueyen (X-shooter) - , VLT:Antu (FORS2) - , SOAR (Goodman). - \n\nSoftware: Astropy (Collaboration et al. 2013), ESO Reflex (Freudling et al. 2013), IRAF (National Optical Astronomy Observatories 1999), Matplotlib (Hunter 2007), Numpy (van der Walt et al. 2011), Pandas (https://doi.org/10.5281/zenodo.3630805).\n\nPublished - Koss_2022_ApJS_261_1.pdf
Accepted Version - 2207.12428.pdf
",
"abstract": "The BAT AGN Spectroscopic Survey (BASS) is designed to provide a highly complete census of the key physical parameters of the supermassive black holes (SMBHs) that power local active galactic nuclei (AGNs) (z \u2272 0.3), including their bolometric luminosity (L_(bol)), black hole (BH) mass (M_(BH)), accretion rates (L_(bol)/L_(Edd)), line-of-sight gas obscuration (N_H), and the distinctive properties of their host galaxies (e.g., star formation rates, masses, and gas fractions). We present an overview of the second data release of BASS (DR2), an unprecedented spectroscopic AGN survey in spectral range, resolution, and sensitivity, including 1449 optical (\u223c3200 \u00c5\u20131 \u03bcm) and 233 near-IR (1\u20132.5 \u03bcm) spectra for the brightest 858 ultrahard X-ray (14\u2013195 keV) selected AGNs across the entire sky and essentially all levels of obscuration. This release provides a highly complete set of key measurements (emission-line measurements and central velocity dispersions), with 99.9% measured redshifts and 98% BH masses estimated (for unbeamed AGNs outside the Galactic plane). The BASS DR2 AGN sample represents a unique census of nearby powerful AGNs, spanning over 5 orders of magnitude in AGN bolometric luminosity (L_(bol) \u223c 10\u2074\u2070\u201310\u2074\u2077 erg s\u207b\u00b9), BH mass (M_(BH) \u223c 10\u2075\u201310\u00b9\u2070 M_\u2299), Eddington ratio (L_(bol)/L_(Edd) \u2273 10\u22125), and obscuration (N_H \u223c 10\u00b2\u2070\u201310\u00b2\u2075 cm\u207b\u00b2). The public BASS DR2 sample and measurements can thus be used to answer fundamental questions about SMBH growth and its links to host galaxy evolution and feedback in the local universe, as well as open questions concerning SMBH physics. Here we provide a brief overview of the survey strategy, the key BASS DR2 measurements, data sets and catalogs, and scientific highlights from a series of DR2-based works pursued by the BASS team.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 1",
"id_number": "CaltechAUTHORS:20220726-997598000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220726-997598000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "Comunidad de Madrid",
"grant_number": "2018-T1/TIC-11035"
},
{
"agency": "NSF",
"grant_number": "AST-1715512"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "Harvard University"
},
{
"agency": "Black Hole Initiative"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Gordon and Betty Moore Foundation"
},
{
"agency": "NSF",
"grant_number": "PHY-1607611"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac6c8f",
"primary_object": {
"basename": "2207.12428.pdf",
"url": "https://authors.library.caltech.edu/records/tbb7m-wgm90/files/2207.12428.pdf"
},
"related_objects": [
{
"basename": "Koss_2022_ApJS_261_1.pdf",
"url": "https://authors.library.caltech.edu/records/tbb7m-wgm90/files/Koss_2022_ApJS_261_1.pdf"
}
],
"pub_year": "2022",
"author_list": "Koss, Michael J.; Trakhtenbrot, Benny; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tzkks-xgn84",
"eprint_id": 115856,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:39:14",
"lastmod": "2025-11-20 20:41:17",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"name": {
"family": "Ananna",
"given": "Tonima T."
},
"orcid": "0000-0001-8211-3807"
},
{
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"name": {
"family": "B\u00e4r",
"given": "Rudolf E."
},
"orcid": "0000-0001-5481-8607"
},
{
"name": {
"family": "Becker",
"given": "George"
},
"orcid": "0000-0003-2344-263X"
},
{
"name": {
"family": "Bessiere",
"given": "Patricia"
},
"orcid": "0000-0002-0205-5940"
},
{
"name": {
"family": "Burtscher",
"given": "Leonard"
},
"orcid": "0000-0003-1014-043X"
},
{
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"name": {
"family": "Congiu",
"given": "Enrico"
},
"orcid": "0000-0002-8549-4083"
},
{
"name": {
"family": "Evans",
"given": "Phil"
},
"orcid": "0000-0002-8465-3353"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Kamraj-Nikita",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"name": {
"family": "Pacucci",
"given": "Fabio"
},
"orcid": "0000-0001-9879-7780"
},
{
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"name": {
"family": "Riffel",
"given": "Rog\u00e9rio"
},
"orcid": "0000-0002-1321-1320"
},
{
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
},
{
"name": {
"family": "Temple",
"given": "Matthew J."
},
"orcid": "0000-0001-8433-550X"
},
{
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"name": {
"family": "Veilleux",
"given": "Sylvain"
},
"orcid": "0000-0002-3158-6820"
},
{
"name": {
"family": "Williams",
"given": "Jonathan"
},
"orcid": "0000-0002-0441-3502"
}
]
},
"title": "BASS. XXII. The BASS DR2 AGN Catalog and Data",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray active galactic nuclei; Active galactic nuclei; Seyfert galaxies; X-ray quasars; X-ray surveys; Surveys; Sky surveys; Galaxy spectroscopy; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 September 3; revised 2022 April 2; accepted 2022 April 10; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2. \n\nWe thank the reviewer for the constructive comments that helped us improve the quality of this paper.\n\nBASS/DR2 was made possible through the coordinated efforts of a large team of astronomers, supported by various funding institutions, and using a variety of facilities. \n\nWe acknowledge support from NASA through ADAP award NNH16CT03C (M.K.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, through grant agreement No. 950533 (B.T.); FONDECYT Postdoctorado 3180506 (F.R.) and 3210157 (A.R.); FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (E.T., F.E.B.); ANID grants CATA-Basal AFB-170002, ACE210002, and FB210003 (C.R., F.R., E.T., F.E.B., and E.C.); ANID Anillo ACT172033 (E.T.); Millennium Science Initiative Program\u2014ICN12_009 (F.E.B.); an ESO fellowship (M.H., J.M.); and Fondecyt Iniciacion grant 11190831 (C.R.). K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462) and the Japan Society for the Promotion of Science (JSPS, ID: 17321); I.L. acknowledges support from the Comunidad de Madrid through the Atracci\u00f3n de Talento Investigador Grant 2018-T1/TIC-11035, C.M.U. acknowledges support from the National Science Foundation under grant No. AST-1715512, F.P. acknowledges support from a Clay Fellowship administered by the Smithsonian Astrophysical Observatory, and from the Black Hole Initiative at Harvard University, which is funded by grants from the John Templeton Foundation and the Gordon and Betty Moore Foundation, M.B. acknowledges support from the YCAA Prize Postdoctoral Fellowship; R.R. thanks CNPq (311223/2020-6), CAPES, and FAPERGS (16/2551-0000251-7 and 19/2551-0001750-2). This work was performed in part at Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. \n\nWe also acknowledge the following people who assisted in acquiring the Palomar observations presented herein: Dave Alexander, Roberto Assef, Rosamaria Carraro, Alison Dugas, Peter Eisenhardt, Clarke Esmerian, Carla Fuentes, Felix Fuerst, Maya Fuller, Daniel Gawerc, David Girou, Ana Glidden, Matthew Graham, Claire Greenwell, Brian Grefenstette, Marianne Heida, Hyunsung Jun, Peter Kosec, Stephanie LaMassa, Jeff Maggio, Alejandra Melo, Catalina-Ana Miritescu, Wenli Mo, Eric Mukherjee, Gael Noirot, Antonija Oklop\u010di\u0107 Sean Pike, Joseph Simon, Tawny Sit, Navin Sridhar, Aaron Stemo, Becky Tang, Thomas Venville, Jingyi Wang, and Dominika Wylezalek. We acknowledge financial contributions from Joanna Wall Muir and the California Institute of Technology's Student Faculty Program to assist in the Palomar observations for Tea Freedman-Susskind, Feiyang Liu, Milan Robertson, Yerong Xu, and Emily Zhang. We acknowledge the work that the Swift BAT team has done to make this project possible. \n\nWe acknowledge the various telescopes used in this paper. We are tremendously thankful to all the observing and support staff in all the observatories, and their headquarters, for their great assistance in planning and conducting the observations that made BASS/DR2 possible. Specifically, BASS/DR2 is based on the following: \n\n(1) Observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under 34 ESO programs: 60.A-9024(A), 60.A-9421(A), 062.H-0612(A), 086.B-0135(A), 089.B-0951(A), 089.B-0951(B), 090.A-0830(A), 090.D-0828(A), 091.B-0900(B), 091.C-0934(B), 092.B-0083(A), 093.A-0766(A), 094.B-0321(A), 095.B-0059(A), 098.A-0062, 098.A-0635(B), 098.B-0551(A), 099.A-0403(A+B), 099.A-0442(A), 099.B-0785(A), 0101.A-0765(A), 0101.B-0456(B), 0101.B-0739(A), 0102.A-0433(A), 0102.B-0048, 0103.A-0521(A), 0103.B-0566(A), 0103.A-0777(A), 0104.A-0353(A), 0104.B-0959(A), 0106.A-0521(A), 385.B-1035(A), 2100.B-5018(B), and 60.A-9100(J). \n\n(2) Data obtained with the Hale 200-inch telescope at Palomar observatory, including five dedicated Yale programs: 2017B/Y04, 2018A/Y03, 2018B/Y04, 2019A/Y03, and 2019B/Y04 (PI: M. Powell). Additional data were obtained as part of Caltech runs including 2014B/P05, 2015A/P04, 2015B/P06, 2016A/P06, 2016B/P04, 2017A/P13, 2017B/P01, 2018A/P15, 2018B/P02, 2019A/P18, 2019B/P11, 2020A/P14, and 2020B/P19 (PI: F. Harrison) and also JPL runs including 2016B/J12, 2017A/J07, 2017B/J15 2019B/J09, 2019A/J06, 2019B/J19, 2020A/J11, and 2020B/J04 (PI: D. Stern). \n\n(3) Observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00f5es (MCTI/LNA) do Brasil, the US National Science Foundation's NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). These include from CNTAC (CN2018A-104, CN2018B-83) and NOIRLab program 2012A-0463 (PI M. Trippe). \n\n(4) Observations at Kitt Peak National Observatory at NSF's NOIRLab (NOIRLab Prop. ID 52, 2946; PI: F. Bauer), which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. We are honored to be permitted to conduct astronomical research on Iolkam Du'ag (Kitt Peak), a mountain with particular significance to the Tohono O'odham. \n\n(5) Data gathered with the 6.5 m Magellan Telescopes (CN2019A-70 and CN2019B-77) and the 2.5 m du Pont telescope (CN2016A-80) located at Las Campanas Observatory, Chile. Support for the design and construction of the Magellan Echellette Spectrograph was received from the Observatories of the Carnegie Institution of Washington, the School of Science of the Massachusetts Institute of Technology, and the National Science Foundation in the form of a collaborative Major Research Instrument grant to Carnegie and MIT (AST0215989). \n\n(6) Data obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. \n\n(7) Data obtained as part of the various stages of the Sloan Digital Sky Survey (SDSS-I/II, III, and IV). Funding for the SDSS has been provided by the Alfred P. Sloan Foundation, the US Department of Energy Office of Science, and the Participating Institutions. SDSS acknowledges support and resources from the Center for High Performance Computing at the University of Utah. The SDSS website is www.sdss.org. The most recent generation of the SDSS we benefited from, SDSS-IV, is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration, including the Brazilian Participation Group, the Carnegie Institution for Science, Carnegie Mellon University, Center for Astrophysics \u2223 Harvard & Smithsonian, the Chilean Participation Group, the French Participation Group, Instituto de Astrof\u00edsica de Canarias, Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe (IPMU)/University of Tokyo, the Korean Participation Group, Lawrence Berkeley National Laboratory, Leibniz Institut f\u00fcr Astrophysik Potsdam (AIP), Max-Planck-Institut f\u00fcr Astronomie (MPIA Heidelberg), Max-Planck-Institut f\u00fcr Astrophysik (MPA Garching), Max-Planck-Institut f\u00fcr Extraterrestrische Physik (MPE), National Astronomical Observatories of China, New Mexico State University, New York University, University of Notre Dame, Observat\u00e1rio Nacional/MCTI, The Ohio State University, Pennsylvania State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, Universidad Nacional Aut\u00f3noma de M\u00e9xico, University of Arizona, University of Colorado Boulder, University of Oxford, University of Portsmouth, University of Utah, University of Virginia, University of Washington, University of Wisconsin, Vanderbilt University, and Yale University. \n\nThis research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France. \n\nA significant part of the BASS observations and work took place during the COVID-19 crisis. We thank the healthcare experts in communities around the world, for their tireless efforts to keep us all as safe and healthy as possible. \n\nFacilities: Du Pont (Boller & Chivens spectrograph), Keck:I (LRIS), Magellan:Clay, Hale (Doublespec), NuSTAR, Swift (XRT and BAT), VLT:Kueyen (X-shooter), VLT:Antu (FORS2), SOAR (Goodman). \n\nSoftware: Astropy (Collaboration et al. 2013), ESO Reflex (Freudling et al. 2013), IRAF (National Optical Astronomy Observatories 1999), Matplotlib (Hunter 2007), molecfit (Smette et al. 2015), Numpy (van der Walt et al. 2011), Pandas (https://doi.org/10.5281/zenodo.3630805), PySpecKit (Ginsburg & Mirocha 2011).\n\nPublished - Koss_2022_ApJS_261_2.pdf
Accepted Version - 2207.12432.pdf
",
"abstract": "We present the active galactic nucleus (AGN) catalog and optical spectroscopy for the second data release of the Swift BAT AGN Spectroscopic Survey (BASS DR2). With this DR2 release we provide 1449 optical spectra, of which 1182 are released for the first time, for the 858 hard-X-ray-selected AGNs in the Swift BAT 70-month sample. The majority of the spectra (801/1449, 55%) are newly obtained from Very Large Telescope (VLT)/X-shooter or Palomar/Doublespec. Many of the spectra have both higher resolution (R > 2500, N \u223c 450) and/or very wide wavelength coverage (3200\u201310000 \u00c5, N \u223c 600) that are important for a variety of AGN and host galaxy studies. We include newly revised AGN counterparts for the full sample and review important issues for population studies, with 47 AGN redshifts determined for the first time and 790 black hole mass and accretion rate estimates. This release is spectroscopically complete for all AGNs (100%, 858/858), with 99.8% having redshift measurements (857/858) and 96% completion in black hole mass estimates of unbeamed AGNs (722/752). This AGN sample represents a unique census of the brightest hard-X-ray-selected AGNs in the sky, spanning many orders of magnitude in Eddington ratio (L/L_(Edd) = 10\u22125\u2013100), black hole mass (M_(BH) = 10\u2075\u201310\u00b9\u2070 M_\u2299), and AGN bolometric luminosity (L_(bol) = 10\u2074\u2070\u201310\u2074\u2077 erg s\u207b\u00b9 ).",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 2",
"id_number": "CaltechAUTHORS:20220726-997473000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220726-997473000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3180506"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ACT172033"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "Comunidad de Madrid",
"grant_number": "2018-T1/TIC-11035"
},
{
"agency": "NSF",
"grant_number": "AST-1715512"
},
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "Black Hole Initiative"
},
{
"agency": "Harvard University"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Gordon and Betty Moore Foundation"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "311223/2020-6"
},
{
"agency": "Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "16/2551-0000251-7"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "19/2551-0001750-2"
},
{
"agency": "NSF",
"grant_number": "PHY-1607611"
},
{
"agency": "NSF",
"grant_number": "AST-0215989"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Department of Energy (DOE)"
},
{
"agency": "Participating Institutions"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac6c05",
"primary_object": {
"basename": "2207.12432.pdf",
"url": "https://authors.library.caltech.edu/records/tzkks-xgn84/files/2207.12432.pdf"
},
"related_objects": [
{
"basename": "Koss_2022_ApJS_261_2.pdf",
"url": "https://authors.library.caltech.edu/records/tzkks-xgn84/files/Koss_2022_ApJS_261_2.pdf"
}
],
"pub_year": "2022",
"author_list": "Koss, Michael J.; Ricci, Claudio; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gzepk-x4658",
"eprint_id": 115906,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:40:33",
"lastmod": "2025-11-21 00:57:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pfeifle-Ryan-W",
"name": {
"family": "Pfeifle",
"given": "Ryan W."
},
"orcid": "0000-0001-8640-8522"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Boorman-Peter-G",
"name": {
"family": "Boorman",
"given": "Peter G."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Stalevski-Marko",
"name": {
"family": "Stalevski",
"given": "Marko"
},
"orcid": "0000-0001-5146-8330"
},
{
"id": "Asmus-Daniel",
"name": {
"family": "Asmus",
"given": "Daniel"
},
"orcid": "0000-0003-0220-2063"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Satyapal-Shobita",
"name": {
"family": "Satyapal",
"given": "Shobita"
},
"orcid": "0000-0003-2277-2354"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Rosario-David-J",
"name": {
"family": "Rosario",
"given": "David J."
},
"orcid": "0000-0002-0001-3587"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith"
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "BASS. XXIII. A New Mid-infrared Diagnostic for Absorption in Active Galactic Nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Supermassive black holes; Active galactic nuclei; Black hole physics; X-ray active galactic nuclei; AGN host galaxies; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2020 August 12; revised 2021 January 25; accepted 2021 February 5; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nWe graciously thank the anonymous referee whose timely and constructive feedback aided in improving this work. We thank L. Shao and R. Boissay-Malaquin for their helpful comments on the draft. R.W.P. thanks B. L. Cale for helpful discussions regarding data fitting with Python. C.R. acknowledges support from the Fondecyt Iniciacion grant 11190831 and ANID BASAL project FB210003. P.G.B. acknowledges financial support from the STFC and Czech Science Foundation project No. 19-05599Y. D.A. acknowledges funding through the European Union's Horizon 2020 innovation program under Marie Sklodowska-Curie grant agreement No. 793499 (DUSTDEVILS). B.T. acknowledges support from the Israel Science Foundation (grant 1849/19) and from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement 950533). M.K. acknowledges support from NASA through ADAP award NNH16CT03C. F.R. acknowledges support from FONDECYT postdoctorado 3180506. E.T. acknowledges support from FONDECYT Regular 1190818 and 1200495, ANID grants CATA-Basal AFB-170002, ACE210002, and FB210003, and Millennium Nucleus NCN19_058. This work is partially supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (18K13584 and 20H01939; K.I.). K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). M.S. acknowledges support by the Ministry of Education, Science and Technological Development of the Republic of Serbia through contract No. 451-03-68/2020/14/20002 and the Science Fund of the Republic of Serbia, PROMIS 6060916, BOWIE. \n\nFacilities: Chandra, GALEX, NuSTAR, SDSS, Suzaku, Swift, WISE, XMM-Newton. \n\nSoftware: odr (Boggs & Rogers et al. 1990; Virtanen et al. 2020), pandas (McKinney 2010), scipy (Virtanen et al. 2020), numpy (Oliphant 2006; van der Walt et al. 2011; Oliphant 2015), matplotlib (Hunter 2007), BXA (Buchner et al. 2014).\n\nThis publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III website is http://www.sdss3.org/.\n\nThis research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.\n\nPublished - Pfeifle_2022_ApJS_261_3.pdf
Accepted Version - 2102.04412.pdf
",
"abstract": "In this study, we use the Swift/BAT AGN sample, which has received extensive multiwavelength follow-up analysis as a result of the BAT AGN Spectroscopic Survey, to develop a diagnostic for nuclear obscuration by examining the relationship between the line-of-sight column densities (N_H), the 2\u201310 keV to 12 \u03bcm luminosity ratio, and WISE mid-infrared colors. We demonstrate that heavily obscured AGNs tend to exhibit both preferentially \"redder\" mid-infrared colors and lower values of L_(X,Obs.)/L_(12 \u03bcm) than less obscured AGNs, and we derive expressions relating N_H to the L_(X,Obs.)/L_(12 \u03bcm) and L_(22 \u03bcm)/L_(4.6 \u03bcm) luminosity ratios, as well as develop diagnostic criteria using these ratios. Our diagnostic regions yield samples that are \u2273 80% complete and \u2273 60% pure for AGNs with log(N_H/cm\u207b\u00b2) \u2265 24, as well as \u2273 85% pure for AGNs with log(N_H/cm\u207b\u00b2) \u2273 23.5. We find that these diagnostics cannot be used to differentiate between optically star-forming galaxies and active galaxies. Further, mid-IR contributions from host galaxies that dominate the observed 12 \u03bcm emission can lead to larger apparent X-ray deficits and redder mid-IR colors than the AGNs would intrinsically exhibit, though this effect helps to better separate less and more obscured AGNs. Finally, we test our diagnostics on two catalogs of AGNs and infrared galaxies, including the XMM-Newton XXL-N field, and we identify several known Compton-thick AGNs, as well as a handful of candidate heavily obscured AGNs based upon our proposed obscuration diagnostics.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 3",
"id_number": "CaltechAUTHORS:20220727-37302000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-37302000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Czech Science Foundation",
"grant_number": "19-05599Y"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "793499"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3180506"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18K13584"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "20H01939"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Ministry of Education, Science and Technological Development (Serbia)",
"grant_number": "451-03-68/2020/14/20002"
},
{
"agency": "Science Fund (Serbia)",
"grant_number": "6060916"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Participating Institutions"
},
{
"agency": "NSF"
},
{
"agency": "Department of Energy (DOE)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac5b65",
"primary_object": {
"basename": "2102.04412.pdf",
"url": "https://authors.library.caltech.edu/records/gzepk-x4658/files/2102.04412.pdf"
},
"related_objects": [
{
"basename": "Pfeifle_2022_ApJS_261_3.pdf",
"url": "https://authors.library.caltech.edu/records/gzepk-x4658/files/Pfeifle_2022_ApJS_261_3.pdf"
}
],
"pub_year": "2022",
"author_list": "Pfeifle, Ryan W.; Ricci, Claudio; et al."
},
{
"id": "https://authors.library.caltech.edu/records/cgtkk-xe207",
"eprint_id": 115903,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:40:11",
"lastmod": "2025-11-21 02:15:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Ueda-Yoshihiro",
"name": {
"family": "Ueda",
"given": "Yoshihiro"
},
"orcid": "0000-0001-7821-6715"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Lamperti-Isabella",
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "Rudolf E."
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "Rojas-Alejandra-F",
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Riffel-Rog\u00e9rio",
"name": {
"family": "Riffel",
"given": "Rog\u00e9rio"
},
"orcid": "0000-0002-1321-1320"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
}
]
},
"title": "BASS. XXIV. The BASS DR2 Spectroscopic Line Measurements and AGN Demographics",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Supermassive black holes; Active galactic nuclei; X-ray active galactic nuclei; AGN host galaxies; Quasars; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 December 16; revised 2022 February 16; accepted 2022 February 17; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nWe are grateful to the anonymous referee for a number of clarifications that improved the quality of the manuscript. K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). This research was supported in part by the Japan Society for the Promotion of Science (JSPS) postdoctoral fellowship program for research in Japan (ID: P17321). We acknowledge support from NASA through ADAP award NNH16CT03C (M.K.); the JSPS KAKENHI grant No. 20H01946 (Y.U.); the Fondecyt Iniciacion grant 11190831 (C.R.); the Israel Science Foundation (grant No. 1849/19, B.T.); the Comunidad de Madrid through the Atracci\u00f3n de Talento Investigador Grant 2018-T1/TIC-11035 (I.L.); FONDECYT Postdoctorado project No. 3210157 (A.R.L.). R.R. thanks to Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq, Proj. 311223/2020-6, 304927/2017-1 and 400352/2016-8), Funda\u00e7\u00e3o de amparo \u00e0 pesquisa do Rio Grande do Sul (FAPERGS, Proj. 16/2551-0000251-7 and 19/1750-2), Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES, Proj. 0001). We acknowledge support from FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (F.E.B., E.T.), ANID grants CATA-Basal AFB-170002 and FB210003 (E.T., F.E.B.), Anillo ACT172033 (E.T.), Millennium Nucleus NCN19_058 (TITANs; E.T.) and Millennium Science Initiative Program 2013 ICN12_009 (MAS; F.E.B.). C.M.U. acknowledges support from the National Science Foundation under grant No. AST-1715512. \n\nSome of the optical spectra were taken with Doublespec at Palomar via Yale (PI M. Powell, 2017-2019, 16 nights) as well as Caltech (PI F. Harrison) and JPL (PI D. Stern) from programs from 2013\u20132020. \n\nThis work made use of observations collected at the European Southern Observatory under ESO programs 98.A-0635, 99-A-0403, 100.B-0672, 101.A-0765, 102.A-0433, 103.A-0521, and 104.A-0353. Based on observations from seven CNTAC programs: CN2016A-80, CN2018A-104, CN2018B-83, CN2019A-70, CN2019B-77, CN2020A-90, and CN2020B-48 (PI C. Ricci). Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00f5es (MCTI/LNA) do Brasil, the US National Science Foundations NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). Based on observations at Kitt Peak National Observatory at NSFs NOIRLab (NOIRLab Prop. ID 52, 2946; PI: F. Bauer), which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. \n\nThis research has made use of NASA's ADS Service. This research has made use of the NASA/ IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. \n\nFunding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III website is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. \n\nThe Digitized Sky Surveys were produced at the Space Telescope Science Institute under U.S. Government grant NAG W-2166. The images of these surveys are based on photographic data obtained using the Oschin Schmidt Telescope on Palomar Mountain and the UK Schmidt Telescope. The plates were processed into the present compressed digital form with the permission of these institutions. The National Geographic Society\u2014Palomar Observatory Sky Atlas (POSS-I) was made by the California Institute of Technology with grants from the National Geographic Society. The Second Palomar Observatory Sky Survey (POSS-II) was made by the California Institute of Technology with funds from the National Science Foundation, the National Geographic Society, the Sloan Foundation, the Samuel Oschin Foundation, and the Eastman Kodak Corporation. The Oschin Schmidt Telescope is operated by the California Institute of Technology and Palomar Observatory. The UK Schmidt Telescope was operated by the Royal Observatory Edinburgh, with funding from the UK Science and Engineering Research Council (later the UK Particle Physics and Astronomy Research Council), until 1988 June, and thereafter by the Anglo-Australian Observatory. The blue plates of the southern Sky Atlas and its Equatorial Extension (together known as the SERC-J), as well as the Equatorial Red (ER), and the Second Epoch [red] Survey (SES) were all taken with the UK Schmidt. \n\nFacilities: Du Pont (Boller and Chivens spectrograph) - , Hale (Doublespec) - , Keck:I (LRIS) - , SOAR (Goodman) - , Swift(BAT) - , VLT:Kueyen (X-Shooter) - . \n\nSoftware: gandalf (Sarzi et al. 2006), ESO Reflex (Freudling et al. 2013).\n\nPublished - Oh_2022_ApJS_261_4.pdf
Accepted Version - 2203.00017.pdf
",
"abstract": "We present the second catalog and data release of optical spectral line measurements and active galactic nucleus (AGN) demographics of the BAT AGN Spectroscopic Survey, which focuses on the Swift-BAT hard X-ray detected AGNs. We use spectra from dedicated campaigns and publicly available archives to investigate spectral properties of most of the AGNs listed in the 70 month Swift-BAT all-sky catalog; specifically, 743 of the 746 unbeamed and unlensed AGNs (99.6%). We find a good correspondence between the optical emission line widths and the hydrogen column density distributions using the X-ray spectra, with a clear dichotomy of AGN types for N_H = 10\u00b2\u00b2 cm\u207b\u00b2. Based on optical emission-line diagnostics, we show that 48%\u201375% of BAT AGNs are classified as Seyfert, depending on the choice of emission lines used in the diagnostics. The fraction of objects with upper limits on line emission varies from 6% to 20%. Roughly 4% of the BAT AGNs have lines too weak to be placed on the most commonly used diagnostic diagram, [O iii]\u03bb5007/H\u03b2 versus [N ii]\u03bb6584/H\u03b1, despite the high signal-to-noise ratio of their spectra. This value increases to 35% in the [O iii]\u03bb5007/[O ii]\u03bb3727 diagram, owing to difficulties in line detection. Compared to optically selected narrow-line AGNs in the Sloan Digital Sky Survey, the BAT narrow-line AGNs have a higher rate of reddening/extinction, with H\u03b1/H\u03b2 > 5 (\u223c36%), indicating that hard X-ray selection more effectively detects obscured AGNs from the underlying AGN population. Finally, we present a subpopulation of AGNs that feature complex broad lines (34%, 250/743) or double-peaked narrow emission lines (2%, 17/743).",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 4",
"id_number": "CaltechAUTHORS:20220727-36831000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-36831000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Research Foundation of Korea",
"grant_number": "2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "P17321"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "20H01946"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "Comunidad de Madrid",
"grant_number": "2018-T1/TIC-11035"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "311223/2020-6"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "304927/2017-1"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "400352/2016-8"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "16/2551-0000251-7"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "19/1750-2"
},
{
"agency": "Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)",
"grant_number": "0001"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "NSF",
"grant_number": "AST-1715512"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Department of Energy (DOE)"
},
{
"agency": "Participating Institutions"
},
{
"agency": "NASA",
"grant_number": "NAG W-2166"
},
{
"agency": "National Geographic Society"
},
{
"agency": "Samuel Oschin Foundation"
},
{
"agency": "Eastman Kodak Corporation"
},
{
"agency": "Science and Engineering Research Council (SERC)"
},
{
"agency": "Particle Physics and Astronomy Research Council (PPARC)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac5b68",
"primary_object": {
"basename": "2203.00017.pdf",
"url": "https://authors.library.caltech.edu/records/cgtkk-xe207/files/2203.00017.pdf"
},
"related_objects": [
{
"basename": "Oh_2022_ApJS_261_4.pdf",
"url": "https://authors.library.caltech.edu/records/cgtkk-xe207/files/Oh_2022_ApJS_261_4.pdf"
}
],
"pub_year": "2022",
"author_list": "Oh, Kyuseok; Koss, Michael J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vq3j6-a1603",
"eprint_id": 115904,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:40:19",
"lastmod": "2025-11-20 20:30:45",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "Rudolf"
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "Bessiere-Patricia",
"name": {
"family": "Bessiere",
"given": "Patricia"
},
"orcid": "0000-0002-0205-5940"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Kakkad-Darshan",
"name": {
"family": "Kakkad",
"given": "Darshan"
},
"orcid": "0000-0002-2603-2639"
},
{
"id": "Lamperti-Isabella",
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Riffell-Roger\u00edo",
"name": {
"family": "Riffel",
"given": "Rogerio"
},
"orcid": "0000-0002-1321-1320"
},
{
"id": "Rojas-Alejandra-F",
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Sani-Eleonora",
"name": {
"family": "Sani",
"given": "Eleonora"
},
"orcid": "0000-0002-3140-4070"
},
{
"id": "Smith-Krista-L",
"name": {
"family": "Smith",
"given": "Krista L."
},
"orcid": "0000-0001-5785-7038"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Veilleux-Sylvain",
"name": {
"family": "Veilleux",
"given": "Sylvain"
},
"orcid": "0000-0002-3158-6820"
}
]
},
"title": "BASS. XXIX. The Near-infrared View of the Broad-line Region (BLR): The Effects of Obscuration in BLR Characterization",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; High energy astrophysics; X-ray active galactic nuclei; Active galaxies; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2020 December 13; revised 2021 August 28; accepted 2021 August 30; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nThis paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.\n\nWe thank the anonymous referee for the useful comments that improved our manuscript. F.R. thanks the LCO Instrument & Operations Support Specialists that supported our runs at LCO using Magellan/FIRE, and in particular G. Prieto for sharing the record of local weather data used to run the molecfit correction on our FIRE observations. We acknowledge support from FONDECYT Postdoctorado 3180506 (F.R.) and 3210157 (A.R.L.); from PRIN MIUR 2017 project \"black hole winds and the Baryon Life Cycle of Galaxies: the stone-guest at the galaxy evolution supper,\" contract #2017PH3WAT (F.R.); FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (F.E.B., E.T.); ANID grants CATA-Basal AFB-170002 (F.R., E.T., F.E.B.) and ANID BASAL CATA ACE210002 and FB210003 (E.T., F.E.B., C.R.); ANID Anillo ACT172033 (E.T.); from Millennium Nucleus NCN19_058 TITANs (E.T.); and Chile's Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC12_009, awarded to The Millennium Institute of Astrophysics, MAS (F.E.B.); from NASA through ADAP award NNH16CT03C (M.K.); the ANID+PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080 and Fondecyt Iniciacion grant 11190831 (C.R.); from the State Research Agency (AEI-MCINN) and from the Spanish MCIU under grant \"Feeding and feedback in active galaxies\" with reference PID2019-106027GB-C42 (P.S.B.); from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, grant agreement 950533, and the Israel Science Foundation, grant No. 1849/19 (B.T.); the National Research Foundation of Korea (NRF-2020R1C1C1005462, K.O.); the Japan Society for the Promotion of Science (JSPS, ID: 17321, K.O.); the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. C.M.U. acknowledges support from the National Science Foundation under grant No. AST-1715512. We acknowledge support from the Comunidad de Madrid through the Atracci\u00f3n de Talento Investigador grant 2018-T1/TIC-11035 (I.L.). \n\nFacilities: Magellan-LCO - , Swift (BAT). - \n\nSoftware: FireHose (v2; Gagn\u00e9 et al. 2015), molecfit (Smette et al. 2015), pymccorrelation package (Privon et al. 2020), PySpecKit (v0.1.21; Ginsburg & Mirocha 2011).\n\nPublished - Ricci_2022_ApJS_261_8.pdf
Accepted Version - 2111.13720.pdf
",
"abstract": "Virial black hole (BH) mass (MBH) determination directly involves knowing the broad-line region (BLR) clouds' velocity distribution, their distance from the central supermassive BH (R_(BLR)), and the virial factor (f). Understanding whether biases arise in M_(BH) estimation with increasing obscuration is possible only by studying a large (N > 100) statistical sample of obscuration-unbiased (hard) X-ray-selected active galactic nuclei (AGNs) in the rest-frame near-infrared (0.8\u20132.5 \u03bcm) since it penetrates deeper into the BLR than the optical. We present a detailed analysis of 65 local Burst Alert Telescope (BAT) selected Seyfert galaxies observed with Magellan/FIRE. Adding these to the near-infrared BAT AGN spectroscopic survey database, we study a total of 314 unique near-infrared spectra. While the FWHMs of H\u03b1 and near-infrared broad lines (He i, Pa\u03b2, Pa\u03b1) remain unbiased to either BLR extinction or X-ray obscuration, the H\u03b1 broad-line luminosity is suppressed when N_H \u2273 10\u00b2\u00b9 cm\u207b\u00b2, systematically underestimating M_(BH) by 0.23\u20130.46 dex. Near-infrared line luminosities should be preferred to H\u03b1 until N_H < 10\u00b2\u00b2 cm\u207b\u00b2, while at higher obscuration a less-biased R_(BLR) proxy should be adopted. We estimate f for Seyfert 1 and 2 using two obscuration-unbiased M_(BH) measurements, i.e., the stellar velocity dispersion and a BH mass prescription based on near-infrared and X-ray, and find that the virial factors do not depend on the redshift or obscuration, but some broad lines show a mild anticorrelation with M_(BH). Our results show the critical impact obscuration can have on BLR characterization and the importance of the near-infrared and X-rays for a less-biased view of the BLR.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 8",
"id_number": "CaltechAUTHORS:20220727-36915000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-36915000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3180506"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca (MIUR)",
"grant_number": "2017PH3WAT"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Ministry of Economy, Development, and Tourism (Chile)",
"grant_number": "IC12_009"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PAI77170080"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Ministerio de Ciencia, Innovaci\u00f3n y Universidades (MCIU)",
"grant_number": "PID2019-106027GB-C42"
},
{
"agency": "Agencia Estatal de Investigaci\u00f3n"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NSF",
"grant_number": "AST-1715512"
},
{
"agency": "Comunidad de Madrid",
"grant_number": "2018-T1/TIC-11035"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac5b67",
"primary_object": {
"basename": "2111.13720.pdf",
"url": "https://authors.library.caltech.edu/records/vq3j6-a1603/files/2111.13720.pdf"
},
"related_objects": [
{
"basename": "Ricci_2022_ApJS_261_8.pdf",
"url": "https://authors.library.caltech.edu/records/vq3j6-a1603/files/Ricci_2022_ApJS_261_8.pdf"
}
],
"pub_year": "2022",
"author_list": "Ricci, Federica; Treister, Ezequiel; et al."
},
{
"id": "https://authors.library.caltech.edu/records/hzj83-4vw18",
"eprint_id": 115901,
"eprint_status": "archive",
"datestamp": "2023-10-09 21:06:45",
"lastmod": "2025-11-20 23:41:21",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. M."
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Ananna-Tonima-Tasnim",
"name": {
"family": "Ananna",
"given": "Tonima Tasnim"
},
"orcid": "0000-0001-8211-3807"
},
{
"id": "Asmus-Daniel",
"name": {
"family": "Asmus",
"given": "Daniel"
},
"orcid": "0000-0003-0220-2063"
},
{
"id": "Assef-Roberto-J",
"name": {
"family": "Assef",
"given": "Roberto J."
},
"orcid": "0000-0002-9508-3667"
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "Rudolf E."
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "Bessiere-Patricia-S",
"name": {
"family": "Bessiere",
"given": "Patricia S."
},
"orcid": "0000-0002-0205-5940"
},
{
"id": "Burtscher-Leonard",
"name": {
"family": "Burtscher",
"given": "Leonard"
},
"orcid": "0000-0003-1014-043X"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Kakkad-Darshan",
"name": {
"family": "Kakkad",
"given": "Darshan"
},
"orcid": "0000-0002-2603-2639"
},
{
"id": "Kamraj-Nikita",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "Rojas-Alejandra-F",
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Sani-Eleonora",
"name": {
"family": "Sani",
"given": "Eleonora"
},
"orcid": "0000-0002-3140-4070"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
},
{
"id": "Veilleux-Sylvain",
"name": {
"family": "Veilleux",
"given": "Sylvain"
},
"orcid": "0000-0002-3158-6820"
}
]
},
"title": "BASS. XXV. DR2 Broad-line-based Black Hole Mass Estimates and Biases from Obscuration",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; Surveys; Catalogs; Supermassive black holes; X-ray surveys; M-sigma relation; Seyfert galaxies; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 March 31; revised 2022 March 11; accepted 2022 March 14; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nWe thank the anonymous referee for their constructive comments, which helped us improve the paper. We also thank Lea Marcotulli for her assistance with identifying beamed AGN candidates, and Jonathan Stern for his insightful comments. \n\nB.T. acknowledges support from the Israel Science Foundation (grant No. 1849/19) and from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 950533). M.K. acknowledges support from NASA through ADAP award NNH16CT03C. K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). C.R. acknowledges support from the Fondecyt Iniciacion grant 11190831. We also acknowledge support from ANID grants CATA-Basal AFB-170002 (F.R., F.E.B., E.T.) and FB210003 (C.R., F.E.B., E.T., R.J.A.); FONDECYT Regular 1190818 (E.T., F.E.B.), 1191124 (R.J.A.), and 1200495 (F.E.B., E.T.); FONDECYT Postdoctorado 3180506 (F.R.) and 3210157 (A.R.); Anillo ACT172033 (E.T.); and Millennium Science Initiative ICN12_009 (MAS; F.E.B.) and Millennium Nucleus NCN19_058 (TITANs; E.T.). D.A. acknowledges funding through the European Union's Horizon 2020 and Innovation program under the Marie Sklodowska-Curie grant agreement No. 793499 (DUSTDEVILS). The work of K.I. is supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (18K13584, 20H01939). \n\nThis work relies on data collected with a large variety of facilities and analyzed using several tools. We acknowledge the work that the Swift BAT team has done to make this project possible, and the teams of the various observatories that obtained the data used in this paper. Specifically, this work is based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under 29 ESO programmes: 60.A-9024(A), 60.A-9421(A), 062.H-0612(A), 086.B-0135(A), 089.B-0951(A), 089.B-0951(B), 090.A-0830(A), 090.D-0828(A), 091.B-0900(B), 091.C-0934(B), 092.B-0083(A), 093.A-0766(A), 095.B-0059(A), 098.A-0062, 098.A-0635(B), 099.A-0403(A), 099.A-0403(B), 099.A-0442(A), 099.B-0785(A), 0101.A-0765(A), 0101.B-0456(B), 0101.B-0739(A), 0102.A-0433(A), 0103.A-0521(A), 0103.B-0566(A), 0104.A-0353(A), 0104.B-0959(A), 0106.A-0521(A), 385.B-1035(A), and 2100.B-5018(B). \n\nBASS/DR2 also relies on observations from seven CNTAC programs: CN2016A-80, CN2018A-104, CN2018B-83, CN2019A-70, CN2019B-77, CN2020A-90, and CN2020B-48 (PI C. Ricci); and from NOIRLab program 2012A-0463 (PI M. Trippe). Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the US Department of Energy Office of Science. The SDSS-III website is http://www.sdss3.org/. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. \n\nThis research made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration and the SIMBAD database, operated at CDS, Strasbourg, France (Wenger et al. 2000). \n\nFacilities: Keck:I (LRIS) - , Magellan:Clay - , Palomar:Hale(Doublespec) - , NuSTAR - , Swift (XRT and BAT) - , VLT:Kueyen (X-Shooter) - , VLT:Antu (FORS2) - , SOAR (Goodman) - . \n\nSoftware: AstroPy (Astropy Collaboration et al. 2013, 2018), Matplotlib (Hunter 2007), NumPy (Harris et al. 2020).\n\nPublished - Mejia-Restrepo_2022_ApJS_261_5.pdf
Submitted - 2204-05321.pdf
",
"abstract": "We present measurements of broad emission lines and virial estimates of supermassive black hole masses (M_(BH)) for a large sample of ultra-hard X-ray selected active galactic nuclei (AGNs) as part of the second data release of the BAT AGN Spectroscopic Survey (BASS/DR2). Our catalog includes M_(BH) estimates for a total 689 AGNs, determined from the H\u03b1, H\u03b2, MgII\u03bb2798, and/or CIV\u03bb1549 broad emission lines. The core sample includes a total of 512 AGNs drawn from the 70-month Swift/BAT all-sky catalog. We also provide measurements for 177 additional AGNs that are drawn from deeper Swift/BAT survey data. We study the links between MBH estimates and line-of-sight obscuration measured from X-ray spectral analysis. We find that broad H\u03b1 emission lines in obscured AGNs (log(N_H/cm\u207b\u00b2) > 22.0) are on average a factor of 8.0^(+4.1)_(\u22122.4) weaker, relative to ultra-hard X-ray emission, and about 35\u207a\u2077\u208b\u2081\u2082% narrower than in unobscured sources (i.e., log(N_H/cm\u207b\u00b2) < 21.5). This indicates that the innermost part of the broad-line region is preferentially absorbed. Consequently, current single-epoch M_(BH) prescriptions result in severely underestimated (> 1 dex) masses for Type 1.9 sources (AGNs with broad H\u03b1 but no broad H\u03b2) and/or sources with log(N_H/cm\u207b\u00b2) \u2273 22.0. We provide simple multiplicative corrections for the observed luminosity and width of the broad H\u03b1 component (L[bH\u03b1] and FWHM[bH\u03b1]) in such sources to account for this effect, and to (partially) remedy MBH estimates for Type 1.9 objects. As key ingredient of BASS/DR2, our work provides the community with the data needed to further study powerful AGNs in the low-redshift Universe.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 5",
"id_number": "CaltechAUTHORS:20220727-36019000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-36019000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1191124"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3180506"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ACT172033"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "793499"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18K13584"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "20H01939"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Department of Energy (DOE)"
},
{
"agency": "Participating Institutions"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac6602",
"primary_object": {
"basename": "2204-05321.pdf",
"url": "https://authors.library.caltech.edu/records/hzj83-4vw18/files/2204-05321.pdf"
},
"related_objects": [
{
"basename": "Mejia-Restrepo_2022_ApJS_261_5.pdf",
"url": "https://authors.library.caltech.edu/records/hzj83-4vw18/files/Mejia-Restrepo_2022_ApJS_261_5.pdf"
}
],
"pub_year": "2022",
"author_list": "Mej\u00eda-Restrepo, Julian E.; Trakhtenbrot, Benny; et al."
},
{
"id": "https://authors.library.caltech.edu/records/y6fef-qyh14",
"eprint_id": 115902,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:40:04",
"lastmod": "2025-11-20 23:07:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Lamperti-Isabella",
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "Rudolf E."
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "Riffel-Rog\u00e9rio",
"name": {
"family": "Riffel",
"given": "Rog\u00e9rio"
},
"orcid": "0000-0002-1321-1320"
},
{
"id": "Rojas-Alejandra-F",
"name": {
"family": "Rojas",
"given": "Alejandra F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "BASS. XXVI. DR2 Host Galaxy Stellar Velocity Dispersions",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Supermassive black holes; X-ray surveys; Sky surveys; X-ray active galactic nuclei; AGN host galaxies; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 January 12; revised 2022 February 11; accepted 2022 February 16; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nWe thank Vivian Baldassare and Amy Reines for their assistance with dwarf AGN masses. We acknowledge support from NASA through ADAP award NNH16CT03C (M.K.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program through grant agreement No. 950533 (B.T.); FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (E.T., F.E.B); FONDECYT Postdoctoral Fellowship 3210157 (A.R.); ANID grants CATA-Basal AFB-170002 (E.T., F.E.B.), ACE210002 (E.T., F.E.B.), and FB210003 (C.R., E.T., F.E.B.); ANID Anillo ACT172033 and Millennium Nucleus NCN19_058 (E.T.); Millennium Science Initiative Program ICN12_009 (F.E.B.); an ESO fellowship (M.H., J.M.); Fondecyt Iniciacion grant 11190831 (C.R.); the National Research Foundation of Korea grant NRF-2020R1C1C1005462 and the Japan Society for the Promotion of Science ID 17321 (K.O.); Comunidad de Madrid through the Atracci\u00f3n de Talento Investigador Grant 2018-T1/TIC-11035 (I.L.); YCAA Prize Postdoctoral Fellowship (M.B.); Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq; Proj. 311223/2020-6, 304927/2017-1, and 400352/2016-8); Funda\u00e7\u00e3o de amparo \u00e0 pesquisa do Rio Grande do Sul (FAPERGS; Proj. 16/2551-0000251-7 and 19/1750-2); and Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES; Proj. 0001; R.R.). This work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. We acknowledge the work done by the Swift/BAT team and the 50+ BASS scientists to make this project possible. \n\nSome of the optical spectra were taken with DoubleSpec at Palomar via Yale (PI: M. Powell; 2017-2019, 16 nights), as well as Caltech (PI: F. Harrison) and JPL (PI: D. Stern) from programs from 2013\u20132021. \n\nThis work made use of observations collected at the European Southern Observatory under ESO programs 0101.A-0765(A), 0101.B-0456(B), 0102.A-0433(A), 0102.B-0048, 0103.A-0521(A), 0103.A-0777(A), 0104.A-0353(A), 090.A-0830(A), 092.B-0083(A), 093.A-0766(A), 095.B-0059(A), 098.A-0635(B), 099.A-0403(A), 099.A-0403(B), 094.B-0321(A), 098.B-0551(A), 60.A-9421(A), and 60.A-9100(J). Based on observations from six CNTAC programs: CN2018A-104, CN2018B-83, CN2019A-70, CN2019B-77, CN2020A-90, and CN2020B-48 (PI: C. Ricci). Based on NOIRLab proposals (2012A-0463; PI: M. Trippe). Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00f5es (MCTI/LNA) do Brasil, the US National Science Foundation's NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). \n\nSome of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. \n\nThis research has made use of NASA's ADS Service. This research has made use of the NASA/IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. \n\nFunding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III website is http://www.sdss3.org/. The SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration, including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, the University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, the Max Planck Institute for Astrophysics, the Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, the University of Portsmouth, Princeton University, the Spanish Participation Group, the University of Tokyo, the University of Utah, Vanderbilt University, the University of Virginia, the University of Washington, and Yale University. \n\nFacilities: IRSA - , Keck:I (LRIS) - , Magellan:Clay - , Hale (Doublespec) - , Swift (BAT) - , VLT:Kueyen (X-Shooter) - , VLT:Antu (FORS2) - , SOAR (Goodman) - \n\nSoftware: astropy (Astropy Collaboration et al. 2013), Matplotlib (Hunter 2007), Numpy (van der Walt et al. 2011).\n\nPublished - Koss_2022_ApJS_261_6.pdf
Accepted Version - 2207.12435.pdf
",
"abstract": "We present new central stellar velocity dispersions for 484 Sy 1.9 and Sy 2 from the second data release of the Swift/BAT AGN Spectroscopic Survey (BASS DR2). This constitutes the largest study of velocity dispersion measurements in X-ray-selected obscured active galactic nuclei (AGN) with 956 independent measurements of the Ca ii H and K \u03bb3969, 3934 and Mg I \u03bb5175 region (3880\u20135550 \u00c5) and the calcium triplet region (8350\u20138730 \u00c5) from 642 spectra mainly from VLT/X-Shooter or Palomar/DoubleSpec. Our sample spans velocity dispersions of 40\u2013360 km s1, corresponding to 4\u20135 orders of magnitude in black hole mass (M_(BH) = 10^(5.5\u22129.6) M_\u2299), bolometric luminosity (L_(bol) \u223c 10\u2074\u00b2\u207b\u2074\u2076 erg s\u207b\u00b9), and Eddington ratio (L/L_(Edd) \u223c 10\u207b\u2075 to 2). For 281 AGN, our data and analysis provide the first published central velocity dispersions, including six AGN with low-mass black holes (M_(BH) = 10^(5.5\u22126.5) M_\u2299), discovered thanks to high spectral resolution observations (\u03c3_(inst) \u223c 25 km s\u207b\u00b9). The survey represents a significant advance with a nearly complete census of velocity dispersions of hard X-ray\u2013selected obscured AGN with measurements for 99% of nearby AGN (z b\u2223 > 10\u00b0). The BASS AGN have much higher velocity dispersions than the more numerous optically selected narrow-line AGN (i.e., \u223c150 versus \u223c100 km s\u207b\u00b9) but are not biased toward the highest velocity dispersions of massive ellipticals (i.e., >250 km s\u207b\u00b9). Despite sufficient spectral resolution to resolve the velocity dispersions associated with the bulges of small black holes (\u223c10\u2074\u207b\u2075 M_\u2299), we do not find a significant population of super-Eddington AGN. Using estimates of the black hole sphere of influence from velocity dispersion, direct stellar and gas black hole mass measurements could be obtained with existing facilities for more than \u223c100 BASS AGN.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 6",
"id_number": "CaltechAUTHORS:20220727-36815000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-36815000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACE210002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "Comunidad de Madrid",
"grant_number": "2018-T1/TIC-11035"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "311223/2020-6"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "304927/2017-1"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "400352/2016-8"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "16/2551-0000251-7"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "19/1750-2"
},
{
"agency": "Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)",
"grant_number": "0001"
},
{
"agency": "NSF",
"grant_number": "PHY-1607611"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Department of Energy (DOE)"
},
{
"agency": "Participating Institutions"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac650b",
"primary_object": {
"basename": "2207.12435.pdf",
"url": "https://authors.library.caltech.edu/records/y6fef-qyh14/files/2207.12435.pdf"
},
"related_objects": [
{
"basename": "Koss_2022_ApJS_261_6.pdf",
"url": "https://authors.library.caltech.edu/records/y6fef-qyh14/files/Koss_2022_ApJS_261_6.pdf"
}
],
"pub_year": "2022",
"author_list": "Koss, Michael J.; Trakhtenbrot, Benny; et al."
},
{
"id": "https://authors.library.caltech.edu/records/k8k4m-pga96",
"eprint_id": 115905,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:40:26",
"lastmod": "2025-11-20 20:39:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob S."
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Cantalupo-Sebastiano",
"name": {
"family": "Cantalupo",
"given": "Sebastiano"
},
"orcid": "0000-0001-5804-1428"
},
{
"id": "Lamperti-Isabella",
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Riffel-Rogerio",
"name": {
"family": "Riffel",
"given": "Rogerio"
},
"orcid": "0000-0002-1321-1320"
},
{
"id": "Rodr\u00edguez-Ardila-Alberto",
"name": {
"family": "Rodr\u00edguez-Ardila",
"given": "Alberto"
},
"orcid": "0000-0002-7608-6109"
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "Rudolf"
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Boissay-Malaquin-Rozenn",
"name": {
"family": "Boissay-Malaquin",
"given": "Rozenn"
},
"orcid": "0000-0003-2704-599X"
},
{
"id": "Stalevski-Marko",
"name": {
"family": "Stalevski",
"given": "Marko"
},
"orcid": "0000-0001-5146-8330"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Veilleux-Sylvain",
"name": {
"family": "Veilleux",
"given": "Sylvain"
},
"orcid": "0000-0002-3158-6820"
}
]
},
"title": "BASS. XXVIII. Near-infrared Data Release 2: High-ionization and Broad Lines in Active Galactic Nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2020 August 11; revised 2021 December 16; accepted 2021 December 28; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nBased on observations collected under programs 086.B-0135(A), 089.B-0951(A), 090.A-0830(A), 091.B-0900(B), 093.A-0766(A), 098.A-0635(B), 099.A-0403(B), 0101.A-0765(A), and 0102.A-0433(A) with X-shooter at the Very Large Telescope of the Paranal Observatory in Chile, operated by the European Southern Observatory.\n\nWe acknowledge support from NASA through ADAP award NNH16CT03C and 80NSSC19K0749 (M.J.K.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme through grant agreement No. 726384/Empire (J.S.d.B.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, through grant agreement No. 950533 (B.T.); the Comunidad de Madrid through the Atracci\u00f3n de Talento Investigador Grant 2018-T1/TIC-11035 (I.L.); National Research Foundation of Korea award NRF-2020R1C1C1005462 (K.O.); the Japan Society for the Promotion of Science, ID: 17321 (K.O.); the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA (D.S.); Swiss National Science Foundation grants PP00P2_163824 and PP00P2_190092 (S.C.); the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme grant agreement No. 864361 (S.C.); ANID grants CATA-Basal AFB-170002 (F.E.B., F.R., E.T.) and ANID BASAL project FB210003 (F.E.B., C.R., E.T.), FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (F.E.B., E.T.), Fondecyt Iniciacion grant 11190831 (C.R.), FONDECYT Postdoctorado 3180506 (F.R.), and Millennium Science Initiative ICN12_009 (F.E.B.); Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq), CAPES, and FAPERGS (R.R.); CNPq, through grant 312036/2019-1 (A.R.-A.); and the Ministry of Education, Science and Technological Development of the Republic of Serbia through contract No. 451-03-9/2021-14/200002 and the Science Fund of the Republic of Serbia, PROMIS 6060916, BOWIE (M.S.). This work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. \n\nFacilities: ESO-VLT - , Swift (BAT). - \n\nSoftware: astropy (Astropy Collaboration et al. 2013), Matplotlib (Hunter 2007), NumPy (van der Walt et al. 2011), Linmix (https://github.com/jmeyers314/linmix), PySpecKit v0.1.20 (Ginsburg & Mirocha 2011), ESO Reflex software v2.9.3 (Freudling et al. 2013), molecfit v1.5.9 (Kausch et al. 2015; Smette et al. 2015).\n\nPublished - den_Brok_2022_ApJS_261_7.pdf
Accepted Version - 2207.12426.pdf
",
"abstract": "We present the BAT AGN Spectroscopic Survey (BASS) Near-infrared Data Release 2 (DR2), a study of 168 nearby (z\u0305 = 0.04, z < 0.6) active galactic nuclei (AGN) from the all-sky Swift Burst Array Telescope X-ray survey observed with Very Large Telescope (VLT)/X-shooter in the near-infrared (NIR; 0.8 - 2.4 \u03bcm). We find that 49/109 (45%) Seyfert 2 and 35/58 (60%) Seyfert 1 galaxies observed with VLT/X-shooter show at least one NIR high-ionization coronal line (CL, ionization potential \u03c7 > 100 eV). Comparing the emission of the [Si vi] \u03bb1.9640 CL with the X-ray emission for the DR2 AGN, we find a significantly tighter correlation, with a lower scatter (0.37 dex) than for the optical [O iii] \u03bb5007 line (0.71 dex). We do not find any correlation between CL emission and the X-ray photon index \u0393. We find a clear trend of line blueshifts with increasing ionization potential in several CLs, such as [Si vi] \u03bb1.9640, [Si x] \u03bb1.4300, [S viii] \u03bb0.9915, and [S ix] \u03bb1.2520, indicating the radial structure of the CL region. Finally, we find a strong underestimation bias in black hole mass measurements of Sy 1.9 using broad H\u03b1 due to the presence of significant dust obscuration. In contrast, the broad Pa\u03b1 and Pa\u03b2 emission lines are in agreement with the M-\u03c3 relation. Based on the combined DR1 and DR2 X-shooter sample, the NIR BASS sample now comprises 266 AGN with rest-frame NIR spectroscopic observations, the largest set assembled to date.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 7",
"id_number": "CaltechAUTHORS:20220727-37095000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-37095000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0749"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "726384"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "Comunidad de Madrid",
"grant_number": "2018-T1/TIC-11035"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Swiss National Science Foundation (SNSF)",
"grant_number": "PP00P2_163824"
},
{
"agency": "Swiss National Science Foundation (SNSF)",
"grant_number": "PP00P2_190092"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "864361"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3180506"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "312036/2019-1"
},
{
"agency": "Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)"
},
{
"agency": "Ministry of Education, Science and Technological Development (Serbia)",
"grant_number": "451-03-9/2021-14/200002"
},
{
"agency": "Science Fund (Serbia)",
"grant_number": "6060916"
},
{
"agency": "NSF",
"grant_number": "PHY-1607611"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac5b66",
"primary_object": {
"basename": "2207.12426.pdf",
"url": "https://authors.library.caltech.edu/records/k8k4m-pga96/files/2207.12426.pdf"
},
"related_objects": [
{
"basename": "den_Brok_2022_ApJS_261_7.pdf",
"url": "https://authors.library.caltech.edu/records/k8k4m-pga96/files/den_Brok_2022_ApJS_261_7.pdf"
}
],
"pub_year": "2022",
"author_list": "den Brok, Jakob S.; Koss, Michael J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/rjz0t-3cv46",
"eprint_id": 115882,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:39:48",
"lastmod": "2025-11-20 21:06:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ananna-Tonima-Tasnim",
"name": {
"family": "Ananna",
"given": "Tonima Tasnim"
},
"orcid": "0000-0001-8211-3807"
},
{
"id": "Weigel-Anna-K",
"name": {
"family": "Weigel",
"given": "Anna K."
},
"orcid": "0000-0002-5489-4316"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Hickox-Ryan-C",
"name": {
"family": "Hickox",
"given": "Ryan C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Ueda-Yoshihiro",
"name": {
"family": "Ueda",
"given": "Yoshihiro"
},
"orcid": "0000-0001-7821-6715"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob"
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
},
"orcid": "0000-0002-9144-2255"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Wong-O-Ivy",
"name": {
"family": "Wong",
"given": "O. Ivy"
},
"orcid": "0000-0003-4264-3509"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
}
]
},
"title": "BASS. XXX. Distribution Functions of DR2 Eddington Ratios, Black Hole Masses, and X-Ray Luminosities",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Supermassive black holes; Quasars; Active galactic nuclei; High energy astrophysics; Active galaxies; X-ray active galactic nuclei; X-ray surveys; Luminosity function; Accretion; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 July 4; revised 2022 January 20; accepted 2022 February 5; published 2022 July 15. \n\nThe BAT AGN Spectroscopic Survey Data Release 2.\n\nWe thank the anonymous reviewers for their constructive and detailed comments, which helped us improve the quality of this paper. T.T.A. and R.C.H. acknowledge support from NASA, through ADAP award 80NSSC19K0580. R.C.H. also acknowledges support from the National Science Foundation, through CAREER award 1554584. B.T. acknowledges support from the Israel Science Foundation (grant No. 1849/19) and from the European Research Council (ERC), under the European Union's Horizon 2020 research and innovation program (grant agreement number 950533). M.K. acknowledges support from NASA, through ADAP award NNH16CT03C. C.M.U. acknowledges support from the National Science Foundation, under grant No. AST-1715512. C.R. acknowledges support from the Fondecyt Iniciacion, grant 11190831. We acknowledge support from ANID-Chile Basal AFB-170002 and FB210003 (E.T., F.E.B.), FONDECYT Regular 1200495 and 1190818 (E.T., F.E.B.), ANID Anillo ACT172033 (E.T.), Millennium Nucleus NCN19_058 (TITANs; E.T.), and the Millennium Science Initiative Program\u2014ICN12_009 (F.E.B.). K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). The work of K.I. is supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (18K13584, 20H01939). J.d.B. acknowledges funding from the European Research Council (ERC), under the European Union's Horizon 2020 research and innovation program (grant agreement No.726384/Empire). This work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. \n\nThis research made use of Astropy (Astropy Collaboration et al. 2013; Price-Whelan et al. 2018), Matplotlib (Hunter 2007), Emcee (Foreman-Mackey et al. 2013), NumPy (van der Walt et al. 2011), Topcat (Taylor 2005), xpec and pyxpsec (Arnaud 1996), and ChainConsumer (Hinton 2016).\n\nPublished - Ananna_2022_ApJS_261_9.pdf
Accepted Version - 2201.05603.pdf
",
"abstract": "We determine the low-redshift X-ray luminosity function, active black hole mass function (BHMF), and Eddington ratio distribution function (ERDF) for both unobscured (Type 1) and obscured (Type 2) active galactic nuclei (AGNs), using the unprecedented spectroscopic completeness of the BAT AGN Spectroscopic Survey (BASS) data release 2. In addition to a straightforward 1/V\u2098\u2090\u2093 approach, we also compute the intrinsic distributions, accounting for sample truncation by employing a forward-modeling approach to recover the observed BHMF and ERDF. As previous BHMFs and ERDFs have been robustly determined only for samples of bright, broad-line (Type 1) AGNs and/or quasars, ours are the first directly observationally constrained BHMF and ERDF of Type 2 AGNs. We find that after accounting for all observational biases, the intrinsic ERDF of Type 2 AGNs is significantly more skewed toward lower Eddington ratios than the intrinsic ERDF of Type 1 AGNs. This result supports the radiation-regulated unification scenario, in which radiation pressure dictates the geometry of the dusty obscuring structure around an AGN. Calculating the ERDFs in two separate mass bins, we verify that the derived shape is consistent, validating the assumption that the ERDF (shape) is mass-independent. We report the local AGN duty cycle as a function of mass and Eddington ratio, by comparing the BASS active BHMF with the local mass function for all supermassive black holes. We also present the log N \u2212 log S of the Swift/BAT 70 month sources.",
"date": "2022-07",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "261",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 9",
"id_number": "CaltechAUTHORS:20220727-44653000",
"issn": "0067-0049",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220727-44653000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K0580"
},
{
"agency": "NSF",
"grant_number": "AST-1554584"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "NSF",
"grant_number": "AST-1715512"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18K13584"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "20H01939"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "726384"
},
{
"agency": "NSF",
"grant_number": "PHY-1607611"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ac5b64",
"primary_object": {
"basename": "2201.05603.pdf",
"url": "https://authors.library.caltech.edu/records/rjz0t-3cv46/files/2201.05603.pdf"
},
"related_objects": [
{
"basename": "Ananna_2022_ApJS_261_9.pdf",
"url": "https://authors.library.caltech.edu/records/rjz0t-3cv46/files/Ananna_2022_ApJS_261_9.pdf"
}
],
"pub_year": "2022",
"author_list": "Ananna, Tonima Tasnim; Weigel, Anna K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z1wnp-0py89",
"eprint_id": 115446,
"eprint_status": "archive",
"datestamp": "2023-08-20 08:07:31",
"lastmod": "2025-11-20 20:39:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mallick-Labani",
"name": {
"family": "Mallick",
"given": "L."
},
"orcid": "0000-0001-8624-9162"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "J. A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Wilkins-Dan-R",
"name": {
"family": "Wilkins",
"given": "D. R."
},
"orcid": "0000-0002-4794-5998"
},
{
"id": "De-Marco-Barbara",
"name": {
"family": "De Marco",
"given": "B."
},
"orcid": "0000-0003-2743-6632"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "J. F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "R. M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "G."
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Markowitz-Alex",
"name": {
"family": "Markowitz",
"given": "A. G."
},
"orcid": "0000-0002-2173-0673"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "A. M."
}
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
}
]
},
"title": "High-density disc reflection spectroscopy of low-mass active galactic nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, black hole physics, relativistic processes, galaxies: active, galaxies: nuclei, X-rays: galaxies",
"note": "\u00a9 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nAccepted 2022 April 5. Received 2022 April 5; in original form 2021 December 9. \n\nLM is supported by NASA ADAP grant 80NSSC21K1567. JAG acknowledges support from NASA grant 80NSSC21K1567 and from the Alexander von Humboldt Foundation. JAT acknowledges partial support from NASA ADAP grant 80NSSC19K0586. BDM acknowledges support via Ram\u00f3n y Cajal Fellowship RYC2018-025950-I. AGM acknowledges partial support from Polish National Science Center (NCN) grant numbers 2016/23/B/ST9/03123 and 2018/31/G/ST9/03224. We thank the anonymous reviewer for a constructive report. We dedicate this paper to doctors and nurses fighting the COVID-19 global pandemic. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the NASA. This research has made use of data, software and/or web tools obtained from the High Energy Astrophysics Science Archive Research Center (HEASARC), a service of the Astrophysics Science Division at NASA/GSFC and of the Smithsonian Astrophysical Observatory's High Energy Astrophysics Division. \n\nDATA AVAILABILITY. All the data used in this article are publicly available from ESA XMM\u2013Newton Science Archive (XSA; http://nxsa.esac.esa.int/) and NASA High Energy Astrophysics Science Archive Research Center (HEASARC; https://heasarc.gsfc.nasa.gov/).\n\nPublished - stac990.pdf
Accepted Version - 2203.04522.pdf
",
"abstract": "The standard alpha-disc model predicts an anticorrelation between the density of the inner accretion disc and the black hole mass times square of the accretion rate, as seen in higher mass (M_(BH) > 10\u2076\u2009M_\u2299) active galactic nuclei (AGNs). In this work, we test the predictions of the alpha-disc model and study the properties of the inner accretion flow for the low-mass end (M_(BH) \u2248 10\u2075\u207b\u2076\u2009M_\u2299) of AGNs. We utilize a new high-density disc reflection model where the density parameter varies from n\u2091 = 10\u00b9\u2075 to 10\u00b2\u2070 cm\u207b\u00b3 and apply it to the broad-band X-ray (0.3\u201310 keV) spectra of the low-mass AGN sample. The sources span a wide range of Eddington fractions and are consistent with being sub-Eddington or near-Eddington. The X-ray spectra reveal a soft X-ray excess below \u223c1.5 keV which is well modelled by high-density reflection from an ionized accretion disc of density ne \u223c 10\u00b9\u2078 cm\u207b\u00b3 on average. The results suggest a radiation pressure-dominated disc with an average of 70 per cent fraction of the disc power transferred to the corona, consistent with that observed in higher mass AGNs. We show that the disc density higher than 10\u00b9\u2075 cm\u207b\u00b3 can result from the radiation pressure compression when the disc surface does not hold a strong magnetic pressure gradient. We find tentative evidence for a drop in black hole spin at low-mass regimes.",
"date": "2022-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "513",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "4361-4379",
"id_number": "CaltechAUTHORS:20220709-032308938",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220709-032308938",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC21K1567"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Ram\u00f3n y Cajal Programme",
"grant_number": "RYC2018-025950-I"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2016/23/B/ST9/03123"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2018/31/G/ST9/03224"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac990",
"primary_object": {
"basename": "2203.04522.pdf",
"url": "https://authors.library.caltech.edu/records/z1wnp-0py89/files/2203.04522.pdf"
},
"related_objects": [
{
"basename": "stac990.pdf",
"url": "https://authors.library.caltech.edu/records/z1wnp-0py89/files/stac990.pdf"
}
],
"pub_year": "2022",
"author_list": "Mallick, L.; Fabian, A. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ppsv7-wbf35",
"eprint_id": 114825,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:54:35",
"lastmod": "2025-11-20 21:05:58",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Fahr-H",
"name": {
"family": "Fahr",
"given": "H."
}
},
{
"id": "Fichtner-H",
"name": {
"family": "Fichtner",
"given": "H."
}
},
{
"id": "Florinski-Vladimir",
"name": {
"family": "Florinski",
"given": "V."
},
"orcid": "0000-0001-5485-2872"
},
{
"id": "Heber-Bernd",
"name": {
"family": "Heber",
"given": "B."
},
"orcid": "0000-0003-0960-5658"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "K\u00f3ta-Jozsef",
"name": {
"family": "K\u00f3ta",
"given": "J."
},
"orcid": "0000-0002-3715-0358"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Potgieter-M-S",
"name": {
"family": "Potgieter",
"given": "M. S."
}
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
}
]
},
"title": "Anomalous Cosmic Rays and Heliospheric Energetic Particles",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Particle acceleration \u00b7 Cosmic rays \u00b7 Shocks \u00b7 Cosmic ray transport \u00b7 Pickup ions \u00b7 Heliosphere; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nAccepted: 4 April 2022. \n\nWe are grateful to the International Space Science Institute for their organization, hosting, and support of the workshop \"The Heliosphere in the Local Interstellar Medium\", made especially challenging due to the coronavirus pandemic. JG acknowledges partial travel support to attend the meeting from USRA/Lunar and Planetary Institute. JG also acknowledges support from NASA grant 18-DRIVE18_2-0029 as part of the NASA/DRIVE program titled \"Our Heliospheric Shield\", and from NASA's Interstellar Mapping and Acceleration Probe (IMAP) under NASA contract 80GSFC19C0027. \n\nOpen Access funding enabled and organized by Projekt DEAL.\n\nPublished - s11214-022-00890-7.pdf
",
"abstract": "We present a review of Anomalous Cosmic Rays (ACRs), including the history of their discovery and recent insights into their acceleration and transport in the heliosphere. We focus on a few selected topics including a discussion of mechanisms of their acceleration, escape from the heliosphere, their effects on the dynamics of the heliosheath, transport in the inner heliosphere, and their solar cycle dependence. A\u00a0discussion concerning their name is also presented towards the end of the review. We note that much is known about ACRs and perhaps the term Anomalous Cosmic Ray is not particularly descriptive to a non specialist. We suggest that the more-general term: \"Heliospheric Energetic Particles\", which is more descriptive, for which ACRs and other energetic particle species of heliospheric origin are subsets, might be more appropriate.",
"date": "2022-06",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "218",
"number": "4",
"publisher": "Springer",
"pagerange": "Art. No. 22",
"id_number": "CaltechAUTHORS:20220520-648897000",
"issn": "0038-6308",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220520-648897000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Universities Space Research Association"
},
{
"agency": "Lunar and Planetary Institute"
},
{
"agency": "NASA",
"grant_number": "18-DRIVE18_2-0029"
},
{
"agency": "NASA",
"grant_number": "80GSFC19C0027"
},
{
"agency": "Projekt DEAL"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1007/s11214-022-00890-7",
"pmcid": "PMC9046724",
"primary_object": {
"basename": "s11214-022-00890-7.pdf",
"url": "https://authors.library.caltech.edu/records/ppsv7-wbf35/files/s11214-022-00890-7.pdf"
},
"pub_year": "2022",
"author_list": "Giacalone, J.; Fahr, H.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tnxbk-2xz73",
"eprint_id": 114917,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:55:08",
"lastmod": "2025-11-20 20:32:19",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yerong",
"name": {
"family": "Xu",
"given": "Y."
},
"orcid": "0000-0002-2523-5485"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Masterson-Megan",
"name": {
"family": "Masterson",
"given": "M."
},
"orcid": "0000-0003-4127-0739"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Cusumano-Giancarlo",
"name": {
"family": "Cusumano",
"given": "G."
},
"orcid": "0000-0002-8151-1990"
}
]
},
"title": "Ejection\u2013accretion connection in NLS1 AGN 1H 1934-063",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, black hole physics, galaxies: Seyfert, X-rays: individual: 1H 1934-063; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model).\n\nAccepted 2022 April 12. Received 2022 April 6; in original form 2022 March 4. \n\nEK acknowledges support from NASA ADAP grant no. 80NSSC17K0515. JAG acknowledges support from NASA ATP grant no. 80NSSC20K0540 and from the Alexander von Humboldt Foundation. WNA is supported by an ESA research fellowship. \n\nDATA AVAILABILITY. The XMM\u2013Newton and NuSTAR data underlying this article are available in ESA's XMM\u2013Newton Science Archive (https://www.cosmos.esa.int/web/xmm-newton/xsa) and HEASARC NuSTAR Archive, respectively.\n\nPublished - stac1058.pdf
Accepted Version - 2204.06075.pdf
",
"abstract": "Accretion and ejection of matter in active galactic nuclei (AGNs) are tightly connected phenomena and represent fundamental mechanisms regulating the growth of the central supermassive black hole and the evolution of the host galaxy. However, the exact physical processes involved are not yet fully understood. We present a high-resolution spectral analysis of a simultaneous XMM\u2013Newton and NuSTAR observation of the narrow line Seyfert 1 (NLS1) AGN 1H 1934-063, during which the X-ray flux dropped by a factor of \u223c6 and subsequently recovered within 140 kiloseconds. By means of the time-resolved and flux-resolved X-ray spectroscopy, we discover a potentially variable warm absorber and a relatively stable ultra-fast outflow (UFO, \u03bd_(UFO) ~ -0.075 c) with a mild ionization state (log \u03be/erg cm s\u207b\u00b9) ~ 1.6). The detected emission lines (especially a strong and broad feature around 1\u2009keV) are of unknown origin and cannot be explained with emission from plasmas in photo- or collisional-ionization equilibrium. Such emission lines could be well described by a strongly blueshifted (z \u223c \u22120.3) secondary reflection off the base of the equatorial outflows, which may reveal the link between the reprocessing of the inner accretion flow photons and the ejection. However, this scenario although being very promising is only tentative and will be tested with future observations.",
"date": "2022-06",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "513",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "1910-1924",
"id_number": "CaltechAUTHORS:20220525-90819000",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220525-90819000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0540"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "European Space Agency (ESA)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac1058",
"primary_object": {
"basename": "2204.06075.pdf",
"url": "https://authors.library.caltech.edu/records/tnxbk-2xz73/files/2204.06075.pdf"
},
"related_objects": [
{
"basename": "stac1058.pdf",
"url": "https://authors.library.caltech.edu/records/tnxbk-2xz73/files/stac1058.pdf"
}
],
"pub_year": "2022",
"author_list": "Xu, Y.; Pinto, C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zaj7r-1sm48",
"eprint_id": 115832,
"eprint_status": "archive",
"datestamp": "2023-08-22 16:07:57",
"lastmod": "2025-11-21 02:21:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zank-Gary-P",
"name": {
"family": "Zank",
"given": "G. P."
},
"orcid": "0000-0002-4642-6192"
},
{
"id": "Sterken-V",
"name": {
"family": "Sterken",
"given": "V."
},
"orcid": "0000-0003-0843-7912"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "M\u00f6bius-E",
"name": {
"family": "M\u00f6bius",
"given": "E."
}
},
{
"id": "von-Steiger-R",
"name": {
"family": "von Steiger",
"given": "R."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. S."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Krimigis-Stamatios-M",
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Richardson-Jonathan-W",
"name": {
"family": "Richardson",
"given": "J. W."
},
"orcid": "0000-0002-1472-4806"
},
{
"id": "Linsky-Jeffrey-L",
"name": {
"family": "Linsky",
"given": "J."
},
"orcid": "0000-0003-4446-3181"
},
{
"id": "Izmodenov-V",
"name": {
"family": "Izmodenov",
"given": "V."
}
},
{
"id": "Heber-Bernd",
"name": {
"family": "Heber",
"given": "B."
},
"orcid": "0000-0003-0960-5658"
}
]
},
"title": "The Early History of Heliospheric Science and the Spacecraft That Made It Possible",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliosphere \u00b7 Interstellar medium; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived: 2 March 2022 / Accepted: 2 May 2022 / Published online: 25 May 2022. \n\nGPZ acknowledges the partial support of an NSF EPSCoR RII-Track-1 Cooperative Agreement OIA-1655280, a NASA IBEX award 80NSSC20K0719, a NASA IMAP subaward under NASA contract 80GSFC19C0027, and a BU NASA DRIVE award 80NSSC20K0603. V.J. Sterken received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N 851544. \n\nOpen access funding provided by Swiss Federal Institute of Technology Zurich.\n\nPublished - Zank2022_Article_TheEarlyHistoryOfHeliosphericS.pdf
",
"abstract": "Our understanding of the interaction of the large-scale heliosphere with the local interstellar medium (LISM) has undergone a profound change since the very earliest analyses of the problem. In part, the revisions have been a consequence of ever-improving and widening observational results, especially those that identified the entrance of interstellar material and gas into the heliosphere. Accompanying these observations was the identification of the basic underlying physics of how neutral interstellar gas and interstellar charged particles of different energies, up to and including interstellar dust grains, interacted with the temporal flows and electromagnetic fields of the heliosphere. The incorporation of these various basic effects into global models of the interaction, whether focused on neutral interstellar gas and pickup ions, energetic particles such as anomalous and galactic cosmic rays, or magnetic fields and large-scale flows, has profoundly changed our view of how the heliosphere and LISM interact. This article presents a brief history of the conceptual and observation evolution of our understanding of the interaction of the heliosphere with the local interstellar medium, up until approximately 1996.",
"date": "2022-06",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "218",
"number": "4",
"publisher": "Springer",
"pagerange": "Art. No. 34",
"id_number": "CaltechAUTHORS:20220725-156819000",
"issn": "0038-6308",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220725-156819000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "OIA-1655280"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0719"
},
{
"agency": "NASA",
"grant_number": "80GSFC19C0027"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0603"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "851544"
},
{
"agency": "ETH Zurich"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1007/s11214-022-00900-8",
"primary_object": {
"basename": "Zank2022_Article_TheEarlyHistoryOfHeliosphericS.pdf",
"url": "https://authors.library.caltech.edu/records/zaj7r-1sm48/files/Zank2022_Article_TheEarlyHistoryOfHeliosphericS.pdf"
},
"pub_year": "2022",
"author_list": "Zank, G. P.; Sterken, V.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dsyz3-zaq30",
"eprint_id": 114736,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:34:07",
"lastmod": "2025-11-20 20:38:54",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walsh-Nathan-E",
"name": {
"family": "Walsh",
"given": "Nathan Elliot"
}
},
{
"name": {
"family": "Akaike",
"given": "Yosui"
},
"orcid": "0000-0002-9489-1515"
},
{
"name": {
"family": "Binns",
"given": "Walter Robert"
},
"orcid": "0000-0001-6110-3407"
},
{
"name": {
"family": "Bose",
"given": "Richard G."
}
},
{
"name": {
"family": "Brandt",
"given": "Terri J."
},
"orcid": "0000-0003-4087-1786"
},
{
"name": {
"family": "Braun",
"given": "Dana L."
}
},
{
"name": {
"family": "Cannady",
"given": "Nicholas W."
},
"orcid": "0000-0003-2916-6955"
},
{
"name": {
"family": "Dowkontt",
"given": "Paul F."
}
},
{
"name": {
"family": "Hams",
"given": "Thomas"
}
},
{
"name": {
"family": "Israel",
"given": "Martin H."
},
"orcid": "0000-0002-8104-208X"
},
{
"name": {
"family": "Krizmanic",
"given": "John F."
}
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "Allan W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "Richard A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "John W."
}
},
{
"name": {
"family": "Murphy",
"given": "Ryan P."
}
},
{
"name": {
"family": "de Nolfo",
"given": "Georgia A."
},
"orcid": "0000-0002-3677-074X"
},
{
"name": {
"family": "Nutter",
"given": "Scott"
},
"orcid": "0000-0002-1794-3836"
},
{
"name": {
"family": "Olevitch",
"given": "Martin A."
}
},
{
"name": {
"family": "Rauch",
"given": "Brian. F."
},
"orcid": "0000-0002-1452-4142"
},
{
"name": {
"family": "Sakai",
"given": "Kenichi"
}
},
{
"name": {
"family": "Sasaki",
"given": "Makoto"
}
},
{
"name": {
"family": "Simburger",
"given": "Garry E."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Ed C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Tatoli",
"given": "Teresa"
}
},
{
"name": {
"family": "Ward",
"given": "John Ennis"
},
"orcid": "0000-0003-1973-0794"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "Mark E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Zober",
"given": "Wolfgang V."
}
}
]
},
"title": "SuperTIGER instrument abundances of galactic cosmic rays for the charge interval 41 \u2a7d Z \u2264 56",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galactic cosmic rays; supernova; binary neutron star merger; long-duration balloon; Antarctica; Space and Planetary Science; Aerospace Engineering; General Earth and Planetary Sciences; Atmospheric Science; Geophysics; Astronomy and Astrophysics",
"note": "\u00a9 2022 COSPAR. Published by Elsevier. \n\nReceived 1 November 2021, Revised 22 March 2022, Accepted 26 April 2022, Available online 10 May 2022. \n\nThis research was supported by NASA under grants NNX09AC17G, NNX14AB25G, NNX15AC23G and 80NSSC20K0405, by the McDonnell Center for the Space Sciences at Washington University, and by the Peggy and Steve Fossett Foundation. \n\nWe thank the NASA Columbia Scientific Balloon Facility, the NASA Balloon Program Office, and the NSF United States Antarctic Program for the excellent and highly professional efforts that resulted in two successful long-duration balloon flights for SuperTIGER.\n\nAccepted Version - 1-s2.0-S0273117722003404-main.pdf
",
"abstract": "We report preliminary elemental abundance results from the 55-day long-duration-balloon flight of SuperTIGER (Super Trans-Iron Galactic Element Recorder) during the 2012-2013 austral summer. SuperTIGER measured the relative abundances of Galactic cosmic-ray (GCR) nuclei with high statistical precision and well resolved individual element peaks from \u2081\u2080Ne to \u2084\u2080Zr. SuperTIGER also made exploratory measurements of the relative abundances up to \u2085\u2086Ba. Although the statistics are low for elements heavier than \u2084\u2080Zr, we present, for the first time, relative abundance measurements of charges Z = 41-56 with individual element resolution. GCR measurements up to \u2084\u2080Zr support a source acceleration model where supernovae in OB associations preferentially accelerate refractory elements that are more readily embedded in interstellar dust grains than volatiles. In addition, injection into the GCR for both refractory and volatile elements appears to follow a charge dependence consistent with their grain sputtering cross sections. By extending the GCR measurement range past \u2084\u2080Zr, we can begin to further constrain these models.",
"date": "2022-05-16",
"date_type": "published",
"publication": "Advances in Space Research",
"publisher": "Elsevier",
"id_number": "CaltechAUTHORS:20220513-557872000",
"issn": "0273-1177",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220513-557872000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX09AC17G"
},
{
"agency": "NASA",
"grant_number": "NNX14AB25G"
},
{
"agency": "NASA",
"grant_number": "NNX15AC23G"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0405"
},
{
"agency": "Washington University"
},
{
"agency": "Peggy and Steve Fossett Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1016/j.asr.2022.04.063",
"primary_object": {
"basename": "1-s2.0-S0273117722003404-main.pdf",
"url": "https://authors.library.caltech.edu/records/dsyz3-zaq30/files/1-s2.0-S0273117722003404-main.pdf"
},
"pub_year": "2022",
"author_list": "Walsh, Nathan Elliot; Akaike, Yosui; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9c3m1-t3d06",
"eprint_id": 114717,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:33:43",
"lastmod": "2025-11-21 04:20:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Akiyama-Kazunori",
"name": {
"family": "Akiyama",
"given": "Kazunori"
},
"orcid": "0000-0002-9475-4254"
},
{
"name": {
"family": "Alberdi",
"given": "Antxon"
},
"orcid": "0000-0002-9371-1033"
},
{
"name": {
"family": "Alef",
"given": "Walter"
}
},
{
"name": {
"family": "Algaba",
"given": "Juan Carlos"
},
"orcid": "0000-0001-6993-1696"
},
{
"name": {
"family": "Anantua",
"given": "Richard"
},
"orcid": "0000-0003-3457-7660"
},
{
"name": {
"family": "Asada",
"given": "Keiichi"
},
"orcid": "0000-0001-6988-8763"
},
{
"name": {
"family": "Azulay",
"given": "Rebecca"
},
"orcid": "0000-0002-2200-5393"
},
{
"name": {
"family": "Bach",
"given": "Uwe"
},
"orcid": "0000-0002-7722-8412"
},
{
"name": {
"family": "Baczko",
"given": "Anne-Kathrin"
},
"orcid": "0000-0003-3090-3975"
},
{
"name": {
"family": "Ball",
"given": "David"
}
},
{
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"name": {
"family": "Barrett",
"given": "John"
},
"orcid": "0000-0002-9290-0764"
},
{
"name": {
"family": "Baub\u00f6ck",
"given": "Michi"
},
"orcid": "0000-0002-5518-2812"
},
{
"name": {
"family": "Benson",
"given": "Bradford A."
},
"orcid": "0000-0002-5108-6823"
},
{
"name": {
"family": "Bintley",
"given": "Dan"
}
},
{
"name": {
"family": "Blackburn",
"given": "Lindy"
},
"orcid": "0000-0002-9030-642X"
},
{
"name": {
"family": "Blundell",
"given": "Raymond"
},
"orcid": "0000-0002-5929-5857"
},
{
"id": "Bouman-K-L",
"name": {
"family": "Bouman",
"given": "Katherine L."
},
"orcid": "0000-0003-0077-4367"
},
{
"name": {
"family": "Bower",
"given": "Geoffrey C."
},
"orcid": "0000-0003-4056-9982"
},
{
"name": {
"family": "Boyce",
"given": "Hope"
},
"orcid": "0000-0002-6530-5783"
},
{
"name": {
"family": "Bremer",
"given": "Michael"
}
},
{
"name": {
"family": "Brinkerink",
"given": "Christiaan D."
},
"orcid": "0000-0002-2322-0749"
},
{
"name": {
"family": "Brissenden",
"given": "Roger"
},
"orcid": "0000-0002-2556-0894"
},
{
"name": {
"family": "Britzen",
"given": "Silke"
},
"orcid": "0000-0001-9240-6734"
},
{
"name": {
"family": "Broderick",
"given": "Avery E."
},
"orcid": "0000-0002-3351-760X"
},
{
"name": {
"family": "Broguiere",
"given": "Dominique"
},
"orcid": "0000-0001-9151-6683"
},
{
"name": {
"family": "Bronzwaer",
"given": "Thomas"
},
"orcid": "0000-0003-1151-3971"
},
{
"name": {
"family": "Bustamante",
"given": "Sandra"
},
"orcid": "0000-0001-6169-1894"
},
{
"name": {
"family": "Byun",
"given": "Do-Young"
},
"orcid": "0000-0003-1157-4109"
},
{
"name": {
"family": "Carlstrom",
"given": "John E."
},
"orcid": "0000-0002-2044-7665"
},
{
"name": {
"family": "Ceccobello",
"given": "Chiara"
},
"orcid": "0000-0002-4767-9925"
},
{
"name": {
"family": "Chael",
"given": "Andrew"
},
"orcid": "0000-0003-2966-6220"
},
{
"name": {
"family": "Chan",
"given": "Chi-kwan"
},
"orcid": "0000-0001-6337-6126"
},
{
"name": {
"family": "Chatterjee",
"given": "Koushik"
},
"orcid": "0000-0002-2825-3590"
},
{
"name": {
"family": "Chatterjee",
"given": "Shami"
},
"orcid": "0000-0002-2878-1502"
},
{
"name": {
"family": "Chen",
"given": "Ming-Tang"
},
"orcid": "0000-0001-6573-3318"
},
{
"name": {
"family": "Chen",
"given": "Yongjun"
},
"orcid": "0000-0001-5650-6770"
},
{
"name": {
"family": "Cheng",
"given": "Xiaopeng"
},
"orcid": "0000-0003-4407-9868"
},
{
"name": {
"family": "Cho",
"given": "Ilje"
},
"orcid": "0000-0001-6083-7521"
},
{
"name": {
"family": "Christian",
"given": "Pierre"
},
"orcid": "0000-0001-6820-9941"
},
{
"name": {
"family": "Conroy",
"given": "Nicholas S."
},
"orcid": "0000-0003-2886-2377"
},
{
"name": {
"family": "Conway",
"given": "John E."
},
"orcid": "0000-0003-2448-9181"
},
{
"name": {
"family": "Cordes",
"given": "James M."
},
"orcid": "0000-0002-4049-1882"
},
{
"name": {
"family": "Crawford",
"given": "Thomas M."
},
"orcid": "0000-0001-9000-5013"
},
{
"name": {
"family": "Crew",
"given": "Geoffrey B."
},
"orcid": "0000-0002-2079-3189"
},
{
"name": {
"family": "Cruz-Osorio",
"given": "Alejandro"
},
"orcid": "0000-0002-3945-6342"
},
{
"name": {
"family": "Cui",
"given": "Yuzhu"
},
"orcid": "0000-0001-6311-4345"
},
{
"name": {
"family": "Davelaar",
"given": "Jordy"
},
"orcid": "0000-0002-2685-2434"
},
{
"name": {
"family": "De Laurentis",
"given": "Mariafelicia"
},
"orcid": "0000-0002-9945-682X"
},
{
"name": {
"family": "Deane",
"given": "Roger"
},
"orcid": "0000-0003-1027-5043"
},
{
"name": {
"family": "Dempsey",
"given": "Jessica"
},
"orcid": "0000-0003-1269-9667"
},
{
"name": {
"family": "Desvignes",
"given": "Gregory"
},
"orcid": "0000-0003-3922-4055"
},
{
"name": {
"family": "Dexter",
"given": "Jason"
},
"orcid": "0000-0003-3903-0373"
},
{
"name": {
"family": "Dhruv",
"given": "Vedant"
},
"orcid": "0000-0001-6765-877X"
},
{
"name": {
"family": "Doeleman",
"given": "Sheperd S."
},
"orcid": "0000-0002-9031-0904"
},
{
"name": {
"family": "Dougal",
"given": "Sean"
},
"orcid": "0000-0002-3769-1314"
},
{
"name": {
"family": "Dzib",
"given": "Sergio A."
},
"orcid": "0000-0001-6010-6200"
},
{
"name": {
"family": "Eatough",
"given": "Ralph P."
},
"orcid": "0000-0001-6196-4135"
},
{
"name": {
"family": "Emami",
"given": "Razieh"
},
"orcid": "0000-0002-2791-5011"
},
{
"name": {
"family": "Falcke",
"given": "Heino"
},
"orcid": "0000-0002-2526-6724"
},
{
"name": {
"family": "Farah",
"given": "Joseph"
},
"orcid": "0000-0003-4914-5625"
},
{
"name": {
"family": "Fish",
"given": "Vincent L."
},
"orcid": "0000-0002-7128-9345"
},
{
"name": {
"family": "Fomalont",
"given": "Ed"
},
"orcid": "0000-0002-9036-2747"
},
{
"name": {
"family": "Ford",
"given": "H. Alyson"
},
"orcid": "0000-0002-9797-0972"
},
{
"name": {
"family": "Fraga-Encinas",
"given": "Raquel"
},
"orcid": "0000-0002-5222-1361"
},
{
"name": {
"family": "Freeman",
"given": "William T."
},
"orcid": "0000-0002-2231-7995"
},
{
"name": {
"family": "Friberg",
"given": "Per"
},
"orcid": "0000-0002-8010-8454"
},
{
"name": {
"family": "Fromm",
"given": "Christian M."
},
"orcid": "0000-0002-1827-1656"
},
{
"name": {
"family": "Fuentes",
"given": "Antonio"
},
"orcid": "0000-0002-8773-4933"
},
{
"name": {
"family": "Galison",
"given": "Peter"
},
"orcid": "0000-0002-6429-3872"
},
{
"name": {
"family": "Gammie",
"given": "Charles F."
},
"orcid": "0000-0001-7451-8935"
},
{
"name": {
"family": "Garc\u00eda",
"given": "Roberto"
},
"orcid": "0000-0002-6584-7443"
},
{
"name": {
"family": "Gentaz",
"given": "Olivier"
},
"orcid": "0000-0002-0115-4605"
},
{
"name": {
"family": "Georgiev",
"given": "Boris"
},
"orcid": "0000-0002-3586-6424"
},
{
"name": {
"family": "Goddi",
"given": "Ciriaco"
},
"orcid": "0000-0002-2542-7743"
},
{
"name": {
"family": "Gold",
"given": "Roman"
},
"orcid": "0000-0003-2492-1966"
},
{
"name": {
"family": "G\u00f3mez-Ruiz",
"given": "Arturo I."
},
"orcid": "0000-0001-9395-1670"
},
{
"name": {
"family": "G\u00f3mez",
"given": "Jos\u00e9 L."
},
"orcid": "0000-0003-4190-7613"
},
{
"name": {
"family": "Gu",
"given": "Minfeng"
},
"orcid": "0000-0002-4455-6946"
},
{
"name": {
"family": "Gurwell",
"given": "Mark"
},
"orcid": "0000-0003-0685-3621"
},
{
"name": {
"family": "Hada",
"given": "Kazuhiro"
},
"orcid": "0000-0001-6906-772X"
},
{
"name": {
"family": "Haggard",
"given": "Daryl"
},
"orcid": "0000-0001-6803-2138"
},
{
"name": {
"family": "Haworth",
"given": "Kari"
}
},
{
"name": {
"family": "Hecht",
"given": "Michael H."
},
"orcid": "0000-0002-4114-4583"
},
{
"name": {
"family": "Hesper",
"given": "Ronald"
},
"orcid": "0000-0003-1918-6098"
},
{
"name": {
"family": "Heumann",
"given": "Dirk"
},
"orcid": "0000-0002-7671-0047"
},
{
"name": {
"family": "Ho",
"given": "Luis C."
},
"orcid": "0000-0001-6947-5846"
},
{
"name": {
"family": "Ho",
"given": "Paul"
},
"orcid": "0000-0002-3412-4306"
},
{
"name": {
"family": "Honma",
"given": "Mareki"
},
"orcid": "0000-0003-4058-9000"
},
{
"name": {
"family": "Huang",
"given": "Chih-Wei L."
},
"orcid": "0000-0001-5641-3953"
},
{
"name": {
"family": "Huang",
"given": "Lei"
},
"orcid": "0000-0002-1923-227X"
},
{
"name": {
"family": "Hughes",
"given": "David H."
}
},
{
"name": {
"family": "Ikeda",
"given": "Shiro"
},
"orcid": "0000-0002-2462-1448"
},
{
"name": {
"family": "Impellizzeri",
"given": "C. M. Violette"
},
"orcid": "0000-0002-3443-2472"
},
{
"name": {
"family": "Inoue",
"given": "Makoto"
},
"orcid": "0000-0001-5037-3989"
},
{
"name": {
"family": "Issaoun",
"given": "Sara"
},
"orcid": "0000-0002-5297-921X"
},
{
"name": {
"family": "James",
"given": "David J."
},
"orcid": "0000-0001-5160-4486"
},
{
"name": {
"family": "Jannuzi",
"given": "Buell T."
},
"orcid": "0000-0002-1578-6582"
},
{
"name": {
"family": "Janssen",
"given": "Michael"
},
"orcid": "0000-0001-8685-6544"
},
{
"name": {
"family": "Jeter",
"given": "Britton"
},
"orcid": "0000-0003-2847-1712"
},
{
"name": {
"family": "Jiang",
"given": "Wu"
},
"orcid": "0000-0001-7369-3539"
},
{
"name": {
"family": "Jim\u00e9nez-Rosales",
"given": "Alejandra"
},
"orcid": "0000-0002-2662-3754"
},
{
"name": {
"family": "Johnson",
"given": "Michael D."
},
"orcid": "0000-0002-4120-3029"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana"
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Joshi",
"given": "Abhishek V."
},
"orcid": "0000-0002-2514-5965"
},
{
"name": {
"family": "Jung",
"given": "Taehyun"
},
"orcid": "0000-0001-7003-8643"
},
{
"name": {
"family": "Karami",
"given": "Mansour"
},
"orcid": "0000-0001-7387-9333"
},
{
"name": {
"family": "Karuppusamy",
"given": "Ramesh"
},
"orcid": "0000-0002-5307-2919"
},
{
"name": {
"family": "Kawashima",
"given": "Tomohisa"
},
"orcid": "0000-0001-8527-0496"
},
{
"name": {
"family": "Keating",
"given": "Garrett K."
},
"orcid": "0000-0002-3490-146X"
},
{
"name": {
"family": "Kettenis",
"given": "Mark"
},
"orcid": "0000-0002-6156-5617"
},
{
"name": {
"family": "Kim",
"given": "Dong-Jin"
},
"orcid": "0000-0002-7038-2118"
},
{
"name": {
"family": "Kim",
"given": "Jae-Young"
},
"orcid": "0000-0001-8229-7183"
},
{
"name": {
"family": "Kim",
"given": "Jongsoo"
},
"orcid": "0000-0002-1229-0426"
},
{
"id": "Kim-Junhan",
"name": {
"family": "Kim",
"given": "Junhan"
},
"orcid": "0000-0002-4274-9373"
},
{
"name": {
"family": "Kino",
"given": "Motoki"
},
"orcid": "0000-0002-2709-7338"
},
{
"name": {
"family": "Koay",
"given": "Jun Yi"
},
"orcid": "0000-0002-7029-6658"
},
{
"name": {
"family": "Kocherlakota",
"given": "Prashant"
},
"orcid": "0000-0001-7386-7439"
},
{
"name": {
"family": "Kofuji",
"given": "Yutaro"
}
},
{
"name": {
"family": "Koch",
"given": "Patrick M."
},
"orcid": "0000-0003-2777-5861"
},
{
"name": {
"family": "Koyama",
"given": "Shoko"
},
"orcid": "0000-0002-3723-3372"
},
{
"name": {
"family": "Kramer",
"given": "Carsten"
},
"orcid": "0000-0002-4908-4925"
},
{
"name": {
"family": "Kramer",
"given": "Michael"
},
"orcid": "0000-0002-4175-2271"
},
{
"name": {
"family": "Krichbaum",
"given": "Thomas P."
},
"orcid": "0000-0002-4892-9586"
},
{
"name": {
"family": "Kuo",
"given": "Cheng-Yu"
},
"orcid": "0000-0001-6211-5581"
},
{
"name": {
"family": "Bella",
"given": "Noemi La"
},
"orcid": "0000-0002-8116-9427"
},
{
"name": {
"family": "Lauer",
"given": "Tod R."
},
"orcid": "0000-0003-3234-7247"
},
{
"name": {
"family": "Lee",
"given": "Daeyoung"
},
"orcid": "0000-0002-3350-5588"
},
{
"name": {
"family": "Lee",
"given": "Sang-Sung"
},
"orcid": "0000-0002-6269-594X"
},
{
"name": {
"family": "Leung",
"given": "Po Kin"
},
"orcid": "0000-0002-8802-8256"
},
{
"id": "Levis-Aviad",
"name": {
"family": "Levis",
"given": "Aviad"
},
"orcid": "0000-0001-7307-632X"
},
{
"name": {
"family": "Li",
"given": "Zhiyuan"
},
"orcid": "0000-0003-0355-6437"
},
{
"name": {
"family": "Lico",
"given": "Rocco"
},
"orcid": "0000-0001-7361-2460"
},
{
"name": {
"family": "Lindahl",
"given": "Greg"
},
"orcid": "0000-0002-6100-4772"
},
{
"name": {
"family": "Lindqvist",
"given": "Michael"
},
"orcid": "0000-0002-3669-0715"
},
{
"name": {
"family": "Lisakov",
"given": "Mikhail"
},
"orcid": "0000-0001-6088-3819"
},
{
"name": {
"family": "Liu",
"given": "Jun"
},
"orcid": "0000-0002-7615-7499"
},
{
"name": {
"family": "Liu",
"given": "Kuo"
},
"orcid": "0000-0002-2953-7376"
},
{
"name": {
"family": "Liuzzo",
"given": "Elisabetta"
},
"orcid": "0000-0003-0995-5201"
},
{
"name": {
"family": "Lo",
"given": "Wen-Ping"
},
"orcid": "0000-0003-1869-2503"
},
{
"name": {
"family": "Lobanov",
"given": "Andrei P."
},
"orcid": "0000-0003-1622-1484"
},
{
"name": {
"family": "Loinard",
"given": "Laurent"
},
"orcid": "0000-0002-5635-3345"
},
{
"name": {
"family": "Lonsdale",
"given": "Colin J."
},
"orcid": "0000-0003-4062-4654"
},
{
"name": {
"family": "Lu",
"given": "Ru-Sen"
},
"orcid": "0000-0002-7692-7967"
},
{
"name": {
"family": "Mao",
"given": "Jirong"
},
"orcid": "0000-0002-7077-7195"
},
{
"name": {
"family": "Marchili",
"given": "Nicola"
},
"orcid": "0000-0002-5523-7588"
},
{
"name": {
"family": "Markoff",
"given": "Sera"
},
"orcid": "0000-0001-9564-0876"
},
{
"name": {
"family": "Marrone",
"given": "Daniel P."
},
"orcid": "0000-0002-2367-1080"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Mart\u00ed-Vidal",
"given": "Iv\u00e1n"
},
"orcid": "0000-0003-3708-9611"
},
{
"name": {
"family": "Matsushita",
"given": "Satoki"
},
"orcid": "0000-0002-2127-7880"
},
{
"name": {
"family": "Matthews",
"given": "Lynn D."
},
"orcid": "0000-0002-3728-8082"
},
{
"name": {
"family": "Medeiros",
"given": "Lia"
},
"orcid": "0000-0003-2342-6728"
},
{
"name": {
"family": "Menten",
"given": "Karl M."
},
"orcid": "0000-0001-6459-0669"
},
{
"name": {
"family": "Michalik",
"given": "Daniel"
},
"orcid": "0000-0002-7618-6556"
},
{
"name": {
"family": "Mizuno",
"given": "Izumi"
},
"orcid": "0000-0002-7210-6264"
},
{
"name": {
"family": "Mizuno",
"given": "Yosuke"
},
"orcid": "0000-0002-8131-6730"
},
{
"name": {
"family": "Moran",
"given": "James M."
},
"orcid": "0000-0002-3882-4414"
},
{
"name": {
"family": "Moriyama",
"given": "Kotaro"
},
"orcid": "0000-0003-1364-3761"
},
{
"name": {
"family": "Moscibrodzka",
"given": "Monika"
},
"orcid": "0000-0002-4661-6332"
},
{
"name": {
"family": "M\u00fcller",
"given": "Cornelia"
},
"orcid": "0000-0002-2739-2994"
},
{
"name": {
"family": "Mus",
"given": "Alejandro"
},
"orcid": "0000-0003-0329-6874"
},
{
"name": {
"family": "Musoke",
"given": "Gibwa"
},
"orcid": "0000-0003-1984-189X"
},
{
"name": {
"family": "Myserlis",
"given": "Ioannis"
},
"orcid": "0000-0003-3025-9497"
},
{
"name": {
"family": "Nadolski",
"given": "Andrew"
},
"orcid": "0000-0001-9479-9957"
},
{
"name": {
"family": "Nagai",
"given": "Hiroshi"
},
"orcid": "0000-0003-0292-3645"
},
{
"name": {
"family": "Nagar",
"given": "Neil M."
},
"orcid": "0000-0001-6920-662X"
},
{
"name": {
"family": "Nakamura",
"given": "Masanori"
},
"orcid": "0000-0001-6081-2420"
},
{
"name": {
"family": "Narayan",
"given": "Ramesh"
},
"orcid": "0000-0002-1919-2730"
},
{
"name": {
"family": "Narayanan",
"given": "Gopal"
},
"orcid": "0000-0002-4723-6569"
},
{
"name": {
"family": "Natarajan",
"given": "Iniyan"
},
"orcid": "0000-0001-8242-4373"
},
{
"name": {
"family": "Nathanail",
"given": "Antonios"
}
},
{
"name": {
"family": "Fuentes",
"given": "Santiago Navarro"
}
},
{
"name": {
"family": "Neilsen",
"given": "Joey"
},
"orcid": "0000-0002-8247-786X"
},
{
"name": {
"family": "Neri",
"given": "Roberto"
},
"orcid": "0000-0002-7176-4046"
},
{
"name": {
"family": "Ni",
"given": "Chunchong"
},
"orcid": "0000-0003-1361-5699"
},
{
"name": {
"family": "Noutsos",
"given": "Aristeidis"
},
"orcid": "0000-0002-4151-3860"
},
{
"name": {
"family": "Nowak",
"given": "Michael A."
},
"orcid": "0000-0001-6923-1315"
},
{
"name": {
"family": "Oh",
"given": "Junghwan"
},
"orcid": "0000-0002-4991-9638"
},
{
"name": {
"family": "Okino",
"given": "Hiroki"
},
"orcid": "0000-0003-3779-2016"
},
{
"name": {
"family": "Olivares",
"given": "H\u00e9ctor"
},
"orcid": "0000-0001-6833-7580"
},
{
"name": {
"family": "Ortiz-Le\u00f3n",
"given": "Gisela N."
},
"orcid": "0000-0002-2863-676X"
},
{
"name": {
"family": "Oyama",
"given": "Tomoaki"
},
"orcid": "0000-0003-4046-2923"
},
{
"name": {
"family": "\u00d6zel",
"given": "Feryal"
},
"orcid": "0000-0003-4413-1523"
},
{
"name": {
"family": "Palumbo",
"given": "Daniel C. M."
},
"orcid": "0000-0002-7179-3816"
},
{
"name": {
"family": "Paraschos",
"given": "Georgios Filippos"
},
"orcid": "0000-0001-6757-3098"
},
{
"name": {
"family": "Park",
"given": "Jongho"
},
"orcid": "0000-0001-6558-9053"
},
{
"name": {
"family": "Parsons",
"given": "Harriet"
},
"orcid": "0000-0002-6327-3423"
},
{
"name": {
"family": "Patel",
"given": "Nimesh"
},
"orcid": "0000-0002-6021-9421"
},
{
"name": {
"family": "Pen",
"given": "Ue-Li"
},
"orcid": "0000-0003-2155-9578"
},
{
"name": {
"family": "Pesce",
"given": "Dominic W."
},
"orcid": "0000-0002-5278-9221"
},
{
"name": {
"family": "Pi\u00e9tu",
"given": "Vincent"
}
},
{
"name": {
"family": "Plambeck",
"given": "Richard"
},
"orcid": "0000-0001-6765-9609"
},
{
"name": {
"family": "PopStefanija",
"given": "Aleksandar"
}
},
{
"name": {
"family": "Porth",
"given": "Oliver"
},
"orcid": "0000-0002-4584-2557"
},
{
"name": {
"family": "P\u00f6tzl",
"given": "Felix M."
},
"orcid": "0000-0002-6579-8311"
},
{
"name": {
"family": "Prather",
"given": "Ben"
},
"orcid": "0000-0002-0393-7734"
},
{
"name": {
"family": "Preciado-L\u00f3pez",
"given": "Jorge A."
},
"orcid": "0000-0002-4146-0113"
},
{
"name": {
"family": "Psaltis",
"given": "Dimitrios"
},
"orcid": "0000-0003-1035-3240"
},
{
"name": {
"family": "Pu",
"given": "Hung-Yi"
},
"orcid": "0000-0001-9270-8812"
},
{
"name": {
"family": "Ramakrishnan",
"given": "Venkatessh"
},
"orcid": "0000-0002-9248-086X"
},
{
"name": {
"family": "Rao",
"given": "Ramprasad"
},
"orcid": "0000-0002-1407-7944"
},
{
"name": {
"family": "Rawlings",
"given": "Mark G."
},
"orcid": "0000-0002-6529-202X"
},
{
"name": {
"family": "Raymond",
"given": "Alexander W."
},
"orcid": "0000-0002-5779-4767"
},
{
"name": {
"family": "Rezzolla",
"given": "Luciano"
},
"orcid": "0000-0002-1330-7103"
},
{
"name": {
"family": "Ricarte",
"given": "Angelo"
},
"orcid": "0000-0001-5287-0452"
},
{
"name": {
"family": "Ripperda",
"given": "Bart"
},
"orcid": "0000-0002-7301-3908"
},
{
"name": {
"family": "Roelofs",
"given": "Freek"
},
"orcid": "0000-0001-5461-3687"
},
{
"name": {
"family": "Rogers",
"given": "Alan"
},
"orcid": "0000-0003-1941-7458"
},
{
"name": {
"family": "Ros",
"given": "Eduardo"
},
"orcid": "0000-0001-9503-4892"
},
{
"name": {
"family": "Romero-Ca\u00f1izales",
"given": "Cristina"
},
"orcid": "0000-0001-6301-9073"
},
{
"name": {
"family": "Roshanineshat",
"given": "Arash"
},
"orcid": "0000-0002-8280-9238"
},
{
"name": {
"family": "Rottmann",
"given": "Helge"
},
"orcid": "0000-0003-1799-8228"
},
{
"name": {
"family": "Roy",
"given": "Alan L."
},
"orcid": "0000-0002-1931-0135"
},
{
"name": {
"family": "Ruiz",
"given": "Ignacio"
},
"orcid": "0000-0002-0965-5463"
},
{
"name": {
"family": "Ruszczyk",
"given": "Chet"
},
"orcid": "0000-0001-7278-9707"
},
{
"name": {
"family": "Rygl",
"given": "Kazi L. J."
},
"orcid": "0000-0003-4146-9043"
},
{
"name": {
"family": "S\u00e1nchez",
"given": "Salvador"
},
"orcid": "0000-0002-8042-5951"
},
{
"name": {
"family": "S\u00e1nchez-Arg\u00fcelles",
"given": "David"
},
"orcid": "0000-0002-7344-9920"
},
{
"name": {
"family": "S\u00e1nchez-Portal",
"given": "Miguel"
},
"orcid": "0000-0003-0981-9664"
},
{
"name": {
"family": "Sasada",
"given": "Mahito"
},
"orcid": "0000-0001-5946-9960"
},
{
"name": {
"family": "Satapathy",
"given": "Kaushik"
},
"orcid": "0000-0003-0433-3585"
},
{
"name": {
"family": "Savolainen",
"given": "Tuomas"
},
"orcid": "0000-0001-6214-1085"
},
{
"name": {
"family": "Schloerb",
"given": "F. Peter"
}
},
{
"name": {
"family": "Schonfeld",
"given": "Jonathan"
},
"orcid": "0000-0002-8909-2401"
},
{
"name": {
"family": "Schuster",
"given": "Karl-Friedrich"
},
"orcid": "0000-0003-2890-9454"
},
{
"name": {
"family": "Shao",
"given": "Lijing"
},
"orcid": "0000-0002-1334-8853"
},
{
"name": {
"family": "Shen",
"given": "Zhiqiang"
},
"orcid": "0000-0003-3540-8746"
},
{
"name": {
"family": "Small",
"given": "Des"
},
"orcid": "0000-0003-3723-5404"
},
{
"name": {
"family": "Sohn",
"given": "Bong Won"
},
"orcid": "0000-0002-4148-8378"
},
{
"name": {
"family": "SooHoo",
"given": "Jason"
},
"orcid": "0000-0003-1938-0720"
},
{
"name": {
"family": "Souccar",
"given": "Kamal"
},
"orcid": "0000-0001-7915-5272"
},
{
"id": "Sun-He",
"name": {
"family": "Sun",
"given": "He"
},
"orcid": "0000-0003-1526-6787"
},
{
"name": {
"family": "Tazaki",
"given": "Fumie"
},
"orcid": "0000-0003-0236-0600"
},
{
"name": {
"family": "Tetarenko",
"given": "Alexandra J."
},
"orcid": "0000-0003-3906-4354"
},
{
"name": {
"family": "Tiede",
"given": "Paul"
},
"orcid": "0000-0003-3826-5648"
},
{
"name": {
"family": "Tilanus",
"given": "Remo P. J."
},
"orcid": "0000-0002-6514-553X"
},
{
"name": {
"family": "Titus",
"given": "Michael"
},
"orcid": "0000-0001-9001-3275"
},
{
"name": {
"family": "Torne",
"given": "Pablo"
},
"orcid": "0000-0001-8700-6058"
},
{
"name": {
"family": "Traianou",
"given": "Efthalia"
},
"orcid": "0000-0002-1209-6500"
},
{
"name": {
"family": "Trent",
"given": "Tyler"
}
},
{
"name": {
"family": "Trippe",
"given": "Sascha"
},
"orcid": "0000-0003-0465-1559"
},
{
"name": {
"family": "Turk",
"given": "Matthew"
},
"orcid": "0000-0002-5294-0198"
},
{
"name": {
"family": "van Bemmel",
"given": "Ilse"
},
"orcid": "0000-0001-5473-2950"
},
{
"name": {
"family": "van Langevelde",
"given": "Huib Jan"
},
"orcid": "0000-0002-0230-5946"
},
{
"name": {
"family": "van Rossum",
"given": "Daniel R."
},
"orcid": "0000-0001-7772-6131"
},
{
"name": {
"family": "Vos",
"given": "Jesse"
},
"orcid": "0000-0003-3349-7394"
},
{
"name": {
"family": "Wagner",
"given": "Jan"
},
"orcid": "0000-0003-1105-6109"
},
{
"name": {
"family": "Ward-Thompson",
"given": "Derek"
},
"orcid": "0000-0003-1140-2761"
},
{
"name": {
"family": "Wardle",
"given": "John"
},
"orcid": "0000-0002-8960-2942"
},
{
"name": {
"family": "Weintroub",
"given": "Jonathan"
},
"orcid": "0000-0002-4603-5204"
},
{
"name": {
"family": "Wex",
"given": "Norbert"
},
"orcid": "0000-0003-4058-2837"
},
{
"name": {
"family": "Wharton",
"given": "Robert"
},
"orcid": "0000-0002-7416-5209"
},
{
"name": {
"family": "Wielgus",
"given": "Maciek"
},
"orcid": "0000-0002-8635-4242"
},
{
"name": {
"family": "Wiik",
"given": "Kaj"
},
"orcid": "0000-0002-0862-3398"
},
{
"name": {
"family": "Witzel",
"given": "Gunther"
},
"orcid": "0000-0003-2618-797X"
},
{
"name": {
"family": "Wondrak",
"given": "Michael F."
},
"orcid": "0000-0002-6894-1072"
},
{
"name": {
"family": "Wong",
"given": "George N."
},
"orcid": "0000-0001-6952-2147"
},
{
"name": {
"family": "Wu",
"given": "Qingwen"
},
"orcid": "0000-0003-4773-4987"
},
{
"name": {
"family": "Yamaguchi",
"given": "Paul"
},
"orcid": "0000-0002-6017-8199"
},
{
"name": {
"family": "Yoon",
"given": "Doosoo"
},
"orcid": "0000-0001-8694-8166"
},
{
"name": {
"family": "Young",
"given": "Andr\u00e9"
},
"orcid": "0000-0003-0000-2682"
},
{
"name": {
"family": "Young",
"given": "Ken"
},
"orcid": "0000-0002-3666-4920"
},
{
"name": {
"family": "Younsi",
"given": "Ziri"
},
"orcid": "0000-0001-9283-1191"
},
{
"name": {
"family": "Yuan",
"given": "Feng"
},
"orcid": "0000-0003-3564-6437"
},
{
"name": {
"family": "Yuan",
"given": "Ye-Fei"
},
"orcid": "0000-0002-7330-4756"
},
{
"name": {
"family": "Zensus",
"given": "J. Anton"
},
"orcid": "0000-0001-7470-3321"
},
{
"name": {
"family": "Zhang",
"given": "Shuo"
},
"orcid": "0000-0002-2967-790X"
},
{
"name": {
"family": "Zhao",
"given": "Guang-Yao"
},
"orcid": "0000-0002-4417-1659"
},
{
"name": {
"family": "Zhao",
"given": "Shan-Shan"
},
"orcid": "0000-0002-9774-3606"
},
{
"name": {
"family": "Agurto",
"given": "Claudio"
}
},
{
"name": {
"family": "Allardi",
"given": "Alexander"
}
},
{
"name": {
"family": "Amestica",
"given": "Rodrigo"
}
},
{
"name": {
"family": "Araneda",
"given": "Juan Pablo"
}
},
{
"name": {
"family": "Arriagada",
"given": "Oriel"
}
},
{
"name": {
"family": "Berghuis",
"given": "Jennie L."
},
"orcid": "0000-0003-2287-158X"
},
{
"name": {
"family": "Bertarini",
"given": "Alessandra"
}
},
{
"name": {
"family": "Berthold",
"given": "Ryan"
}
},
{
"name": {
"family": "Blanchard",
"given": "Jay"
},
"orcid": "0000-0002-2756-395X"
},
{
"name": {
"family": "Brown",
"given": "Ken"
}
},
{
"name": {
"family": "C\u00e1rdenas",
"given": "Mauricio"
}
},
{
"name": {
"family": "Cantzler",
"given": "Michael"
}
},
{
"name": {
"family": "Caro",
"given": "Patricio"
}
},
{
"name": {
"family": "Castillo-Dom\u00ednguez",
"given": "Edgar"
}
},
{
"name": {
"family": "Chan",
"given": "Tin Lok"
},
"orcid": "0000-0001-9197-932X"
},
{
"name": {
"family": "Chang",
"given": "Chih-Cheng"
}
},
{
"name": {
"family": "Chang",
"given": "Dominic O."
}
},
{
"name": {
"family": "Chang",
"given": "Shu-Hao"
}
},
{
"name": {
"family": "Chang",
"given": "Song-Chu"
}
},
{
"name": {
"family": "Chen",
"given": "Chung-Chen"
}
},
{
"name": {
"family": "Chilson",
"given": "Ryan"
}
},
{
"name": {
"family": "Chuter",
"given": "Tim C."
}
},
{
"name": {
"family": "Ciechanowicz",
"given": "Miroslaw"
}
},
{
"name": {
"family": "Colin-Beltran",
"given": "Edgar"
}
},
{
"name": {
"family": "Coulson",
"given": "Iain M."
},
"orcid": "0000-0002-7316-4626"
},
{
"name": {
"family": "Crowley",
"given": "Joseph"
}
},
{
"name": {
"family": "Degenaar",
"given": "Nathalie"
},
"orcid": "0000-0002-0092-3548"
},
{
"name": {
"family": "Dornbusch",
"given": "Sven"
}
},
{
"name": {
"family": "Dur\u00e1n",
"given": "Carlos A."
},
"orcid": "0000-0001-7622-3890"
},
{
"name": {
"family": "Everett",
"given": "Wendeline B."
},
"orcid": "0000-0002-5370-6651"
},
{
"name": {
"family": "Faber",
"given": "Aaron"
}
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"name": {
"family": "Fuchs",
"given": "Miriam M."
}
},
{
"name": {
"family": "Gale",
"given": "David M."
}
},
{
"name": {
"family": "Geertsema",
"given": "Gertie"
}
},
{
"name": {
"family": "Gonz\u00e1lez",
"given": "Edouard"
}
},
{
"name": {
"family": "Graham",
"given": "Dave"
}
},
{
"name": {
"family": "Gueth",
"given": "Fr\u00e9d\u00e9ric"
}
},
{
"name": {
"family": "Halverson",
"given": "Nils W."
},
"orcid": "0000-0003-2606-9340"
},
{
"name": {
"family": "Han",
"given": "Chih-Chiang"
}
},
{
"name": {
"family": "Han",
"given": "Kuo-Chang"
}
},
{
"name": {
"family": "Hasegawa",
"given": "Yutaka"
}
},
{
"name": {
"family": "Hern\u00e1ndez-Rebollar",
"given": "Jos\u00e9 Luis"
}
},
{
"name": {
"family": "Herrera",
"given": "Cristian"
}
},
{
"name": {
"family": "Herrero-Illana",
"given": "Ruben"
},
"orcid": "0000-0002-7758-8717"
},
{
"name": {
"family": "Heyminck",
"given": "Stefan"
}
},
{
"name": {
"family": "Hirota",
"given": "Akihiko"
},
"orcid": "0000-0002-0465-5421"
},
{
"name": {
"family": "Hoge",
"given": "James"
}
},
{
"name": {
"family": "Hostler Schimpf",
"given": "Shelbi R."
}
},
{
"name": {
"family": "Howie",
"given": "Ryan E."
},
"orcid": "0000-0002-5451-3624"
},
{
"name": {
"family": "Huang",
"given": "Yau-De"
}
},
{
"name": {
"family": "Jiang",
"given": "Homin"
}
},
{
"name": {
"family": "Jinchi",
"given": "Hao"
}
},
{
"name": {
"family": "John",
"given": "David"
}
},
{
"name": {
"family": "Kimura",
"given": "Kimihiro"
}
},
{
"name": {
"family": "Klein",
"given": "Thomas"
}
},
{
"name": {
"family": "Kubo",
"given": "Derek"
}
},
{
"name": {
"family": "Kuroda",
"given": "John"
}
},
{
"name": {
"family": "Kwon",
"given": "Caleb"
},
"orcid": "0000-0001-9006-7345"
},
{
"name": {
"family": "Lacasse",
"given": "Richard"
}
},
{
"name": {
"family": "Laing",
"given": "Robert"
},
"orcid": "0000-0001-6786-3087"
},
{
"name": {
"family": "Leitch",
"given": "Erik M."
},
"orcid": "0000-0001-8553-9336"
},
{
"name": {
"family": "Li",
"given": "Chao-Te"
}
},
{
"name": {
"family": "Liu",
"given": "Ching-Tang"
}
},
{
"name": {
"family": "Liu",
"given": "Kuan-Yu"
}
},
{
"name": {
"family": "Lin",
"given": "Lupin C.-C."
},
"orcid": "0000-0003-4083-9567"
},
{
"name": {
"family": "Lu",
"given": "Li-Ming"
}
},
{
"name": {
"family": "Mac-Auliffe",
"given": "Felipe"
}
},
{
"name": {
"family": "Martin-Cocher",
"given": "Pierre"
}
},
{
"name": {
"family": "Matulonis",
"given": "Callie"
}
},
{
"name": {
"family": "Maute",
"given": "John K."
},
"orcid": "0000-0002-5744-4249"
},
{
"name": {
"family": "Messias",
"given": "Hugo"
},
"orcid": "0000-0002-2985-7994"
},
{
"name": {
"family": "Meyer-Zhao",
"given": "Zheng"
}
},
{
"name": {
"family": "Monta\u00f1a",
"given": "Alfredo"
}
},
{
"name": {
"family": "Montenegro-Montes",
"given": "Francisco"
},
"orcid": "0000-0002-7430-3771"
},
{
"name": {
"family": "Montgomerie",
"given": "William"
}
},
{
"name": {
"family": "Moreno Nolasco",
"given": "Marcos Emir"
}
},
{
"name": {
"family": "Muders",
"given": "Dirk"
},
"orcid": "0000-0002-2315-2571"
},
{
"name": {
"family": "Nishioka",
"given": "Hiroaki"
}
},
{
"name": {
"family": "Norton",
"given": "Timothy J."
}
},
{
"name": {
"family": "Nystrom",
"given": "George"
}
},
{
"name": {
"family": "Ogawa",
"given": "Hideo"
}
},
{
"name": {
"family": "Olivares",
"given": "Rodrigo"
}
},
{
"name": {
"family": "Oshiro",
"given": "Peter"
}
},
{
"name": {
"family": "P\u00e9rez-Beaupuits",
"given": "Juan Pablo"
},
"orcid": "0000-0003-3536-2274"
},
{
"name": {
"family": "Parra",
"given": "Rodrigo"
}
},
{
"name": {
"family": "Phillips",
"given": "Neil M."
}
},
{
"name": {
"family": "Poirier",
"given": "Michael"
},
"orcid": "0000-0001-6641-0959"
},
{
"name": {
"family": "Pradel",
"given": "Nicolas"
}
},
{
"name": {
"family": "Qiu",
"given": "Richard"
},
"orcid": "0000-0003-3462-0817"
},
{
"name": {
"family": "Raffin",
"given": "Philippe A."
}
},
{
"name": {
"family": "Rahlin",
"given": "Alexandra S."
},
"orcid": "0000-0003-3953-1776"
},
{
"name": {
"family": "Ram\u00edrez",
"given": "Jorge"
}
},
{
"name": {
"family": "Ressler",
"given": "Sean"
},
"orcid": "0000-0003-0220-5723"
},
{
"name": {
"family": "Reynolds",
"given": "Mark"
},
"orcid": "0000-0003-1621-9392"
},
{
"name": {
"family": "Rodr\u00edguez-Montoya",
"given": "Iv\u00e1n"
}
},
{
"name": {
"family": "Saez-Madain",
"given": "Alejandro F."
},
"orcid": "0000-0002-0804-3414"
},
{
"name": {
"family": "Santana",
"given": "Jorge"
}
},
{
"name": {
"family": "Shaw",
"given": "Paul"
}
},
{
"name": {
"family": "Shirkey",
"given": "Leslie E."
}
},
{
"name": {
"family": "Silva",
"given": "Kevin M."
}
},
{
"name": {
"family": "Snow",
"given": "William"
}
},
{
"name": {
"family": "Sousa",
"given": "Don"
},
"orcid": "0000-0002-2625-2607"
},
{
"name": {
"family": "Sridharan",
"given": "T. K."
}
},
{
"name": {
"family": "Stahm",
"given": "William"
}
},
{
"name": {
"family": "Stark",
"given": "Anthony A."
},
"orcid": "0000-0002-2718-9996"
},
{
"name": {
"family": "Test",
"given": "John"
}
},
{
"name": {
"family": "Torstensson",
"given": "Karl"
}
},
{
"name": {
"family": "Venegas",
"given": "Paulina"
}
},
{
"name": {
"family": "Walther",
"given": "Craig"
}
},
{
"name": {
"family": "Wei",
"given": "Ta-Shun"
}
},
{
"name": {
"family": "White",
"given": "Chris"
},
"orcid": "0000-0001-7448-4253"
},
{
"name": {
"family": "Wieching",
"given": "Gundolf"
}
},
{
"name": {
"family": "Wijnands",
"given": "Rudy"
},
"orcid": "0000-0002-3516-2152"
},
{
"name": {
"family": "Wouterloot",
"given": "Jan G. A."
},
"orcid": "0000-0002-4694-6905"
},
{
"name": {
"family": "Yu",
"given": "Chen-Yu"
}
},
{
"name": {
"family": "Yu",
"given": "Wei"
},
"orcid": "0000-0002-5168-6052"
},
{
"name": {
"family": "Zeballos",
"given": "Milagros"
}
}
]
},
"title": "First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Black holes; Kerr black holes; Rotating black holes; Heterodyne interferometry; Galactic center; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 February 5; revised 2022 March 25; accepted 2022 March 25; published 2022 May 12. \n\nWe thank the anonymous referees for helpful comments that improved the paper. \n\nThe Event Horizon Telescope Collaboration thanks the following organizations and programs: the Academia Sinica; the Academy of Finland (projects 274477, 284495, 312496, 315721); the Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID), Chile via NCN19_058 (TITANs) and Fondecyt 1221421, the Alexander von Humboldt Stiftung; an Alfred P. Sloan Research Fellowship; Allegro, the European ALMA Regional Centre node in the Netherlands, the NL astronomy research network NOVA and the astronomy institutes of the University of Amsterdam, Leiden University and Radboud University; the ALMA North America Development Fund; the Black Hole Initiative, which is funded by grants from the John Templeton Foundation and the Gordon and Betty Moore Foundation (although the opinions expressed in this work are those of the author(s) and do not necessarily reflect the views of these Foundations); Chandra DD7-18089X and TM6-17006X; the China Scholarship Council; China Postdoctoral Science Foundation fellowship (2020M671266); Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT, Mexico, projects U0004-246083, U0004-259839, F0003-272050, M0037-279006, F0003-281692, 104497, 275201, 263356); the Consejer\u00eda de Econom\u00eda, Conocimiento, Empresas y Universidad of the Junta de Andaluc\u00eda (grant P18-FR-1769), the Consejo Superior de Investigaciones Cient\u00edficas (grant 2019AEP112); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Direcci\u00f3n General de Asuntos del Personal Acad\u00e9mico-Universidad Nacional Aut\u00f3noma de M\u00e9xico (DGAPA-UNAM, projects IN112417 and IN112820); the Dutch Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and grant OCENW.KLEIN.113; the Dutch National Supercomputers, Cartesius and Snellius (NWO Grant 2021.013); the EACOA Fellowship awarded by the East Asia Core Observatories Association, which consists of the Academia Sinica Institute of Astronomy and Astrophysics, the National Astronomical Observatory of Japan, Center for Astronomical Mega-Science, Chinese Academy of Sciences, and the Korea Astronomy and Space Science Institute; the European Research Council (ERC) Synergy Grant \"BlackHoleCam: Imaging the Event Horizon of Black Holes\" (grant 610058); the European Union Horizon 2020 research and innovation programme under grant agreements RadioNet (No 730562) and M2FINDERS (No 101018682); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177 and GenT Program (project CIDEGENT/2018/021); MICINN Research Project PID2019-108995GB-C22; the European Research Council for advanced grant \"JETSET: Launching, propagation and emission of relativistic jets from binary mergers and across mass scales\" (Grant No. 884631); the Institute for Advanced Study; the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; DFG research grant \"Jet physics on horizon scales and beyond\" (Grant No. FR 4069/2-1); Joint Princeton/Flatiron and Joint Columbia/Flatiron Postdoctoral Fellowships, research at the Flatiron Institute is supported by the Simons Foundation; the Japan Ministry of Education, Culture, Sports, Science and Technology (MEXT; grant JPMXP1020200109); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); the Joint Institute for Computational Fundamental Science, Japan; the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSW-SLH057, QYZDJSSW-SYS008, ZDBS-LY-SLH011); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP21H01137, JP18H03721, JP18K13594, 18K03709, JP19K14761, 18H01245, 25120007); the Malaysian Fundamental Research Grant Scheme (FRGS) FRGS/1/2019/STG02/UM/02/6; the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (103-2119-M-001-010-MY2, 105-2112-M-001-025-MY3, 105-2119-M-001-042, 106-2112-M-001-011, 106-2119-M-001-013, 106-2119-M-001-027, 106-2923-M-001-005, 107-2119-M-001-017, 107-2119-M-001-020, 107-2119-M-001-041, 107-2119-M-110-005, 107-2923-M-001-009, 108-2112-M-001-048, 108-2112-M-001-051, 108-2923-M-001-002, 109-2112-M-001-025, 109-2124-M-001-005, 109-2923-M-001-001, 110-2112-M-003-007-MY2, 110-2112-M-001-033, 110-2124-M-001-007, and 110-2923-M-001-001); the Ministry of Education (MoE) of Taiwan Yushan Young Scholar Program; the Physics Division, National Center for Theoretical Sciences of Taiwan; the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC20K1567, NASA Astrophysics Theory Program grant 80NSSC20K0527, NASA NuSTAR award 80NSSC20K0645); NASA Hubble Fellowship grant HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555; the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2017YFA0402703, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1440254, AST-1555365, AST-1614868, AST-1615796, AST-1715061, AST-1716327, AST-1716536, OISE-1743747, AST-1816420, AST-1935980, AST-2034306); NSF Astronomy and Astrophysics Postdoctoral Fellowship (AST-1903847); the Natural Science Foundation of China (grants 11650110427, 10625314, 11721303, 11725312, 11873028, 11933007, 11991052, 11991053, 12192220, 12192223); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, the Korea Research Fellowship Program: NRF-2015H1D3A1066561, Brain Pool Program: 2019H1D3A1A01102564, Basic Research Support Grant 2019R1F1A1059721, 2021R1A6A3A01086420, 2022R1C1C1005255); Netherlands Research School for Astronomy (NOVA) Virtual Institute of Accretion (VIA) postdoctoral fellowships; Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648); the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Spanish Ministerio de Ciencia e Innovaci\u00f3n (grants PGC2018-098915-B-C21, AYA2016-80889-P, PID2019-108995GB-C21, PID2020-117404GB-C21); the University of Pretoria for financial aid in the provision of the new Cluster Server nodes and SuperMicro (USA) for a SEEDING GRANT approved towards these nodes in 2020; the Shanghai Pilot Program for Basic Research, Chinese Academy of Science, Shanghai Branch (JCYJ-SHFY-2021-013); the State Agency for Research of the Spanish MCIU through the \"Center of Excellence Severo Ochoa\" award for the Instituto de Astrof\u00edsica de Andaluc\u00eda (SEV-2017- 0709); the Spinoza Prize SPI 78-409; the South African Research Chairs Initiative, through the South African Radio Astronomy Observatory (SARAO, grant ID 77948), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Innovation (DSI) of South Africa; the Toray Science Foundation; Swedish Research Council (VR); the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001); and the YCAA Prize Postdoctoral Fellowship. \n\nWe thank the staff at the participating observatories, correlation centers, and institutions for their enthusiastic support. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2016.1.01154.V. ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), NSF, and National Institutes of Natural Sciences of Japan, together with National Research Council (Canada), Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities, Inc. (AUI)/NRAO, and the National Astronomical Observatory of Japan (NAOJ). The NRAO is a facility of the NSF operated under cooperative agreement by AUI. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. We also thank the Center for Computational Astrophysics, National Astronomical Observatory of Japan. The computing cluster of Shanghai VLBI correlator supported by the Special Fund for Astronomy from the Ministry of Finance in China is acknowledged. \n\nAPEX is a collaboration between the Max-Planck-Institut f\u00fcr Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key Research and Development Program (No. 2017YFA0402700) of China and Natural Science Foundation of China grant 11873028. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. The LMT is a project operated by the Instituto Nacional de Astr\u00f3fisica, \u00d3ptica, y Electr\u00f3nica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30-m telescope on Pico Veleta, Spain is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany) and IGN (Instituto Geogr\u00e1fico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. Support for SPT participation in the EHT is provided by the National Science Foundation through award OPP-1852617 to the University of Chicago. Partial support is also provided by the Kavli Institute of Cosmological Physics at the University of Chicago. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA. \n\nThis work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI-1743442. XSEDE Stampede2 resource at TACC was allocated through TG-AST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. This research is part of the Frontera computing project at the Texas Advanced Computing Center through the Frontera Large-Scale Community Partnerships allocation AST20023. Frontera is made possible by National Science Foundation award OAC-1818253. This research was carried out using resources provided by the Open Science Grid, which is supported by the National Science Foundation and the U.S. Department of Energy Office of Science. Additional work used ABACUS2.0, which is part of the eScience center at Southern Denmark University. Simulations were also performed on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, on the HazelHen cluster at the HLRS in Stuttgart, and on the Pi2.0 and Siyuan Mark-I at Shanghai Jiao Tong University. The computer resources of the Finnish IT Center for Science (CSC) and the Finnish Computing Competence Infrastructure (FCCI) project are acknowledged. This research was enabled in part by support provided by Compute Ontario (http://computeontario.ca), Calcul Quebec (http://www.calculquebec.ca) and Compute Canada (http://www.computecanada.ca). \n\nThe EHTC has received generous donations of FPGA chips from Xilinx Inc., under the Xilinx University Program. The EHTC has benefited from technology shared under open-source license by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). The EHT project is grateful to T4Science and Microsemi for their assistance with Hydrogen Masers. This research has made use of NASA's Astrophysics Data System. We gratefully acknowledge the support provided by the extended staff of the ALMA, both from the inception of the ALMA Phasing Project through the observational campaigns of 2017 and 2018. We would like to thank A. Deller and W. Brisken for EHT-specific support with the use of DiFX. We thank Martin Shepherd for the addition of extra features in the Difmap software that were used for the CLEAN imaging results presented in this paper. We acknowledge the significance that Maunakea, where the SMA and JCMT EHT stations are located, has for the indigenous Hawaiian people. \n\nFacilities: EHT - , ALMA - , APEX - , IRAM:30 m - , JCMT - , LMT - , SMA - , ARO:SMT - , SPT - , Chandra - , EAVN - , GMVA - , NuSTAR - , Swift - , VLT. -\n\nPublished - Akiyama_2022_ApJL_930_L12.pdf
",
"abstract": "We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A*), the Galactic center source associated with a supermassive black hole. These observations were conducted in 2017 using a global interferometric array of eight telescopes operating at a wavelength of \u03bb = 1.3 mm. The EHT data resolve a compact emission region with intrahour variability. A variety of imaging and modeling analyses all support an image that is dominated by a bright, thick ring with a diameter of 51.8 \u00b1 2.3 \u03bcas (68% credible interval). The ring has modest azimuthal brightness asymmetry and a comparatively dim interior. Using a large suite of numerical simulations, we demonstrate that the EHT images of Sgr A* are consistent with the expected appearance of a Kerr black hole with mass \u223c4 \u00d7 10\u2076 M_\u2299, which is inferred to exist at this location based on previous infrared observations of individual stellar orbits, as well as maser proper-motion studies. Our model comparisons disfavor scenarios where the black hole is viewed at high inclination (i > 50\u00b0), as well as nonspinning black holes and those with retrograde accretion disks. Our results provide direct evidence for the presence of a supermassive black hole at the center of the Milky Way, and for the first time we connect the predictions from dynamical measurements of stellar orbits on scales of 10\u00b3\u201310\u2075 gravitational radii to event-horizon-scale images and variability. Furthermore, a comparison with the EHT results for the supermassive black hole M87* shows consistency with the predictions of general relativity spanning over three orders of magnitude in central mass.",
"date": "2022-05-10",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "930",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L12",
"id_number": "CaltechAUTHORS:20220513-733955000",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220513-733955000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Academia Sinica"
},
{
"agency": "Academy of Finland",
"grant_number": "274477"
},
{
"agency": "Academy of Finland",
"grant_number": "284495"
},
{
"agency": "Academy of Finland",
"grant_number": "312496"
},
{
"agency": "Academy of Finland",
"grant_number": "315721"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1221421"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Alfred P. Sloan Research Fellowship"
},
{
"agency": "Allegro"
},
{
"agency": "ALMA Regional Centre"
},
{
"agency": "Nederlandse Onderzoekschool Voor Astronomie (NOVA)"
},
{
"agency": "University of Amsterdam"
},
{
"agency": "Leiden University"
},
{
"agency": "Radboud University"
},
{
"agency": "ALMA North America Development Fund"
},
{
"agency": "Black Hole Initiative"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Gordon and Betty Moore Foundation"
},
{
"agency": "NASA Chandra",
"grant_number": "DD7-18089X"
},
{
"agency": "NASA Chandra",
"grant_number": "TM6-17006X"
},
{
"agency": "China Scholarship Council"
},
{
"agency": "China Postdoctoral Science Foundation",
"grant_number": "2020M671266"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "U0004-246083"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "U0004-259839"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "F0003-272050"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "M0037-279006"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "F0003-281692"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "104497"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "275201"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "263356"
},
{
"agency": "Junta de Andaluc\u00eda",
"grant_number": "P18-FR-1769"
},
{
"agency": "Consejo Superior de Investigaciones Cient\u00edficas",
"grant_number": "2019AEP112"
},
{
"agency": "Delaney Family John A. Wheeler Chair"
},
{
"agency": "Perimeter Institute for Theoretical Physics"
},
{
"agency": "Direcci\u00f3n General de Asuntos del Personal Acad\u00e9mico-Universidad Nacional Aut\u00f3noma de M\u00e9xico",
"grant_number": "IN112417"
},
{
"agency": "Direcci\u00f3n General de Asuntos del Personal Acad\u00e9mico-Universidad Nacional Aut\u00f3noma de M\u00e9xico",
"grant_number": "IN112820"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "639.043.513"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "OCENW.KLEIN.113"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "2021.013"
},
{
"agency": "East Asia Core Observatories Association"
},
{
"agency": "Academia Sinica Institute of Astronomy and Astrophysics (ASIAA)"
},
{
"agency": "National Astronomical Observatory of Japan"
},
{
"agency": "Center for Astronomical Mega-Science"
},
{
"agency": "Korea Astronomy and Space Science Institute (KASI)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "610058"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "730562"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101018682"
},
{
"agency": "Generalitat Valenciana",
"grant_number": "APOSTD/2018/177"
},
{
"agency": "Generalitat Valenciana",
"grant_number": "CIDEGENT/2018/021"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCINN)",
"grant_number": "PID2019-108995GB-C22"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "884631"
},
{
"agency": "Institute for Advanced Study"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "International Max Planck Research School for Astronomy and Astrophysics"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "FR 4069/2-1"
},
{
"agency": "Princeton University"
},
{
"agency": "Flatiron Institute"
},
{
"agency": "Columbia University"
},
{
"agency": "Simons Foundation"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "JPMXP1020200109"
},
{
"agency": "Monbukagakusho"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP17J08829"
},
{
"agency": "Joint Institute for Computational Fundamental Science"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "QYZDJ-SSW-SLH057"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "QYZDJSSW-SYS008"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "ZDBS-LY-SLH011"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Max-Planck-Gesellschaft"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18KK0090"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP21H01137"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP18H03721"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP18K13594"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18K03709"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP19K14761"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18H01245"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "25120007"
},
{
"agency": "Malaysian Fundamental Research Grant",
"grant_number": "FRGS/1/2019/STG02/UM/02/6"
},
{
"agency": "Massachusetts Institute of Technology (MIT)"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "103-2119-M-001-010-MY2"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "105-2112-M-001-025-MY3"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "105-2119-M-001-042"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2112-M-001-011"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2119-M-001-013"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2119-M-001-027"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2923-M-001-005"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-001-017"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-001-020"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-001-041"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-110-005"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2923-M-001-009"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "108-2112-M-001-048"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "108-2112-M-001-051"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "108-2923-M-001-002"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "109-2112-M-001-025"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "109-2124-M-001-005"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "109-2923-M-001-001"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2112-M-003-007-MY2"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2112-M-001-033"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2124-M-001-007"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2923-M-001-001"
},
{
"agency": "Ministry of Education (Taipei)"
},
{
"agency": "National Center for Theoretical Sciences (Taiwan)"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1567"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0527"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0645"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51431.001-A"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "National Institute of Natural Sciences (NINS)"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400704"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2017YFA0402703"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400702"
},
{
"agency": "NSF",
"grant_number": "AST-0096454"
},
{
"agency": "NSF",
"grant_number": "AST-0352953"
},
{
"agency": "NSF",
"grant_number": "AST-0521233"
},
{
"agency": "NSF",
"grant_number": "AST-0705062"
},
{
"agency": "NSF",
"grant_number": "AST-0905844"
},
{
"agency": "NSF",
"grant_number": "AST-0922984"
},
{
"agency": "NSF",
"grant_number": "AST-1126433"
},
{
"agency": "NSF",
"grant_number": "AST-1140030"
},
{
"agency": "NSF Graduate Research Fellowship",
"grant_number": "DGE-1144085"
},
{
"agency": "NSF",
"grant_number": "AST-1207704"
},
{
"agency": "NSF",
"grant_number": "AST-1207730"
},
{
"agency": "NSF",
"grant_number": "AST-1207752"
},
{
"agency": "NSF",
"grant_number": "MRI-1228509"
},
{
"agency": "NSF",
"grant_number": "OPP-1248097"
},
{
"agency": "NSF",
"grant_number": "AST-1310896"
},
{
"agency": "NSF",
"grant_number": "AST-1440254"
},
{
"agency": "NSF",
"grant_number": "AST-1555365"
},
{
"agency": "NSF",
"grant_number": "AST-1614868"
},
{
"agency": "NSF",
"grant_number": "AST-1615796"
},
{
"agency": "NSF",
"grant_number": "AST-1715061"
},
{
"agency": "NSF",
"grant_number": "AST-1716327"
},
{
"agency": "NSF",
"grant_number": "AST-1716536"
},
{
"agency": "NSF",
"grant_number": "OISE-1743747"
},
{
"agency": "NSF",
"grant_number": "AST-1816420"
},
{
"agency": "NSF",
"grant_number": "AST-1935980"
},
{
"agency": "NSF",
"grant_number": "AST-2034306"
},
{
"agency": "NSF Astronomy and Astrophysics Postdoctoral Fellowship",
"grant_number": "AST-1903847"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11650110427"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "10625314"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11721303"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11725312"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11873028"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11933007"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11991052"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11991053"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12192220"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12192223"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "National Youth Thousand Talents Program of China"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2015H1A2A1033752"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2015H1D3A1066561"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2019H1D3A1A01102564"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2019R1F1A1059721"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2021R1A6A3A01086420"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2022R1C1C1005255"
},
{
"agency": "Onsala Space Observatory (OSO)"
},
{
"agency": "Swedish Research Council",
"grant_number": "2017-00648"
},
{
"agency": "Department of Innovation, Science and Economic Development (Canada)"
},
{
"agency": "Province of Ontario Ministry of Research, Innovation and Science"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "PGC2018-098915-B-C21"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "AYA2016-80889-P"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "PID2019-108995GB-C21"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "PID2020-117404GB-C21"
},
{
"agency": "University of Pretoria"
},
{
"agency": "SuperMicro Corporation"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "JCYJ-SHFY-2021-013"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Spinoza Prize",
"grant_number": "SPI 78-409"
},
{
"agency": "South African Radio Astronomy Observatory (SARAO)",
"grant_number": "77948"
},
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "Department of Science and Innovation (South Africa)"
},
{
"agency": "Toray Science Foundation"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "89233218CNA000001"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC05-00OR22725"
},
{
"agency": "Ministry of Finance (China)"
},
{
"agency": "Smithsonian Institution"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2017YFA0402700"
},
{
"agency": "Natural Science Foundation of China",
"grant_number": "11873028"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Instituto Geogr\u00e1fico Nacional (IGN)"
},
{
"agency": "State of Arizona"
},
{
"agency": "NSF",
"grant_number": "OPP-1852617"
},
{
"agency": "Kavli Institute of Cosmological Physics"
},
{
"agency": "NSF",
"grant_number": "ACI-1548562"
},
{
"agency": "NSF",
"grant_number": "DBI-0735191"
},
{
"agency": "NSF",
"grant_number": "DBI-1265383"
},
{
"agency": "NSF",
"grant_number": "DBI-1743442"
},
{
"agency": "NSF",
"grant_number": "TG-AST170024"
},
{
"agency": "NSF",
"grant_number": "TG-AST080026N"
},
{
"agency": "NSF",
"grant_number": "AST-170028"
},
{
"agency": "NSF",
"grant_number": "AST-20023"
},
{
"agency": "NSF",
"grant_number": "OAC-1818253"
},
{
"agency": "Compute Ontario"
},
{
"agency": "Calcul Quebec"
},
{
"agency": "Compute Canada"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"corp_creators": {
"items": [
"Event Horizon Telescope Collaboration"
]
},
"doi": "10.3847/2041-8213/ac6674",
"primary_object": {
"basename": "Akiyama_2022_ApJL_930_L12.pdf",
"url": "https://authors.library.caltech.edu/records/9c3m1-t3d06/files/Akiyama_2022_ApJL_930_L12.pdf"
},
"pub_year": "2022",
"author_list": "Akiyama, Kazunori; Alberdi, Antxon; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z0dap-rsm30",
"eprint_id": 115750,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:34:56",
"lastmod": "2025-11-20 20:49:12",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Akiyama-Kazunori",
"name": {
"family": "Akiyama",
"given": "Kazunori"
},
"orcid": "0000-0002-9475-4254"
},
{
"name": {
"family": "Alberdi",
"given": "Antxon"
},
"orcid": "0000-0002-9371-1033"
},
{
"name": {
"family": "Alef",
"given": "Walter"
}
},
{
"name": {
"family": "Algaba",
"given": "Juan Carlos"
},
"orcid": "0000-0001-6993-1696"
},
{
"name": {
"family": "Anantua",
"given": "Richard"
},
"orcid": "0000-0003-3457-7660"
},
{
"name": {
"family": "Asada",
"given": "Keiichi"
},
"orcid": "0000-0001-6988-8763"
},
{
"name": {
"family": "Azulay",
"given": "Rebecca"
},
"orcid": "0000-0002-2200-5393"
},
{
"name": {
"family": "Bach",
"given": "Uwe"
},
"orcid": "0000-0002-7722-8412"
},
{
"name": {
"family": "Baczko",
"given": "Anne-Kathrin"
},
"orcid": "0000-0003-3090-3975"
},
{
"name": {
"family": "Ball",
"given": "David"
}
},
{
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"name": {
"family": "Barrett",
"given": "John"
},
"orcid": "0000-0002-9290-0764"
},
{
"name": {
"family": "Baub\u00f6ck",
"given": "Michi"
},
"orcid": "0000-0002-5518-2812"
},
{
"name": {
"family": "Benson",
"given": "Bradford A."
},
"orcid": "0000-0002-5108-6823"
},
{
"name": {
"family": "Bintley",
"given": "Dan"
}
},
{
"name": {
"family": "Blackburn",
"given": "Lindy"
},
"orcid": "0000-0002-9030-642X"
},
{
"name": {
"family": "Blundell",
"given": "Raymond"
},
"orcid": "0000-0002-5929-5857"
},
{
"id": "Bouman-K-L",
"name": {
"family": "Bouman",
"given": "Katherine L."
},
"orcid": "0000-0003-0077-4367"
},
{
"name": {
"family": "Bower",
"given": "Geoffrey C."
},
"orcid": "0000-0003-4056-9982"
},
{
"name": {
"family": "Boyce",
"given": "Hope"
},
"orcid": "0000-0002-6530-5783"
},
{
"name": {
"family": "Bremer",
"given": "Michael"
}
},
{
"name": {
"family": "Brinkerink",
"given": "Christiaan D."
},
"orcid": "0000-0002-2322-0749"
},
{
"name": {
"family": "Brissenden",
"given": "Roger"
},
"orcid": "0000-0002-2556-0894"
},
{
"name": {
"family": "Britzen",
"given": "Silke"
},
"orcid": "0000-0001-9240-6734"
},
{
"name": {
"family": "Broderick",
"given": "Avery E."
},
"orcid": "0000-0002-3351-760X"
},
{
"name": {
"family": "Broguiere",
"given": "Dominique"
},
"orcid": "0000-0001-9151-6683"
},
{
"name": {
"family": "Bronzwaer",
"given": "Thomas"
},
"orcid": "0000-0003-1151-3971"
},
{
"name": {
"family": "Bustamante",
"given": "Sandra"
},
"orcid": "0000-0001-6169-1894"
},
{
"name": {
"family": "Byun",
"given": "Do-Young"
},
"orcid": "0000-0003-1157-4109"
},
{
"name": {
"family": "Carlstrom",
"given": "John E."
},
"orcid": "0000-0002-2044-7665"
},
{
"name": {
"family": "Ceccobello",
"given": "Chiara"
},
"orcid": "0000-0002-4767-9925"
},
{
"name": {
"family": "Chael",
"given": "Andrew"
},
"orcid": "0000-0003-2966-6220"
},
{
"name": {
"family": "Chan",
"given": "Chi-kwan"
},
"orcid": "0000-0001-6337-6126"
},
{
"name": {
"family": "Chatterjee",
"given": "Koushik"
},
"orcid": "0000-0002-2825-3590"
},
{
"name": {
"family": "Chatterjee",
"given": "Shami"
},
"orcid": "0000-0002-2878-1502"
},
{
"name": {
"family": "Chen",
"given": "Ming-Tang"
},
"orcid": "0000-0001-6573-3318"
},
{
"name": {
"family": "Chen",
"given": "Yongjun"
},
"orcid": "0000-0001-5650-6770"
},
{
"name": {
"family": "Cheng",
"given": "Xiaopeng"
},
"orcid": "0000-0003-4407-9868"
},
{
"name": {
"family": "Cho",
"given": "Ilje"
},
"orcid": "0000-0001-6083-7521"
},
{
"name": {
"family": "Christian",
"given": "Pierre"
},
"orcid": "0000-0001-6820-9941"
},
{
"name": {
"family": "Conroy",
"given": "Nicholas S."
},
"orcid": "0000-0003-2886-2377"
},
{
"name": {
"family": "Conway",
"given": "John E."
},
"orcid": "0000-0003-2448-9181"
},
{
"name": {
"family": "Cordes",
"given": "James M."
},
"orcid": "0000-0002-4049-1882"
},
{
"name": {
"family": "Crawford",
"given": "Thomas M."
},
"orcid": "0000-0001-9000-5013"
},
{
"name": {
"family": "Crew",
"given": "Geoffrey B."
},
"orcid": "0000-0002-2079-3189"
},
{
"name": {
"family": "Cruz-Osorio",
"given": "Alejandro"
},
"orcid": "0000-0002-3945-6342"
},
{
"name": {
"family": "Cui",
"given": "Yuzhu"
},
"orcid": "0000-0001-6311-4345"
},
{
"name": {
"family": "Davelaar",
"given": "Jordy"
},
"orcid": "0000-0002-2685-2434"
},
{
"name": {
"family": "De Laurentis",
"given": "Mariafelicia"
},
"orcid": "0000-0002-9945-682X"
},
{
"name": {
"family": "Deane",
"given": "Roger"
},
"orcid": "0000-0003-1027-5043"
},
{
"name": {
"family": "Dempsey",
"given": "Jessica"
},
"orcid": "0000-0003-1269-9667"
},
{
"name": {
"family": "Desvignes",
"given": "Gregory"
},
"orcid": "0000-0003-3922-4055"
},
{
"name": {
"family": "Dexter",
"given": "Jason"
},
"orcid": "0000-0003-3903-0373"
},
{
"name": {
"family": "Dhruv",
"given": "Vedant"
},
"orcid": "0000-0001-6765-877X"
},
{
"name": {
"family": "Doeleman",
"given": "Sheperd S."
},
"orcid": "0000-0002-9031-0904"
},
{
"name": {
"family": "Dougal",
"given": "Sean"
},
"orcid": "0000-0002-3769-1314"
},
{
"name": {
"family": "Dzib",
"given": "Sergio A."
},
"orcid": "0000-0001-6010-6200"
},
{
"name": {
"family": "Eatough",
"given": "Ralph P."
},
"orcid": "0000-0001-6196-4135"
},
{
"name": {
"family": "Emami",
"given": "Razieh"
},
"orcid": "0000-0002-2791-5011"
},
{
"name": {
"family": "Falcke",
"given": "Heino"
},
"orcid": "0000-0002-2526-6724"
},
{
"name": {
"family": "Farah",
"given": "Joseph"
},
"orcid": "0000-0003-4914-5625"
},
{
"name": {
"family": "Fish",
"given": "Vincent L."
},
"orcid": "0000-0002-7128-9345"
},
{
"name": {
"family": "Fomalont",
"given": "Ed"
},
"orcid": "0000-0002-9036-2747"
},
{
"name": {
"family": "Ford",
"given": "H. Alyson"
},
"orcid": "0000-0002-9797-0972"
},
{
"name": {
"family": "Fraga-Encinas",
"given": "Raquel"
},
"orcid": "0000-0002-5222-1361"
},
{
"name": {
"family": "Freeman",
"given": "William T."
}
},
{
"name": {
"family": "Friberg",
"given": "Per"
},
"orcid": "0000-0002-8010-8454"
},
{
"name": {
"family": "Fromm",
"given": "Christian M."
},
"orcid": "0000-0002-1827-1656"
},
{
"name": {
"family": "Fuentes",
"given": "Antonio"
},
"orcid": "0000-0002-8773-4933"
},
{
"name": {
"family": "Galison",
"given": "Peter"
},
"orcid": "0000-0002-6429-3872"
},
{
"name": {
"family": "Gammie",
"given": "Charles F."
},
"orcid": "0000-0001-7451-8935"
},
{
"name": {
"family": "Garc\u00eda",
"given": "Roberto"
},
"orcid": "0000-0002-6584-7443"
},
{
"name": {
"family": "Gentaz",
"given": "Olivier"
},
"orcid": "0000-0002-0115-4605"
},
{
"name": {
"family": "Georgiev",
"given": "Boris"
},
"orcid": "0000-0002-3586-6424"
},
{
"name": {
"family": "Goddi",
"given": "Ciriaco"
},
"orcid": "0000-0002-2542-7743"
},
{
"name": {
"family": "Gold",
"given": "Roman"
},
"orcid": "0000-0003-2492-1966"
},
{
"name": {
"family": "G\u00f3mez-Ruiz",
"given": "Arturo I."
},
"orcid": "0000-0001-9395-1670"
},
{
"name": {
"family": "G\u00f3mez",
"given": "Jos\u00e9 L."
},
"orcid": "0000-0003-4190-7613"
},
{
"name": {
"family": "Gu",
"given": "Minfeng"
},
"orcid": "0000-0002-4455-6946"
},
{
"name": {
"family": "Gurwell",
"given": "Mark"
},
"orcid": "0000-0003-0685-3621"
},
{
"name": {
"family": "Hada",
"given": "Kazuhiro"
},
"orcid": "0000-0001-6906-772X"
},
{
"name": {
"family": "Haggard",
"given": "Daryl"
},
"orcid": "0000-0001-6803-2138"
},
{
"name": {
"family": "Haworth",
"given": "Kari"
}
},
{
"name": {
"family": "Hecht",
"given": "Michael H."
},
"orcid": "0000-0002-4114-4583"
},
{
"name": {
"family": "Hesper",
"given": "Ronald"
},
"orcid": "0000-0003-1918-6098"
},
{
"name": {
"family": "Heumann",
"given": "Dirk"
},
"orcid": "0000-0002-7671-0047"
},
{
"name": {
"family": "Ho",
"given": "Luis C."
},
"orcid": "0000-0001-6947-5846"
},
{
"name": {
"family": "Ho",
"given": "Paul"
},
"orcid": "0000-0002-3412-4306"
},
{
"name": {
"family": "Honma",
"given": "Mareki"
},
"orcid": "0000-0003-4058-9000"
},
{
"name": {
"family": "Huang",
"given": "Chih-Wei L."
},
"orcid": "0000-0001-5641-3953"
},
{
"name": {
"family": "Huang",
"given": "Lei"
},
"orcid": "0000-0002-1923-227X"
},
{
"name": {
"family": "Hughes",
"given": "David H."
}
},
{
"name": {
"family": "Ikeda",
"given": "Shiro"
},
"orcid": "0000-0002-2462-1448"
},
{
"name": {
"family": "Impellizzeri",
"given": "C. M. Violette"
},
"orcid": "0000-0002-3443-2472"
},
{
"name": {
"family": "Inoue",
"given": "Makoto"
},
"orcid": "0000-0001-5037-3989"
},
{
"name": {
"family": "Issaoun",
"given": "Sara"
},
"orcid": "0000-0002-5297-921X"
},
{
"name": {
"family": "James",
"given": "David J."
},
"orcid": "0000-0001-5160-4486"
},
{
"name": {
"family": "Jannuzi",
"given": "Buell T."
},
"orcid": "0000-0002-1578-6582"
},
{
"name": {
"family": "Janssen",
"given": "Michael"
},
"orcid": "0000-0001-8685-6544"
},
{
"name": {
"family": "Jeter",
"given": "Britton"
},
"orcid": "0000-0003-2847-1712"
},
{
"name": {
"family": "Jiang",
"given": "Wu"
},
"orcid": "0000-0001-7369-3539"
},
{
"name": {
"family": "Jim\u00e9nez-Rosales",
"given": "Alejandra"
},
"orcid": "0000-0002-2662-3754"
},
{
"name": {
"family": "Johnson",
"given": "Michael D."
},
"orcid": "0000-0002-4120-3029"
},
{
"name": {
"family": "Jorstad",
"given": "Svetlana"
},
"orcid": "0000-0001-6158-1708"
},
{
"name": {
"family": "Joshi",
"given": "Abhishek V."
},
"orcid": "0000-0002-2514-5965"
},
{
"name": {
"family": "Jung",
"given": "Taehyun"
},
"orcid": "0000-0001-7003-8643"
},
{
"name": {
"family": "Karami",
"given": "Mansour"
},
"orcid": "0000-0001-7387-9333"
},
{
"name": {
"family": "Karuppusamy",
"given": "Ramesh"
},
"orcid": "0000-0002-5307-2919"
},
{
"name": {
"family": "Kawashima",
"given": "Tomohisa"
},
"orcid": "0000-0001-8527-0496"
},
{
"name": {
"family": "Keating",
"given": "Garrett K."
},
"orcid": "0000-0002-3490-146X"
},
{
"name": {
"family": "Kettenis",
"given": "Mark"
},
"orcid": "0000-0002-6156-5617"
},
{
"name": {
"family": "Kim",
"given": "Dong-Jin"
},
"orcid": "0000-0002-7038-2118"
},
{
"name": {
"family": "Kim",
"given": "Jae-Young"
},
"orcid": "0000-0001-8229-7183"
},
{
"name": {
"family": "Kim",
"given": "Jongsoo"
},
"orcid": "0000-0002-1229-0426"
},
{
"id": "Kim-Junhan",
"name": {
"family": "Kim",
"given": "Junhan"
},
"orcid": "0000-0002-4274-9373"
},
{
"name": {
"family": "Kino",
"given": "Motoki"
},
"orcid": "0000-0002-2709-7338"
},
{
"name": {
"family": "Koay",
"given": "Jun Yi"
},
"orcid": "0000-0002-7029-6658"
},
{
"name": {
"family": "Kocherlakota",
"given": "Prashant"
},
"orcid": "0000-0001-7386-7439"
},
{
"name": {
"family": "Kofuji",
"given": "Yutaro"
}
},
{
"name": {
"family": "Koch",
"given": "Patrick M."
},
"orcid": "0000-0003-2777-5861"
},
{
"name": {
"family": "Koyama",
"given": "Shoko"
},
"orcid": "0000-0002-3723-3372"
},
{
"name": {
"family": "Kramer",
"given": "Carsten"
},
"orcid": "0000-0002-4908-4925"
},
{
"name": {
"family": "Kramer",
"given": "Michael"
},
"orcid": "0000-0002-4175-2271"
},
{
"name": {
"family": "Krichbaum",
"given": "Thomas P."
},
"orcid": "0000-0002-4892-9586"
},
{
"name": {
"family": "Kuo",
"given": "Cheng-Yu"
},
"orcid": "0000-0001-6211-5581"
},
{
"name": {
"family": "Bella",
"given": "Noemi La"
},
"orcid": "0000-0002-8116-9427"
},
{
"name": {
"family": "Lauer",
"given": "Tod R."
},
"orcid": "0000-0003-3234-7247"
},
{
"name": {
"family": "Lee",
"given": "Daeyoung"
},
"orcid": "0000-0002-3350-5588"
},
{
"name": {
"family": "Lee",
"given": "Sang-Sung"
},
"orcid": "0000-0002-6269-594X"
},
{
"name": {
"family": "Leung",
"given": "Po Kin"
},
"orcid": "0000-0002-8802-8256"
},
{
"id": "Levis-Aviad",
"name": {
"family": "Levis",
"given": "Aviad"
},
"orcid": "0000-0001-7307-632X"
},
{
"name": {
"family": "Li",
"given": "Zhiyuan"
},
"orcid": "0000-0003-0355-6437"
},
{
"name": {
"family": "Lico",
"given": "Rocco"
},
"orcid": "0000-0001-7361-2460"
},
{
"name": {
"family": "Lindahl",
"given": "Greg"
},
"orcid": "0000-0002-6100-4772"
},
{
"name": {
"family": "Lindqvist",
"given": "Michael"
},
"orcid": "0000-0002-3669-0715"
},
{
"name": {
"family": "Lisakov",
"given": "Mikhail"
},
"orcid": "0000-0001-6088-3819"
},
{
"name": {
"family": "Liu",
"given": "Jun"
},
"orcid": "0000-0002-7615-7499"
},
{
"name": {
"family": "Liu",
"given": "Kuo"
},
"orcid": "0000-0002-2953-7376"
},
{
"name": {
"family": "Liuzzo",
"given": "Elisabetta"
},
"orcid": "0000-0003-0995-5201"
},
{
"name": {
"family": "Lo",
"given": "Wen-Ping"
},
"orcid": "0000-0003-1869-2503"
},
{
"name": {
"family": "Lobanov",
"given": "Andrei P."
},
"orcid": "0000-0003-1622-1484"
},
{
"name": {
"family": "Loinard",
"given": "Laurent"
},
"orcid": "0000-0002-5635-3345"
},
{
"name": {
"family": "Lonsdale",
"given": "Colin J."
},
"orcid": "0000-0003-4062-4654"
},
{
"name": {
"family": "Lu",
"given": "Ru-Sen"
},
"orcid": "0000-0002-7692-7967"
},
{
"name": {
"family": "Mao",
"given": "Jirong"
},
"orcid": "0000-0002-7077-7195"
},
{
"name": {
"family": "Marchili",
"given": "Nicola"
},
"orcid": "0000-0002-5523-7588"
},
{
"name": {
"family": "Markoff",
"given": "Sera"
},
"orcid": "0000-0001-9564-0876"
},
{
"name": {
"family": "Marrone",
"given": "Daniel P."
},
"orcid": "0000-0002-2367-1080"
},
{
"name": {
"family": "Marscher",
"given": "Alan P."
},
"orcid": "0000-0001-7396-3332"
},
{
"name": {
"family": "Mart\u00ed-Vidal",
"given": "Iv\u00e1n"
},
"orcid": "0000-0003-3708-9611"
},
{
"name": {
"family": "Matsushita",
"given": "Satoki"
},
"orcid": "0000-0002-2127-7880"
},
{
"name": {
"family": "Matthews",
"given": "Lynn D."
},
"orcid": "0000-0002-3728-8082"
},
{
"name": {
"family": "Medeiros",
"given": "Lia"
},
"orcid": "0000-0003-2342-6728"
},
{
"name": {
"family": "Menten",
"given": "Karl M."
},
"orcid": "0000-0001-6459-0669"
},
{
"name": {
"family": "Michalik",
"given": "Daniel"
},
"orcid": "0000-0002-7618-6556"
},
{
"name": {
"family": "Mizuno",
"given": "Izumi"
},
"orcid": "0000-0002-7210-6264"
},
{
"name": {
"family": "Mizuno",
"given": "Yosuke"
},
"orcid": "0000-0002-8131-6730"
},
{
"name": {
"family": "Moran",
"given": "James M."
},
"orcid": "0000-0002-3882-4414"
},
{
"name": {
"family": "Moriyama",
"given": "Kotaro"
},
"orcid": "0000-0003-1364-3761"
},
{
"name": {
"family": "Moscibrodzka",
"given": "Monika"
},
"orcid": "0000-0002-4661-6332"
},
{
"name": {
"family": "M\u00fcller",
"given": "Cornelia"
},
"orcid": "0000-0002-2739-2994"
},
{
"name": {
"family": "Mus",
"given": "Alejandro"
},
"orcid": "0000-0003-0329-6874"
},
{
"name": {
"family": "Musoke",
"given": "Gibwa"
},
"orcid": "0000-0003-1984-189X"
},
{
"name": {
"family": "Myserlis",
"given": "Ioannis"
},
"orcid": "0000-0003-3025-9497"
},
{
"name": {
"family": "Nadolski",
"given": "Andrew"
},
"orcid": "0000-0001-9479-9957"
},
{
"name": {
"family": "Nagai",
"given": "Hiroshi"
},
"orcid": "0000-0003-0292-3645"
},
{
"name": {
"family": "Nagar",
"given": "Neil M."
},
"orcid": "0000-0001-6920-662X"
},
{
"name": {
"family": "Nakamura",
"given": "Masanori"
},
"orcid": "0000-0001-6081-2420"
},
{
"name": {
"family": "Narayan",
"given": "Ramesh"
},
"orcid": "0000-0002-1919-2730"
},
{
"name": {
"family": "Narayanan",
"given": "Gopal"
},
"orcid": "0000-0002-4723-6569"
},
{
"name": {
"family": "Natarajan",
"given": "Iniyan"
},
"orcid": "0000-0001-8242-4373"
},
{
"name": {
"family": "Nathanail",
"given": "Antonios"
}
},
{
"name": {
"family": "Fuentes",
"given": "Santiago Navarro"
}
},
{
"name": {
"family": "Neilsen",
"given": "Joey"
},
"orcid": "0000-0002-8247-786X"
},
{
"name": {
"family": "Neri",
"given": "Roberto"
},
"orcid": "0000-0002-7176-4046"
},
{
"name": {
"family": "Ni",
"given": "Chunchong"
},
"orcid": "0000-0003-1361-5699"
},
{
"name": {
"family": "Noutsos",
"given": "Aristeidis"
},
"orcid": "0000-0002-4151-3860"
},
{
"name": {
"family": "Nowak",
"given": "Michael A."
},
"orcid": "0000-0001-6923-1315"
},
{
"name": {
"family": "Oh",
"given": "Junghwan"
},
"orcid": "0000-0002-4991-9638"
},
{
"name": {
"family": "Okino",
"given": "Hiroki"
},
"orcid": "0000-0003-3779-2016"
},
{
"name": {
"family": "Olivares",
"given": "H\u00e9ctor"
},
"orcid": "0000-0001-6833-7580"
},
{
"name": {
"family": "Ortiz-Le\u00f3n",
"given": "Gisela N."
},
"orcid": "0000-0002-2863-676X"
},
{
"name": {
"family": "Oyama",
"given": "Tomoaki"
},
"orcid": "0000-0003-4046-2923"
},
{
"name": {
"family": "\u00d6zel",
"given": "Feryal"
},
"orcid": "0000-0003-4413-1523"
},
{
"name": {
"family": "Palumbo",
"given": "Daniel C. M."
},
"orcid": "0000-0002-7179-3816"
},
{
"name": {
"family": "Paraschos",
"given": "Georgios Filippos"
},
"orcid": "0000-0001-6757-3098"
},
{
"name": {
"family": "Park",
"given": "Jongho"
},
"orcid": "0000-0001-6558-9053"
},
{
"name": {
"family": "Parsons",
"given": "Harriet"
},
"orcid": "0000-0002-6327-3423"
},
{
"name": {
"family": "Patel",
"given": "Nimesh"
},
"orcid": "0000-0002-6021-9421"
},
{
"name": {
"family": "Pen",
"given": "Ue-Li"
},
"orcid": "0000-0003-2155-9578"
},
{
"name": {
"family": "Pesce",
"given": "Dominic W."
},
"orcid": "0000-0002-5278-9221"
},
{
"name": {
"family": "Pi\u00e9tu",
"given": "Vincent"
}
},
{
"name": {
"family": "Plambeck",
"given": "Richard"
},
"orcid": "0000-0001-6765-9609"
},
{
"name": {
"family": "PopStefanija",
"given": "Aleksandar"
}
},
{
"name": {
"family": "Porth",
"given": "Oliver"
},
"orcid": "0000-0002-4584-2557"
},
{
"name": {
"family": "P\u00f6tzl",
"given": "Felix M."
},
"orcid": "0000-0002-6579-8311"
},
{
"name": {
"family": "Prather",
"given": "Ben"
},
"orcid": "0000-0002-0393-7734"
},
{
"name": {
"family": "Preciado-L\u00f3pez",
"given": "Jorge A."
},
"orcid": "0000-0002-4146-0113"
},
{
"name": {
"family": "Psaltis",
"given": "Dimitrios"
},
"orcid": "0000-0003-1035-3240"
},
{
"name": {
"family": "Pu",
"given": "Hung-Yi"
},
"orcid": "0000-0001-9270-8812"
},
{
"name": {
"family": "Ramakrishnan",
"given": "Venkatessh"
},
"orcid": "0000-0002-9248-086X"
},
{
"name": {
"family": "Rao",
"given": "Ramprasad"
},
"orcid": "0000-0002-1407-7944"
},
{
"name": {
"family": "Rawlings",
"given": "Mark G."
},
"orcid": "0000-0002-6529-202X"
},
{
"name": {
"family": "Raymond",
"given": "Alexander W."
},
"orcid": "0000-0002-5779-4767"
},
{
"name": {
"family": "Rezzolla",
"given": "Luciano"
},
"orcid": "0000-0002-1330-7103"
},
{
"name": {
"family": "Ricarte",
"given": "Angelo"
},
"orcid": "0000-0001-5287-0452"
},
{
"name": {
"family": "Ripperda",
"given": "Bart"
},
"orcid": "0000-0002-7301-3908"
},
{
"name": {
"family": "Roelofs",
"given": "Freek"
},
"orcid": "0000-0001-5461-3687"
},
{
"name": {
"family": "Rogers",
"given": "Alan"
},
"orcid": "0000-0003-1941-7458"
},
{
"name": {
"family": "Ros",
"given": "Eduardo"
},
"orcid": "0000-0001-9503-4892"
},
{
"name": {
"family": "Romero-Ca\u00f1izales",
"given": "Cristina"
},
"orcid": "0000-0001-6301-9073"
},
{
"name": {
"family": "Roshanineshat",
"given": "Arash"
},
"orcid": "0000-0002-8280-9238"
},
{
"name": {
"family": "Rottmann",
"given": "Helge"
}
},
{
"name": {
"family": "Roy",
"given": "Alan L."
},
"orcid": "0000-0002-1931-0135"
},
{
"name": {
"family": "Ruiz",
"given": "Ignacio"
},
"orcid": "0000-0002-0965-5463"
},
{
"name": {
"family": "Ruszczyk",
"given": "Chet"
},
"orcid": "0000-0001-7278-9707"
},
{
"name": {
"family": "Rygl",
"given": "Kazi L. J."
},
"orcid": "0000-0003-4146-9043"
},
{
"name": {
"family": "S\u00e1nchez",
"given": "Salvador"
},
"orcid": "0000-0002-8042-5951"
},
{
"name": {
"family": "S\u00e1nchez-Arg\u00fcelles",
"given": "David"
},
"orcid": "0000-0002-7344-9920"
},
{
"name": {
"family": "S\u00e1nchez-Portal",
"given": "Miguel"
},
"orcid": "0000-0003-0981-9664"
},
{
"name": {
"family": "Sasada",
"given": "Mahito"
},
"orcid": "0000-0001-5946-9960"
},
{
"name": {
"family": "Satapathy",
"given": "Kaushik"
},
"orcid": "0000-0003-0433-3585"
},
{
"name": {
"family": "Savolainen",
"given": "Tuomas"
},
"orcid": "0000-0001-6214-1085"
},
{
"name": {
"family": "Schloerb",
"given": "F. Peter"
}
},
{
"name": {
"family": "Schonfeld",
"given": "Jonathan"
},
"orcid": "0000-0002-8909-2401"
},
{
"name": {
"family": "Schuster",
"given": "Karl-Friedrich"
},
"orcid": "0000-0003-2890-9454"
},
{
"name": {
"family": "Shao",
"given": "Lijing"
},
"orcid": "0000-0002-1334-8853"
},
{
"name": {
"family": "Shen",
"given": "Zhiqiang"
},
"orcid": "0000-0003-3540-8746"
},
{
"name": {
"family": "Small",
"given": "Des"
},
"orcid": "0000-0003-3723-5404"
},
{
"name": {
"family": "Sohn",
"given": "Bong Won"
},
"orcid": "0000-0002-4148-8378"
},
{
"name": {
"family": "SooHoo",
"given": "Jason"
},
"orcid": "0000-0003-1938-0720"
},
{
"name": {
"family": "Souccar",
"given": "Kamal"
},
"orcid": "0000-0001-7915-5272"
},
{
"id": "Sun-He",
"name": {
"family": "Sun",
"given": "He"
},
"orcid": "0000-0003-1526-6787"
},
{
"name": {
"family": "Tazaki",
"given": "Fumie"
},
"orcid": "0000-0003-0236-0600"
},
{
"name": {
"family": "Tetarenko",
"given": "Alexandra J."
},
"orcid": "0000-0003-3906-4354"
},
{
"name": {
"family": "Tiede",
"given": "Paul"
},
"orcid": "0000-0003-3826-5648"
},
{
"name": {
"family": "Tilanus",
"given": "Remo P. J."
},
"orcid": "0000-0002-6514-553X"
},
{
"name": {
"family": "Titus",
"given": "Michael"
},
"orcid": "0000-0001-9001-3275"
},
{
"name": {
"family": "Torne",
"given": "Pablo"
},
"orcid": "0000-0001-8700-6058"
},
{
"name": {
"family": "Traianou",
"given": "Efthalia"
},
"orcid": "0000-0002-1209-6500"
},
{
"name": {
"family": "Trent",
"given": "Tyler"
}
},
{
"name": {
"family": "Trippe",
"given": "Sascha"
},
"orcid": "0000-0003-0465-1559"
},
{
"name": {
"family": "Turk",
"given": "Matthew"
},
"orcid": "0000-0002-5294-0198"
},
{
"name": {
"family": "van Bemmel",
"given": "Ilse"
},
"orcid": "0000-0001-5473-2950"
},
{
"name": {
"family": "van Langevelde",
"given": "Huib Jan"
},
"orcid": "0000-0002-0230-5946"
},
{
"name": {
"family": "van Rossum",
"given": "Daniel R."
},
"orcid": "0000-0001-7772-6131"
},
{
"name": {
"family": "Vos",
"given": "Jesse"
},
"orcid": "0000-0003-3349-7394"
},
{
"name": {
"family": "Wagner",
"given": "Jan"
},
"orcid": "0000-0003-1105-6109"
},
{
"name": {
"family": "Ward-Thompson",
"given": "Derek"
},
"orcid": "0000-0003-1140-2761"
},
{
"name": {
"family": "Wardle",
"given": "John"
},
"orcid": "0000-0002-8960-2942"
},
{
"name": {
"family": "Weintroub",
"given": "Jonathan"
},
"orcid": "0000-0002-4603-5204"
},
{
"name": {
"family": "Wex",
"given": "Norbert"
},
"orcid": "0000-0003-4058-2837"
},
{
"name": {
"family": "Wharton",
"given": "Robert"
},
"orcid": "0000-0002-7416-5209"
},
{
"name": {
"family": "Wielgus",
"given": "Maciek"
},
"orcid": "0000-0002-8635-4242"
},
{
"name": {
"family": "Wiik",
"given": "Kaj"
},
"orcid": "0000-0002-0862-3398"
},
{
"name": {
"family": "Witzel",
"given": "Gunther"
},
"orcid": "0000-0003-2618-797X"
},
{
"name": {
"family": "Wondrak",
"given": "Michael F."
},
"orcid": "0000-0002-6894-1072"
},
{
"name": {
"family": "Wong",
"given": "George N."
},
"orcid": "0000-0001-6952-2147"
},
{
"name": {
"family": "Wu",
"given": "Qingwen"
},
"orcid": "0000-0003-4773-4987"
},
{
"name": {
"family": "Yamaguchi",
"given": "Paul"
},
"orcid": "0000-0002-6017-8199"
},
{
"name": {
"family": "Yoon",
"given": "Doosoo"
},
"orcid": "0000-0001-8694-8166"
},
{
"name": {
"family": "Young",
"given": "Andr\u00e9"
},
"orcid": "0000-0003-0000-2682"
},
{
"name": {
"family": "Young",
"given": "Ken"
},
"orcid": "0000-0002-3666-4920"
},
{
"name": {
"family": "Younsi",
"given": "Ziri"
},
"orcid": "0000-0001-9283-1191"
},
{
"name": {
"family": "Yuan",
"given": "Feng"
},
"orcid": "0000-0003-3564-6437"
},
{
"name": {
"family": "Yuan",
"given": "Ye-Fei"
},
"orcid": "0000-0002-7330-4756"
},
{
"name": {
"family": "Zensus",
"given": "J. Anton"
},
"orcid": "0000-0001-7470-3321"
},
{
"name": {
"family": "Zhang",
"given": "Shuo"
},
"orcid": "0000-0002-2967-790X"
},
{
"name": {
"family": "Zhao",
"given": "Guang-Yao"
},
"orcid": "0000-0002-4417-1659"
},
{
"name": {
"family": "Zhao",
"given": "Shan-Shan"
},
"orcid": "0000-0002-9774-3606"
},
{
"name": {
"family": "Agurto",
"given": "Claudio"
}
},
{
"name": {
"family": "Araneda",
"given": "Juan Pablo"
}
},
{
"name": {
"family": "Arriagada",
"given": "Oriel"
}
},
{
"name": {
"family": "Bertarini",
"given": "Alessandra"
}
},
{
"name": {
"family": "Berthold",
"given": "Ryan"
}
},
{
"name": {
"family": "Blanchard",
"given": "Jay"
},
"orcid": "0000-0002-2756-395X"
},
{
"name": {
"family": "Brown",
"given": "Ken"
}
},
{
"name": {
"family": "C\u00e1rdenas",
"given": "Mauricio"
}
},
{
"name": {
"family": "Cantzler",
"given": "Michael"
}
},
{
"name": {
"family": "Caro",
"given": "Patricio"
}
},
{
"name": {
"family": "Chuter",
"given": "Tim C."
}
},
{
"name": {
"family": "Ciechanowicz",
"given": "Miroslaw"
}
},
{
"name": {
"family": "Coulson",
"given": "Iain M."
},
"orcid": "0000-0002-7316-4626"
},
{
"name": {
"family": "Crowley",
"given": "Joseph"
}
},
{
"name": {
"family": "Degenaar",
"given": "Nathalie"
},
"orcid": "0000-0002-0092-3548"
},
{
"name": {
"family": "Dornbusch",
"given": "Sven"
},
"orcid": "0000-0003-3211-3352"
},
{
"name": {
"family": "Dur\u00e1n",
"given": "Carlos A."
},
"orcid": "0000-0001-7622-3890"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"name": {
"family": "Geertsema",
"given": "Gertie"
}
},
{
"name": {
"family": "Gonz\u00e1lez",
"given": "Edouard"
}
},
{
"name": {
"family": "Graham",
"given": "Dave"
}
},
{
"name": {
"family": "Gueth",
"given": "Fr\u00e9d\u00e9ric"
}
},
{
"name": {
"family": "Han",
"given": "Chih-Chiang"
}
},
{
"name": {
"family": "Herrera",
"given": "Cristian"
}
},
{
"name": {
"family": "Herrero-Illana",
"given": "Ruben"
},
"orcid": "0000-0002-7758-8717"
},
{
"name": {
"family": "Heyminck",
"given": "Stefan"
}
},
{
"name": {
"family": "Hoge",
"given": "James"
}
},
{
"name": {
"family": "Huang",
"given": "Yau-De"
}
},
{
"name": {
"family": "Jiang",
"given": "Homin"
}
},
{
"name": {
"family": "John",
"given": "David"
}
},
{
"name": {
"family": "Klein",
"given": "Thomas"
}
},
{
"name": {
"family": "Kubo",
"given": "Derek"
}
},
{
"name": {
"family": "Kuroda",
"given": "John"
}
},
{
"name": {
"family": "Kwon",
"given": "Caleb"
},
"orcid": "0000-0001-9006-7345"
},
{
"name": {
"family": "Laing",
"given": "Robert"
},
"orcid": "0000-0001-6786-3087"
},
{
"name": {
"family": "Liu",
"given": "Ching-Tang"
}
},
{
"name": {
"family": "Liu",
"given": "Kuan-Yu"
}
},
{
"name": {
"family": "Mac-Auliffe",
"given": "Felipe"
}
},
{
"name": {
"family": "Martin-Cocher",
"given": "Pierre"
}
},
{
"name": {
"family": "Matulonis",
"given": "Callie"
}
},
{
"name": {
"family": "Messias",
"given": "Hugo"
},
"orcid": "0000-0002-2985-7994"
},
{
"name": {
"family": "Meyer-Zhao",
"given": "Zheng"
}
},
{
"name": {
"family": "Montenegro-Montes",
"given": "Francisco"
},
"orcid": "0000-0002-7430-3771"
},
{
"name": {
"family": "Montgomerie",
"given": "William"
}
},
{
"name": {
"family": "Muders",
"given": "Dirk"
},
"orcid": "0000-0002-2315-2571"
},
{
"name": {
"family": "Nishioka",
"given": "Hiroaki"
}
},
{
"name": {
"family": "Norton",
"given": "Timothy J."
}
},
{
"name": {
"family": "Olivares",
"given": "Rodrigo"
}
},
{
"name": {
"family": "P\u00e9rez-Beaupuits",
"given": "Juan Pablo"
},
"orcid": "0000-0003-3536-2274"
},
{
"name": {
"family": "Parra",
"given": "Rodrigo"
}
},
{
"name": {
"family": "Poirier",
"given": "Michael"
},
"orcid": "0000-0001-6641-0959"
},
{
"name": {
"family": "Pradel",
"given": "Nicolas"
}
},
{
"name": {
"family": "Raffin",
"given": "Philippe A."
}
},
{
"name": {
"family": "Ram\u00edrez",
"given": "Jorge"
}
},
{
"name": {
"family": "Reynolds",
"given": "Mark"
},
"orcid": "0000-0003-1621-9392"
},
{
"name": {
"family": "Saez-Madain",
"given": "Alejandro F."
},
"orcid": "0000-0002-0804-3414"
},
{
"name": {
"family": "Santana",
"given": "Jorge"
}
},
{
"name": {
"family": "Silva",
"given": "Kevin M."
}
},
{
"name": {
"family": "Sousa",
"given": "Don"
},
"orcid": "0000-0002-2625-2607"
},
{
"name": {
"family": "Stahm",
"given": "William"
}
},
{
"name": {
"family": "Torstensson",
"given": "Karl"
}
},
{
"name": {
"family": "Venegas",
"given": "Paulina"
}
},
{
"name": {
"family": "Walther",
"given": "Craig"
}
},
{
"name": {
"family": "Wieching",
"given": "Gundolf"
}
},
{
"name": {
"family": "Wijnands",
"given": "Rudy"
},
"orcid": "0000-0002-3516-2152"
},
{
"name": {
"family": "Wouterloot",
"given": "Jan G. A."
},
"orcid": "0000-0002-4694-6905"
}
]
},
"title": "First Sagittarius A* Event Horizon Telescope Results. II. EHT and Multiwavelength Observations, Data Processing, and Calibration",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Black holes; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 February 28; revised 2022 April 4; accepted 2022 April 10; published 2022 May 12. \n\nWe thank an anonymous referee for their insight and helpful suggestions that have improved this paper. \n\nThe Event Horizon Telescope Collaboration thanks the following organizations and programs: the Academia Sinica; the Academy of Finland (projects 274477, 284495, 312496, 315721); the Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID), Chile via NCN19_058 (TITANs) and Fondecyt 1221421, the Alexander von Humboldt Stiftung; an Alfred P. Sloan Research Fellowship; Allegro, the European ALMA Regional Centre node in the Netherlands, the NL astronomy research network NOVA and the astronomy institutes of the University of Amsterdam, Leiden University and Radboud University; the ALMA North America Development Fund; the Black Hole Initiative, which is funded by grants from the John Templeton Foundation and the Gordon and Betty Moore Foundation (although the opinions expressed in this work are those of the author(s) and do not necessarily reflect the views of these Foundations); Chandra DD7-18089X and TM6-17006X; the China Scholarship Council; China Postdoctoral Science Foundation fellowship (2020M671266); Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT, Mexico, projects U0004-246083, U0004-259839, F0003-272050, M0037-279006, F0003-281692, 104497, 275201, 263356); the Consejer\u00eda de Econom\u00eda, Conocimiento, Empresas y Universidad of the Junta de Andaluc\u00eda (grant P18-FR-1769), the Consejo Superior de Investigaciones Cient\u00edficas (grant 2019AEP112); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Direcci\u00f3n General de Asuntos del Personal Acad\u00e9mico-Universidad Nacional Aut\u00f3noma de M\u00e9xico (DGAPA-UNAM, projects IN112417 and IN112820); the Dutch Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and grant OCENW.KLEIN.113; the Dutch National Supercomputers, Cartesius and Snellius (NWO Grant 2021.013); the EACOA Fellowship awarded by the East Asia Core Observatories Association, which consists of the Academia Sinica Institute of Astronomy and Astrophysics, the National Astronomical Observatory of Japan, Center for Astronomical Mega-Science, Chinese Academy of Sciences, and the Korea Astronomy and Space Science Institute; the European Research Council (ERC) Synergy Grant \"BlackHoleCam: Imaging the Event Horizon of Black Holes\" (grant 610058); the European Union Horizon 2020 research and innovation programme under grant agreements RadioNet (No 730562) and M2FINDERS (No 101018682); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177 and GenT Program (project CIDEGENT/2018/021); MICINN Research Project PID2019-108995GB-C22; the European Research Council for advanced grant \"JETSET: Launching, propagation and emission of relativistic jets from binary mergers and across mass scales\" (Grant No. 884631); the Institute for Advanced Study; the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; DFG research grant \"Jet physics on horizon scales and beyond\" (Grant No. FR 4069/2-1); Joint Princeton/Flatiron and Joint Columbia/Flatiron Postdoctoral Fellowships, research at the Flatiron Institute is supported by the Simons Foundation; the Japan Ministry of Education, Culture, Sports, Science and Technology (MEXT; grant JPMXP1020200109); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); the Joint Institute for Computational Fundamental Science, Japan; the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSW-SLH057, QYZDJSSW-SYS008, ZDBS-LY-SLH011); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP21H01137, JP18H03721, JP18K13594, 18K03709, JP19K14761, 18H01245, 25120007); the Malaysian Fundamental Research Grant Scheme (FRGS) FRGS/1/2019/STG02/UM/02/6; the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (103-2119-M-001-010-MY2, 105-2112-M-001-025-MY3, 105-2119-M-001-042, 106-2112-M-001-011, 106-2119-M-001-013, 106-2119-M-001-027, 106-2923-M-001-005, 107-2119-M-001-017, 107-2119-M-001-020, 107-2119-M-001-041, 107-2119-M-110-005, 107-2923-M-001-009, 108-2112-M-001-048, 108-2112-M-001-051, 108-2923-M-001-002, 109-2112-M-001-025, 109-2124-M-001-005, 109-2923-M-001-001, 110-2112-M-003-007-MY2, 110-2112-M-001-033, 110-2124-M-001-007, and 110-2923-M-001-001); the Ministry of Education (MoE) of Taiwan Yushan Young Scholar Program; the Physics Division, National Center for Theoretical Sciences of Taiwan; the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC20K1567, NASA Astrophysics Theory Program grant 80NSSC20K0527, NASA NuSTAR award 80NSSC20K0645); NASA Hubble Fellowship grant HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555; the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2017YFA0402703, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1440254, AST-1555365, AST-1614868, AST-1615796, AST-1715061, AST-1716327, AST-1716536, OISE-1743747, AST-1816420, AST-1935980, AST-2034306); NSF Astronomy and Astrophysics Postdoctoral Fellowship (AST-1903847); the Natural Science Foundation of China (grants 11650110427, 10625314, 11721303, 11725312, 11873028, 11933007, 11991052, 11991053, 12192220, 12192223); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, the Korea Research Fellowship Program: NRF-2015H1D3A1066561, Brain Pool Program: 2019H1D3A1A01102564, Basic Research Support Grant 2019R1F1A1059721, 2021R1A6A3A01086420, 2022R1C1C1005255); Netherlands Research School for Astronomy (NOVA) Virtual Institute of Accretion (VIA) postdoctoral fellowships; Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648); the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Spanish Ministerio de Ciencia e Innovaci\u00f3n (grants PGC2018-098915-B-C21, AYA2016-80889-P, PID2019-108995GB-C21, PID2020-117404GB-C21); the University of Pretoria for financial aid in the provision of the new Cluster Server nodes and SuperMicro (USA) for a SEEDING GRANT approved towards these nodes in 2020; the Shanghai Pilot Program for Basic Research, Chinese Academy of Science, Shanghai Branch (JCYJ-SHFY-2021-013); the State Agency for Research of the Spanish MCIU through the \"Center of Excellence Severo Ochoa\" award for the Instituto de Astrof\u00edsica de Andaluc\u00eda (SEV-2017- 0709); the Spinoza Prize SPI 78-409; the South African Research Chairs Initiative, through the South African Radio Astronomy Observatory (SARAO, grant ID 77948), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Innovation (DSI) of South Africa; the Toray Science Foundation; Swedish Research Council (VR); the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001); and the YCAA Prize Postdoctoral Fellowship. \n\nWe thank the staff at the participating observatories, correlation centers, and institutions for their enthusiastic support. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2016.1.01154.V. ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), NSF, and National Institutes of Natural Sciences of Japan, together with National Research Council (Canada), Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities, Inc. (AUI)/NRAO, and the National Astronomical Observatory of Japan (NAOJ). The NRAO is a facility of the NSF operated under cooperative agreement by AUI. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. We also thank the Center for Computational Astrophysics, National Astronomical Observatory of Japan. The computing cluster of Shanghai VLBI correlator supported by the Special Fund for Astronomy from the Ministry of Finance in China is acknowledged. \n\nAPEX is a collaboration between the Max-Planck-Institut f\u00fcr Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key Research and Development Program (No. 2017YFA0402700) of China and Natural Science Foundation of China grant 11873028. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. The LMT is a project operated by the Instituto Nacional de Astr\u00f3fisica, \u00d3ptica, y Electr\u00f3nica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30-m telescope on Pico Veleta, Spain is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany) and IGN (Instituto Geogr\u00e1fico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. Support for SPT participation in the EHT is provided by the National Science Foundation through award OPP-1852617 to the University of Chicago. Partial support is also provided by the Kavli Institute of Cosmological Physics at the University of Chicago. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA. \n\nThis work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI-1743442. XSEDE Stampede2 resource at TACC was allocated through TG-AST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. This research is part of the Frontera computing project at the Texas Advanced Computing Center through the Frontera Large-Scale Community Partnerships allocation AST20023. Frontera is made possible by National Science Foundation award OAC-1818253. This research was carried out using resources provided by the Open Science Grid, which is supported by the National Science Foundation and the U.S. Department of Energy Office of Science. Additional work used ABACUS2.0, which is part of the eScience center at Southern Denmark University. Simulations were also performed on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, on the HazelHen cluster at the HLRS in Stuttgart, and on the Pi2.0 and Siyuan Mark-I at Shanghai Jiao Tong University. The computer resources of the Finnish IT Center for Science (CSC) and the Finnish Computing Competence Infrastructure (FCCI) project are acknowledged. This research was enabled in part by support provided by Compute Ontario (http://computeontario.ca), Calcul Quebec (http://www.calculquebec.ca) and Compute Canada (http://www.computecanada.ca). \n\nThe EHTC has received generous donations of FPGA chips from Xilinx Inc., under the Xilinx University Program. The EHTC has benefited from technology shared under open-source license by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). The EHT project is grateful to T4Science and Microsemi for their assistance with Hydrogen Masers. This research has made use of NASA's Astrophysics Data System. We gratefully acknowledge the support provided by the extended staff of the ALMA, both from the inception of the ALMA Phasing Project through the observational campaigns of 2017 and 2018. We would like to thank A. Deller and W. Brisken for EHT-specific support with the use of DiFX. We thank Martin Shepherd for the addition of extra features in the Difmap software that were used for the CLEAN imaging results presented in this paper. We acknowledge the significance that Maunakea, where the SMA and JCMT EHT stations are located, has for the indigenous Hawaiian people. \n\nThe scientific results reported here are also based in part on observations made by the East Asian VLBI Network (EAVN), the Global 3 mm VLBI Array (GMVA), the Very Large Telescope (VLT), the Neil Gehrels Swift Observatory, the Chandra X-ray Observatory, and the Nuclear Spectroscopic Telescope (NuSTAR). We thank the scheduling, data processing, and archive teams from these facilities for making these observations possible. IMV acknowledges the use of LLuis Vives HPC resources of the University of Valencia. \n\nFacility: EHT, ALMA, APEX, IRAM:30 m, JCMT, LMT, SMA, ARO:SMT, SPT, Chandra, EAVN, GMVA, NuSTAR, Swift, VLT. \n\nSoftware: DiFX (Deller et al. 2011), CALC, PolConvert (Mart\u00ed-Vidal et al. 2016), HOPS (Whitney et al. 2004), EHT-HOPS Pipeline (Blackburn et al. 2019), CASA (McMullin et al. 2007), rPICARD (Janssen et al. 2018, 2019b).\n\nPublished - Akiyama_2022_ApJL_930_L13.pdf
",
"abstract": "We present Event Horizon Telescope (EHT) 1.3 mm measurements of the radio source located at the position of the supermassive black hole Sagittarius A* (Sgr A*), collected during the 2017 April 5\u201311 campaign. The observations were carried out with eight facilities at six locations across the globe. Novel calibration methods are employed to account for Sgr A*'s flux variability. The majority of the 1.3 mm emission arises from horizon scales, where intrinsic structural source variability is detected on timescales of minutes to hours. The effects of interstellar scattering on the image and its variability are found to be subdominant to intrinsic source structure. The calibrated visibility amplitudes, particularly the locations of the visibility minima, are broadly consistent with a blurred ring with a diameter of \u223c50 \u03bcas, as determined in later works in this series. Contemporaneous multiwavelength monitoring of Sgr A* was performed at 22, 43, and 86 GHz and at near-infrared and X-ray wavelengths. Several X-ray flares from Sgr A* are detected by Chandra, one at low significance jointly with Swift on 2017 April 7 and the other at higher significance jointly with NuSTAR on 2017 April 11. The brighter April 11 flare is not observed simultaneously by the EHT but is followed by a significant increase in millimeter flux variability immediately after the X-ray outburst, indicating a likely connection in the emission physics near the event horizon. We compare Sgr A*'s broadband flux during the EHT campaign to its historical spectral energy distribution and find that both the quiescent emission and flare emission are consistent with its long-term behavior.",
"date": "2022-05-10",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "930",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L13",
"id_number": "CaltechAUTHORS:20220721-8952000",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220721-8952000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Academia Sinica"
},
{
"agency": "Academy of Finland",
"grant_number": "274477"
},
{
"agency": "Academy of Finland",
"grant_number": "284495"
},
{
"agency": "Academy of Finland",
"grant_number": "312496"
},
{
"agency": "Academy of Finland",
"grant_number": "315721"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1221421"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Allegro"
},
{
"agency": "Nederlandse Onderzoekschool voor de Astronomie (NOVA)"
},
{
"agency": "ALMA North America Development Fund"
},
{
"agency": "Black Hole Initiative"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Gordon and Betty Moore Foundation"
},
{
"agency": "NASA",
"grant_number": "DD7-18089X"
},
{
"agency": "NASA",
"grant_number": "TM6-17006X"
},
{
"agency": "China Scholarship Council"
},
{
"agency": "China Postdoctoral Science Foundation",
"grant_number": "2020M671266"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "U0004-246083"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "U0004-259839"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "F0003-272050"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "M0037-279006"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "F0003-281692"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "104497"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "275201"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "263356"
},
{
"agency": "Junta de Andaluc\u00eda",
"grant_number": "P18-FR-1769"
},
{
"agency": "Consejo Superior de Investigaciones Cient\u00edficas",
"grant_number": "2019AEP112"
},
{
"agency": "Perimeter Institute for Theoretical Physics"
},
{
"agency": "Direcci\u00f3n General de Asuntos del Personal Acad\u00e9mico-Universidad Nacional Aut\u00f3noma de M\u00e9xico (DGAPA-UNAM)",
"grant_number": "IN112417"
},
{
"agency": "Direcci\u00f3n General de Asuntos del Personal Acad\u00e9mico-Universidad Nacional Aut\u00f3noma de M\u00e9xico (DGAPA-UNAM)",
"grant_number": "IN112820"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "639.043.513"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "OCENW.KLEIN.113"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "2021.013"
},
{
"agency": "East Asia Core Observatories Association"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "610058"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "730562"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101018682"
},
{
"agency": "Generalitat Valenciana",
"grant_number": "APOSTD/2018/177"
},
{
"agency": "Generalitat Valenciana",
"grant_number": "CIDEGENT/2018/021"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PID2019-108995GB-C22"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "884631"
},
{
"agency": "Institute for Advanced Study"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "International Max Planck Research School for Astronomy and Astrophysics"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "FR 4069/2-1"
},
{
"agency": "Simons Foundation"
},
{
"agency": "Flatiron Institute"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "JPMXP1020200109"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP17J08829"
},
{
"agency": "Joint Institute for Computational Fundamental Science"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "QYZDJ-SSW-SLH057"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "QYZDJSSW-SYS008"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "ZDBS-LY-SLH011"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18KK0090"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP21H01137"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP18H03721"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP18K13594"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18K03709"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "JP19K14761"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18H01245"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "25120007"
},
{
"agency": "Malaysian Fundamental Research Grant",
"grant_number": "FRGS/1/2019/STG02/UM/02/6"
},
{
"agency": "Massachusetts Institute of Technology (MIT)"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "103-2119-M-001-010-MY2"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "105-2112-M-001-025-MY3"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "105-2119-M-001-042"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2112-M-001-011"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2119-M-001-013"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2119-M-001-027"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "106-2923-M-001-005"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-001-017"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-001-020"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-001-041"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2119-M-110-005"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "107-2923-M-001-009"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "108-2112-M-001-048"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "108-2112-M-001-051"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "108-2923-M-001-002"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "109-2112-M-001-025"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "109-2124-M-001-005"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "109-2923-M-001-001"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2112-M-003-007-MY2"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2112-M-001-033"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2124-M-001-007"
},
{
"agency": "Ministry of Science and Technology (Taipei)",
"grant_number": "110-2923-M-001-001"
},
{
"agency": "Ministry of Education (Taipei)"
},
{
"agency": "National Center for Theoretical Sciences (Taipei)"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1567"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0527"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0645"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51431.001-A"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "National Institute of Natural Sciences (NINS)"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400704"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2017YFA0402703"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400702"
},
{
"agency": "NSF",
"grant_number": "AST-0096454"
},
{
"agency": "NSF",
"grant_number": "AST-0352953"
},
{
"agency": "NSF",
"grant_number": "AST-0521233"
},
{
"agency": "NSF",
"grant_number": "AST-0705062"
},
{
"agency": "NSF",
"grant_number": "AST-0905844"
},
{
"agency": "NSF",
"grant_number": "AST-0922984"
},
{
"agency": "NSF",
"grant_number": "AST-1126433"
},
{
"agency": "NSF",
"grant_number": "AST-1140030"
},
{
"agency": "NSF Graduate Research Fellowship",
"grant_number": "DGE-1144085"
},
{
"agency": "NSF",
"grant_number": "AST-1207704"
},
{
"agency": "NSF",
"grant_number": "AST-1207730"
},
{
"agency": "NSF",
"grant_number": "AST-1207752"
},
{
"agency": "NSF",
"grant_number": "AST-1228509"
},
{
"agency": "NSF",
"grant_number": "OPP-1248097"
},
{
"agency": "NSF",
"grant_number": "AST-1310896"
},
{
"agency": "NSF",
"grant_number": "AST-1440254"
},
{
"agency": "NSF",
"grant_number": "AST-1555365"
},
{
"agency": "NSF",
"grant_number": "AST-1614868"
},
{
"agency": "NSF",
"grant_number": "AST-1615796"
},
{
"agency": "NSF",
"grant_number": "AST-1715061"
},
{
"agency": "NSF",
"grant_number": "AST-1716327"
},
{
"agency": "NSF",
"grant_number": "AST-1716536"
},
{
"agency": "NSF",
"grant_number": "OISE-1743747"
},
{
"agency": "NSF",
"grant_number": "AST-1816420"
},
{
"agency": "NSF",
"grant_number": "AST-1935980"
},
{
"agency": "NSF",
"grant_number": "AST-2034306"
},
{
"agency": "NSF Astronomy and Astrophysics Postdoctoral Fellowship",
"grant_number": "AST-1903847"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11650110427"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "10625314"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11721303"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11725312"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11873028"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11933007"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11991052"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11991053"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12192220"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "12192223"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "National Youth Thousand Talents Program of China"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2015H1A2A1033752"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2015H1D3A1066561"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2019H1D3A1A01102564"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2019R1F1A1059721"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2021R1A6A3A01086420"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "2022R1C1C1005255"
},
{
"agency": "Onsala Space Observatory (OSO)"
},
{
"agency": "Swedish Research Council",
"grant_number": "2017-00648"
},
{
"agency": "Department of Innovation, Science and Economic Development (Canada)"
},
{
"agency": "Ontario Ministry of Research, Innovation and Science"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PGC2018-098915-B-C21"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "AYA2016-80889-P"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PID2019-108995GB-C21"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)",
"grant_number": "PID2020-117404GB-C21"
},
{
"agency": "University of Pretoria"
},
{
"agency": "SuperMicro Corporation"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "JCYJ-SHFY-2021-013"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "SPI 78-409"
},
{
"agency": "South African Radio Astronomy Observatory (SARAO)",
"grant_number": "77948"
},
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "Department of Science and Innovation (South Africa)"
},
{
"agency": "Toray Science Foundation"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "89233218CNA000001"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC05-00OR22725"
},
{
"agency": "Ministry of Finance (China)"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2017YFA0402700"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11873028"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Instituto Geogr\u00e1fico Nacional (IGN)"
},
{
"agency": "State of Arizona"
},
{
"agency": "NSF",
"grant_number": "OPP-1852617"
},
{
"agency": "Kavli Institute for Cosmological Physics"
},
{
"agency": "NSF",
"grant_number": "ACI-1548562"
},
{
"agency": "NSF",
"grant_number": "DBI-0735191"
},
{
"agency": "NSF",
"grant_number": "DBI-1265383"
},
{
"agency": "NSF",
"grant_number": "DBI-1743442"
},
{
"agency": "NSF",
"grant_number": "TG-AST170024"
},
{
"agency": "NSF",
"grant_number": "TG-AST080026N"
},
{
"agency": "NSF",
"grant_number": "AST-170028"
},
{
"agency": "NSF",
"grant_number": "AST-20023"
},
{
"agency": "NSF",
"grant_number": "OAC-1818253"
},
{
"agency": "Compute Ontario"
},
{
"agency": "Calcul Quebec"
},
{
"agency": "Compute Canada"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"corp_creators": {
"items": [
"Event Horizon Telescope Collaboration"
]
},
"doi": "10.3847/2041-8213/ac6675",
"primary_object": {
"basename": "Akiyama_2022_ApJL_930_L13.pdf",
"url": "https://authors.library.caltech.edu/records/z0dap-rsm30/files/Akiyama_2022_ApJL_930_L13.pdf"
},
"pub_year": "2022",
"author_list": "Akiyama, Kazunori; Alberdi, Antxon; et al."
},
{
"id": "https://authors.library.caltech.edu/records/btdzb-xv217",
"eprint_id": 114703,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:28:55",
"lastmod": "2025-11-21 01:57:48",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Lucchini-Matteo",
"name": {
"family": "Lucchini",
"given": "Matteo"
},
"orcid": "0000-0002-2235-3347"
},
{
"id": "Ingram-Adam",
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"id": "van-der-Klis-Michiel",
"name": {
"family": "van der Klis",
"given": "Michiel"
},
"orcid": "0000-0003-0070-9872"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley"
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Remillard-Ron-A",
"name": {
"family": "Remillard",
"given": "Ron A."
},
"orcid": "0000-0003-4815-0481"
},
{
"id": "Cackett-Edward-M",
"name": {
"family": "Cackett",
"given": "Edward M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Uttley-Philip",
"name": {
"family": "Uttley",
"given": "Phil"
},
"orcid": "0000-0001-9355-961X"
},
{
"id": "Altamirano-Diego",
"name": {
"family": "Altamirano",
"given": "Diego"
},
"orcid": "0000-0002-3422-0074"
}
]
},
"title": "The NICER \"Reverberation Machine\": A Systematic Study of Time Lags in Black Hole X-Ray Binaries",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Stellar mass black holes; Astrophysical black holes; Accretion; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 December 1; revised 2022 March 27; accepted 2022 March 28; published 2022 May 2. \n\nWe thank the anonymous referee for helpful comments that improved this work. J.W., G.M., E.K., and J.A.G. acknowledge support from NASA ADAP grant 80NSSC17K0515. J.A.G. thanks support from the Alexander von Humboldt Foundation. A.I. and D.A. acknowledge support from the Royal Society. R.A.R. acknowledges support from NICER grant 80NSSC19K1287.\n\nPublished - Wang_2022_ApJ_930_18.pdf
Accepted Version - 2205.00928.pdf
",
"abstract": "We perform the first systematic search of all NICER archival observations of black hole (and candidate) low-mass X-ray binaries for signatures of reverberation. Reverberation lags result from the light travel time difference between the direct coronal emission and the reflected disk component, and therefore their properties are a useful probe of the disk-corona geometry. We detect new signatures of reverberation lags in eight sources, increasing the total sample from three to 11, and study the evolution of reverberation lag properties as the sources evolve in outbursts. We find that in all of the nine sources with more than one reverberation lag detection, the reverberation lags become longer and dominate at lower Fourier frequencies during the hard-to-soft state transition. This result shows that the evolution in reverberation lags is a global property of the state transitions of black hole low-mass X-ray binaries, which is valuable in constraining models of such state transitions. The reverberation lag evolution suggests that the corona is the base of a jet that vertically expands and/or gets ejected during state transition. We also discover that in the hard state, the reverberation lags get shorter, just as the quasiperiodic oscillations (QPOs) move to higher frequencies, but then in the state transition, while the QPOs continue to higher frequencies, the lags get longer. We discuss the implications of the coronal geometry and physical models of QPOs in light of this new finding.",
"date": "2022-05-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "930",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 18",
"id_number": "CaltechAUTHORS:20220512-561107000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220512-561107000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Royal Society"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1287"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac6262",
"primary_object": {
"basename": "Wang_2022_ApJ_930_18.pdf",
"url": "https://authors.library.caltech.edu/records/btdzb-xv217/files/Wang_2022_ApJ_930_18.pdf"
},
"related_objects": [
{
"basename": "2205.00928.pdf",
"url": "https://authors.library.caltech.edu/records/btdzb-xv217/files/2205.00928.pdf"
}
],
"pub_year": "2022",
"author_list": "Wang, Jingyi; Kara, Erin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tv47w-08477",
"eprint_id": 114296,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:22:08",
"lastmod": "2025-11-21 01:21:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Palmerio-Erika",
"name": {
"family": "Palmerio",
"given": "Erika"
},
"orcid": "0000-0001-6590-3479"
},
{
"id": "Lee-Christina-O",
"name": {
"family": "Lee",
"given": "Christina O."
},
"orcid": "0000-0002-1604-3326"
},
{
"id": "Mays-M-Leila",
"name": {
"family": "Mays",
"given": "M. Leila"
},
"orcid": "0000-0001-9177-8405"
},
{
"id": "Luhmann-Janet-G",
"name": {
"family": "Luhmann",
"given": "Janet G."
},
"orcid": "0000-0003-0626-9353"
},
{
"id": "Lario-David",
"name": {
"family": "Lario",
"given": "David"
},
"orcid": "0000-0002-3176-8704"
},
{
"id": "S\u00e1nchez-Cano-Beatriz",
"name": {
"family": "S\u00e1nchez-Cano",
"given": "Beatriz"
},
"orcid": "0000-0003-0277-3253"
},
{
"id": "Richardson-Ian-G",
"name": {
"family": "Richardson",
"given": "Ian G."
},
"orcid": "0000-0002-3855-3634"
},
{
"id": "Vainio-Rami",
"name": {
"family": "Vainio",
"given": "Rami"
},
"orcid": "0000-0002-3298-2067"
},
{
"id": "Stevens-Michael-L",
"name": {
"family": "Stevens",
"given": "Michael L."
},
"orcid": "0000-0002-7728-0085"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Steinvall-Konrad",
"name": {
"family": "Steinvall",
"given": "Konrad"
},
"orcid": "0000-0002-5861-1643"
},
{
"id": "M\u00f6stl-Christian",
"name": {
"family": "M\u00f6stl",
"given": "Christian"
},
"orcid": "0000-0001-6868-4152"
},
{
"id": "Weiss-Andreas-J",
"name": {
"family": "Weiss",
"given": "Andreas J."
},
"orcid": "0000-0002-6273-4320"
},
{
"id": "Nieves-Chinchilla-Teresa",
"name": {
"family": "Nieves-Chinchilla",
"given": "Teresa"
},
"orcid": "0000-0003-0565-4890"
},
{
"id": "Li-Yan",
"name": {
"family": "Li",
"given": "Yan"
},
"orcid": "0000-0003-4112-3122"
},
{
"id": "Larson-Davin-E",
"name": {
"family": "Larson",
"given": "Davin E."
},
"orcid": "0000-0001-5030-6030"
},
{
"id": "Heyner-Daniel",
"name": {
"family": "Heyner",
"given": "Daniel"
},
"orcid": "0000-0001-7894-8246"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "Stuart D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Galvin-Antoinette-B",
"name": {
"family": "Galvin",
"given": "Antoinette B."
},
"orcid": "0000-0003-3752-5700"
},
{
"id": "Holmstr\u00f6m-Mats",
"name": {
"family": "Holmstr\u00f6m",
"given": "Mats"
},
"orcid": "0000-0001-5494-5374"
},
{
"id": "Khotyaintsev-Yuri-V",
"name": {
"family": "Khotyaintsev",
"given": "Yuri V."
},
"orcid": "0000-0001-5550-3113"
},
{
"id": "Maksimovic-Milan",
"name": {
"family": "Maksimovic",
"given": "Milan"
},
"orcid": "0000-0001-6172-5062"
},
{
"id": "Mitrofanov-Igor-G",
"name": {
"family": "Mitrofanov",
"given": "Igor G."
},
"orcid": "0000-0001-7204-2101"
}
]
},
"title": "CMEs and SEPs During November-December 2020: A Challenge for Real-Time Space Weather Forecasting",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "coronal mass ejections; solar energetic particles; space weather forecasts; MHD models; inner heliosphere; solar wind; Atmospheric Science",
"note": "\u00a9 2022. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 27 April 2022; Version of Record online: 27 April 2022; Accepted manuscript online: 08 April 2022; Manuscript accepted: 28 March 2022; Manuscript revised: 16 March 2022; Manuscript received: 30 November 2021. \n\nE. Palmerio's research was supported by the NASA Living With a Star (LWS) Jack Eddy Postdoctoral Fellowship Program, administered by UCAR's Cooperative Programs for the Advancement of Earth System Science under award no. NNX16AK22G. C. O. Lee acknowledges support from the NASA Mars Atmosphere and Volatile Evolution Project subcontract via Grant Nos. NNH10CC04C, managed by the University of Colorado. C. O. Lee and J. G. Luhmann acknowledge support from the Solar Terrestrial Relations Observatory (STEREO) Project via the STEREO/In situ Measurements of Particles And CME Transients (IMPACT) grant to UC Berkeley. D. Lario and I. G. Richardson acknowledge support from the NASA LWS programs NNH17ZDA001N-LWS and NNH19ZDA001N-LWS, as well as the Goddard Space Flight Center Heliophysics Innovation Fund program. B. S\u00e1nchez-Cano acknowledges support through UK-STFC Ernest Rutherford Fellowship ST/V004115/1 and STFC Grants ST/S000429/1 and ST/V000209/1. K. Steinvall and Y. V. Khotyaintsev acknowledge support from the Swedish Research Council, Grant 2016-05507, and the Swedish National Space Agency, Grant 20/136. C. M\u00f6stl and A. J. Weiss thank the Austrian Science Fund (FWF): P31521-N27, P31659-N27. The Wang-Sheeley-Arge (WSA) model was developed by C. N. Arge (currently at NASA/GSFC), the Enlil model was developed by D. Odstrcil (currently at GMU), and the SEPMOD model was developed by J. Luhmann (currently at UCB). Finally, the authors thank the Mission Teams of all the spacecraft and instruments employed in this study. This work was supported by the NASA's Parker Solar Probe Mission, Contract No. NNN06AA01C. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's LWS program. \n\nData Availability Statement: Simulation results have been provided by the Community Coordinated Modeling Center at Goddard Space Flight Center through their public Runs on Request system (http://ccmc.gsfc.nasa.gov). DONKI runs used in this study: CME1: https://kauai.ccmc.gsfc.nasa.gov/DONKI/view/CMEAnalysis/16146/2. CME2: https://kauai.ccmc.gsfc.nasa.gov/DONKI/view/CMEAnalysis/16172/1. CME3: https://kauai.ccmc.gsfc.nasa.gov/DONKI/view/CMEAnalysis/16186/3. CME4: https://kauai.ccmc.gsfc.nasa.gov/DONKI/view/CMEAnalysis/16204/2. CME5: https://kauai.ccmc.gsfc.nasa.gov/DONKI/view/CMEAnalysis/16219/2. Wang-Sheeley-Arge-Enlil-SEPMOD runs performed in this study: Run1: - Enlil: https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_082921_SH_1. - SEPMOD (GOES-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_1. - SEPMOD (IMP8-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_2. Run2: - Enlil: https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_082921_SH_2. - SEPMOD (GOES-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_3. - SEPMOD (IMP8-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_4. Run3: - Enlil: https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_082921_SH_3. - SEPMOD (GOES-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_5. - SEPMOD (IMP8-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_6. Run4: - Enlil: https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_082921_SH_4. - SEPMOD (GOES-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_7. - SEPMOD (IMP8-like): https://ccmc.gsfc.nasa.gov/results/viewrun.php?domain=SH&runnumber=Erika_Palmerio_090121_SH_8. Remote-sensing data from Solar Dynamics Observatory (SDO), Solar and Heliospheric Observatory (SOHO), and Solar Terrestrial Relations Observatory (STEREO) are openly available at the Virtual Solar Observatory (https://sdac.virtualsolar.org/). These data were processed and analyzed through SunPy (SunPy Community et al., 2020), IDL SolarSoft (Freeland & Handy, 1998), and the European Space Agency (ESA) JHelioviewer software (M\u00fcller et al., 2017). Parker Solar Probe (PSP), STEREO, Wind, and Advanced Composition Explorer (ACE) in situ data are publicly available at NASA's Coordinated Data Analysis Web database (https://cdaweb.sci.gsfc.nasa.gov/index.html/). Mars Atmosphere and Volatile Evolution (MAVEN) data can be accessed at the Planetary Plasma Interactions Node of NASA's Planetary Data System (PDS; https://pds-ppi.igpp.ucla.edu). Mars Express (MEX) data are stored at ESA's Planetary Science Archive (PSA; https://archives.esac.esa.int/psa). Mars Odyssey (MOdy) data are available at the Geosciences Node of the PDS (https://pds-geosciences.wustl.edu/). SOHO particle data can be downloaded from the SOHO/Energetic and Relativistic Nuclei and Electron (ERNE) webpage (https://srl.utu.fi/projects/erne/). The BepiColombo data used in this study are stored at https://doi.org/10.25392/leicester.data.16941040, and the full mission data set will be released in the future at ESA's PSA. Solar Orbiter (SolO) data are openly available at ESA's SolO Archive (http://soar.esac.esa.int/soar/).\n\nPublished - Space_Weather_-_2022_-_Palmerio_-_CMEs_and_SEPs_During_November\u2010December_2020_A_Challenge_for_Real\u2010Time_Space_Weather.pdf
",
"abstract": "Predictions of coronal mass ejections (CMEs) and solar energetic particles (SEPs) are a central issue in space weather forecasting. In recent years, interest in space weather predictions has expanded to include impacts at other planets beyond Earth as well as spacecraft scattered throughout the heliosphere. In this sense, the scope of space weather science now encompasses the whole heliospheric system, and multipoint measurements of solar transients can provide useful insights and validations for prediction models. In this work, we aim to analyze the whole inner heliospheric context between two eruptive flares that took place in late 2020, that is, the M4.4 flare of 29 November and the C7.4 flare of 7 December. This period is especially interesting because the STEREO-A spacecraft was located \u223c60\u00b0 east of the Sun\u2013Earth line, giving us the opportunity to test the capabilities of \"predictions at 360\u00b0\" using remote-sensing observations from the Lagrange L1 and L5 points as input. We simulate the CMEs that were ejected during our period of interest and the SEPs accelerated by their shocks using the WSA-Enlil-SEPMOD modeling chain and four sets of input parameters, forming a \"mini-ensemble.\" We validate our results using in situ observations at six locations, including Earth and Mars. We find that, despite some limitations arising from the models' architecture and assumptions, CMEs and shock-accelerated SEPs can be reasonably studied and forecast in real time at least out to several tens of degrees away from the eruption site using the prediction tools employed here.",
"date": "2022-05",
"date_type": "published",
"publication": "Space Weather",
"volume": "20",
"number": "5",
"publisher": "American Geophysical Union",
"pagerange": "Art. No. e2021SW002993",
"id_number": "CaltechAUTHORS:20220414-26083000",
"issn": "1542-7390",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220414-26083000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Postdoctoral Program",
"grant_number": "NNX16AK22G"
},
{
"agency": "NASA",
"grant_number": "NNH10CC04C"
},
{
"agency": "NASA",
"grant_number": "NNH17ZDA001N-LWS"
},
{
"agency": "NASA",
"grant_number": "NNH19ZDA001N-LWS"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/V004115/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/S000429/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/V000209/1"
},
{
"agency": "Swedish Research Council",
"grant_number": "2016-05507"
},
{
"agency": "Swedish National Space Agency",
"grant_number": "20/136"
},
{
"agency": "FWF Der Wissenschaftsfonds",
"grant_number": "P31521-N27"
},
{
"agency": "FWF Der Wissenschaftsfonds",
"grant_number": "P31659-N27"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1029/2021sw002993",
"primary_object": {
"basename": "Space_Weather_-_2022_-_Palmerio_-_CMEs_and_SEPs_During_November\u2010December_2020_A_Challenge_for_Real\u2010Time_Space_Weather.pdf",
"url": "https://authors.library.caltech.edu/records/tv47w-08477/files/Space_Weather_-_2022_-_Palmerio_-_CMEs_and_SEPs_During_November\u2010December_2020_A_Challenge_for_Real\u2010Time_Space_Weather.pdf"
},
"pub_year": "2022",
"author_list": "Palmerio, Erika; Lee, Christina O.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/k2paj-yx985",
"eprint_id": 114911,
"eprint_status": "archive",
"datestamp": "2023-08-22 15:11:03",
"lastmod": "2025-11-20 23:06:15",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Kosec-Peter",
"name": {
"family": "Kosec",
"given": "Peter"
}
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah"
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "Matthew J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "An 8.56 keV Absorption Line in the Hyperluminous X-Ray Source in NGC 4045: Ultrafast Outflow or Cyclotron Line?",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Ultraluminous x-ray sources; X-ray sources; X-ray transient sources; Neutron stars; Black holes; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2022 January 14; revised 2022 March 8; accepted 2022 March 14; published 2022 April 21. \n\nWe thank the anonymous referee for their review of this manuscript and for their constructive input. \n\nWe wish to thank the Swift PI, Brad Cenko, for approving the target of opportunity requests we made to observe NGC 4045 ULX, as well as the rest of the Swift team for carrying them out. We also acknowledge the use of public data from the Swift data archive. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. \n\nWe also wish to thank the NuSTAR PI, Fiona Harrison, for approving the DDT request we made to observe NGC 4045 ULX, as well as the NuSTAR SOC for carrying out the observation. This work was also supported under NASA contract No. NNG08FD60C. NuSTAR is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nIn addition, we wish to thank Belinda Wilkes, Director of the Chandra X-ray Center for approving the DDT request to observe NGC 4045 ULX and the Chandra team for carrying out the observation. \n\nFinally, we wish to thank Timothy Kallman for help in generating XSTAR models for XSPEC that were used in the analysis. \n\nThis work was also based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. \n\nThis research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. \n\nThe work of D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. \n\nFacilities: Swift - Swift Gamma-Ray Burst Mission, NuSTAR - , CXO - , XMM. - \n\nSoftware: NuSTARDAS, XMMSAS (Gabriel et al. 2004), XSPEC (Arnaud 1996), spex, (Kaastra et al. 1996), hendrics (Bachetti 2015).\n\nPublished - Brightman_2022_ApJ_929_138.pdf
Accepted Version - 2203.11955.pdf
",
"abstract": "We report on the discovery of an absorption line at E 8.56_(-0.11)^(+0.05) keV detected with a significance of >3.3\u03c3 in the NuSTAR and XMM-Newton spectra of a newly discovered hyperluminous X-ray source (L\u2093 > 10\u2074\u00b9 erg s\u207b\u00b9) in the galaxy NGC 4045 at a distance of 32 Mpc. The source was first discovered serendipitously in a Swift/XRT observation of the galaxy, and Swift monitoring reveals a highly variable source changing by over an order of magnitude from maximum to minimum. The origin of the absorption line appears likely to be from highly ionized iron with a blueshift of 0.19c, indicating an ultrafast outflow. However, the large equivalent width of the line (EW = -0.22_(-0.09)^(+0.08) keV) paired with the lack of other absorption lines detected is difficult to reconcile with models. An alternative explanation is that the line is due to a cyclotron resonance scattering feature produced by the interaction of X-ray photons with the powerful magnetic field of a neutron star.",
"date": "2022-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "929",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 138",
"id_number": "CaltechAUTHORS:20220525-90131000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220525-90131000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac5e37",
"primary_object": {
"basename": "2203.11955.pdf",
"url": "https://authors.library.caltech.edu/records/k2paj-yx985/files/2203.11955.pdf"
},
"related_objects": [
{
"basename": "Brightman_2022_ApJ_929_138.pdf",
"url": "https://authors.library.caltech.edu/records/k2paj-yx985/files/Brightman_2022_ApJ_929_138.pdf"
}
],
"pub_year": "2022",
"author_list": "Brightman, Murray; Kosec, Peter; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tjd40-r2m84",
"eprint_id": 113012,
"eprint_status": "archive",
"datestamp": "2023-08-20 07:24:42",
"lastmod": "2025-11-21 03:06:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kakkad-Darshan",
"name": {
"family": "Kakkad",
"given": "D."
},
"orcid": "0000-0002-2603-2639"
},
{
"id": "Sani-E",
"name": {
"family": "Sani",
"given": "E."
}
},
{
"id": "Rojas-Alejandra-F",
"name": {
"family": "Rojas",
"given": "A. F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Mallmann-Nicolas-D",
"name": {
"family": "Mallmann",
"given": "Nicolas D."
},
"orcid": "0000-0001-9159-004X"
},
{
"id": "Veilleux-Sylvain",
"name": {
"family": "Veilleux",
"given": "S."
},
"orcid": "0000-0002-3158-6820"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "F."
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Mushotsky-R",
"name": {
"family": "Mushotsky",
"given": "R."
}
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "E."
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "Nguyen-N",
"name": {
"family": "Nguyen",
"given": "N."
}
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "R."
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "K."
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "M."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Riffel-Rog\u00e9rio-A",
"name": {
"family": "Riffel",
"given": "R."
},
"orcid": "0000-0002-1321-1320"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "B."
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. M."
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "BASS XXXI: Outflow scaling relations in low redshift X-ray AGN host galaxies with MUSE",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: evolution \u2013 galaxies: kinematics and dynamics \u2013 galaxies: nuclei \u2013 galaxies: Seyfert",
"note": "\u00a9 2022 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2022 January 10. Received 2022 January 10; in original form 2021 August 13. Published: 17 January 2022. \n\nWe thank the referee for their useful suggestions. ET and FEB acknowledge support from Agencia Nacional de Investigacion y Desarrollo (ANID) grants CATA-Basal AFB-170002 and FB210003 and Fondo Nacional de Desarrollo Cientifico y Technologico (FONDECYT) Regular grant 1190818. ET acknowledges support from ANID Anillo ACT172033 and Millennium Nucleus NCN19_058 (TITANs). FEB acknowledges support from FONDECYT regular grant 1200495, Millennium Science Initiative ICN12_009. ARL acknowledges support from FONDECYT Postdoctorado project No. 3210157. MK acknowledges support from National Aeronautics and Space Administration (NASA) through Astrophysics Data Analysis Programme (ADAP) award NNH16CT03C. KO acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). CR acknowledges support from the Fondecyt Iniciacion grant 11190831 and ANID BASAL project FB210003. BT acknowledges support from the Israel Science Foundation (grant number 1849/19) and from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement number 950533). DK, ES, NDM, and NG acknowledge the support from ESO for their studentship programme and Science Support Discretionary Funds. NDM and NG are grateful for the hospitality by ESO-Chile. FR acknowledges support from Progetti di Ricerca di Interesse Nazionale (PRIN) MIUR 2017 project 'Black Hole winds and the Baryon Life Cycle of galaxies: the stone-guest at the galaxy evolution supper', contract 2017PH3WAT. RR thanks Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq, Proj. 311223/2020-6, 304927/2017-1, and 400352/2016-8), Funda\u00e7\u00e3o de amparo 'a pesquisa do Rio Grande do Sul (FAPERGS, Proj. 16/2551-0000251-7 and 19/1750-2), Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES, Proj. 0001). Based on observations made with ESO telescopes at the La Silla Paranal Observatory under programmes 60.A-9100(K), 60.A-9339(A), 094.B-298, 094.B-0321, 094.B-0345, 095.B-0015, 095.B-0482, 095.B-0532, 095.B-0934, 096.D-0263, 096.B-0309, 097.B-0080, 097.D-0408, 099.B-0137, 0100.B-0116. \n\nData Availability: All the raw data analysed in this paper are publicly available in the ESO archive. The respective programme IDs from which these data are obtained are mentioned in the footnote in Section 2.\n\nPublished - stac103.pdf
Accepted Version - 2201.04149.pdf
Supplemental Material - stac103_supplemental_file.pdf
",
"abstract": "Ionized gas kinematics provide crucial evidence of the impact that active galactic nuclei (AGNs) have in regulating star formation in their host galaxies. Although the presence of outflows in AGN host galaxies has been firmly established, the calculation of outflow properties such as mass outflow rates and kinetic energy remains challenging. We present the [O\u2009III]\u03bb5007 ionized gas outflow properties of 22 z<0.1 X-ray AGN, derived from the BAT AGN Spectroscopic Survey using MUSE/VLT. With an average spatial resolution of 1 arcsec (0.1\u20131.2 kpc), the observations resolve the ionized gas clouds down to sub-kiloparsec scales. Resolved maps show that the [O\u2009III] velocity dispersion is, on average, higher in regions ionized by the AGN, compared to star formation. We calculate the instantaneous outflow rates in individual MUSE spaxels by constructing resolved mass outflow rate maps, incorporating variable outflow density and velocity. We compare the instantaneous values with time-averaged outflow rates by placing mock fibres and slits on the MUSE field-of-view, a method often used in the literature. The instantaneous outflow rates (0.2\u2013275 M\u2299 yr\u207b\u00b9) tend to be two orders of magnitude higher than the time-averaged outflow rates (0.001\u201340 M\u2299 yr\u207b\u00b9). The outflow rates correlate with the AGN bolometric luminosity (L_(bol) \u223c 10^(42.71)\u201310^(45.62) erg\u2009s\u207b\u00b9) but we find no correlations with black hole mass (10^(6.1)\u201310^(8.9) M\u2299), Eddington ratio (0.002\u20131.1), and radio luminosity (10\u00b2\u00b9\u201310\u00b2\u2076 W\u2009Hz\u207b\u00b9). We find the median coupling between the kinetic energy and L_(bol) to be 1 per\u2009cent, consistent with the theoretical predictions for an AGN-driven outflow.",
"date": "2022-04",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "511",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2105-2124",
"id_number": "CaltechAUTHORS:20220119-234010540",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220119-234010540",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "BASAL-CATA",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3210157"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca (MIUR)",
"grant_number": "2017PH3WAT"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "311223/2020-6"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "304927/2017-1"
},
{
"agency": "Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)",
"grant_number": "400352/2016-8"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "16/2551-0000251-7"
},
{
"agency": "Funda\u00e7\u00e3o de Amparo \u00e0 pesquisa do Estado do Rio Grande do Sul (FAPERGS)",
"grant_number": "19/1750-2"
},
{
"agency": "Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)",
"grant_number": "0001"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stac103",
"primary_object": {
"basename": "stac103_supplemental_file.pdf",
"url": "https://authors.library.caltech.edu/records/tjd40-r2m84/files/stac103_supplemental_file.pdf"
},
"related_objects": [
{
"basename": "2201.04149.pdf",
"url": "https://authors.library.caltech.edu/records/tjd40-r2m84/files/2201.04149.pdf"
},
{
"basename": "stac103.pdf",
"url": "https://authors.library.caltech.edu/records/tjd40-r2m84/files/stac103.pdf"
}
],
"pub_year": "2022",
"author_list": "Kakkad, D.; Sani, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2jepy-bra36",
"eprint_id": 113708,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:49:22",
"lastmod": "2025-11-20 23:31:31",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mori-Kaya",
"name": {
"family": "Mori",
"given": "Kaya"
},
"orcid": "0000-0002-9709-5389"
},
{
"id": "Hailey-Charles",
"name": {
"family": "Hailey",
"given": "Charles"
},
"orcid": "0000-0002-3681-145X"
},
{
"id": "Bridges-Gabriel",
"name": {
"family": "Bridges",
"given": "Gabriel"
}
},
{
"id": "Mandel-Shifra",
"name": {
"family": "Mandel",
"given": "Shifra"
},
"orcid": "0000-0002-6126-7409"
},
{
"id": "Garvin-Amani",
"name": {
"family": "Garvin",
"given": "Amani"
}
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Dunn-William",
"name": {
"family": "Dunn",
"given": "William"
},
"orcid": "0000-0002-0383-6917"
},
{
"id": "Hord-Benjamin-J",
"name": {
"family": "Hord",
"given": "Benjamin J."
},
"orcid": "0000-0001-5084-4269"
},
{
"id": "Branduardi-Raymont-Graziella",
"name": {
"family": "Branduardi-Raymont",
"given": "Graziella"
},
"orcid": "0000-0002-6620-6357"
},
{
"id": "Clarke-John",
"name": {
"family": "Clarke",
"given": "John"
}
},
{
"id": "Jackman-Caitriona",
"name": {
"family": "Jackman",
"given": "Caitriona"
},
"orcid": "0000-0003-0635-7361"
},
{
"id": "Nynka-Melania",
"name": {
"family": "Nynka",
"given": "Melania"
},
"orcid": "0000-0002-3310-1946"
},
{
"id": "Ray-Licia",
"name": {
"family": "Ray",
"given": "Licia"
},
"orcid": "0000-0003-3727-602X"
}
]
},
"title": "Observation and origin of non-thermal hard X-rays from Jupiter",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Giant planets; High-energy astrophysics; Astronomy and Astrophysics",
"note": "\u00a9 2022 Nature Publishing Group. \n\nReceived 17 February 2021; Accepted 16 December 2021; Published 10 February 2022. \n\nWe thank R. Wilson for his help in analysing JADE data. We also thank the MOP group of LASP for their work on Juno's trajectory and magnetic footprint. We acknowledge D. Wik for his help in analysing NuSTAR background data. Support for this work by K.M. was provided by NASA through NuSTAR Cycle 3 Guest Observer Program grant number NNH16ZDA001N. Support for this work by C.J. at DIAS was supported by the Science Foundation Ireland grant number 18/FRL/6199. \n\nData availability: The NuSTAR and XMM-Newton data are archived at NASA's HEASARC website (https://heasarc.gsfc.nasa.gov). The JEDI, JADE and MAG data are available at the Planetary Data System(https://pds-ppi.igpp.ucla.edu). The magnetic footprint of JUNO is available through the LASP MOP group's website (https://lasp.colorado.edu/home/mop/missions/juno/trajectory-information/). \n\nCode availability: NuSTAR and XMM-Newton data were analysed by HEASOFT version 6.28 and SAS analysis software version 16.1.0, respectively. GEANT4 is publicly available at https://geant4.web.cern.ch. The simulation and data reduction code is available from the corresponding author upon request. \n\nContributions: K.M., C.H., G.B. and S.M. wrote the manuscript and made large contributions to data analysis and interpretation. G.B. performed the JADE/JEDI data analysis and GEANT4 simulations. S.M. and B.J.H. analysed NuSTAR data. B.G. contributed to NuSTAR data analysis and interpretation. A.G. and W.D. were involved with XMM-Newton data analysis. J.C. and M.N. conducted a feasibility study of NuSTAR observations of Jupiter. G.B.-R., C.J. and L.R. interpreted the analysis results and provided insights into Jovian aurora physics. All authors contributed to discussing the results and commented on the manuscript. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Astronomy thanks Tomoki Kimura and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\nMori, K., Hailey, C., Bridges, G. et al. Publisher Correction: Observation and origin of non-thermal hard X-rays from Jupiter. Nat Astron (2022). https://doi.org/10.1038/s41550-022-01652-9\n\nSupplemental Material - 41550_2021_1594_Fig5_ESM.webp
Supplemental Material - 41550_2021_1594_Fig6_ESM.webp
Supplemental Material - 41550_2021_1594_Tab1_ESM.webp
Supplemental Material - 41550_2021_1594_Tab2_ESM.webp
",
"abstract": "Electrons accelerated on Earth by a rich variety of wave-scattering or stochastic processes generate hard, non-thermal X-ray bremsstrahlung up to ~1\u2009MeV (refs.\u20093,4) and power Earth's various types of aurorae. Although Jupiter's magnetic field is an order of magnitude larger than Earth's, space-based telescopes have previously detected X-rays only up to ~7\u2009keV (ref.\u20095). On the basis of theoretical models of the Jovian auroral X-ray production, X-ray emission in the ~2\u20137\u2009keV band has been interpreted as thermal (arising from electrons characterized by a Maxwell\u2013Boltzmann distribution) bremsstrahlung. Here we report the observation of hard X-rays in the 8\u201320\u2009keV band from the Jovian aurorae, obtained with the NuSTAR X-ray observatory. The X-rays fit to a flat power-law model with slope of 0.60\u2009\u00b1\u20090.22\u2014a spectral signature of non-thermal, hard X-ray bremsstrahlung. We determine the electron flux and spectral shape in the kiloelectronvolt to megaelectronvolt energy range using coeval in situ measurements taken by the Juno spacecraft's JADE and JEDI instruments. Jovian electron spectra of the form we observe have previously been interpreted as arising in stochastic acceleration, rather than coherent acceleration by electric fields. We reproduce the X-ray spectral shape and approximate flux observed by NuSTAR, and explain the non-detection of hard X-rays by Ulysses, by simulating the non-thermal population of electrons undergoing precipitating electron energy loss, secondary electron generation and bremsstrahlung emission in a model Jovian atmosphere. The results highlight the similarities between the processes generating hard X-ray aurorae on Earth and Jupiter, which may be occurring on Saturn, too.",
"date": "2022-04",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "6",
"number": "4",
"publisher": "Nature Publishing Group",
"pagerange": "442-448",
"id_number": "CaltechAUTHORS:20220303-310356500",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220303-310356500",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16ZDA001N"
},
{
"agency": "Science Foundation, Ireland",
"grant_number": "18/FRL/6199"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41550-021-01594-8",
"primary_object": {
"basename": "41550_2021_1594_Fig5_ESM.webp",
"url": "https://authors.library.caltech.edu/records/2jepy-bra36/files/41550_2021_1594_Fig5_ESM.webp"
},
"related_objects": [
{
"basename": "41550_2021_1594_Fig6_ESM.webp",
"url": "https://authors.library.caltech.edu/records/2jepy-bra36/files/41550_2021_1594_Fig6_ESM.webp"
},
{
"basename": "41550_2021_1594_Tab1_ESM.webp",
"url": "https://authors.library.caltech.edu/records/2jepy-bra36/files/41550_2021_1594_Tab1_ESM.webp"
},
{
"basename": "41550_2021_1594_Tab2_ESM.webp",
"url": "https://authors.library.caltech.edu/records/2jepy-bra36/files/41550_2021_1594_Tab2_ESM.webp"
}
],
"pub_year": "2022",
"author_list": "Mori, Kaya; Hailey, Charles; et al."
},
{
"id": "https://authors.library.caltech.edu/records/cd721-3vk12",
"eprint_id": 113003,
"eprint_status": "archive",
"datestamp": "2023-10-09 15:36:46",
"lastmod": "2025-11-21 00:59:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "O'Connor-Brendan",
"name": {
"family": "O'Connor",
"given": "B."
},
"orcid": "0000-0002-9700-0036"
},
{
"name": {
"family": "G\u00f6\u011f\u00fc\u015f",
"given": "E."
},
"orcid": "0000-0002-5274-6790"
},
{
"name": {
"family": "Huppenkothen",
"given": "D."
},
"orcid": "0000-0002-1169-7486"
},
{
"name": {
"family": "Kouveliotou",
"given": "C."
},
"orcid": "0000-0003-1443-593X"
},
{
"name": {
"family": "Gorgone",
"given": "N."
},
"orcid": "0000-0002-1653-6411"
},
{
"name": {
"family": "Townsend",
"given": "L. J."
},
"orcid": "0000-0001-9788-3345"
},
{
"name": {
"family": "Calamida",
"given": "A."
},
"orcid": "0000-0002-0882-7702"
},
{
"name": {
"family": "Fruchter",
"given": "A."
},
"orcid": "0000-0002-6652-9279"
},
{
"name": {
"family": "Buckley",
"given": "D. A. H."
},
"orcid": "0000-0002-7004-9956"
},
{
"name": {
"family": "Baring",
"given": "M. G."
},
"orcid": "0000-0003-4433-1365"
},
{
"name": {
"family": "Kennea",
"given": "J. A."
},
"orcid": "0000-0002-6745-4790"
},
{
"name": {
"family": "Younes",
"given": "G."
},
"orcid": "0000-0002-7991-028X"
},
{
"name": {
"family": "Arzoumanian",
"given": "Z."
}
},
{
"name": {
"family": "Bellm",
"given": "E."
},
"orcid": "0000-0001-8018-5348"
},
{
"name": {
"family": "Cenko",
"given": "S. B."
},
"orcid": "0000-0003-1673-970X"
},
{
"name": {
"family": "Gendreau",
"given": "K."
},
"orcid": "0000-0001-7115-2819"
},
{
"id": "Granot-Jonathan",
"name": {
"family": "Granot",
"given": "J."
},
"orcid": "0000-0001-8530-8941"
},
{
"name": {
"family": "Hailey",
"given": "C."
},
"orcid": "0000-0002-3681-145X"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Hartmann",
"given": "D."
},
"orcid": "0000-0002-8028-0991"
},
{
"name": {
"family": "Kaper",
"given": "L."
},
"orcid": "0000-0001-8025-8981"
},
{
"name": {
"family": "Kutyrev",
"given": "A."
},
"orcid": "0000-0002-2715-8460"
},
{
"name": {
"family": "Slane",
"given": "P. O."
},
"orcid": "0000-0002-6986-6756"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Troja",
"given": "E."
},
"orcid": "0000-0002-1869-7817"
},
{
"name": {
"family": "van der Horst",
"given": "A. J."
},
"orcid": "0000-0001-9149-6707"
},
{
"name": {
"family": "Wijers",
"given": "R. A. M. J."
},
"orcid": "0000-0002-3101-1808"
},
{
"name": {
"family": "Woudt",
"given": "P."
},
"orcid": "0000-0002-6896-1655"
}
]
},
"title": "Identification of an X-Ray Pulsar in the BeXRB System IGR J18219\u22121347",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray astronomy; High mass x-ray binary stars; Pulsars; Neutron stars",
"note": "\u00a9 2022 The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 November 24; revised 2022 January 21; accepted 2022 January 24; published 2022 March 10. \n\nThe authors acknowledge useful discussions with Matteo Bachetti, Tomaso Belloni, and Oleg Kargaltsev. B.O., C.K., and N.G. acknowledge supported under NASA Grants 80NSSC20K0389 and 80NSSC19K091. L.J.T. is supported by the South African National Research Foundation. J.G. acknowledges support by the ISF-NSFC joint research program (grant No. 3296/19). \n\nThis work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (Caltech, USA). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. The scientific results reported in this article are based on observations made by the Chandra X-ray Observatory. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application package CIAO. These results also made use of Lowell Observatory's Lowell Discovery Telescope (LDT), formerly the Discovery Channel Telescope. Lowell operates the LDT in partnership with Boston University, Northern Arizona University, the University of Maryland, and the University of Toledo. Partial support of the LDT was provided by Discovery Communications. LMI was built by Lowell Observatory using funds from the National Science Foundation (AST-1005313). Some of the observations reported in this paper were obtained with the Southern African Large Telescope (SALT) under program 2018-2-LSP-001. We additionally made use of Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013). \n\nFacilities: Swift - Swift Gamma-Ray Burst Mission, NuSTAR - , NICER - , SALT - , LDT - , UKIRT - , ZTF - , PS1. - \n\nSoftware: HEASoft v6.27.2, XRTDAS, NuSTARDAS v1.9.2, NICERDAS v7a, XSPEC v12.11.0 (Arnaud 1996), IRAF (Tody 1986), DAOPHOT (Stetson 1987), SExtractor (Bertin & Arnouts 1996), Swarp (Bertin 2010), SCAMP (Bertin 2006), astrometry.net (Lang et al. 2010), Stingray (Huppenkothen et al. 2019), Astropy (Astropy Collaboration et al. 2013).\n\nPublished - OConnor_2022_ApJ_927_139.pdf
Submitted - 2111-12592.pdf
",
"abstract": "We report on observations of the candidate Be/X-ray binary (BeXRB) IGR J18219\u22121347 with the Swift/X-ray Telescope, the Nuclear Spectroscopic Telescope ARray, and the Neutron Star Interior Composition Explorer during Type-I outbursts in 2020 March and June. Our timing analysis revealed the spin period of a neutron star with P_(spin) = 52.46 s. This periodicity, combined with the known orbital period of 72.4 days, indicates that the system is a BeXRB. Furthermore, by comparing the spectral energy distribution of the infrared counterpart to that of known BeXRBs, we confirm this classification and set a distance of approximately 10\u201315 kpc for the source. The broadband X-ray spectrum (1.5\u201350 keV) of the source is described by an absorbed power law with a photon index \u0393 \u223c 0.5 and a cutoff energy at \u223c13 keV.",
"date": "2022-03-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "927",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 139",
"id_number": "CaltechAUTHORS:20220119-233939590",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220119-233939590",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K0389"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K091"
},
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "Israel Science Foundation"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "3296/19"
},
{
"agency": "NSF",
"grant_number": "AST-1005313"
},
{
"agency": "Southern African Large Telescope (SALT)",
"grant_number": "2018-2-LSP-001"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac5032",
"primary_object": {
"basename": "2111-12592.pdf",
"url": "https://authors.library.caltech.edu/records/cd721-3vk12/files/2111-12592.pdf"
},
"related_objects": [
{
"basename": "OConnor_2022_ApJ_927_139.pdf",
"url": "https://authors.library.caltech.edu/records/cd721-3vk12/files/OConnor_2022_ApJ_927_139.pdf"
}
],
"pub_year": "2022",
"author_list": "O'Connor, B.; G\u00f6\u011f\u00fc\u015f, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/hz6p5-eta78",
"eprint_id": 113722,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:32:51",
"lastmod": "2025-11-21 01:58:36",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Negoro-Hitoshi",
"name": {
"family": "Negoro",
"given": "Hitoshi"
},
"orcid": "0000-0003-0939-1178"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "McKinley"
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Hare-Jeremy",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Mihara-Tatehiro",
"name": {
"family": "Mihara",
"given": "Tatehiro"
},
"orcid": "0000-0002-6337-7943"
},
{
"id": "Shidatsu-Megumi",
"name": {
"family": "Shidatsu",
"given": "Megumi"
},
"orcid": "0000-0001-8195-6546"
},
{
"id": "Sugizaka-Mutsumi",
"name": {
"family": "Sugizaki",
"given": "Mutsumi"
},
"orcid": "0000-0002-1190-0720"
},
{
"id": "Takagi-Ryohei",
"name": {
"family": "Takagi",
"given": "Ryohei"
}
}
]
},
"title": "MAXI and NuSTAR Observations of the Faint X-Ray Transient MAXI J1848-015 in the GLIMPSE-C01 Cluster",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Black holes; High energy astrophysics; Compact objects; Stellar mass black holes; X-ray binary stars; Accretion; Neutron stars",
"note": "\u00a9 2022 The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 November 9; revised 2022 January 20; accepted 2022 February 5; published 2022 March 15. \n\nThis work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nR.M.L. acknowledges the support of NASA through Hubble Fellowship Program grant HST-HF2-51440.001. J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the Universities Space Research Association under contract with NASA. A.J. would like to acknowledge support from Chandra X-ray Observatory Center's grant GO0-21067X. \n\nThis work also made use of MAXI data provided by RIKEN, JAXA, and the MAXI team. Part of this work was financially supported by Grants-in-Aid for Scientific Research 21K03620 (H.N.), 17H06362 (H.N.), and 19K14762 (M.S.) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. \n\nFinally, we would like to thank the anonymous reviewer, whose comments and suggestions significantly improved the quality of this work. \n\nSoftware: Astropy (Astropy Collaboration et al. 2013, 2018), Corner (Foreman-Mackey 2016), DS9 (Joye & Mandel 2003), Matplotlib (Hunter 2007), Scipy (Virtanen et al. 2020), Stingray (Huppenkothen et al. 2019), relxill (Dauser et al. 2014; Garc\u00eda et al. 2014), XSpec (Arnaud 1996).\n\nPublished - Pike_2022_ApJ_927_190.pdf
Accepted Version - 2202.02883.pdf
",
"abstract": "We present the results of Monitor of All-sky X-ray Image (MAXI) monitoring and two Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the recently discovered faint X-ray transient MAXI J1848015. Analysis of the MAXI light curve shows that the source underwent a rapid flux increase beginning on 2020 December 20, followed by a rapid decrease in flux after only \u223c5 days. NuSTAR observations reveal that the source transitioned from a bright soft state with unabsorbed, bolometric (0.1\u2013100 keV) flux F = 6.9 \u00b1 0.1 \u00d7 10\u207b\u00b9\u2070 erg cm\u207b\u00b2 s\u207b\u00b9, to a low hard state with flux F = 2.85 \u00b1 0.04 \u00d7 10\u207b\u00b9\u2070 erg cm\u207b\u00b2 s\u207b\u00b9. Given a distance of 3.3 kpc, inferred via association of the source with the GLIMPSE-C01 cluster, these fluxes correspond to an Eddington fraction of the order of 10\u207b\u00b3 for an accreting neutron star (NS) of mass M = 1.4M\u2299, or even lower for a more massive accretor. However, the source spectra exhibit strong relativistic reflection features, indicating the presence of an accretion disk that extends close to the accretor, for which we measure a high spin, a = 0.967 \u00b1 0.013. In addition to a change in flux and spectral shape, we find evidence for other changes between the soft and hard states, including moderate disk truncation with the inner disk radius increasing from R_(in) \u2248 3 R_g to R_(in) \u2248 8 R_g, narrow Fe emission whose centroid decreases from 6.8 \u00b1 0.1 keV to 6.3 \u00b1 0.1 keV, and an increase in low-frequency (10\u207b\u00b3\u201310\u207b\u00b9 Hz) variability. Due to the high spin, we conclude that the source is likely to be a black hole rather than an NS, and we discuss physical interpretations of the low apparent luminosity as well as the narrow Fe emission.",
"date": "2022-03-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "927",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 190",
"id_number": "CaltechAUTHORS:20220304-000054911",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220304-000054911",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "NASA",
"grant_number": "GO0-21067X"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "21K03620"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "17H06362"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "19K14762"
},
{
"agency": "NASA Einstein Fellowship"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac5258",
"primary_object": {
"basename": "2202.02883.pdf",
"url": "https://authors.library.caltech.edu/records/hz6p5-eta78/files/2202.02883.pdf"
},
"related_objects": [
{
"basename": "Pike_2022_ApJ_927_190.pdf",
"url": "https://authors.library.caltech.edu/records/hz6p5-eta78/files/Pike_2022_ApJ_927_190.pdf"
}
],
"pub_year": "2022",
"author_list": "Pike, Sean N.; Negoro, Hitoshi; et al."
},
{
"id": "https://authors.library.caltech.edu/records/bacqt-a9668",
"eprint_id": 116246,
"eprint_status": "archive",
"datestamp": "2023-08-20 07:14:10",
"lastmod": "2025-11-20 20:56:19",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Zoglauer-Andreas",
"name": {
"family": "Zoglauer",
"given": "Andreas"
},
"orcid": "0000-0001-9067-3150"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Reconstruction of the NuSTAR PSF Using Single-laser Metrology",
"ispublished": "unpub",
"full_text_status": "restricted",
"note": "\u00a9 2022 IEEE. \n\nThis work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology.",
"abstract": "This paper describes a method by which the metrology system of the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray space observatory, which uses two lasers to characterize the relative motion of the optics and focal plane benches, can be approximated if one laser fails. The optics and focal plane benches are separated by a ten-meter-long rigid mast that undergoes small amounts of thermal flexing depending on how the spacecraft is illuminated by the Sun. Compensation for this motion is required in order to produce an in-focus image. We analyze the trends of mast motion by observation parameters, using archival NuSTAR data between 2012 and 2021, in order to discover whether parameters such as the solar aspect angle (SAA) can be used to predict the mast motion in future observations. We find that, by using the SAA, observation date, and orbital phase, we can simulate the motion measured by one of the lasers by translating the track produced by the other laser and applying modifications to the mast aspect solution calculated during the NuSTAR data reduction pipeline. With this simulated mast solution, we are able to reconstruct a minimally distorted point spread function for all but two narrow ranges of SAA. We plan to implement the generation of simulated mast files alongside the usual NuSTAR data reduction pipeline for contingency purposes should a laser on the spacecraft fail in the future. This work also has implications for reducing the risk of implementing laser metrology systems on future missions that use deployable masts to achieve the long focal lengths required in high-energy astronomy.",
"date": "2022-03-05",
"date_type": "published",
"publisher": "IEEE",
"place_of_pub": "Piscataway, NJ",
"pagerange": "1-8",
"id_number": "CaltechAUTHORS:20220811-935515000",
"isbn": "978-1-6654-3760-8",
"book_title": "2022 IEEE Aerospace Conference (AERO)",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220811-935515000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1109/aero53065.2022.9843468",
"pub_year": "2022",
"author_list": "Earnshaw, Hannah P.; Madsen, Kristin K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3mzv9-ab577",
"eprint_id": 113812,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:28:42",
"lastmod": "2025-11-20 21:47:08",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Cackett-Edward-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Miller-Jon-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Stevens-Abigail-L",
"name": {
"family": "Stevens",
"given": "A. L."
},
"orcid": "0000-0002-5041-3079"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Homan-Jeroen",
"name": {
"family": "Homan",
"given": "J."
},
"orcid": "0000-0001-8371-2713"
},
{
"id": "Ng-Mason",
"name": {
"family": "Ng",
"given": "M."
},
"orcid": "0000-0002-0940-6563"
},
{
"id": "Guillot-Sebastien",
"name": {
"family": "Guillot",
"given": "S."
},
"orcid": "0000-0002-6449-106X"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
}
},
{
"id": "Chakrabarty-Deepto",
"name": {
"family": "Chakrabarty",
"given": "D."
},
"orcid": "0000-0001-8804-8946"
}
]
},
"title": "Radius Constraints from Reflection Modeling of Cygnus X-2 with NuSTAR and NICER",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Neutron stars; Low-mass x-ray binary stars; Accretion; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 October 20; revised 2022 January 6; accepted 2022 January 27; published 2022 March 9. \n\nSupport for this work was provided by NASA through the NASA Hubble Fellowship grant #HST-HF2-51440.001 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (Caltech, USA). \n\nJ.A.G. acknowledges support from NASA grant 80NSSC20K0540 and from the Alexander von Humboldt Foundation. S.G. acknowledges the support of the Centre National d'Etudes Spatiales (CNES).\n\nPublished - Ludlam_2022_ApJ_927_112.pdf
Accepted Version - 2201.11767.pdf
",
"abstract": "We present a spectral analysis of NuSTAR and NICER observations of the luminous, persistently accreting neutron star (NS) low-mass X-ray binary Cygnus X-2. The data were divided into different branches that the source traces out on the Z-track of the X-ray color\u2013color diagram; namely, the horizontal branch, the normal branch, and the vertex between the two. The X-ray continuum spectrum was modeled in two different ways that produced comparable quality fits. The spectra showed clear evidence of a reflection component in the form of a broadened Fe K line, as well as a lower-energy emission feature near 1 keV likely due to an ionized plasma located far from the innermost accretion disk. We account for the reflection spectrum with two independent models (relxillns and rdblur*rfxconv). The inferred inclination is in agreement with earlier estimates from optical observations of ellipsoidal lightcurve modeling (relxillns: i = 67\u00b0 \u00b1 4\u00b0; rdblur*rfxconv: i = 60\u00b0 \u00b1 10\u00b0). The inner disk radius remains close to the NS (R_(in) \u2264 1.15 R_(ISCO)) regardless of the source position along the Z-track or how the 1 keV feature is modeled. Given the optically determined NS mass of 1.71 \u00b1 0.21 M_\u2299, this corresponds to a conservative upper limit of R_(in) \u2264 19.5 km for M = 1.92 M_\u2299 or R_(in) \u2264 15.3 km for M = 1.5 M_\u2299. We compare these radius constraints to those obtained from NS gravitational wave merger events and recent NICER pulsar lightcurve modeling measurements.",
"date": "2022-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "927",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 112",
"id_number": "CaltechAUTHORS:20220309-982137000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220309-982137000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0540"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac5028",
"primary_object": {
"basename": "2201.11767.pdf",
"url": "https://authors.library.caltech.edu/records/3mzv9-ab577/files/2201.11767.pdf"
},
"related_objects": [
{
"basename": "Ludlam_2022_ApJ_927_112.pdf",
"url": "https://authors.library.caltech.edu/records/3mzv9-ab577/files/Ludlam_2022_ApJ_927_112.pdf"
}
],
"pub_year": "2022",
"author_list": "Ludlam, R. M.; Cackett, E. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ywns3-e6t82",
"eprint_id": 113774,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:28:30",
"lastmod": "2026-03-18 04:41:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Drake",
"given": "J. F."
},
"orcid": "0000-0002-9150-1841"
},
{
"name": {
"family": "Phan",
"given": "T."
},
"orcid": "0000-0002-6924-9408"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Joyce",
"given": "C."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "Malandraki",
"given": "O."
},
"orcid": "0000-0002-4751-6835"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Verniero",
"given": "J."
},
"orcid": "0000-0003-1138-652X"
},
{
"name": {
"family": "Rahmati",
"given": "A."
},
"orcid": "0000-0003-0519-6498"
},
{
"name": {
"family": "Whittlesey",
"given": "P."
},
"orcid": "0000-0002-7287-5098"
},
{
"name": {
"family": "Livi",
"given": "R."
},
"orcid": "0000-0002-0396-0547"
},
{
"name": {
"family": "Larson",
"given": "D."
},
"orcid": "0000-0001-5030-6030"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Niehof",
"given": "J. T."
},
"orcid": "0000-0001-6286-5809"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Horbury",
"given": "T. S."
},
"orcid": "0000-0002-7572-4690"
}
]
},
"title": "Suprathermal Ion Energy Spectra and Anisotropies near the Heliospheric Current Sheet Crossing Observed by the Parker Solar Probe during Encounter 7",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "The Sun; Solar magnetic reconnection; Interplanetary particle acceleration; Interplanetary magnetic fields; Heliosphere; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 October 25; revised 2021 December 1; accepted 2021 December 10; published 2022 March 4. \n\nThis work was supported by NASA's Parker Solar Probe Mission, contract NNN06AA01C. We thank all the scientists and engineers who have worked hard to make PSP a successful mission, in particular the engineers, scientists, and administrators who designed and built IS\u2299IS/EPI-Lo, IS\u2299IS/EPI-Hi, FIELDS, and SWEAP instrument suites and support their operations and the scientific analysis of its data. For their contributions to the scientific configuration and instrumental analysis, we owe special thanks to P. Kollmann, J. Peachy, and J. Vandegriff at JHU/APL for EPI-Lo. The IS\u2299IS data are available athttp://spp-isois.sr.unh.edu/data_public/ as well as at the NASA Space Physics Data Facility. Work at SwRI is supported in part under NASA grant Nos. 80NSSC20K1815, 80NSSC18K1446, 80NSSC21K0112, 80NSSC20K1255, and 80NSSC21K0971.\n\nPublished - Desai_2022_ApJ_927_62.pdf
Submitted - 2111.00954.pdf
",
"abstract": "We present observations of \u227310\u2013100 keV nucleon\u207b\u00b9 suprathermal (ST) H, He, O, and Fe ions associated with crossings of the heliospheric current sheet (HCS) at radial distances of <0.1 au from the Sun. Our key findings are as follows: (1) very few heavy ions are detected during the first full crossing, the heavy-ion intensities are reduced during the second partial crossing and peak just after the second crossing; (2) ion arrival times exhibit no velocity dispersion; (3) He pitch-angle distributions track the magnetic field polarity reversal and show up to \u223c10:1 anti-sunward, field-aligned flows and beams closer to the HCS that become nearly isotropic farther from the HCS; (4) the He spectrum steepens either side of the HCS, and the He, O, and Fe spectra exhibit power laws of the form \u223cE\u2212\u207b\u2074\u2013E\u2076; and (5) maximum energies EX increase with the ion's charge-to-mass (Q/M) ratio as E_X/E_H \u221d Q_X/M_X^\u03b4, where \u03b4 \u223c 0.65\u20130.76, assuming that the average Q states are similar to those measured in gradual and impulsive solar energetic particle events at 1 au. The absence of velocity dispersion in combination with strong field-aligned anisotropies closer to the HCS appears to rule out solar flares and near-Sun coronal-mass-ejection-driven shocks. These new observations present challenges not only for mechanisms that employ direct parallel electric fields and organize maximum energies according to E/Q but also for local diffusive and magnetic-reconnection-driven acceleration models. Reevaluation of our current understanding of the production and transport of energetic ions is necessary to understand this near-solar, current-sheet-associated population of ST ions.",
"date": "2022-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "927",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 62",
"id_number": "CaltechAUTHORS:20220307-189632000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220307-189632000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1815"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1446"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0112"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1255"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0971"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4357/ac4961",
"primary_object": {
"basename": "2111.00954.pdf",
"url": "https://authors.library.caltech.edu/records/ywns3-e6t82/files/2111.00954.pdf"
},
"related_objects": [
{
"basename": "Desai_2022_ApJ_927_62.pdf",
"url": "https://authors.library.caltech.edu/records/ywns3-e6t82/files/Desai_2022_ApJ_927_62.pdf"
}
],
"pub_year": "2022",
"author_list": "Desai, M. I.; Mitchell, D. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tc42e-pwf35",
"eprint_id": 113715,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:27:54",
"lastmod": "2025-11-21 00:22:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kamraj-Nikita",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "X-Ray Coronal Properties of Swift/BAT-selected Seyfert 1 Active Galactic Nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; Black holes; X-ray sources; Seyfert galaxies; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 July 20; revised 2021 November 2; accepted 2021 November 20; published 2022 March 3. \n\nWe have made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the following resources: NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA); online Swift data processing services provided by the SSDC; the High Energy Astrophysics Science Archive Research Center Online Service, provided by the NASA/Goddard Space Flight Center; NASA's Astrophysics Data System; Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013, 2018). Some of the optical spectra used for determining black hole masses used in this work were taken with the Doublespec (DBSP) instrument at Palomar via Yale (PI: M. Powell, 2017\u20132019, 16 nights) as well as Caltech (PI: F. Harrison) and JPL (PI: D. Stern) from programs from 2013 to 2020. \n\nM. Balokovi\u0107 acknowledges support from the Black Hole Initiative at Harvard University, which is funded in part by the Gordon and Betty Moore Foundation (grant GBMF8273) and in part by the John Templeton Foundation, as well as support from the YCAA Prize Postdoctoral Fellowship. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). C.R. acknowledges support from the CONICYT+PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift - , XMM-Newton - , Palomar Hale(DBSP). - \n\nSoftware: TBabs (Wilms et al. 2000), pexrav (Magdziarz & Zdziarski 1995), nthComp (Zdziarski et al. 1996), xillverCp (Garc\u00eda & Kallman 2010), NuSTARDAS (v2.17.1), HEASOFT (v6.24), XMM SAS (v16.1.0), XSPEC (v12.8.2), Astropy (Astropy Collaboration et al. 2013, 2018), NumPy, Matplotlib (Hunter 2007).\n\nPublished - Kamraj_2022_ApJ_927_42.pdf
Accepted Version - 2202.00895.pdf
",
"abstract": "The corona is an integral component of active galactic nuclei (AGNs) which produces the bulk of the X-ray emission above 1\u20132 keV. However, many of its physical properties and the mechanisms powering this emission remain a mystery. In particular, the temperature of the coronal plasma has been difficult to constrain for large samples of AGNs, as constraints require high-quality broadband X-ray spectral coverage extending above 10 keV in order to measure the high-energy cutoff, which provides constraints on the combination of coronal optical depth and temperature. We present constraints on the coronal temperature for a large sample of Seyfert 1 AGNs selected from the Swift/BAT survey using high-quality hard X-ray data from the NuSTAR observatory combined with simultaneous soft X-ray data from Swift/XRT or XMM-Newton. When applying a physically motivated, nonrelativistic disk-reflection model to the X-ray spectra, we find a mean coronal temperature kT_e = 84 \u00b1 9 keV. We find no significant correlation between the coronal cutoff energy and accretion parameters such as the Eddington ratio and black hole mass. We also do not find a statistically significant correlation between the X-ray photon index, \u0393, and Eddington ratio. This calls into question the use of such relations to infer properties of supermassive black hole systems.",
"date": "2022-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "927",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 42",
"id_number": "CaltechAUTHORS:20220303-225982929",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220303-225982929",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Harvard University"
},
{
"agency": "Gordon and Betty Moore Foundation",
"grant_number": "GBMF8273"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PAI77170080"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac45f6",
"primary_object": {
"basename": "2202.00895.pdf",
"url": "https://authors.library.caltech.edu/records/tc42e-pwf35/files/2202.00895.pdf"
},
"related_objects": [
{
"basename": "Kamraj_2022_ApJ_927_42.pdf",
"url": "https://authors.library.caltech.edu/records/tc42e-pwf35/files/Kamraj_2022_ApJ_927_42.pdf"
}
],
"pub_year": "2022",
"author_list": "Kamraj, Nikita; Brightman, Murray; et al."
},
{
"id": "https://authors.library.caltech.edu/records/j43v4-yqs79",
"eprint_id": 113536,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:18:47",
"lastmod": "2025-11-20 20:29:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jin-Meng",
"name": {
"family": "Jin",
"given": "Meng"
},
"orcid": "0000-0002-9672-3873"
},
{
"id": "Nitta-Nariaki-V",
"name": {
"family": "Nitta",
"given": "Nariaki V."
},
"orcid": "0000-0001-6119-0221"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina M."
},
"orcid": "0000-0002-0978-8127"
}
]
},
"title": "Assessing the Influence of Input Magnetic Maps on Global Modeling of the Solar Wind and CME-Driven Shock in the 2013 April 11 Event",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Atmospheric Science",
"note": "\u00a9 2022. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 26 February 2022; Version of Record online: 26 February 2022; Accepted manuscript online: 17 February 2022; Manuscript accepted: 11 February 2022; Manuscript revised: 04 February 2022; Manuscript received: 27 August 2021. \n\nWe are very grateful to the referees for invaluable comments that helped improve the paper. We thank Marc DeRosa at LMSAL for the helpful discussion on the LM synchronic magnetic maps. Meng Jin, Nariaki V. Nitta, and Christina M. S. Cohen are supported by NASA HSR grant 80NSSC18K1126. We thank the simulation results were obtained using the Space Weather Modeling Framework (SWMF), developed at the Center for Space Environment Modeling (CSEM), University of Michigan (https://github.com/MSTEM-QUDA/SWMF). We are thankful for the use of the NASA Supercomputer Pleiades at Ames and for its supporting staff for making it possible to perform the simulations presented in this paper. SDO is the first mission of NASA's Living with a Star Program. \n\nData Availability Statement: The LM synchronic magnetic map was downloaded directly from the PFSS package in SSWIDL. The Stanford HMI diachronic magnetic map is accessible at JSOC (http://jsoc.stanford.edu/). The AWSoM and EEGGL models used in this study are available through NASA CCMC (https://ccmc.gsfc.nasa.gov/). The spacecraft location data were downloaded from https://omniweb.gsfc.nasa.gov/coho/helios/heli.html. The simulation data used in this study is available at https://10.5281/zenodo.5787007.\n\nPublished - Space_Weather_-_2022_-_Jin_-_Assessing_the_Influence_of_Input_Magnetic_Maps_on_Global_Modeling_of_the_Solar_Wind_and.pdf
",
"abstract": "In the past decade, significant efforts have been made in developing physics-based solar wind and coronal mass ejection (CME) models, which have been or are being transferred to national centers (e.g., SWPC, Community Coordinated Modeling Center) to enable space weather predictive capability. However, the input data coverage for space weather forecasting is extremely limited. One major limitation is the solar magnetic field measurements, which are used to specify the inner boundary conditions of the global magnetohydrodynamic (MHD) models. In this study, using the Alfv\u00e9n wave solar model, we quantitatively assess the influence of the magnetic field map input (synoptic/diachronic vs. synchronic magnetic maps) on the global modeling of the solar wind and the CME-driven shock in the 11 April 2013 solar energetic particle event. Our study shows that due to the inhomogeneous background solar wind and dynamical evolution of the CME, the CME-driven shock parameters change significantly both spatially and temporally as the CME propagates through the heliosphere. The input magnetic map has a great impact on the shock connectivity and shock properties in the global MHD simulation. Therefore this study illustrates the importance of taking into account the model uncertainty due to the imperfect magnetic field measurements when using the model to provide space weather predictions.",
"date": "2022-03",
"date_type": "published",
"publication": "Space Weather",
"volume": "20",
"number": "3",
"publisher": "American Geophysical Union",
"pagerange": "Art. No. e2021SW002894",
"id_number": "CaltechAUTHORS:20220222-707155000",
"issn": "1542-7390",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220222-707155000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC18K1126"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1029/2021sw002894",
"primary_object": {
"basename": "Space_Weather_-_2022_-_Jin_-_Assessing_the_Influence_of_Input_Magnetic_Maps_on_Global_Modeling_of_the_Solar_Wind_and.pdf",
"url": "https://authors.library.caltech.edu/records/j43v4-yqs79/files/Space_Weather_-_2022_-_Jin_-_Assessing_the_Influence_of_Input_Magnetic_Maps_on_Global_Modeling_of_the_Solar_Wind_and.pdf"
},
"pub_year": "2022",
"author_list": "Jin, Meng; Nitta, Nariaki V.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/m4x3e-91c36",
"eprint_id": 113617,
"eprint_status": "archive",
"datestamp": "2023-08-22 14:05:27",
"lastmod": "2025-11-20 21:45:14",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "McKinley C."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "Douglas J. K."
},
"orcid": "0000-0002-5341-6929"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley"
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Krivonos-Roman-A",
"name": {
"family": "Krivonos",
"given": "Roman"
},
"orcid": "0000-0003-2737-5673"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "Renee"
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Wik-Daniel",
"name": {
"family": "Wik",
"given": "Daniel"
},
"orcid": "0000-0001-9110-2245"
}
]
},
"title": "Extending the Baseline for SMC X-1's Spin and Orbital Behavior with NuSTAR Stray Light",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray binary stars; High mass x-ray binary stars; Pulsars; Neutron stars; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 November 12; revised 2022 January 6; accepted 2022 January 17; published 2022 February 24. \n\nThe authors thank the anonymous referee for their time in reading the manuscript and providing helpful comments. M.C.B. would like to thank J. Thorstensen for communication about calculating orbital ephemerides and acknowledges support from NASA funding award No. 80NSSC21K0263. R.K. acknowledges support from the Russian Science Foundation grant 19-12-00369. R.L. acknowledges the support of NASA through the Hubble Fellowship Program grant HST-HF2-51440.001. \n\nSoftware: HEAsoft (v6.29c; HEASARC 2014), NuSTARDAS, Stingray (Huppenkothen et al. 2019), HENDRICS (Bachetti 2018), MaLTPyNT (Bachetti 2015), nustar-gen-utils.\n\nPublished - Brumback_2022_ApJ_926_187.pdf
Accepted Version - 2202.11261.pdf
",
"abstract": "StrayCats, the catalog of NuSTAR stray light observations, contains data from bright X-ray sources that fall within crowded source regions. These observations offer unique additional data with which to monitor sources such as X-ray binaries that show variable timing behavior. In this work, we present a timing analysis of stray light data of the high-mass X-ray binary SMC X-1, the first scientific analysis of a single source from the StrayCats project. We describe the process of screening stray light data for scientific analysis, verify the orbital ephemeris, and create both time- and energy-resolved pulse profiles. We find that the orbital ephemeris of SMC X-1 is unchanged and confirm a long-term spin-up rate of \u03bd \u0307 = (2.52 \u00b1 0.03) \u00d7 10\u207b\u00b9\u00b9 Hz s\u207b\u00b9. We also note that the shape of SMC X-1's pulse profile, while remaining double peaked, varies significantly with time and only slightly with energy.",
"date": "2022-02-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "926",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 187",
"id_number": "CaltechAUTHORS:20220225-724712000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220225-724712000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC21K0263"
},
{
"agency": "Russian Science Foundation",
"grant_number": "19-12-00369"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA Einstein Fellowship"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac4d24",
"primary_object": {
"basename": "2202.11261.pdf",
"url": "https://authors.library.caltech.edu/records/m4x3e-91c36/files/2202.11261.pdf"
},
"related_objects": [
{
"basename": "Brumback_2022_ApJ_926_187.pdf",
"url": "https://authors.library.caltech.edu/records/m4x3e-91c36/files/Brumback_2022_ApJ_926_187.pdf"
}
],
"pub_year": "2022",
"author_list": "Brumback, McKinley C.; Grefenstette, Brian W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z7eth-f1r13",
"eprint_id": 112879,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:56:05",
"lastmod": "2025-11-20 22:48:25",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "Renee"
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "Michael"
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "Relativistic X-Ray Reflection Models for Accreting Neutron Stars",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Relativistic disks; Atomic physics; Atomic spectroscopy; Neutron stars; X-ray astronomy; X-ray transient sources; Spectral line lists",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 March 11; revised 2021 November 17; accepted 2021 November 22; published 2022 February 8. \n\nWe thank the referee for thoughtful comments that greatly improved this paper. We also thank E. Kara, D. Barret, and E. Kammoun for clarifications regarding the simulations with XRISM and Athena instrumental responses. J.A.G. acknowledges support from NASA ATP grant 80NSSC20K0540 and from the Alexander von Humboldt Foundation. R.M.L. acknowledges the support of NASA through the Hubble Fellowship Program grant HST-HF2-51440.001. This work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacility: NuSTAR. - \n\nSoftware: xspec (v12.10.0c; Arnaud 1996), xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), relxill (v1.5.0; Garc\u00eda et al. 2014; Dauser et al. 2014).\n\nPublished - Garc\u00eda_2022_ApJ_926_13.pdf
Accepted Version - 2111.12838.pdf
",
"abstract": "We present new reflection models specifically tailored to model the X-ray radiation reprocessed in accretion disks around neutron stars, in which the primary continuum is characterized by a single-temperature blackbody spectrum, emitted either at the surface of the star or at the boundary layer. These models differ significantly from those with a standard power-law continuum, typically observed in most accreting black holes. We show comparisons with earlier reflection models and test their performance in the NuSTAR observation of the neutron star 4U 1705\u221244. Simulations of upcoming missions such as XRISM-Resolve and Athena X-IFU are shown to highlight the diagnostic potential of these models for high-resolution X-ray reflection spectroscopy. These new reflection models xillverNS, and their relativistic counterpart relxillNS, are made publicly available to the community as an additional flavor in the relxill suite of reflection models.",
"date": "2022-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "926",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 13",
"id_number": "CaltechAUTHORS:20220113-182247899",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182247899",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K0540"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Einstein Fellowship"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac3cb7",
"primary_object": {
"basename": "2111.12838.pdf",
"url": "https://authors.library.caltech.edu/records/z7eth-f1r13/files/2111.12838.pdf"
},
"related_objects": [
{
"basename": "Garc\u00eda_2022_ApJ_926_13.pdf",
"url": "https://authors.library.caltech.edu/records/z7eth-f1r13/files/Garc\u00eda_2022_ApJ_926_13.pdf"
}
],
"pub_year": "2022",
"author_list": "Garc\u00eda, Javier A.; Dauser, Thomas; et al."
},
{
"id": "https://authors.library.caltech.edu/records/wwdnn-see50",
"eprint_id": 113821,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:51:43",
"lastmod": "2025-11-21 03:54:55",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Getachew-Tibebu",
"name": {
"family": "Getachew",
"given": "T."
},
"orcid": "0000-0003-2408-4619"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Palmerio-Erika",
"name": {
"family": "Palmerio",
"given": "E."
},
"orcid": "0000-0001-6590-3479"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Matthaeus-William-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Mitchell-John-Grant",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Roelof-Edmond-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Zank-Gary-P",
"name": {
"family": "Zank",
"given": "G. P."
},
"orcid": "0000-0002-4642-6192"
},
{
"id": "Zhao-Lingling",
"name": {
"family": "Zhao",
"given": "L.-L."
},
"orcid": "0000-0002-4299-0490"
},
{
"id": "Lynch-Benjamin-J",
"name": {
"family": "Lynch",
"given": "B. J."
},
"orcid": "0000-0001-6886-855X"
},
{
"id": "Phan-Tai-D",
"name": {
"family": "Phan",
"given": "T. D."
},
"orcid": "0000-0002-6924-9408"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Whittlesey-Phyllis-L",
"name": {
"family": "Whittlesey",
"given": "P. L."
},
"orcid": "0000-0002-7287-5098"
},
{
"id": "Kasper-Justin-C",
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
}
]
},
"title": "PSP/IS\u2299IS Observation of a Solar Energetic Particle Event Associated with a Streamer Blowout Coronal Mass Ejection during Encounter 6",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar coronal mass ejections; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 November 10; revised 2021 December 1; accepted 2021 December 3; published 2022 February 7. \n\nThis work was supported as a part of the Integrated Science Investigations of the Sun on NASA's Parker Solar Probe mission, under contract No. NNN06AA01C. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract No. NNN06AA01C). Simulation results have been provided by the Community Coordinated Modeling Center at Goddard Space Flight Center through their public Runs on Request system (http://ccmc.gsfc.nasa.gov). The WSA model was developed by C. N. Arge (currently at NASA/GSFC), and the ENLIL model was developed by D. Odstrcil (currently at GMU). We thank the STEREO team for making the SECCHI data used in this study publicly available. E.P.'s research was supported by the NASA LWS Jack Eddy Postdoctoral Fellowship Program, administered by UCAR's Cooperative Programs for the Advancement of Earth System Science (CPAESS) under award No. NNX16AK22G. B.J.L. acknowledges NASA HGI 80NSSC21K0731, NASA LWS 80NSSC21K1325, and NSF AGS 1851945. T.G.'s work was partially supported by the NASA Heliophysics competed Internal Scientist Funding Model.\n\nPublished - Getachew_2022_ApJ_925_212.pdf
Accepted Version - 2112.04671.pdf
",
"abstract": "In this paper we examine a low-energy solar energetic particle (SEP) event observed by IS\u2299IS's Energetic Particle Instrument-Low (EPI-Lo) inside 0.18 au on 2020 September 30. This small SEP event has a very interesting time profile and ion composition. Our results show that the maximum energy and peak in intensity are observed mainly along the open radial magnetic field. The event shows velocity dispersion, and strong particle anisotropies are observed throughout the event, showing that more particles are streaming outward from the Sun. We do not see a shock in the in situ plasma or magnetic field data throughout the event. Heavy ions, such as O and Fe, were detected in addition to protons and 4He, but without significant enhancements in 3He or energetic electrons. Our analysis shows that this event is associated with a slow streamer blowout coronal mass ejection (SBO-CME), and the signatures of this small CME event are consistent with those typical of larger CME events. The time\u2013intensity profile of this event shows that the Parker Solar Probe encountered the western flank of the SBO-CME. The anisotropic and dispersive nature of this event in a shockless local plasma gives indications that these particles are most likely accelerated remotely near the Sun by a weak shock or compression wave ahead of the SBO-CME. This event may represent direct observations of the source of the low-energy SEP seed particle population.",
"date": "2022-02-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "925",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 212",
"id_number": "CaltechAUTHORS:20220309-676494000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220309-676494000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA Postdoctoral Program",
"grant_number": "NNX16AK22G"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0731"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1325"
},
{
"agency": "NSF",
"grant_number": "AGS-1851945"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac408f",
"primary_object": {
"basename": "2112.04671.pdf",
"url": "https://authors.library.caltech.edu/records/wwdnn-see50/files/2112.04671.pdf"
},
"related_objects": [
{
"basename": "Getachew_2022_ApJ_925_212.pdf",
"url": "https://authors.library.caltech.edu/records/wwdnn-see50/files/Getachew_2022_ApJ_925_212.pdf"
}
],
"pub_year": "2022",
"author_list": "Getachew, T.; McComas, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/x2qp3-grz40",
"eprint_id": 113056,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:25:23",
"lastmod": "2025-11-21 01:42:29",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Strauss-Roelf-D",
"name": {
"family": "Strauss",
"given": "R. D."
},
"orcid": "0000-0002-0205-0808"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Anomalous Cosmic-Ray Oxygen Observations into 0.1 au",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galactic cosmic rays; Cosmic rays; Solar cycle; Oxygen burning; Solar magnetic fields; Solar physics; Solar wind; Particle astrophysics; Space plasmas; Heliosphere; Quiet sun; Interplanetary turbulence; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 September 16; revised 2021 October 23; accepted 2021 October 26; published 2022 January 20. \n\nThis work was supported as a part of the Integrated Science Investigation of the Sun on NASA's Parker Solar Probe mission, under contract NNN06AA01C. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We thank all the scientists and engineers who have worked hard to make PSP a successful mission. We also acknowledge the support provided by Michigan State University's National Superconducting Cyclotron Laboratory, Texas A&M University's Cyclotron Institute, and the Lawrence Berkeley National Laboratory's 88-inch Cyclotron Laboratory during EPI-Hi's calibration and testing.\n\nPublished - Rankin_2022_ApJ_925_9.pdf
Submitted - 2110.03601.pdf
",
"abstract": "The Integrated Science Investigation of the Sun instrument suite onboard NASA's Parker Solar Probe mission continues to measure solar energetic particles and cosmic rays closer to the Sun than ever before. Here, we present the first observations of cosmic rays into 0.1 au (21.5 solar radii), focusing specifically on oxygen from \u223c2018.7 to \u223c2021.2. Our energy spectra reveal an anomalous cosmic-ray-dominated profile that is comparable to that at 1 au, across multiple solar cycle minima. The galactic cosmic-ray-dominated component is similar to that of the previous solar minimum (Solar Cycle 24/25 compared to 23/24) but elevated compared to the past (Solar Cycle 20/21). The findings are generally consistent with the current trend of unusually weak solar modulation that originated during the previous solar minimum and continues today. We also find a strong radial intensity gradient: 49.4 \u00b1 8.0% au\u207b\u00b9 from 0.1 to 0.94 au, for energies of 6.9\u201327 MeV nuc\u207b\u00b9. This value agrees with that measured by Helios nearly 45 yr ago from 0.3 to 1.0 au (48% \u00b1 12% au\u207b\u00b9; 9\u201329 MeV nuc\u207b\u00b9) and is larger than predicted by models. The large anomalous cosmic-ray gradients observed close to the Sun by the Parker Solar Probe Integrated Science Investigation of the Sun instrument suite found here suggest that intermediate-scale variations in the magnetic field's structure strongly influence cosmic-ray drifts, well inside 1 au.",
"date": "2022-01-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "925",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 9",
"id_number": "CaltechAUTHORS:20220121-870753000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220121-870753000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac348f",
"primary_object": {
"basename": "2110.03601.pdf",
"url": "https://authors.library.caltech.edu/records/x2qp3-grz40/files/2110.03601.pdf"
},
"related_objects": [
{
"basename": "Rankin_2022_ApJ_925_9.pdf",
"url": "https://authors.library.caltech.edu/records/x2qp3-grz40/files/Rankin_2022_ApJ_925_9.pdf"
}
],
"pub_year": "2022",
"author_list": "Rankin, J. S.; McComas, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6h7g1-wq892",
"eprint_id": 113088,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:25:34",
"lastmod": "2025-11-21 02:27:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah"
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Israel-Gian-Luca",
"name": {
"family": "Israel",
"given": "Gian Luca"
},
"orcid": "0000-0001-5480-6438"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean"
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Evolution of the Spin, Spectrum and Superorbital Period of the Ultraluminous X-Ray Pulsar M51 ULX7",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "High mass x-ray binary stars; Ultraluminous x-ray sources; Pulsars; Neutron stars; Accretion; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 July 23; revised 2021 November 8; accepted 2021 November 8; published 2022 January 21. \n\nWe thank the referee for their thorough review of our paper which improved it. \n\nThis work was also supported under NASA Contract No. NNG08FD60C. NuSTAR is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nThis work was also based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. \n\nWe wish to thank the Swift P.I., Brad Cenko, for approving the target of opportunity requests we made to observe M51, as well as the rest of the Swift team for carrying them out. We also acknowledge the use of public data from the Swift data archive. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. \n\nThis research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. \n\nG.L.I. acknowledges funding from the Italian MIUR PRIN grant No. 2017LJ39LM. The work of D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. D.J.W. acknowledges support from an STFC Ernest Rutherford Fellowship. \n\nFacilities: Swift(XRT) - Swift Gamma-Ray Burst Mission, NuSTAR - , XMM-Newton. - \n\nSoftware: NuSTARDAS, XMMSAS (Gabriel et al. 2004), XSPEC (Arnaud 1996), hendrics (Bachetti 2015).\n\nPublished - Brightman_2022_ApJ_925_18.pdf
Accepted Version - 2111.05342.pdf
",
"abstract": "M51 ULX7 is among a small group of known ultraluminous X-ray pulsars (ULXPs). The neutron star powering the source has a spin period of 2.8 s, orbits its companion star with a period of 2 days, and a superorbital period of 38 days is evident in its X-ray lightcurve. Here we present NuSTAR and XMM-Newton data on the source from 2019 obtained when the source was near its peak brightness. We detect the pulsations, having spun up at a rate of 3 \u00b1 0.5 \u00d7 10\u207b\u00b9\u2070 s s\u207b\u00b9 since they were previously detected in 2018. The data also provide the first high-quality broadband spectrum of the source. We find it to be very similar to that of other ULXPs, with two disk-like components, and a high-energy tail. When combined with XMM-Newton data obtained in 2018, we explore the evolution of the spectral components with superorbital phase, finding that the luminosity of the hotter component drives the superorbital flux modulation. The inclination the disk components appear to change with phase, which may support the idea that these superorbital periods are caused by disk precession. We also reexamine the superorbital period with 3 yr of Swift/XRT monitoring, finding that the period is variable, increasing from 38.2 \u00b1 0.5 days in 2018\u20132019 to 44.2 \u00b1 0.9 days in 2020\u20132021, which rules out alternative explanations for the superorbital period.",
"date": "2022-01-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "925",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 18",
"id_number": "CaltechAUTHORS:20220124-215321000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220124-215321000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR)",
"grant_number": "2017LJ39LM"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac3829",
"primary_object": {
"basename": "2111.05342.pdf",
"url": "https://authors.library.caltech.edu/records/6h7g1-wq892/files/2111.05342.pdf"
},
"related_objects": [
{
"basename": "Brightman_2022_ApJ_925_18.pdf",
"url": "https://authors.library.caltech.edu/records/6h7g1-wq892/files/Brightman_2022_ApJ_925_18.pdf"
}
],
"pub_year": "2022",
"author_list": "Brightman, Murray; Bachetti, Matteo; et al."
},
{
"id": "https://authors.library.caltech.edu/records/rqg6n-rqr66",
"eprint_id": 113013,
"eprint_status": "archive",
"datestamp": "2023-09-15 07:27:03",
"lastmod": "2025-11-20 20:32:10",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ananna-Tonima-Tasnim",
"name": {
"family": "Ananna",
"given": "Tonima Tasnim"
},
"orcid": "0000-0001-8211-3807"
},
{
"id": "Weigel-Anna-K",
"name": {
"family": "Weigel",
"given": "Anna K."
},
"orcid": "0000-0002-5489-4316"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Hickox-Ryan-C",
"name": {
"family": "Hickox",
"given": "Ryan C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Ueda-Yoshihiro",
"name": {
"family": "Ueda",
"given": "Yoshihiro"
},
"orcid": "0000-0001-7821-6715"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Ricci-Federica",
"name": {
"family": "Ricci",
"given": "Federica"
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Mej\u00eda-Restrepo-Julian-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Julian E."
}
},
{
"id": "den-Brok-Jakob-S",
"name": {
"family": "den Brok",
"given": "Jakob"
},
"orcid": "0000-0002-8760-6157"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Caglar-Turgay",
"name": {
"family": "Caglar",
"given": "Turgay"
}
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Wong-O-Ivy",
"name": {
"family": "Wong",
"given": "O. Ivy"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
}
]
},
"title": "BASS XXX: Distribution Functions of DR2 Eddington-ratios, Black Hole Masses, and X-ray Luminosities",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank the anonymous reviewers for their constructive comments which helped us improve the quality of this paper. T.T.A. and R.C.H. acknowledge support from NASA through ADAP award 80NSSC19K0580, and the National Science Foundation through CAREER award 1554584. B.T. acknowledges support from the Israel Science Foundation (grant number 1849/19) and from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement number 950533). M.K. acknowledges support from NASA through ADAP award NNH16CT03C. C.M.U. acknowledges support from the National Science Foundation under Grant No. AST-1715512. C.R. acknowledges support from the Fondecyt Iniciacion grant 11190831. We acknowledge support from ANID-Chile Basal AFB-170002 and FB210003 (E.T., F.E.B.), FONDECYT Regular 1200495 and 1190818 (E.T., F.E.B.), ANID Anillo ACT172033 (E.T.), Millennium Nucleus NCN19 058 (TITANs; E.T.) and Millennium Science Initiative Program - ICN12 009 (F.E.B.). K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). The work of K.I. is supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (18K13584, 20H01939). \n\nThis work was performed in part at Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. \n\nThis research made use of Astropy (Astropy Collaboration et al. 2013; Price-Whelan et al. 2018), Matplotlib (Hunter 2007), Emcee (Foreman-Mackey et al. 2013), NumPy (van der Walt et al. 2011), Topcat (Taylor 2005), xpec and pyxpsec (Arnaud 1996), and ChainConsumer (Hinton 2016).\n\nSubmitted - 2201.05603.pdf
",
"abstract": "We determine the low-redshift X-ray luminosity function (XLF), active black hole mass function (BHMF), and Eddington-ratio distribution function (ERDF) for both unobscured (Type 1) and obscured (Type 2) active galactic nuclei (AGN) using the unprecedented spectroscopic completeness of the BAT AGN Spectroscopic Survey (BASS) data release 2. In addition to a straightforward 1/Vmax approach, we also compute the intrinsic distributions, accounting for sample truncation by employing a forward modeling approach to recover the observed BHMF and ERDF. As previous BHMFs and ERDFs have been robustly determined only for samples of bright, broad-line (Type 1) AGNs and/or quasars, ours is the first directly observationally constrained BHMF and ERDF of Type 2 AGN. We find that after accounting for all observational biases, the intrinsic ERDF of Type 2 AGN is significantly skewed towards lower Eddington ratios than the intrinsic ERDF of Type 1 AGN. This result supports the radiation-regulated unification scenario, in which radiation pressure dictates the geometry of the dusty obscuring structure around an AGN. Calculating the ERDFs in two separate mass bins, we verify that the derived shape is consistent, validating the assumption that the ERDF (shape) is mass independent. We report the local AGN duty cycle as a function of mass and Eddington ratio, by comparing the BASS active BHMF with the local mass function for all SMBH. We also present the log N-log S of Swift-BAT 70-month sources.",
"date": "2022-01-14",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20220119-234014000",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220119-234014000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K0580"
},
{
"agency": "NSF",
"grant_number": "AST-1554584"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "950533"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "NSF",
"grant_number": "AST-1715512"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "FB210003"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "ACT172033"
},
{
"agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)",
"grant_number": "NCN19_058"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "18K13584"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "20H01939"
},
{
"agency": "NSF",
"grant_number": "PHY-1607611"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.2201.05603",
"primary_object": {
"basename": "2201.05603.pdf",
"url": "https://authors.library.caltech.edu/records/rqg6n-rqr66/files/2201.05603.pdf"
},
"pub_year": "2022",
"author_list": "Ananna, Tonima Tasnim; Weigel, Anna K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6vye8-zy266",
"eprint_id": 112849,
"eprint_status": "archive",
"datestamp": "2023-09-15 07:22:46",
"lastmod": "2025-11-20 21:00:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Roussos-Elias",
"name": {
"family": "Roussos",
"given": "Elias"
},
"orcid": "0000-0002-5699-0678"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina"
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Kollmann-Peter",
"name": {
"family": "Kollmann",
"given": "Peter"
}
},
{
"id": "Pinto-Marco",
"name": {
"family": "Pinto",
"given": "Marco"
}
},
{
"id": "Krupp-Norbert",
"name": {
"family": "Krupp",
"given": "Norbert"
}
},
{
"id": "Gon\u00e7alves-Patricia",
"name": {
"family": "Gon\u00e7alves",
"given": "Patricia"
}
},
{
"id": "Dialynas-Konstantinos",
"name": {
"family": "Dialynas",
"given": "Konstantinos"
},
"orcid": "0000-0002-5231-7929"
}
]
},
"title": "A source of very energetic oxygen located in Jupiter's inner radiation belts",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). \n\nSubmitted 17 September 2021; Accepted 19 November 2021; Published 12 January 2022.\n\nWe acknowledge support by the PDS through which the HIC data were obtained and R. Wilson (LASP, USA) and R. Selesnick (Air Force Research Laboratory, USA) for assistance in reconstructing the HIC pointing. We are thankful to the GEANT4 collaboration and J. F. Ziegler for making available the GEANT4 and SRIM packages that were used to simulate HIC responses and ring spallation. \n\nE.R. and N.K. are supported by the German Space Agency (DLR) through contract 50 QJ 1503 and by the Max Planck Society. \n\nAuthor contributions: All authors contributed to the discussion and interpretation of the data and the writing of the manuscript. E.R. developed the study concept and performed most data analysis tasks, including simulations of the HIC sensor responses. C.C. contributed to the evaluation and interpretation of the PDS-archived data of HIC. P.K. provided software for the range-energy analysis of HIC responses, generated the processed EPD/CMS data, and performed the magnetic mapping of Galileo measurements. M.P. performed GEANT4 simulations of ring spallation. K.D. contributed to the analysis of HIC and EPD spectra. N.K. and P.G. administered the project on the side of MPS and LIP, respectively. \n\nThe authors declare that they have no competing interests. \n\nData and materials availability: All HIC data used in the present study are available through NASA's PDS at https://pds-ppi.igpp.ucla.edu/search/?sc=Galileo&t=Jupiter&i=HIC. Processed Galileo EPD/CMS data are available at sd-www.jhuapl.edu/Galileo_EPD/. The processing steps of these datasets and caveats of the archived datasets are described in Materials and Methods.\n\nPublished - sciadv.abm4234.pdf
Supplemental Material - sciadv.abm4234_sm.pdf
",
"abstract": "Jupiter hosts the most hazardous radiation belts of our solar system that, besides electrons and protons, trap an undetermined mix of heavy ions. The details of this mix are critical to resolve because they can reveal the role of Jupiter's moons relative to other less explored energetic ion sources. Here, we show that with increasing energy and in the vicinity of Jupiter's moon Amalthea, the belts' ion composition transitions from sulfur- to oxygen-dominated due to a local source of \u227350 MeV/nucleon oxygen. Contrary to Earth's and Saturn's radiation belts, where their most energetic ions are supplied through atmospheric and ring interactions with externally accelerated cosmic rays, Jupiter's magnetosphere powers this oxygen source internally. The underlying source mechanism, involving either Jovian ring spallation by magnetospheric sulfur or stochastic oxygen heating by low-frequency plasma waves, puts Jupiter's ion radiation belt in the same league with that of astrophysical particle accelerators.",
"date": "2022-01-12",
"date_type": "published",
"publication": "Science Advances",
"volume": "8",
"number": "2",
"publisher": "American Association for the Advancement of Science",
"pagerange": "Art. No. abm4234",
"id_number": "CaltechAUTHORS:20220112-204842129",
"issn": "2375-2548",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220112-204842129",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50 QJ 1503"
},
{
"agency": "Max Planck Society"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1126/sciadv.abm4234",
"primary_object": {
"basename": "sciadv.abm4234_sm.pdf",
"url": "https://authors.library.caltech.edu/records/6vye8-zy266/files/sciadv.abm4234_sm.pdf"
},
"related_objects": [
{
"basename": "sciadv.abm4234.pdf",
"url": "https://authors.library.caltech.edu/records/6vye8-zy266/files/sciadv.abm4234.pdf"
}
],
"pub_year": "2022",
"author_list": "Roussos, Elias; Cohen, Christina; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ascr6-4sq38",
"eprint_id": 112990,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:19:44",
"lastmod": "2025-11-21 03:06:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Guo-Fan",
"name": {
"family": "Guo",
"given": "Fan"
},
"orcid": "0000-0003-4315-3755"
},
{
"id": "Zhao-Lulu",
"name": {
"family": "Zhao",
"given": "Lulu"
},
"orcid": "0000-0003-3936-5288"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "Joe"
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Kahler-Stephen-W",
"name": {
"family": "Kahler",
"given": "S. W."
},
"orcid": "0000-0002-0470-7236"
},
{
"id": "Li-Xiaocan",
"name": {
"family": "Li",
"given": "Xiaocan"
},
"orcid": "0000-0001-5278-8029"
},
{
"id": "Zhang-Qile",
"name": {
"family": "Zhang",
"given": "Qile"
},
"orcid": "0000-0002-9504-641X"
},
{
"id": "Ho-George-C",
"name": {
"family": "Ho",
"given": "George C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "Mihir I."
},
"orcid": "0000-0002-7318-6008"
}
]
},
"title": "Variable Ion Compositions of Solar Energetic Particle Events in the Inner Heliosphere: A Field Line Braiding Model with Compound Injections",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 July 25; revised 2021 October 9; accepted 2021 October 20; published 2022 January 6. \n\nWe acknowledge the constructive comments from the reviewer of this paper, which significantly helped improve the clarity of the paper. We thank members of SolFER collaboration for helpful feedback. SolFER is a multi-institutional collaboration for understanding the release of magnetic field energy and associated particle acceleration in flares in the solar corona. F.G., C.M.S.C., M.W., and Q.Z. acknowledge SolFER DRIVE center program with grant number 80NSSC20K0627 and 80HQTR20T0040. F.G. and L.Z. acknowledge support from NASA PSP GI Program 80HQTR21T0117. F.G. and J.G. acknowledge support in part from NASA LWS Program grant 80HQTR21T0005. L.Z. is supported in part by NASA SOLSTICE DRIVE Science Center grant 80NSSC20K0600 and NASA LWS grant 80NSSC21K0417. The work by X.L. and F.G. is funded in part by NASA grant 80NSSC21K1313 and 80HQTR21T0087. The work of C.M.S.C., J.G., R.A.L., M.E.W., and M.D. was supported in part by NASA's Parker Solar Probe Mission under contract NNN06AA01C. J.G. also acknowledges NASA under grant 80NSSC20K1283, and NSF/AGS under grant1931252. Q.Z. also acknowledges support from NASA grant 80HQTR21T0103. F.G. is also supported by DOE through the LDRD program at LANL and office of Fusion Energy Sciences.\n\nPublished - Guo_2022_ApJ_924_22.pdf
Accepted Version - 2110.10880.pdf
",
"abstract": "We propose a model for interpreting highly variable ion composition ratios in solar energetic particle (SEP) events recently observed by the Parker Solar Probe (PSP) at 0.3\u20130.45 au. We use numerical simulations to calculate SEP propagation in a turbulent interplanetary magnetic field with a Kolmogorov power spectrum from large scales down to the gyration scale of energetic particles. We show that when the source regions of different species are offset by a distance comparable to the size of the source regions, the observed energetic particle composition He/H can be strongly variable over more than two orders of magnitude, even if the source ratio is at the nominal value. Assuming a \u00b3He/\u2074He source ratio of 10% in impulsive \u00b3He-rich events and the same spatial offset of the source regions, the \u00b3He/\u2074He ratio at observation sites also vary considerably. The variability of the ion composition ratios depends on the radial distance, which can be tested by observations made at different radial locations. We discuss the implications of these results on the variability of ion composition of impulsive events and on further PSP and Solar Orbiter observations close to the Sun.",
"date": "2022-01-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "924",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 22",
"id_number": "CaltechAUTHORS:20220119-572574000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220119-572574000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K0627"
},
{
"agency": "NASA",
"grant_number": "80HQTR20T0040"
},
{
"agency": "NASA",
"grant_number": "80HQTR21T0117"
},
{
"agency": "NASA",
"grant_number": "80HQTR21T0005"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0600"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0417"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K1313"
},
{
"agency": "NASA",
"grant_number": "80HQTR21T0087"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1283"
},
{
"agency": "NSF",
"grant_number": "AGS-1931252"
},
{
"agency": "NASA",
"grant_number": "80HQTR21T0103"
},
{
"agency": "Los Alamos National Laboratory"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac3233",
"primary_object": {
"basename": "2110.10880.pdf",
"url": "https://authors.library.caltech.edu/records/ascr6-4sq38/files/2110.10880.pdf"
},
"related_objects": [
{
"basename": "Guo_2022_ApJ_924_22.pdf",
"url": "https://authors.library.caltech.edu/records/ascr6-4sq38/files/Guo_2022_ApJ_924_22.pdf"
}
],
"pub_year": "2022",
"author_list": "Guo, Fan; Zhao, Lulu; et al."
},
{
"id": "https://authors.library.caltech.edu/records/83erc-a5496",
"eprint_id": 113665,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:12:54",
"lastmod": "2025-06-30 18:35:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Zoglauer-Andreas",
"name": {
"family": "Zoglauer",
"given": "Andreas"
},
"orcid": "0000-0001-9067-3150"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Reconstruction of the NuSTAR point spread function using single-laser metrology",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "laser metrology; space telescopes; point spread functions; x-rays; Space and Planetary Science; Mechanical Engineering; Astronomy and Astrophysics; Instrumentation; Control and Systems Engineering; Electronic, Optical and Magnetic Materials",
"note": "\u00a9 2022 The Authors. Published by SPIE under a Creative Commons Attribution 4.0 International License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. \n\nPaper 21127 received Oct. 7, 2021; accepted for publication Feb. 8, 2022; published online Feb.\n22, 2022.\n\nWe thank our anonymous reviewers for helpful comments that improved this paper. This work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology.\n\nPublished - 014009_1.pdf
Accepted Version - 2202.04685.pdf
",
"abstract": "We describe a method by which the metrology system of the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray space observatory, which uses two lasers to characterize the relative motion of the optics and focal plane benches, can be approximated should one laser fail. The two benches are separated by a 10-m-long rigid mast that undergoes small amounts of thermal flexing that needs to be compensated for to produce a nonblurred image. We analyze the trends of mast motion by archival observation parameters to discover whether the mast motion in future observations can be predicted. We find that, using the solar aspect angle, observation date, and orbital phase, we can simulate the motion of one laser by translating the track produced by the other and applying modifications to the resulting mast aspect solution, allowing for the reconstruction of a minimally distorted point spread function in most cases. We will implement the generation of simulated mast files along with the usual NuSTAR data reduction pipeline for contingency purposes. This work has implications for reducing the risk of implementing laser metrology systems on future missions that use deployable masts to achieve the long focal lengths required in high-energy astronomy by mitigating the impact of a metrology laser failure in the extended phase of a mission.",
"date": "2022-01",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "8",
"number": "1",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"pagerange": "Art. No. 014009",
"id_number": "CaltechAUTHORS:20220301-900015000",
"issn": "2329-4124",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220301-900015000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1117/1.jatis.8.1.014009",
"primary_object": {
"basename": "014009_1.pdf",
"url": "https://authors.library.caltech.edu/records/83erc-a5496/files/014009_1.pdf"
},
"related_objects": [
{
"basename": "2202.04685.pdf",
"url": "https://authors.library.caltech.edu/records/83erc-a5496/files/2202.04685.pdf"
}
],
"pub_year": "2022",
"author_list": "Earnshaw, Hannah P.; Madsen, Kristin K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9dcsw-at394",
"eprint_id": 112308,
"eprint_status": "archive",
"datestamp": "2023-08-22 13:02:44",
"lastmod": "2023-10-23 21:01:20",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Feng-Ye",
"name": {
"family": "Feng",
"given": "Ye"
}
},
{
"id": "Zhao-Xueshan",
"name": {
"family": "Zhao",
"given": "XueShan"
}
},
{
"id": "Gou-Lijun",
"name": {
"family": "Gou",
"given": "LiJun"
}
},
{
"id": "Liu-Yufeng",
"name": {
"family": "Liu",
"given": "YuFeng"
},
"orcid": "0000-0002-1686-0545"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Wang-Yuan",
"name": {
"family": "Wang",
"given": "Yuan"
}
},
{
"id": "Jia-Nan",
"name": {
"family": "Jia",
"given": "Nan"
}
},
{
"id": "Liao-ZhenXuan",
"name": {
"family": "Liao",
"given": "ZhenXuan"
}
},
{
"id": "Li-Huixian",
"name": {
"family": "Li",
"given": "HuiXian"
}
}
]
},
"title": "Spectral analysis of new black hole candidate AT2019wey observed by NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "NuSTAR, black hole physics, X-rays, binaries-stars, individual, AT2019we; General Physics and Astronomy",
"note": "c Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2021. \n\nReceived August 15, 2021; accepted September 16, 2021; published online November 24, 2021. \n\nYe Feng thanks the useful discussions with Prof. Mihoko Yukita on extracting NuSTAR spectrum. Ye Feng also thanks the useful discussions with Yunfeng Chen. The software used is provided by the High Energy Astrophysics Science Archive Research Centre (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (Caltech, USA). LiJun Gou is supported by the National Program on Key Research and Development Project (Grant No. 2016YFA0400804), the National Natural Science Foundation of China (Grant No. U1838114), and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB23040100).\n\nAccepted Version - 2109.07357.pdf
",
"abstract": "AT2019wey is a new galactic X-ray binary that was first discovered as an optical transient by the Australia Telescope Large Area Survey (ATLAS) on December 7, 2019. AT2019wey consists of a black hole candidate as well as a low-mass companion star (M_(star) \u2272 1.0 M_\u2299) and is likely to have a short orbital period (P_(orb) \u227216 h). Although AT2019wey began activation in the X-ray band during almost the entire outburst on March 8, 2020, it did not enter the soft state during the entire outburst. In this study, we present a detailed spectral analysis of AT2019wey in the low/hard state during its X-ray outburst on the basis of Nuclear Spectroscopic Telescope Array \\emph observations. We obtain tight constraints on several of its important physical parameters by applying the State-of-art \\texttt{relxill} relativistic reflection model family. In particular, we determine that the measured inner radius of the accretion disk is most likely to have extended to the innermost stable circular orbit (ISCO) radius, i.e., R_(in) = 1.38^(+0.23)_(\u22120.16) R_(ISCO). Hence, assuming R_(in) = R_(ISCO), we find the spin of AT2019wey to be a\u2217\u223c 0.97, which is close to the extreme and an inner disk inclination angle of ~i\u223c 22\u2218. Additionally, according to our adopted models, AT2019wey tends to have a relatively high iron abundance of A_(Fe)\u223c 5 A_(Fe,\u2299) and a high disk ionization state of log \u03be\u223c 3.4.",
"date": "2022-01",
"date_type": "published",
"publication": "Science China Physics, Mechanics and Astronomy",
"volume": "65",
"number": "1",
"publisher": "Springer Verlag",
"pagerange": "Art. No. 219512",
"id_number": "CaltechAUTHORS:20211208-951173000",
"issn": "1674-7348",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211208-951173000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400804"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1838114"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "XDB23040100"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1007/s11433-021-1790-7",
"primary_object": {
"basename": "2109.07357.pdf",
"url": "https://authors.library.caltech.edu/records/9dcsw-at394/files/2109.07357.pdf"
},
"pub_year": "2022",
"author_list": "Feng, Ye; Zhao, XueShan; et al."
},
{
"id": "https://authors.library.caltech.edu/records/p3qyq-abz53",
"eprint_id": 113141,
"eprint_status": "archive",
"datestamp": "2023-08-20 06:21:58",
"lastmod": "2025-02-01 19:06:58",
"type": "conference_item",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bucik-Radoslav",
"name": {
"family": "Bucik",
"given": "Radoslav"
},
"orcid": "0000-0001-7381-6949"
},
{
"id": "Mason-Glenn-M",
"name": {
"family": "Mason",
"given": "Glenn M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "G\u00f3mez-Herrero-Ra\u00fal",
"name": {
"family": "G\u00f3mez-Herrero",
"given": "Ra\u00fal"
}
},
{
"id": "Dayeh-Maher-A",
"name": {
"family": "Dayeh",
"given": "Maher A."
}
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "Mihir I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Lario-David",
"name": {
"family": "Lario",
"given": "David"
},
"orcid": "0000-0002-3176-8704"
},
{
"id": "Balmaceda-Laura-A",
"name": {
"family": "Balmaceda",
"given": "Laura A."
},
"orcid": "0000-0003-1162-5498"
},
{
"id": "Krupar-Vratislav",
"name": {
"family": "Krupar",
"given": "Vratislav"
},
"orcid": "0000-0001-6185-3945"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "Mark E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Wimmer-Schweingruber-Robert-F",
"name": {
"family": "Wimmer-Schweingruber",
"given": "Robert F."
},
"orcid": "0000-0002-7388-173X"
},
{
"id": "Ho-George-C",
"name": {
"family": "Ho",
"given": "George C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Rodriguez-Pacheco-Javier",
"name": {
"family": "Rodriguez-Pacheco",
"given": "Javier"
}
},
{
"id": "Nitta-Nariaki-V",
"name": {
"family": "Nitta",
"given": "Nariaki V."
}
},
{
"id": "K\u00fchl-Patrick",
"name": {
"family": "K\u00fchl",
"given": "Patrick"
}
},
{
"id": "Xu-Zigong",
"name": {
"family": "Xu",
"given": "Zigong"
},
"orcid": "0000-0002-9246-996X"
},
{
"id": "Asfaw-Tilaye-T",
"name": {
"family": "Asfaw",
"given": "Tilaye T."
}
}
]
},
"title": "Multi-spacecraft Observations of Gradual Solar Energetic Particle Events with Enhanced \u00b3He Abundance",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "Solar System Physics",
"note": "The copyright holder for this preprint is the author/funder. \n\nSupported by NASA LWS grant 80NSSC21K1316.\n\nSubmitted - essoar.10509271.2.pdf
",
"abstract": "Flare suprathermal ions with enhanced \u00b3He and heavy-ion abundances are an essential component of the seed population accelerated by CME-driven shocks in gradual solar energetic particle (GSEP) events. However, the mechanisms through which CME-driven shocks gain access to flare suprathermals and produce spectral and abundance variations in GSEP events remain largely unexplored. We report two recent GSEP events: one observed by Solar Orbiter on 2020 Nov 24 (the first GSEP event on Solar Orbiter) and the other by ACE on 2021 May 29 (the most intense GOES proton event in the present solar cycle). The events were preceded by impulsive SEP (ISEP) events. Abundances and energy spectra are markedly different in the examined events at < 1 MeV/nucleon. For example, in the May event, Fe/O is typical of ISEP events, a factor of 100 to 10 higher than Fe/O in the November event. \u00b3He abundance in the November event is high, typical of ISEP events, while in the May event, it is much lower, though finite. The May event shows a hard \u2074He spectrum with a power-law index of \u22121.6, and the November event a soft spectrum with an index of \u22123.5. The events were associated with halo CMEs with speeds around 900 km/s. The November event was also measured by Parker Solar Probe and the May event by STEREO-A and Solar Orbiter. This paper discusses the origin of vastly different abundances and spectral shapes in terms of variable remnant population from preceding ISEP events. Furthermore, we discuss a possible direct contribution from parent flares.",
"date": "2021-12-30",
"date_type": "published",
"publisher": "Wiley",
"id_number": "CaltechAUTHORS:20220127-677276900",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220127-677276900",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC21K1316"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1002/essoar.10509271.2",
"primary_object": {
"basename": "essoar.10509271.2.pdf",
"url": "https://authors.library.caltech.edu/records/p3qyq-abz53/files/essoar.10509271.2.pdf"
},
"pub_year": "2021",
"author_list": "Bucik, Radoslav; Mason, Glenn M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3wmng-ybt88",
"eprint_id": 112989,
"eprint_status": "archive",
"datestamp": "2023-08-22 12:53:00",
"lastmod": "2026-03-29 18:37:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Gorgone-Nicholas-M",
"name": {
"family": "Gorgone",
"given": "Nicholas M."
},
"orcid": "0000-0002-1653-6411"
},
{
"id": "Woudt-Patrick-A",
"name": {
"family": "Woudt",
"given": "Patrick A."
},
"orcid": "0000-0002-6896-1655"
},
{
"id": "Buckley-David-A-H",
"name": {
"family": "Buckley",
"given": "David"
},
"orcid": "0000-0002-7004-9956"
},
{
"id": "Mukai-Koji",
"name": {
"family": "Mukai",
"given": "Koji"
},
"orcid": "0000-0002-8286-8094"
},
{
"id": "Kouveliotou-Chryssa",
"name": {
"family": "Kouveliotou",
"given": "Chryssa"
},
"orcid": "0000-0003-1443-593X"
},
{
"id": "Huppenkothen-Daniela",
"name": {
"family": "Huppenkothen",
"given": "Daniela"
},
"orcid": "0000-0002-1169-7486"
},
{
"id": "G\u00f6\u011f\u00fc\u015f-Ersin",
"name": {
"family": "G\u00f6\u011f\u00fc\u015f",
"given": "Ersin"
},
"orcid": "0000-0002-5274-6790"
},
{
"id": "Bellm-Eric-C",
"name": {
"family": "Bellm",
"given": "Eric"
},
"orcid": "0000-0001-8018-5348"
},
{
"id": "Linford-Justin-D",
"name": {
"family": "Linford",
"given": "Justin D."
},
"orcid": "0000-0002-3873-5497"
},
{
"id": "van-der-Horst-Alexander-J",
"name": {
"family": "van der Horst",
"given": "Alexander J."
},
"orcid": "0000-0001-9149-6707"
},
{
"id": "Baring-Matthew-G",
"name": {
"family": "Baring",
"given": "Matthew G."
},
"orcid": "0000-0003-4433-1365"
},
{
"id": "Hartmann-Dieter",
"name": {
"family": "Hartmann",
"given": "Dieter"
},
"orcid": "0000-0002-8028-0991"
},
{
"id": "Barrett-Paul",
"name": {
"family": "Barrett",
"given": "Paul"
},
"orcid": "0000-0002-8456-1424"
},
{
"id": "Cenko-S-Bradley",
"name": {
"family": "Cenko",
"given": "Bradley"
},
"orcid": "0000-0003-1673-970X"
},
{
"id": "Graham-Melissa-Lynn",
"name": {
"family": "Graham",
"given": "Melissa"
},
"orcid": "0000-0002-9154-3136"
},
{
"id": "Granot-Jonathan",
"name": {
"family": "Granot",
"given": "Johnathan"
},
"orcid": "0000-0001-8530-8941"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kennea-Jamie-A",
"name": {
"family": "Kennea",
"given": "Jamie"
},
"orcid": "0000-0002-6745-4790"
},
{
"id": "O'Connor-Brendan-M",
"name": {
"family": "O'Connor",
"given": "Brendan M."
},
"orcid": "0000-0002-9700-0036"
},
{
"id": "Potter-Stephen-B",
"name": {
"family": "Potter",
"given": "Stephen"
},
"orcid": "0000-0002-5956-2249"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Slane-Patrick",
"name": {
"family": "Slane",
"given": "Patrick"
},
"orcid": "0000-0002-6986-6756"
},
{
"id": "Wijers-Ralph",
"name": {
"family": "Wijers",
"given": "Ralph"
},
"orcid": "0000-0002-3101-1808"
}
]
},
"title": "Swift/XRT Deep Galactic Plane Survey Discovery of a New Intermediate Polar Cataclysmic Variable, Swift J183920.1-045350",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Cataclysmic variable stars; DQ Herculis stars; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 April 10; revised 2021 September 10; accepted 2021 September 14; published 2021 December 24. \n\nThe authors wish to thank Sylvia Rose Kowalski and Deena Mickelson for their roles in VLA data acquisition. They also thank Hannes Breytenbach for taking some of the SAAO data. P.A.W. acknowledges financial support from the University of Cape Town and the National Research Foundation. The SALT observations reported here were obtained through the SALT Large Science program 2018-2-LSP-001, with D.B. as PI, who also acknowledges support of the National Research Foundation. C.K. and N.G. acknowledge support under NASA grant 80NSSC19K0916 and Smithsonian Astrophysical Observatory grant GO9-20057X. B.O. is supported in part by the National Aeronautics and Space Administration through grants NNX16AB66G, NNX17AB18G, and 80NSSC20K0389. \n\nWe thank the NRAO for the generous allocation of VLA time for our observations. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. \n\nThis work has made use of data from the European Space Agency mission Gaia, processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions participating in the Gaia Multilateral Agreement. \n\nFacilities: Swift - Swift Gamma-Ray Burst Mission, NuSTAR - , XMM-Newton - , Chandra - , SALT - , SAAO - , Gaia - , Pan-STARRS - , ZTF - , APO - , VLA - . \n\nSoftware: casa (McMullin et al. 2007), heasoft (v6.23; Nasa High Energy Astrophysics Science Archive Research Center (Heasarc), 2014), ds9 (Joye & Mandel 2003; Smithsonian Astrophysical Observatory 2000), sas (v1.2; Gabriel et al. 2004), pyspeckit (Ginsburg & Mirocha 2011), stingray (Huppenkothen et al. 2019, v0.1;), ciao (Fruscione et al. 2006, v4.9;), pydis (Davenport 2019), pysalt package (Crawford et al. 2010), python 3 (Van Rossum & Drake 2009), iraf (Tody 1986, 1993), vartools (Hartman & Bakos 2016)\n\nPublished - Gorgone_2021_ApJ_923_243.pdf
Submitted - 2103.14800.pdf
",
"abstract": "We report on the Swift/XRT Deep Galactic Plane Survey discovery and multiwavelength follow-up observations of a new intermediate polar (IP) cataclysmic variable, Swift J183920.1-045350. A 449.7 s spin period is found in XMM-Newton and NuSTAR data, accompanied by a 459.9 s optical period that is most likely the synodic, or beat period, produced from a 5.6 hr orbital period. The orbital period is seen with moderate significance in independent long-baseline optical photometry observations taken with the ZTF and SAAO telescopes. We find that the X-ray pulse fraction of the source decreases with increasing energy. The X-ray spectra are consistent with the presence of an Fe emission line complex with both local and interstellar absorption. In the optical spectra, strong H\u03b1, H i, He i, and He ii emission lines are observed, all common features in magnetic CVs. The source properties are thus typical of known IPs, with the exception of its estimated distance of 2.26_(\u22120.83)^(+1.93) kpc, which is larger than typical, extending the reach of the CV population in our Galaxy.",
"date": "2021-12-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "923",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 243",
"id_number": "CaltechAUTHORS:20220119-572561000",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220119-572561000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Southern African Large Telescope (SALT)",
"grant_number": "2018-2-LSP-001"
},
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0916"
},
{
"agency": "Smithsonian Astrophysical Observatory",
"grant_number": "GO9-20057X"
},
{
"agency": "NASA",
"grant_number": "NNX16AB66G"
},
{
"agency": "NASA",
"grant_number": "NNX17AB18G"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0389"
},
{
"agency": "Gaia Multilateral Agreement"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ac2738",
"primary_object": {
"basename": "2103.14800.pdf",
"url": "https://authors.library.caltech.edu/records/3wmng-ybt88/files/2103.14800.pdf"
},
"related_objects": [
{
"basename": "Gorgone_2021_ApJ_923_243.pdf",
"url": "https://authors.library.caltech.edu/records/3wmng-ybt88/files/Gorgone_2021_ApJ_923_243.pdf"
}
],
"pub_year": "2021",
"author_list": "Gorgone, Nicholas M.; Woudt, Patrick A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/p7s73-fem72",
"eprint_id": 113005,
"eprint_status": "archive",
"datestamp": "2023-08-20 06:11:57",
"lastmod": "2026-03-30 07:06:33",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Greffe-Timoth\u00e9e",
"name": {
"family": "Greffe",
"given": "Timothee"
}
},
{
"id": "Smith-R-M",
"name": {
"family": "Smith",
"given": "Roger"
},
"orcid": "0000-0001-7062-9726"
},
{
"id": "Sherman-Myles",
"name": {
"family": "Sherman",
"given": "Myles"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah"
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Hennessy-John",
"name": {
"family": "Hennessy",
"given": "John"
},
"orcid": "0000-0002-0135-0219"
},
{
"id": "Nikzad-Shouleh",
"name": {
"family": "Nikzad",
"given": "Shouleh"
}
}
]
},
"title": "Characterization of Low Light Performance of a CMOS sensor for Ultraviolet Astronomical Applications",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "CMOS, SRI mK\u2002nK, ultraviolet, dark current, glow suppression, dual-gain",
"note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank the SRI team for packaging multiple detectors and performing screening tests, and for their advice during our detector characterization effort. We acknowledge the support of JPL and Caltech's President and Director's Research and Development Fund (PDRDF Program). We also gratefully acknowledge the collaborative agreement between APL-SRI-JPL that made wafers available for this work.\n\nSubmitted - 2112.01691.pdf
",
"abstract": "CMOS detectors offer many advantages over CCDs for optical and UV astronomical applications, especially in space where high radiation tolerance is required. However, astronomical instruments are most often designed for low light-level observations demanding low dark current and read noise, good linearity and high dynamic range, characteristics that have not been widely demonstrated for CMOS imagers. We report the performance, over temperatures from 140 - 240 K, of a radiation hardened SRI 4Kx2K back-side illuminated CMOS image sensor with surface treatments that make it highly sensitive in blue and UV bands. After suppressing emission from glow sites resulting from defects in the engineering grade device examined in this work, a 0.077 me\u207b/s dark current floor is reached at 160 K, rising to 1 me\u207b/s at 184 K, rivaling that of the best CCDs. We examine the trade-off between readout speed and read noise, finding that 1.43 e\u207b median read noise is achieved using line-wise digital correlated double sampling at 700 kpix/s/ch corresponding to a 1.5 s readout time. The 15 ke\u207b well capacity in high gain mode extends to 120 ke\u207b in dual gain mode. Continued collection of photo-generated charge during readout enables a further dynamic range extension beyond 10\u2076 e\u207b effective well capacity with only 1% loss of exposure efficiency by combining short and long exposures. A quadratic fit to correct for non-linearity reduces gain correction residuals from 1.5% to 0.2% in low gain mode and to 0.4% in high gain mode. Cross-talk to adjacent pixels is only 0.4% vertically, 0.6% horizontally and 0.1% diagonally. These characteristics plus the relatively large 10 \u03bcm pixel size, quasi 4-side buttability, electronic shutter and sub-array readout make this sensor an excellent choice for wide field astronomical imaging in space, even at FUV wavelengths where sky background is very low.",
"date": "2021-12-03",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20220119-233946472",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220119-233946472",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "JPL President and Director's Fund"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.2112.01691",
"primary_object": {
"basename": "2112.01691.pdf",
"url": "https://authors.library.caltech.edu/records/p7s73-fem72/files/2112.01691.pdf"
},
"pub_year": "2021",
"author_list": "Greffe, Timothee; Smith, Roger; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8ydzc-cn778",
"eprint_id": 112893,
"eprint_status": "archive",
"datestamp": "2023-08-20 06:10:34",
"lastmod": "2026-03-30 06:22:26",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Maccarone-Thomas-J",
"name": {
"family": "Maccarone",
"given": "Thomas"
},
"orcid": "0000-0003-0976-4755"
},
{
"id": "Huppenkothen-Daniela",
"name": {
"family": "Huppenkothen",
"given": "Daniela"
},
"orcid": "0000-0002-1169-7486"
},
{
"id": "Israel-Gian-Luca",
"name": {
"family": "Israel",
"given": "Gian Luca"
}
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Brumback-McKinley-C",
"name": {
"family": "Brumback",
"given": "McKinley"
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "Matthew"
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Pilia-Maura",
"name": {
"family": "Pilia",
"given": "Maura"
}
},
{
"id": "Poutanen-J",
"name": {
"family": "Poutanen",
"given": "Juri"
},
"orcid": "0000-0002-0983-0049"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "Natalie"
}
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "The extreme mass transfer and high magnetic field of the first ultraluminous pulsar M82 X-2",
"ispublished": "unpub",
"full_text_status": "public",
"note": "The authors wish to thank W\u0142odek Klu\u017aniak and Alessandro Ridolfi for useful discussions, and the staff at the NuSTAR Science Operations Center at Caltech for the help in scheduling the observations and the frequent clock correction file updates, that allowed a prompt analysis of the data. MB was funded in part by PRIN TEC INAF 2019 \"SpecTemPolar! \u2013 Timing analysis in the era of high-throughput photon detectors\". MH is supported by an ESO fellowship. GLI acknowledges funding from the Italian MIUR PRIN grant 2017LJ39LM. ADJ was funded in part by the Chandra grant 803-0000-716015-404H00-6100-2723-4210-40716015HH83121. JP was supported by the grant 14.W03.31.0021 of the Ministry of Science and Higher Education of the Russian Federation and the Academy of Finland grant 333112. DJW acknowledges support from STFC in the form of an Ernest Rutherford Fellowship. HPE acknowledges support under NASA Contract No. NNG08FD60C. \n\nAll the analysis of this Paper was done using open-source software: Astropy, Stingray, HENDRICS, PINT, emcee, corner, scinum, and can easily be verified using the solution in Table 1. Figures were produced using the Matplotlib library and the Veusz software. The data used for this work come from the NuSTAR mission and are usually held private for one year, and made public on the High Energy Astrophysics Science archive (HEASARC) afterwise. NuSTAR is a Small Explorer mission led by Caltech and managed by JPL for NASA's Science Mission Directorate in Washington. NuSTAR was developed in partnership with the Danish Technical University and the Italian Space Agency (ASI). The spacecraft was built by Orbital Sciences Corp., Dulles, Virginia.\n\nSubmitted - 2112.00339.pdf
",
"abstract": "M82 X-2 is the first pulsating ultraluminous X-ray source (PULX) discovered. The luminosity of these extreme pulsars, if isotropic, implies an extreme mass transfer rate. An alternative is to assume a much lower mass transfer rate, but an apparent luminosity boosted by geometrical beaming. Only an independent measurement of the mass transfer can help discriminate between these two scenarios. In this Paper, we follow the orbit of the neutron star for seven years, measure the decay of the orbit, and demonstrate that this orbital decay is driven by extreme mass transfer of more than 150 times the mass transfer limit set by the Eddington luminosity. This measurement shows that the mass available to the accretor is more than enough to justify its luminosity, with no need for beaming. This also strongly favors models where the accretor is a highly-magnetized neutron star.",
"date": "2021-12-01",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20220113-234521215",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-234521215",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "PRIN 2019"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Ministero dell'Istruzione, dell'Universit\u00e0 e della Ricerca (MIUR)",
"grant_number": "2017LJ39LM"
},
{
"agency": "Chandra",
"grant_number": "803-0000-716015-404H00-6100-2723-4210-40716015HH83121"
},
{
"agency": "Ministry of Science and Higher Education of the Russian Federation",
"grant_number": "14.W03.31.0021"
},
{
"agency": "Academy of Finland",
"grant_number": "333112"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.48550/arXiv.2112.00339",
"primary_object": {
"basename": "2112.00339.pdf",
"url": "https://authors.library.caltech.edu/records/8ydzc-cn778/files/2112.00339.pdf"
},
"pub_year": "2021",
"author_list": "Bachetti, Matteo; Heida, Marianne; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tfzan-gfz75",
"eprint_id": 112438,
"eprint_status": "archive",
"datestamp": "2023-08-22 12:33:45",
"lastmod": "2026-03-29 15:29:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "de-Nolfo-Georgia-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Matthaeus-William-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Mitchell-John-Grant",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Roelof-Edmond-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Vourlidas-Angelos",
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Pulupa-Marc",
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"id": "MacDowall-Robert-J",
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
}
]
},
"title": "PSP/IS\u2299IS observations of the 29 November 2020 solar energetic particle event",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: particle emission / Sun: activity / solar-terrestrial relations; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 ESO 2021. \n\nSolar Orbiter First Results (Cruise Phase). \n\nReceived: 31 March 2021 Accepted: 23 August 2021. \n\nThis work was supported by NASA's Parker Solar Probe Mission, contract NNN06AA01C. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We thank all the scientists and engineers who have worked hard to make PSP a successful mission. In particular, we thank B. Kecman, W. R. Cook and J. Burnham, without whom the EPI-Hi instrument would not be possible. C. M. S. Cohen thanks T. Nieves-Chinchilla and A. Szabo for their helpful discussions regarding the shock and ICME observations, and N. Dresing for useful ones on electron ESP events. S. D. Bale acknowledges support of the Leverhulme Trust Visiting Professorship program. A. Vourlidas acknowledges support from NASA grants 80NSSC19K1261 and 80NSSC19K0069. The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) was produced by an international consortium of the Naval Research Laboratory (USA), Lockheed Martin Solar and Astrophysics Lab. (USA), NASA Goddard Space Flight Center (USA), Rutherford Appleton Laboratory (UK), University of Birmingham (UK), Max Planck Institute for Solar System Research (Germany), Centre Spatiale de Li\u00e8ge (Belgium), Institut d'Optique Theorique et Appliqu\u00e9e (France), and Institut d'Astrophysique Spatiale (France). STEREO/SECCHI data are available for download at https://secchi.nrl.navy.mil/. This paper uses data from the CACTus CME catalog, generated and maintained by the SIDC at the Royal Observatory of Belgium. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). The GOES X-ray data are available from the National Centers for Environmental Information (https://www.ngdc.noaa.gov/stp/spaceweather.html).\n\nPublished - aa40967-21.pdf
Supplemental Material - aa40967-21-mov1-olm.mp4
",
"abstract": "Aims. On 29 November 2020, at 12:34 UT, active region 12790 erupted with an M4.4 class flare and a 1700 km s\u207b\u00b9 coronal mass ejection. Parker Solar Probe (PSP) was completing its seventh orbit around the Sun and was located at 0.8 au when the Integrated Science Investigation of the Sun (IS\u2299IS) measured the ensuing mid-sized solar energetic particle (SEP) event. Not only was this the first SEP event with heavy ions above 10 MeV nuc\u207b\u00b9 to be measured by IS\u2299IS, it was also measured by several spacecraft positioned around the Sun, making it the first circumsolar event of solar cycle 25. Here we describe an overview of the SEP event characteristics at PSP. \n\nMethods. Fluence spectra for electrons, H, He, O, and Fe were calculated for the decay portion of the event. For the entire time period of the event, it was possible to calculate fluence spectra for electrons, O, and Fe only due to instrumental mode changes in one of the IS\u2299IS telescopes, affecting H and He during the period of peak intensities. Using higher time resolution data, we also studied the onset of the event and temporal variations in the particle intensities at the shock and during the magnetic cloud passage. \n\nResults. During the decay, the ion spectra are consistent with power laws at low energies with an exponential rollover at a few MeV nuc\u207b\u00b9, while the electron spectrum is consistent with a power law of index \u22125.3. Based on fits to the spectra, Fe/O and He/H abundance ratios as a function of energy are calculated and found to be nominal for large SEP events at hundreds of keV/nuc, but decrease strongly with increasing energy. The full-event spectra for O and Fe have similar shapes to those of the decay, but with higher roll-over energies. The electron spectrum for the full event is harder with an index of \u22123.4 and there is some evidence of higher energy components near \u223c2 MeV and above \u223c4 MeV. Despite the spacecraft being tilted 45\u00b0 with respect to the nominal orientation of the spacecraft's long axis pointed towards the Sun, there is some anisotropy apparent in MeV protons during the onset of the event. Velocity dispersion is also evident, consistent with a solar release time of 13:15 UT and pathlength of 1.3 au. The arrival of the related magnetic cloud resulted in the suppression of SEP intensities, although a brief increase in particle intensities suggests PSP moved out of the cloud for \u223c30 min. This appears to be the first medium-sized event in the rise of cycle 25 activity, with additional large events likely to occur. Additional details of the event beyond this overview can be found in several related papers.",
"date": "2021-12",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "656",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A29",
"id_number": "CaltechAUTHORS:20211214-82701000",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211214-82701000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1261"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0069"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202140967",
"primary_object": {
"basename": "aa40967-21-mov1-olm.mp4",
"url": "https://authors.library.caltech.edu/records/tfzan-gfz75/files/aa40967-21-mov1-olm.mp4"
},
"related_objects": [
{
"basename": "aa40967-21.pdf",
"url": "https://authors.library.caltech.edu/records/tfzan-gfz75/files/aa40967-21.pdf"
}
],
"pub_year": "2021",
"author_list": "Cohen, C. M. S.; Christian, E. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/92j34-vv776",
"eprint_id": 112477,
"eprint_status": "archive",
"datestamp": "2023-08-22 12:34:27",
"lastmod": "2026-03-29 16:10:24",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pecora-Francesco",
"name": {
"family": "Pecora",
"given": "F."
},
"orcid": "0000-0003-4168-590X"
},
{
"id": "Servidio-Sergio",
"name": {
"family": "Servidio",
"given": "S."
},
"orcid": "0000-0001-8184-2151"
},
{
"id": "Greco-Antonella",
"name": {
"family": "Greco",
"given": "A."
}
},
{
"id": "Matthaeus-William-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Getachew-Tibebu",
"name": {
"family": "Getachew",
"given": "T."
},
"orcid": "0000-0003-2408-4619"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Roelof-Edmond-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
}
]
},
"title": "Parker Solar Probe observations of helical structures as boundaries for energetic particles",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "magnetic fields, plasmas, Sun: magnetic fields, Sun: particle emission, solar wind; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nAccepted 2021 September 9. Received 2021 September 9; in original form 2021 June 22. \n\nThis research is partially supported by the Parker Solar Probe mission and the IS\u2299IS project (contract NNN06AA01C) and a subcontract to the University of Delaware from Princeton University (SUB0000165). Additional support is acknowledged from the NASA's Living With a Star (LWS) program (NNX17AB79G) and the Heliospheric Supporting Research (HSR) program (80NSSC18K1210 and 80NSSC18K1648). Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's LWS program (contract NNN06AA01C). SS has received funding from the European Unions Horizon 2020 research and innovation programme under grant agreement No. 776262 (AIDA, www.aida-space.eu). We thank the IS\u2299IS team for its support as well as the FIELDS and SWEAP teams for cooperation.\n\nDATA AVAILABILITY. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - stab2659.pdf
Accepted Version - 2109.04571.pdf
",
"abstract": "Energetic particle transport in the interplanetary medium is known to be affected by magnetic structures. It has been demonstrated for solar energetic particles in near-Earth orbit studies, and also for the more energetic cosmic rays. In this paper, we show observational evidence that intensity variations of solar energetic particles can be correlated with the occurrence of helical magnetic flux tubes and their boundaries. The analysis is carried out using data from Parker Solar Probe orbit 5, in the period 2020 May 24 to June 2. We use FIELDS magnetic field data and energetic particle measurements from the Integrated Science Investigation of the Sun (IS\u2299IS) suite on the Parker Solar Probe. We identify magnetic flux ropes by employing a real-space evaluation of magnetic helicity, and their potential boundaries using the Partial Variance of Increments method. We find that energetic particles are either confined within or localized outside of helical flux tubes, suggesting that the latter act as transport boundaries for particles, consistent with previously developed viewpoints.",
"date": "2021-12",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "508",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2114-2122",
"id_number": "CaltechAUTHORS:20211215-622281000",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211215-622281000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "SUB0000165"
},
{
"agency": "NASA",
"grant_number": "NNX17AB79G"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1210"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1648"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "776262"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stab2659",
"primary_object": {
"basename": "2109.04571.pdf",
"url": "https://authors.library.caltech.edu/records/92j34-vv776/files/2109.04571.pdf"
},
"related_objects": [
{
"basename": "stab2659.pdf",
"url": "https://authors.library.caltech.edu/records/92j34-vv776/files/stab2659.pdf"
}
],
"pub_year": "2021",
"author_list": "Pecora, F.; Servidio, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/727mj-dnb25",
"eprint_id": 112437,
"eprint_status": "archive",
"datestamp": "2023-08-22 12:33:37",
"lastmod": "2026-03-29 13:48:18",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mason-Glenn-M",
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Andrews",
"given": "G. B."
}
},
{
"name": {
"family": "Berger",
"given": "L."
}
},
{
"name": {
"family": "Boden",
"given": "S."
}
},
{
"name": {
"family": "B\u00f6ttcher",
"given": "S."
}
},
{
"name": {
"family": "Cernuda",
"given": "I."
}
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"name": {
"family": "Desai",
"given": "M. I."
}
},
{
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"name": {
"family": "Eldrum",
"given": "S."
}
},
{
"name": {
"family": "Elftmann",
"given": "R."
}
},
{
"name": {
"family": "Kollhoff",
"given": "A."
}
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "G\u00f3mez-Herrero",
"given": "R."
}
},
{
"name": {
"family": "Hayes",
"given": "J."
}
},
{
"name": {
"family": "Janitzek",
"given": "N. P."
}
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Korth",
"given": "A."
}
},
{
"name": {
"family": "K\u00fchl",
"given": "P."
}
},
{
"name": {
"family": "Kulkarni",
"given": "S. R."
}
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"name": {
"family": "Espinosa Lara",
"given": "F."
}
},
{
"name": {
"family": "Lees",
"given": "W. J."
}
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Mall",
"given": "U."
}
},
{
"name": {
"family": "Martin",
"given": "C."
}
},
{
"name": {
"family": "Mart\u00ednez Hell\u00edn",
"given": "A."
}
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"name": {
"family": "Pacheco",
"given": "D."
}
},
{
"name": {
"family": "Parra Espada",
"given": "P."
}
},
{
"name": {
"family": "Prieto",
"given": "M."
}
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Ravanbakhsh",
"given": "A."
}
},
{
"name": {
"family": "Rodr\u00edguez-Pacheco",
"given": "J."
}
},
{
"name": {
"family": "Rodr\u00edguez Polo",
"given": "O."
}
},
{
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"name": {
"family": "S\u00e1nchez-Prieto",
"given": "S."
}
},
{
"name": {
"family": "Schlemm",
"given": "C. E."
}
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Seifert",
"given": "H."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Terasa",
"given": "J. C."
}
},
{
"name": {
"family": "Tyagi",
"given": "K."
}
},
{
"name": {
"family": "Freiherr von Forstner",
"given": "J. L."
},
"orcid": "0000-0002-1390-4776"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Wimmer-Schweingruber",
"given": "R. F."
}
},
{
"name": {
"family": "Xu",
"given": "Z. G."
}
},
{
"name": {
"family": "Yedla",
"given": "M."
}
}
]
},
"title": "Solar energetic particle heavy ion properties in the widespread event of 2020 November 29",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "acceleration of particles / Sun: abundances / Sun: flares / Sun: particle emission; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 ESO 2021. \n\nSolar Orbiter First Results (Cruise Phase).\n\nReceived: 13 May 2021 Accepted: 17 June 2021. \n\nSolar Orbiter is a mission of international cooperation between ESA and NASA, operated by ESA. The Suprathermal Ion Spectrograph (SIS) is a European facility instrument funded by ESA. We thank ESA and NASA for their support of the Solar Orbiter, PSP, STEREO and ACE missions whose data were used in this Letter. Complete acknowledgements for the missions and specific instruments are too lengthy to include here but are given in the references in Table 1. Solar Orbiter and Parker Solar Probe post-launch work at JHU/APL is supported by NASA contract NNN06AA01C.\n\nPublished - aa41310-21.pdf
",
"abstract": "Context. Following a multi-year minimum of solar activity, a solar energetic particle event on 2020 Nov. 29 was observed by multiple spacecraft covering a wide range of solar longitudes including ACE, the Solar Terrestrial Relations Observatory-A, and the recently launched Parker Solar Probe and Solar Orbiter. \n\nAims. Multi-point observations of a solar particle event, combined with remote-sensing imaging of flaring, shocks, and coronal mass ejections allows for a global picture of the event to be synthesized, and made available to the modeling community to test, constrain, and refine models of particle acceleration and transport according to such parameters as shock geometries and particle mass-to-charge ratios.\nMethods. Detailed measurements of heavy ion intensities, time dependence, fluences, and spectral slopes provided the required test data for this study. \n\nResults. The heavy ion abundances, timing, and spectral forms for this event fall well within the range found in prior surveys at 1 au. The spectra were well fitted by broken power law shapes; the Fe/O ratio was somewhat lower than the average of other events. In addition, \u00b3He/\u2074He was very low, with only the upper limits established here.",
"date": "2021-12",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "656",
"publisher": "EDP Sciences",
"pagerange": "Art. No. L12",
"id_number": "CaltechAUTHORS:20211214-82643000",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211214-82643000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202141310",
"primary_object": {
"basename": "aa41310-21.pdf",
"url": "https://authors.library.caltech.edu/records/727mj-dnb25/files/aa41310-21.pdf"
},
"pub_year": "2021",
"author_list": "Mason, G. M.; Cohen, C. M. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/wv2qc-wd959",
"eprint_id": 112439,
"eprint_status": "archive",
"datestamp": "2023-08-22 12:33:51",
"lastmod": "2026-03-30 13:48:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kollhoff-Alexander",
"name": {
"family": "Kollhoff",
"given": "A."
},
"orcid": "0000-0002-9471-5132"
},
{
"name": {
"family": "Kouloumvakos",
"given": "A."
}
},
{
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Dresing",
"given": "N."
}
},
{
"name": {
"family": "G\u00f3mez-Herrero",
"given": "R."
}
},
{
"name": {
"family": "Rodr\u00edguez-Garc\u00eda",
"given": "L."
}
},
{
"name": {
"family": "Malandraki",
"given": "O. E."
},
"orcid": "0000-0002-4751-6835"
},
{
"name": {
"family": "Richardson",
"given": "I. G."
},
"orcid": "0000-0002-3855-3634"
},
{
"name": {
"family": "Posner",
"given": "A."
},
"orcid": "0000-0003-1572-8734"
},
{
"name": {
"family": "Klein",
"given": "K.-L."
}
},
{
"name": {
"family": "Pacheco",
"given": "D."
}
},
{
"name": {
"family": "Klassen",
"given": "A."
}
},
{
"name": {
"family": "Heber",
"given": "B."
},
"orcid": "0000-0003-0960-5658"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Laitinen",
"given": "T."
}
},
{
"name": {
"family": "Cernuda",
"given": "I."
}
},
{
"name": {
"family": "Dalla",
"given": "S."
}
},
{
"name": {
"family": "Espinosa Lara",
"given": "F."
}
},
{
"name": {
"family": "Vainio",
"given": "R."
}
},
{
"name": {
"family": "K\u00f6berle",
"given": "M."
}
},
{
"name": {
"family": "K\u00fchl",
"given": "R."
}
},
{
"name": {
"family": "Xu",
"given": "Z. G."
}
},
{
"name": {
"family": "Berger",
"given": "L."
}
},
{
"name": {
"family": "Eldrum",
"given": "S."
}
},
{
"name": {
"family": "Br\u00fcdern",
"given": "M."
}
},
{
"name": {
"family": "Laurenza",
"given": "M."
}
},
{
"name": {
"family": "Kilpua",
"given": "E. J."
}
},
{
"name": {
"family": "Aran",
"given": "A."
}
},
{
"name": {
"family": "Rouillard",
"given": "A. P."
}
},
{
"name": {
"family": "Bu\u010dik",
"given": "R."
},
"orcid": "0000-0001-7381-6949"
},
{
"name": {
"family": "Wijsen",
"given": "N."
}
},
{
"name": {
"family": "Pomoell",
"given": "J."
}
},
{
"name": {
"family": "Wimmer-Schweingruber",
"given": "R. F."
}
},
{
"name": {
"family": "Martin",
"given": "C."
}
},
{
"name": {
"family": "B\u00f6ttcher",
"given": "S. I."
}
},
{
"name": {
"family": "Freiherr von Forstner",
"given": "J. L."
}
},
{
"name": {
"family": "Terasa",
"given": "J.-C."
}
},
{
"name": {
"family": "Boden",
"given": "S."
}
},
{
"name": {
"family": "Kulkarni",
"given": "S. R."
}
},
{
"name": {
"family": "Ravanbakhsh",
"given": "A."
}
},
{
"name": {
"family": "Yedla",
"given": "M."
}
},
{
"name": {
"family": "Janitzek",
"given": "N."
}
},
{
"name": {
"family": "Rodr\u00edguez-Pacheco",
"given": "J."
}
},
{
"name": {
"family": "Prieto Mateo",
"given": "M."
}
},
{
"name": {
"family": "S\u00e1nchez Prieto",
"given": "S."
}
},
{
"name": {
"family": "Parra Espada",
"given": "P."
}
},
{
"name": {
"family": "Rodr\u00edguez Polo",
"given": "O."
}
},
{
"name": {
"family": "Mart\u00ednez Hell\u00edn",
"given": "A."
}
},
{
"name": {
"family": "Carcaboso",
"given": "F."
}
},
{
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Andrews",
"given": "G. Bruce"
}
},
{
"name": {
"family": "Schlemm",
"given": "C. E."
}
},
{
"name": {
"family": "Seifert",
"given": "H."
}
},
{
"name": {
"family": "Tyagi",
"given": "K."
}
},
{
"name": {
"family": "Lees",
"given": "W. J."
}
},
{
"name": {
"family": "Hayes",
"given": "J."
}
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Krupar",
"given": "V."
}
},
{
"name": {
"family": "Horbury",
"given": "T. S."
}
},
{
"name": {
"family": "Angelini",
"given": "V."
}
},
{
"name": {
"family": "Evans",
"given": "V."
}
},
{
"name": {
"family": "O'Brien",
"given": "H."
}
},
{
"name": {
"family": "Maksimovic",
"given": "M."
}
},
{
"name": {
"family": "Khotyaintsev",
"given": "Yu. V."
}
},
{
"name": {
"family": "Vecchio",
"given": "A."
},
"orcid": "0000-0002-6254-1617"
},
{
"name": {
"family": "Steinvall",
"given": "K."
}
},
{
"name": {
"family": "Asvestari",
"given": "E."
}
}
]
},
"title": "The first widespread solar energetic particle event observed by Solar Orbiter on 2020 November 29",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: particle emission / Sun: heliosphere / Sun: coronal mass ejections (CMEs) / Sun: flares / interplanetary medium; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 A. Kollhoff et al. 2021. Licence Creative CommonsOpen Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nSolar Orbiter First Results (Cruise Phase).\n\nReceived: 30 March 2021 Accepted: 24 May 2021. \n\nSolar Orbiter is a space mission of international collaboration between ESA and NASA, operated by ESA. The CAU Kiel team acknowledges support from the German Federal Ministry for Economic Affairs and Energy, the German Space Agency (Deutsches Zentrum f\u00fcr Luft- und Raumfahrt e.V., DLR) under grants 50OT0901, 50OT1202, 50OT1702, and 50OT2002. A.K. acknowledges financial support from the ANR COROSHOCK project (ANR-17-CE31-0006-01). D.L. acknowledges support from NASA-HGI grant NNX16AF73G and the NASA Program NNH17ZDA001N-LWS. This study has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 101004159 (SERPENTINE). The U. Turku team acknowledges funding by the Academy of Finland (Grant No. 336809). The UAH team acknowledges financial support by the Spanish Ministerio de Ciencia, Innovaci\u00f3n y Universidades FEDER/MCIU/AEI Projects ESP2017-88436-R and PID2019-104863RB-I00/AEI/10.13039/501100011033. L.R.G. is also supported by the European Space Agency, under the ESA/NPI program, and acknowledges the work performed by Laura Balmaceda and Hebe Cremades in the 3D reconstruction of the CMEs used in the ENLIL simulation. ENLIL simulation results have been provided by the Community Coordinated Modeling Center at NASA Goddard Space Flight Center (GSFC) through their public Runs on Request system (http://ccmc.gsfc.nasa.gov; run IDs Laura_Rodriguez-Garcia_031321_SH_1). The WSA model was developed by C. N. Arge, currently at GSFC, and the ENLIL Model was developed by D. Odstrcil, currently at George Mason University. We thank the STEREO: SECCHI, S/WAVES; SOHO: LASCO; Wind/WAVES; and SDO/AIA teams for providing the data used in this study. The STEREO SECCHI data are produced by a consortium of RAL (UK), NRL (USA), LMSAL (USA), GSFC (USA), MPS (Germany), CSL (Belgium), IOTA (France), and IAS (France). SOHO is a mission of international cooperation between ESA and NASA. The SDO/AIA data are provided by the Joint Science Operations Center (JSOC) Science Data Processing (SDP). We thank the radio monitoring service at LESIA (Observatoire de Paris) for providing value-added data that have been used for this study. The ORFEES radio-spectrograph (Observations Radio pour FEDOME et l'Etude des Eruptions Solaires) is the result of a partnership between Paris Observatory and the French Air Force. CALLISTO is a radio spectrograph network organized by the Institute of Astronomy, ETH Zurich and FHNW Windisch, Switzerland. We acknowledge data from the instruments in Glasgow (UK), Heiterswil (Switzerland), and Trieste (Italy). The RPW instrument has been designed and funded by CNES, CNRS, the Paris Observatory, The Swedish National Space Agency, ESA-PRODEX and all the participating institutes. I.G.R. acknowledges support from NASA programs NNH19ZDA001N-HSR and NNH19ZDA001N-LWS, and the STEREO mission. IRFU team acknowledges support from the Swedish National Space Agency grant 20/136. A.A. acknowledges the support of the Spanish Ministerio de Ciencia e Innovaci\u00f3n (MICINN) under grant PID2019- 105510GB-C31 and through the 'Center of Excellence Mar\u00eda de Maeztu 2020-2023' award to the ICCUB (CEX2019-000918- M). F.C. acknowledges the financial support by the Spanish MINECO-FPI-2016 predoctoral grant with FSE. E.A. would like to acknowledge the financial support by the Academy of Finland (Postdoctoral Grant No 322455). V.K. acknowledges the support by NASA under grants 18-2HSWO218_2-0010 and 19-HSR-19_2-0143. Solar Orbiter magnetometer operations are funded by the UK Space Agency (grant ST/T001062/1). T.S.H. is supported by STFC grant ST/S000364/1. T.L. and S.D. acknowledge support from the UK Science and Technology Facilities Council (STFC; grant ST/R000425/1).\n\nPublished - aa40937-21.pdf
",
"abstract": "Context. On 2020 November 29, the first widespread solar energetic particle (SEP) event of solar cycle 25 was observed at four widely separated locations in the inner (\u22721\u2006AU) heliosphere. Relativistic electrons as well as protons with energies > 50\u2006MeV were observed by Solar Orbiter (SolO), Parker Solar Probe, the Solar Terrestrial Relations Observatory (STEREO)-A and multiple near-Earth spacecraft. The SEP event was associated with an M4.4 class X-ray flare and accompanied by a coronal mass ejection and an extreme ultraviolet (EUV) wave as well as a type II radio burst and multiple type III radio bursts. \n\nAims. We present multi-spacecraft particle observations and place them in context with source observations from remote sensing instruments and discuss how such observations may further our understanding of particle acceleration and transport in this widespread event. \n\nMethods. Velocity dispersion analysis (VDA) and time shift analysis (TSA) were used to infer the particle release times at the Sun. Solar wind plasma and magnetic field measurements were examined to identify structures that influence the properties of the energetic particles such as their intensity. Pitch angle distributions and first-order anisotropies were analyzed in order to characterize the particle propagation in the interplanetary medium. \n\nResults. We find that during the 2020 November 29 SEP event, particles spread over more than 230\u00b0 in longitude close to 1\u2006AU. The particle onset delays observed at the different spacecraft are larger as the flare\u2013footpoint angle increases and are consistent with those from previous STEREO observations. Comparing the timing when the EUV wave intersects the estimated magnetic footpoints of each spacecraft with particle release times from TSA and VDA, we conclude that a simple scenario where the particle release is only determined by the EUV wave propagation is unlikely for this event. Observations of anisotropic particle distributions at SolO, Wind, and STEREO-A do not rule out that particles are injected over a wide longitudinal range close to the Sun. However, the low values of the first-order anisotropy observed by near-Earth spacecraft suggest that diffusive propagation processes are likely involved.",
"date": "2021-12",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "656",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A20",
"id_number": "CaltechAUTHORS:20211214-82752000",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211214-82752000",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT0901"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT1202"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT1702"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50OT2002"
},
{
"agency": "Agence Nationale pour la Recherche (ANR)",
"grant_number": "ANR-17-CE31-0006-01"
},
{
"agency": "NASA",
"grant_number": "NNX16AF73G"
},
{
"agency": "NASA",
"grant_number": "NNH17ZDA001N-LWS"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "101004159"
},
{
"agency": "Academy of Finland",
"grant_number": "336809"
},
{
"agency": "Fondo Europeo de Desarrollo Regional (FEDER)"
},
{
"agency": "Ministerio de Ciencia, Innovaci\u00f3n y Universidades (MICIU)",
"grant_number": "ESP2017-88436-R"
},
{
"agency": "Ministerio de Ciencia, Innovaci\u00f3n y Universidades (MICIU)",
"grant_number": "PID2019-104863RB-I00/AEI/10.13039/501100011033"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Paris Observatory"
},
{
"agency": "Swedish National Space Agency",
"grant_number": "20/136"
},
{
"agency": "NASA",
"grant_number": "NNH19ZDA001N-HSR"
},
{
"agency": "NASA",
"grant_number": "NNH19ZDA001N-LWS"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCINN)",
"grant_number": "PID2019-105510GB-C31"
},
{
"agency": "Centro de Excelencia Severo Ochoa",
"grant_number": "CEX2019-000918-M"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)"
},
{
"agency": "Academy of Finland",
"grant_number": "322455"
},
{
"agency": "NASA",
"grant_number": "18-2HSWO218_2-0010"
},
{
"agency": "NASA",
"grant_number": "19-HSR-19_2-0143"
},
{
"agency": "United Kingdom Space Agency (UKSA)",
"grant_number": "ST/T001062/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/S000364/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/R000425/1"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202140937",
"primary_object": {
"basename": "aa40937-21.pdf",
"url": "https://authors.library.caltech.edu/records/wv2qc-wd959/files/aa40937-21.pdf"
},
"pub_year": "2021",
"author_list": "Kollhoff, A.; Kouloumvakos, A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7z51y-6z958",
"eprint_id": 112026,
"eprint_status": "archive",
"datestamp": "2023-08-22 11:58:08",
"lastmod": "2026-03-28 23:30:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lazar-Hadar",
"name": {
"family": "Lazar",
"given": "Hadar"
},
"orcid": "0000-0002-2752-9524"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Hadar-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "Douglas J. K."
}
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "Fuerst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Hare-Jeremy",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Shaw-Aarran-W",
"name": {
"family": "Shaw",
"given": "Aarran W."
},
"orcid": "0000-0002-8808-520X"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Spectral and Timing Analysis of NuSTAR and Swift/XRT Observations of the X-Ray Transient MAXI J0637\u2013430",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Low-mass x-ray binary stars; Black hole physics; Space and Planetary Science; Astronomy and Astrophysics",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 June 17; revised 2021 July 28; accepted 2021 August 5; published 2021 November 10. \n\nThis work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This work also made use of data from the Neil Gehrels Swift Observatory. H.L. and J.A.T. acknowledge partial support under NASA NuSTAR Guest Investigator grant 80NSSC20K0644. J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the Universities Space Research Association under contract with NASA. J.A.G. acknowledges support from NASA NuSTAR Guest Investigator grant 80NSSC20K1238, and from the Alexander von Humboldt Foundation. J.J. acknowledges support from the fellowship of China Postdoctoral Science Foundation (2021M691822), the Tsinghua Shuimu Scholar Program and the Tsinghua Astrophysics Outstanding Fellowship. Thank you to Dr. Thomas Dauser and Dr. Jack Steiner for the useful comments along the way. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift/XRT - . \n\nSoftware: XSPEC (v12.11.1c Arnaud 1996), HEAsoft (v6.27.2), relxill suite (Dauser et al. 2014; Garc\u00eda et al. 2014).\n\nPublished - Lazar_2021_ApJ_921_155.pdf
Accepted Version - 2108.03299.pdf
",
"abstract": "We present results for the first observed outburst from the transient X-ray binary source MAXI J0637\u2013430. This study is based on eight observations from the Nuclear Spectroscopic Telescope Array (NuSTAR) and six observations from the Neil Gehrels Swift Observatory X-Ray Telescope (Swift/XRT) collected from 2019 November 19 to 2020 April 26 as the 3\u201379 keV source flux declined from 8.2 \u00d7 10\u207b\u00b9\u2070 to 1.4 \u00d7 10\u207b\u00b9\u00b2 erg cm\u207b\u00b2 s\u207b\u00b9. We see the source transition from a soft state with a strong disk-blackbody component to a hard state dominated by a power-law or thermal Comptonization component. NuSTAR provides the first reported coverage of MAXI J0637\u2013430 above 10 keV, and these broadband spectra show that a two-component model does not provide an adequate description of the soft-state spectrum. As such, we test whether blackbody emission from the plunging region could explain the excess emission. As an alternative, we test a reflection model that includes a physical Comptonization continuum. Finally, we also test a spectral component based on reflection of a blackbody illumination spectrum, which can be interpreted as a simple approximation to the reflection produced by returning disk radiation due to the bending of light by the strong gravity of the black hole. We discuss the physical implications of each scenario and demonstrate the value of constraining the source distance.",
"date": "2021-11-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "921",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 155",
"id_number": "CaltechAUTHORS:20211123-234017978",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211123-234017978",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0644"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1238"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "China Postdoctoral Science Foundation",
"grant_number": "2021M691822"
},
{
"agency": "Tsinghua University"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac1bab",
"primary_object": {
"basename": "2108.03299.pdf",
"url": "https://authors.library.caltech.edu/records/7z51y-6z958/files/2108.03299.pdf"
},
"related_objects": [
{
"basename": "Lazar_2021_ApJ_921_155.pdf",
"url": "https://authors.library.caltech.edu/records/7z51y-6z958/files/Lazar_2021_ApJ_921_155.pdf"
}
],
"pub_year": "2021",
"author_list": "Lazar, Hadar; Tomsick, John A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kq3fm-knr27",
"eprint_id": 111901,
"eprint_status": "archive",
"datestamp": "2023-08-20 05:50:05",
"lastmod": "2026-03-29 17:54:40",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cooper-Kristopher",
"name": {
"family": "Cooper",
"given": "Kristopher"
},
"orcid": "0000-0001-8589-3378"
},
{
"id": "Hannah-Iain-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Glesener-Lindsay",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Krucker-S\u00e4m",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
},
"orcid": "0000-0002-2002-9180"
},
{
"id": "Hudson-Hugh-S",
"name": {
"family": "Hudson",
"given": "Hugh S."
},
"orcid": "0000-0001-5685-1283"
},
{
"id": "White-Stephen-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
},
{
"id": "Smith-David-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
},
{
"id": "Duncan-Jessie",
"name": {
"family": "Duncan",
"given": "Jessie"
},
"orcid": "0000-0002-6872-4406"
}
]
},
"title": "NuSTAR observations of a repeatedly microflaring active region",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: activity \u2013 Sun: corona \u2013 Sun: flares \u2013 Sun: magnetic fields \u2013 Sun: X-rays, gamma-rays",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of The Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nAccepted 2021 August 3. Received 2021 July 29; in original form 2021 May 5. Published: 19 August 2021. \n\nThis paper made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, funded by the National Aeronautics and Space Administration. These observations were supported through the NuSTAR Guest Observer program (NASA grant 80NSSC18K1744). This research used version 2.0.6 (Mumford et al. 2021) of the SUNPY open source software package (SunPy Community et al. 2020), version 0.4.0 (Barnes et al. 2020a) of the\u2009AIAPY open source software package (Barnes et al. 2020b), and made use of ASTROPY,3 a community-developed core PYTHON package for Astronomy (The Astropy Collaboration 2018). Other PYTHON packages that were extensively used were MATPLOTLIB (Hunter 2007), NUMPY (Harris et al. 2020), and SCIPY (Virtanen et al. 2020). This research also made use of HEASOFT (a unified release of FTOOLS and XANADU software packages) and NuSTAR Data Analysis Software (NUSTARDAS). This paper also made use of the SolarSoft IDL distribution (SSW) from the IDL Astronomy Library. We would like to thank the anonymous reviewer for their helpful feedback. \n\nKC is supported by a Royal Society Research Fellows Enhancement Award (RGF\\EA\\180010) and IGH is supported by a Royal Society University Fellowship (URF\\R\\180010). \n\nData Availability: All data used are publicly available. SDO data can be obtained from the Joint Science Operations Center (JSOC)4 using SUNPY'SFido5 object while the NuSTAR data are available from the NuSTAR Master Catalog6 with the OBSIDs 80414201001, 80414202001, 80414203001, 80415201001, 80415202001, and 80415203001.\n\nPublished - stab2283.pdf
Accepted Version - 2109.00263.pdf
",
"abstract": "We investigate the spatial, temporal, and spectral properties of 10 microflares from AR12721 on 2018 September 9 and 10 observed in X-rays using the Nuclear Spectroscopic Telescope ARray and the Solar Dynamic Observatory's Atmospheric Imaging Assembly and Helioseismic and Magnetic Imager. We find GOES sub-A class equivalent microflare energies of 10\u00b2\u2076\u201310\u00b2\u2078 erg reaching temperatures up to 10 MK with consistent quiescent or hot active region (AR) core plasma temperatures of 3\u20134 MK. One microflare (SOL2018-09-09T10:33), with an equivalent GOES class of A0.1, has non-thermal hard X-ray emission during its impulsive phase (of non-thermal power \u223c7 \u00d7 10\u00b2\u2074 erg s\u207b\u00b9) making it one of the faintest X-ray microflares to have direct evidence for accelerated electrons. In 4 of the 10 microflares, we find that the X-ray time profile matches fainter and more transient sources in the extreme-ultraviolet, highlighting the need for observations sensitive to only the hottest material that reaches temperatures higher than those of the AR core (>5 MK). Evidence for corresponding photospheric magnetic flux cancellation/emergence present at the footpoints of eight microflares is also observed.",
"date": "2021-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "507",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3936-3951",
"id_number": "CaltechAUTHORS:20211116-184723183",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211116-184723183",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1744"
},
{
"agency": "Royal Society",
"grant_number": "RGF\\EA\\180010"
},
{
"agency": "Royal Society",
"grant_number": "URF\\R\\180010"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/stab2283",
"pmcid": "PMC8753558",
"primary_object": {
"basename": "2109.00263.pdf",
"url": "https://authors.library.caltech.edu/records/kq3fm-knr27/files/2109.00263.pdf"
},
"related_objects": [
{
"basename": "stab2283.pdf",
"url": "https://authors.library.caltech.edu/records/kq3fm-knr27/files/stab2283.pdf"
}
],
"pub_year": "2021",
"author_list": "Cooper, Kristopher; Hannah, Iain G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/yqpbf-qmh66",
"eprint_id": 112872,
"eprint_status": "archive",
"datestamp": "2023-08-20 05:41:08",
"lastmod": "2026-03-28 21:09:42",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
}
]
},
"title": "2021 Effective Area calibration of the Nuclear Spectroscopic Telescope ARray (NuSTAR)",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "NuSTAR, X-ray, Satellite",
"note": "This work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (USA). This material is based upon work supported by NASA under award number 80GSFC21M0002. We thank Murray Brightman, Renee Ludlam, Guglielmo Mastroserio, and Riley Connors for performing the case study re-analyses in \u00a77.2.\n\nSubmitted - 2110.11522.pdf
",
"abstract": "We present here the updated calibration of The Nuclear Spectroscopic Telescope ARray NuSTAR, which was performed using data on the Crab accumulated over the last 9 years in orbit. The basis for this new calibration contains over 250ks of focused Crab (imaged through the optics) and over 500ks of stray-light Crab (not imaged through optics). We measured an epoch averaged Crab spectrum of the stray-light Crab data and define a canonical Crab spectrum of \u0393 = 2.103 \u00b1 0.001 and N = 9.69 \u00b1 0.02 keV\u207b\u00b9 cm\u207b\u00b2 s\u207b\u00b9 at 1 keV, which we use as our calibration standard. The new calibration, released in the CALDB update 20211020, provides significant updates to: 1) the detector absorption component, 2) the detector response function, and 3) the effective area vignetting function. The calibration improves agreement between FPMA and FPMB across detectors with a standard deviation of 1.7% for repeat observations between off-axis angles of 1-4 arcmin, and the measured flux has increased by 5-15%, with 5% below 1 arcmin off-axis angle, 10% between 1-2 arcmin, and 15 above 4arcmin.",
"date": "2021-10-21",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20220113-182222694",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182222694",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA",
"grant_number": "80GSFC21M0002"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.48550/arXiv.2110.11522",
"primary_object": {
"basename": "2110.11522.pdf",
"url": "https://authors.library.caltech.edu/records/yqpbf-qmh66/files/2110.11522.pdf"
},
"pub_year": "2021",
"author_list": "Madsen, Kristin K.; Forster, Karl; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nh2bc-r2h95",
"eprint_id": 107349,
"eprint_status": "archive",
"datestamp": "2023-08-22 11:37:41",
"lastmod": "2026-03-29 21:30:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Yao-Yuhan",
"name": {
"family": "Yao",
"given": "Yuhan"
},
"orcid": "0000-0001-6747-8509"
},
{
"id": "Kulkarni-S-R",
"name": {
"family": "Kulkarni",
"given": "S. R."
},
"orcid": "0000-0001-5390-8563"
},
{
"id": "Gendreau-Keith-C",
"name": {
"family": "Gendreau",
"given": "K. C."
},
"orcid": "0000-0001-7115-2819"
},
{
"id": "Jaisawal-Gaurava-K",
"name": {
"family": "Jaisawal",
"given": "Gaurava K."
},
"orcid": "0000-0002-6789-2723"
},
{
"id": "Enoto-Teruaki",
"name": {
"family": "Enoto",
"given": "Teruaki"
},
"orcid": "0000-0003-1244-3100"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Marshall-Herman-L",
"name": {
"family": "Marshall",
"given": "Herman L."
},
"orcid": "0000-0002-6492-1293"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Ng-Mason",
"name": {
"family": "Ng",
"given": "Mason"
},
"orcid": "0000-0002-0940-6563"
},
{
"id": "Zhang-Liang-ASTROPHYSICS",
"name": {
"family": "Zhang",
"given": "Liang"
},
"orcid": "0000-0003-4498-9925"
},
{
"id": "Altamirano-Diego",
"name": {
"family": "Altamirano",
"given": "Diego"
},
"orcid": "0000-0002-3422-0074"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Cenko-S-Bradley",
"name": {
"family": "Cenko",
"given": "S. Bradley"
},
"orcid": "0000-0003-1673-970X"
},
{
"id": "Remillard-Ronald-A",
"name": {
"family": "Remillard",
"given": "Ronald A."
},
"orcid": "0000-0003-4815-0481"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Negoro-Hitoshi",
"name": {
"family": "Negoro",
"given": "Hitoshi"
},
"orcid": "0000-0003-0939-1178"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Lien-Amy",
"name": {
"family": "Lien",
"given": "Amy"
},
"orcid": "0000-0002-7851-9756"
},
{
"id": "Wolff-Michael-T",
"name": {
"family": "Wolff",
"given": "Michael T."
},
"orcid": "0000-0002-4013-5650"
},
{
"id": "Ray-Paul-S",
"name": {
"family": "Ray",
"given": "Paul S."
},
"orcid": "0000-0002-5297-5278"
},
{
"id": "Mukai-Koji",
"name": {
"family": "Mukai",
"given": "Koji"
}
},
{
"id": "Wadiasingh-Zorawar",
"name": {
"family": "Wadiasingh",
"given": "Zorawar"
},
"orcid": "0000-0002-9249-0515"
},
{
"id": "Arzoumanian-Zaven",
"name": {
"family": "Arzoumanian",
"given": "Zaven"
}
},
{
"id": "Kawai-Nobuyki",
"name": {
"family": "Kawai",
"given": "Nobuyki"
},
"orcid": "0000-0001-9656-0261"
},
{
"id": "Mihara-Tatehiro",
"name": {
"family": "Mihara",
"given": "Tatehiro"
},
"orcid": "0000-0002-6337-7943"
},
{
"id": "Strohmayer-Tod-E",
"name": {
"family": "Strohmayer",
"given": "Tod E."
},
"orcid": "0000-0001-7681-5845"
}
]
},
"title": "A Comprehensive X-Ray Report on AT2019wey",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Black holes; Low-mass x-ray binary stars; X-ray transient sources; Transient sources; X-ray sources; X-ray binary stars",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 November 30; revised 2021 April 6; accepted 2021 April 14; published 2021 October 21. \n\nWe thank the anonymous reviewer for providing comments that have largely improved this manuscript. We thank Belinda Wilkes and Patrick Slane for allocating DD time on Chandra, and Fiona Harrison for allocating NuSTAR DD time. We thank Kumiko Morihana for providing the cleaned MAXI light curve of MAXI J1305\u2212704. Y.Y. thanks the Heising-Simons Foundation for support. R.M.L. acknowledges the support of NASA through the Hubble Fellowship Program grant HST-HF2-51440.001. J.A.G. acknowledges support from NASA grant 80NSSC17K0515 and from the Alexander von Humboldt Foundation. Z.W. acknowledges support from the NASA postdoctoral program. NICER research at NRL is supported by NASA. This work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (nustardas), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. \n\nFacilities: NICER - , NuSTAR - , CXO (ACIS-S) - , Swift (XRT - , BAT) - , MAXI. - \n\nSoftware: astropy (Astropy Collaboration et al. 2013), CIAO (Fruscione et al. 2006), HEASoft (v6.27; Heasarc 2014), HENDRICS (Bachetti 2015), isis (Houck & Denicola 2000), matplotlib (Hunter 2007), pandas (McKinney 2010), PRESTO (Ransom 2011); relxill (v1.3.10; Garc\u00eda et al. 2014; Dauser et al. 2014) Stingray (Huppenkothen et al. 2019), xspec (v12.11.0; Arnaud 1996).\n\nPublished - Yao_2021_ApJ_920_121.pdf
Submitted - 2012.00160.pdf
",
"abstract": "Here, we present MAXI, Swift, NICER, NuSTAR, and Chandra observations of the X-ray transient AT2019wey (SRGA J043520.9+552226, SRGE J043523.3+552234). From spectral and timing analyses we classify it as a Galactic low-mass X-ray binary (LMXB) with a black hole (BH) or neutron star (NS) accretor. AT2019wey stayed in the low/hard state (LHS) from 2019 December to 2020 August 21, and the hard-intermediate state (HIMS) from 2020 August 21 to 2020 November. For the first six months of the LHS, AT2019wey had a flux of \u223c1 mCrab, and displayed a power-law X-ray spectrum with photon index \u0393 = 1.8. From 2020 June to August, it brightened to \u223c20 mCrab. Spectral features characteristic of relativistic reflection became prominent. On 2020 August 21, the source left the \"hard line\" on the rms\u2013intensity diagram, and transitioned from LHS to HIMS. The thermal disk component became comparable to the power-law component. A low-frequency quasi-periodic oscillation (QPO) was observed. The QPO central frequency increased as the spectrum softened. No evidence of pulsation was detected. We are not able to decisively determine the nature of the accretor (BH or NS). However, the BH option is favored by the position of this source on the \u0393\u2013L_X, L_(radio)\u2013L_X, and L_(opt)\u2013L_X diagrams. We find the BH candidate XTE J1752\u2212223 to be an analog of AT2019wey. Both systems display outbursts with long plateau phases in the hard states. We conclude by noting the potential of SRG in finding new members of this emerging class of low luminosity and long-duration LMXB outbursts.",
"date": "2021-10-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "920",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 121",
"id_number": "CaltechAUTHORS:20210106-131324406",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210106-131324406",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Heising-Simons Foundation"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Einstein Fellowship"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Division-of-Geological-and-Planetary-Sciences"
}
]
},
"doi": "10.3847/1538-4357/ac15f8",
"primary_object": {
"basename": "2012.00160.pdf",
"url": "https://authors.library.caltech.edu/records/nh2bc-r2h95/files/2012.00160.pdf"
},
"related_objects": [
{
"basename": "Yao_2021_ApJ_920_121.pdf",
"url": "https://authors.library.caltech.edu/records/nh2bc-r2h95/files/Yao_2021_ApJ_920_121.pdf"
}
],
"pub_year": "2021",
"author_list": "Yao, Yuhan; Kulkarni, S. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xktc6-ye024",
"eprint_id": 111882,
"eprint_status": "archive",
"datestamp": "2023-08-22 11:38:24",
"lastmod": "2026-03-29 13:55:55",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lario-David",
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"id": "Richardson-Ian-G",
"name": {
"family": "Richardson",
"given": "I. G."
},
"orcid": "0000-0002-3855-3634"
},
{
"id": "Palmerio-Erika",
"name": {
"family": "Palmerio",
"given": "E."
},
"orcid": "0000-0001-6590-3479"
},
{
"id": "Lugaz-No\u00e9",
"name": {
"family": "Lugaz",
"given": "N."
},
"orcid": "0000-0002-1890-6156"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Stevens-Michael-L",
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Szabo-Adam",
"name": {
"family": "Szabo",
"given": "A."
},
"orcid": "0000-0003-3255-9071"
},
{
"id": "Nieves-Chinchilla-Teresa",
"name": {
"family": "Nieves-Chinchilla",
"given": "T."
},
"orcid": "0000-0003-0565-4890"
},
{
"id": "Wilson-Lynn-B-III",
"name": {
"family": "Wilson",
"given": "L. B., III"
},
"orcid": "0000-0002-4313-1970"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Comparative Analysis of the 2020 November 29 Solar Energetic Particle Event Observed by Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Interplanetary shocks; Solar coronal mass ejections; Interplanetary magnetic fields",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 June 17; revised 2021 July 10; accepted 2021 July 15; published 2021 October 21. \n\nD.L. and I.G.R. acknowledge support from NASA Living With a Star (LWS) programs NNH17ZDA001N-LWS and NNH19ZDA001N-LWS and the Goddard Space Flight Center Internal Scientist Funding Model (competitive work package) program. I.G.R. also acknowledges support from the ACE mission. E.P. acknowledges the NASA LWS Jack Eddy Postdoctoral Fellowship Program, administered by UCAR's Cooperative Programs for the Advancement of Earth System Science (CPAESS) under award no. NNX16AK22G. C.M.S.C., J.G., D.G.M., E.R.C., M.E.H., D.J.M, R.L.M., N.A.S., and M.E.W. were supported as a part of the Integrated Science Investigations of the Sun on NASAs Parker Solar Probe mission, under contract NNN06AA01C. The IS\u2299IS data and visualization tools are available to the community at : spacephysics.princeton.edu/missions-instruments/isois. We acknowledge the NASA Parker Solar Probe mission team and the SWEAP team led by J.C. Kasper, the IS\u2299IS team led by D.J. McComas, and the FIELDS team led by S.D. Bale, for the use of PSP data. The data used in this paper can be downloaded from spdf.gsfc.nasa.gov, spp-isois.sr.unh.edu/data_public/EPIHi/level2/, and www.srl.caltech.edu/ACE/ASC/. Search mode data during the Bastille Day event were provided by R.M. Skoug (private communication). Parker Solar Probe was designed, built, and is now operated by The Johns Hopkins University Applied Physics Laboratory as part of NASA's LWS program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We acknowledge all of the science instrument teams for making their data used in this paper available.\n\nPublished - Lario_2021_ApJ_920_123.pdf
",
"abstract": "We analyze two specific features of the intense solar energetic particle (SEP) event observed by Parker Solar Probe (PSP) between 2020 November 29 and 2020 December 2. The interplanetary counterpart of the coronal mass ejection (CME) on 2020 November 29 that generated the SEP event (hereafter ICME-2) arrived at PSP (located at 0.8 au from the Sun) on 2020 December 1. ICME-2 was preceded by the passage of an interplanetary shock at 18:35 UT on 2020 November 30 (hereafter S2), that in turn was preceded by another ICME (i.e., ICME-1) observed in situ on 2020 November 30. The two interesting features of this SEP event at PSP are the following: First, the presence of the intervening ICME-1 affected the evolution of the \u22728 MeV proton intensity-time profiles resulting in the observation of inverted energy spectra throughout the passage of ICME-1. Second, the sheath region preceding ICME-2 was characterized by weak magnetic fields compared to those measured immediately after the passage of the shock S2 and during the passage of ICME-2. Comparison with prior SEP events measured at 1 au but with similar characteristics indicates that (1) low-energy particles accelerated by S2 were excluded from propagating throughout ICME-1, and (2) the low magnetic fields measured in the sheath of ICME-2 resulted from the properties of the upstream solar wind encountered by ICME-2 that was propagated into the sheath, whereas the energy density of the high-energy particles in the sheath did not play a dominant role in the formation of these low magnetic fields.",
"date": "2021-10-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "920",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 123",
"id_number": "CaltechAUTHORS:20211115-235912766",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211115-235912766",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH17ZDA001N-LWS"
},
{
"agency": "NASA",
"grant_number": "NNH19ZDA001N-LWS"
},
{
"agency": "Goddard Space Flight Center"
},
{
"agency": "NASA Postdoctoral Program",
"grant_number": "NNX16AK22G"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac157f",
"primary_object": {
"basename": "Lario_2021_ApJ_920_123.pdf",
"url": "https://authors.library.caltech.edu/records/xktc6-ye024/files/Lario_2021_ApJ_920_123.pdf"
},
"pub_year": "2021",
"author_list": "Lario, D.; Richardson, I. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/q9mh3-qgs37",
"eprint_id": 111437,
"eprint_status": "archive",
"datestamp": "2023-08-20 05:27:36",
"lastmod": "2026-03-28 23:12:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Richardson-John-D",
"name": {
"family": "Richardson",
"given": "J. D."
},
"orcid": "0000-0003-4041-7540"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Burlaga-Leonard-F",
"name": {
"family": "Burlaga",
"given": "L. F."
},
"orcid": "0000-0002-5569-1553"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Opher-Merav",
"name": {
"family": "Opher",
"given": "M."
},
"orcid": "0000-0002-8767-8273"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
}
]
},
"title": "Using Magnetic Flux Conservation to Determine Heliosheath Speeds",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliosheath",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 July 18; revised 2021 September 14; accepted 2021 September 15; published 2021 October 4. \n\nJ.D.R. was supported under NASA contract 959203 from the Jet Propulsion Laboratory to the Massachusetts Institute of Technology and by grants 2019-064 (UAH) and SUB000318 (IMAP). J.D.R., M.O., and A.C.C. acknowledge support from NASA grant 18-DRIVE18_2-0029, Our Heliospheric Shield, 80NSSC20K0603. A.C.C. and E.C.S. were supported under NASA award number NNN12AA01C. L.F.B. is supported by NASA contract #80GSFC19C0012.\n\nPublished - Richardson_2021_ApJL_919_L28.pdf
",
"abstract": "The heliosheath (HSH) radial speeds at Voyager 2 (V2) derived from the plasma instrument (PLS) and from particle instruments using the Compton\u2013Getting (CG) effect are different. At V2 the CG speeds are more variable than the plasma speeds and decrease about 2 yr before the heliopause. We use magnetic flux conservation to differentiate between these two speed profiles at V2, comparing the magnetic flux observed at 1 au and in the HSH. For V2 the PLS speed profile is significantly more consistent with magnetic flux conservation than the CG speeds. For Voyager 1 (V1), we present new V_R derivations from the Cosmic Ray Subsystem (CRS) using the CG method that agree reasonably well with those previously obtained from the low energy charged particle (LECP) instrument. If we use the V2 PLS speed profile to calculate the magnetic flux at V1, we again find much better agreement than if we use the V1 CG speeds. These results suggest that the radial speeds derived from particle anisotropy observations in the HSH are not reliable.",
"date": "2021-10-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "919",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L28",
"id_number": "CaltechAUTHORS:20211014-170555669",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211014-170555669",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "JPL",
"grant_number": "959203"
},
{
"agency": "NASA",
"grant_number": "2019-064"
},
{
"agency": "NASA",
"grant_number": "SUB000318"
},
{
"agency": "NASA",
"grant_number": "18-DRIVE18_2-0029"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0603"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "NASA",
"grant_number": "80GSFC19C0012"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/ac27b1",
"primary_object": {
"basename": "Richardson_2021_ApJL_919_L28.pdf",
"url": "https://authors.library.caltech.edu/records/q9mh3-qgs37/files/Richardson_2021_ApJL_919_L28.pdf"
},
"pub_year": "2021",
"author_list": "Richardson, J. D.; Cummings, A. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2zgxm-s0d62",
"eprint_id": 111362,
"eprint_status": "archive",
"datestamp": "2023-08-20 05:21:08",
"lastmod": "2025-06-30 18:12:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Abuter-R",
"name": {
"family": "Abuter",
"given": "R."
}
},
{
"name": {
"family": "Amorim",
"given": "A."
},
"orcid": "0000-0003-0638-2321"
},
{
"name": {
"family": "Baub\u00f6ck",
"given": "M."
}
},
{
"name": {
"family": "Baganoff",
"given": "F."
},
"orcid": "0000-0003-3852-6545"
},
{
"name": {
"family": "Berger",
"given": "J. P."
},
"orcid": "0000-0001-5025-0428"
},
{
"name": {
"family": "Boyce",
"given": "H."
},
"orcid": "0000-0002-6530-5783"
},
{
"name": {
"family": "Bonnet",
"given": "H."
}
},
{
"name": {
"family": "Brandner",
"given": "W."
},
"orcid": "0000-0003-1939-6351"
},
{
"name": {
"family": "Cl\u00e9net",
"given": "Y."
},
"orcid": "0000-0002-8382-2020"
},
{
"name": {
"family": "Davies",
"given": "R."
}
},
{
"name": {
"family": "de Zeeuw",
"given": "P. T."
},
"orcid": "0000-0003-4175-3474"
},
{
"name": {
"family": "Dexter",
"given": "J."
},
"orcid": "0000-0003-3903-0373"
},
{
"name": {
"family": "Dallilar",
"given": "Y."
}
},
{
"name": {
"family": "Drescher",
"given": "A."
}
},
{
"name": {
"family": "Eckart",
"given": "A."
},
"orcid": "0000-0001-6049-3132"
},
{
"name": {
"family": "Eisenhauer",
"given": "F."
}
},
{
"name": {
"family": "Fazio",
"given": "G. G."
},
"orcid": "0000-0002-0670-0708"
},
{
"name": {
"family": "F\u00f6rster Schreiber",
"given": "N. M."
},
"orcid": "0000-0003-4264-3381"
},
{
"id": "Foster-Karl",
"name": {
"family": "Foster",
"given": "K."
}
},
{
"name": {
"family": "Gammie",
"given": "C."
},
"orcid": "0000-0001-7451-8935"
},
{
"name": {
"family": "Garcia",
"given": "P."
},
"orcid": "0000-0002-1678-3535"
},
{
"name": {
"family": "Gao",
"given": "F."
},
"orcid": "0000-0002-2581-9114"
},
{
"name": {
"family": "Gendron",
"given": "E."
}
},
{
"name": {
"family": "Genzel",
"given": "R."
},
"orcid": "0000-0002-2767-9653"
},
{
"name": {
"family": "Ghisellini",
"given": "G."
},
"orcid": "0000-0001-8949-178X"
},
{
"name": {
"family": "Gillessen",
"given": "S."
},
"orcid": "0000-0002-5708-0481"
},
{
"name": {
"family": "Gurwell",
"given": "M. A."
},
"orcid": "0000-0003-0685-3621"
},
{
"name": {
"family": "Habibi",
"given": "M."
}
},
{
"name": {
"family": "Haggard",
"given": "D."
},
"orcid": "0000-0001-6803-2138"
},
{
"name": {
"family": "Hailey",
"given": "C."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Haubois",
"given": "X."
},
"orcid": "0000-0001-7878-7278"
},
{
"name": {
"family": "Hei\u00dfel",
"given": "G."
},
"orcid": "0000-0003-4965-856X"
},
{
"name": {
"family": "Henning",
"given": "T."
},
"orcid": "0000-0002-1493-300X"
},
{
"name": {
"family": "Hippler",
"given": "S."
},
"orcid": "0000-0002-3912-6108"
},
{
"name": {
"family": "Hora",
"given": "J. L."
},
"orcid": "0000-0002-5599-4650"
},
{
"name": {
"family": "Horrobin",
"given": "M."
},
"orcid": "0000-0001-5451-7847"
},
{
"name": {
"family": "Jim\u00e9nez-Rosales",
"given": "A."
},
"orcid": "0000-0002-2662-3754"
},
{
"name": {
"family": "Jochum",
"given": "L."
}
},
{
"name": {
"family": "Jocou",
"given": "L."
},
"orcid": "0000-0001-9376-1818"
},
{
"name": {
"family": "Kaufer",
"given": "A."
},
"orcid": "0000-0002-5270-3686"
},
{
"name": {
"family": "Kervella",
"given": "P."
},
"orcid": "0000-0003-0626-1749"
},
{
"name": {
"family": "Lacour",
"given": "S."
},
"orcid": "0000-0002-6948-0263"
},
{
"name": {
"family": "Lapeyr\u00e8re",
"given": "V."
}
},
{
"name": {
"family": "Le Bouquin",
"given": "J.-B."
},
"orcid": "0000-0002-0493-4674"
},
{
"name": {
"family": "L\u00e9na",
"given": "P."
},
"orcid": "0000-0002-9091-3051"
},
{
"id": "Lowrance-Patrick-J",
"name": {
"family": "Lowrance",
"given": "P. J."
},
"orcid": "0000-0001-8014-0270"
},
{
"name": {
"family": "Lutz",
"given": "D."
},
"orcid": "0000-0003-0291-9582"
},
{
"name": {
"family": "Markoff",
"given": "S."
},
"orcid": "0000-0001-9564-0876"
},
{
"name": {
"family": "Mori",
"given": "K."
},
"orcid": "0000-0002-9709-5389"
},
{
"name": {
"family": "Morris",
"given": "M. R."
},
"orcid": "0000-0002-6753-2066"
},
{
"name": {
"family": "Neilsen",
"given": "J."
},
"orcid": "0000-0002-8247-786X"
},
{
"name": {
"family": "Nowak",
"given": "M."
},
"orcid": "0000-0001-6923-1315"
},
{
"name": {
"family": "Ott",
"given": "T."
},
"orcid": "0000-0003-1572-0396"
},
{
"name": {
"family": "Paumard",
"given": "T."
},
"orcid": "0000-0003-0655-0452"
},
{
"name": {
"family": "Perraut",
"given": "K."
},
"orcid": "0000-0003-3099-757X"
},
{
"name": {
"family": "Perrin",
"given": "G."
},
"orcid": "0000-0003-0680-0167"
},
{
"name": {
"family": "Ponti",
"given": "G."
},
"orcid": "0000-0003-0293-3608"
},
{
"name": {
"family": "Pfuhl",
"given": "O."
}
},
{
"name": {
"family": "Rabien",
"given": "S."
}
},
{
"name": {
"family": "Rodr\u00edguez-Coira",
"given": "G."
},
"orcid": "0000-0002-4177-6433"
},
{
"name": {
"family": "Shangguan",
"given": "J."
},
"orcid": "0000-0002-4569-9009"
},
{
"name": {
"family": "Shimizu",
"given": "T."
},
"orcid": "0000-0002-2125-4670"
},
{
"name": {
"family": "Scheithauer",
"given": "S."
}
},
{
"name": {
"family": "Smith",
"given": "H. A."
}
},
{
"name": {
"family": "Stadler",
"given": "J."
},
"orcid": "0000-0001-5888-023X"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D. K."
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Straub",
"given": "O."
},
"orcid": "0000-0001-5755-0677"
},
{
"name": {
"family": "Straubmeier",
"given": "C."
},
"orcid": "0000-0002-0671-9302"
},
{
"name": {
"family": "Sturm",
"given": "E."
},
"orcid": "0000-0002-0018-3666"
},
{
"name": {
"family": "Tacconi",
"given": "L. J."
},
"orcid": "0000-0002-1485-9401"
},
{
"name": {
"family": "Vincent",
"given": "F."
},
"orcid": "0000-0002-3855-0708"
},
{
"name": {
"family": "von Fellenberg",
"given": "S. D."
},
"orcid": "0000-0002-9156-2249"
},
{
"name": {
"family": "Waisberg",
"given": "I."
}
},
{
"name": {
"family": "Widmann",
"given": "F."
},
"orcid": "0000-0002-0327-6585"
},
{
"name": {
"family": "Wieprecht",
"given": "E."
}
},
{
"name": {
"family": "Wiezorrek",
"given": "E."
}
},
{
"name": {
"family": "Willner",
"given": "S. P."
},
"orcid": "0000-0002-9895-5758"
},
{
"name": {
"family": "Witzel",
"given": "G."
},
"orcid": "0000-0003-2618-797X"
},
{
"name": {
"family": "Woillez",
"given": "J."
},
"orcid": "0000-0002-2958-4738"
},
{
"name": {
"family": "Yazici",
"given": "S."
}
},
{
"name": {
"family": "Young",
"given": "A."
}
},
{
"name": {
"family": "Zhang",
"given": "S."
},
"orcid": "0000-0002-2967-790X"
},
{
"name": {
"family": "Zins",
"given": "G."
},
"orcid": "0000-0001-8862-7702"
}
]
},
"title": "Constraining particle acceleration in Sgr A\u22c6 with simultaneous GRAVITY, Spitzer, NuSTAR, and Chandra observations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galaxy: center \u2013 accretion, accretion disks \u2013 black hole physics",
"note": "\u00a9 GRAVITY Collaboration 2021. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0),\nwhich permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nReceived 1 April 2021; Accepted 1 July 2021; Published online 05 October 2021. \n\nGRAVITY is developed in a Collaboration by the Max Planck Institute for extraterrestrial Physics, LESIA of Observatoire de Paris/Universit\u00e9 PSL/CNRS/Sorbonne Universit\u00e9/Universit\u00e9 de Paris and IPAG of Universit\u00e9 Grenoble Alpes/CNRS, the Max Planck Institute for Astronomy, the University of Cologne, the CENTRA \u2013 Centro de Astrofisica e Gravita\u00e7\u00e3o, and the European Southern Observatory. \n\nSvF thanks Giulia Focchi for her contribution to the H-band acquisition camera pipeline. SvF, and FW acknowledge support by the Max Planck International Research School. GP is supported by the H2020 ERC Consolidator Grant Hot Milk under grant agreement Nr. 865637. A.A. and P.G. were supported by Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, with grants reference UIDB/00099/2020 and SFRH/BSAB/142940/2018. This work is based in part on observations made with the Spitzer Space Telescope, which was operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA. The scientific results reported in this article are based in part on observations made by the Chandra X-ray Observatory. This work is based in part on observations made with NuSTAR, which is operated by NASA/JPL-Caltech. GGF, JLH, HAS, and SPW acknowledge support for this work from the NASA ADAP program under NASA grant 80NSSC18K0416.\n\nPublished - aa40981-21.pdf
Accepted Version - 2107.01096.pdf
",
"abstract": "We report the time-resolved spectral analysis of a bright near-infrared and moderate X-ray flare of Sgr A\u22c6. We obtained light curves in the M, K, and H bands in the mid- and near-infrared and in the 2 \u2212 8 keV and 2 \u2212 70 keV bands in the X-ray. The observed spectral slope in the near-infrared band is \u03bdL_\u03bd\u2004\u221d\u2004\u03bd^(0.5 \u00b1 0.2); the spectral slope observed in the X-ray band is \u03bdL_\u03bd\u2004\u221d\u2004\u03bd^(\u22120.7 \u00b1 0.5). Using a fast numerical implementation of a synchrotron sphere with a constant radius, magnetic field, and electron density (i.e., a one-zone model), we tested various synchrotron and synchrotron self-Compton scenarios. The observed near-infrared brightness and X-ray faintness, together with the observed spectral slopes, pose challenges for all models explored. We rule out a scenario in which the near-infrared emission is synchrotron emission and the X-ray emission is synchrotron self-Compton. Two realizations of the one-zone model can explain the observed flare and its temporal correlation: one-zone model in which the near-infrared and X-ray luminosity are produced by synchrotron self-Compton and a model in which the luminosity stems from a cooled synchrotron spectrum. Both models can describe the mean spectral energy distribution (SED) and temporal evolution similarly well. In order to describe the mean SED, both models require specific values of the maximum Lorentz factor \u03b3_(max), which differ by roughly two orders of magnitude. The synchrotron self-Compton model suggests that electrons are accelerated to \u03b3_(max)\u2004\u223c\u2004500, while cooled synchrotron model requires acceleration up to \u03b3_(max)\u2004\u223c\u20045 \u00d7 10\u2074. The synchrotron self-Compton scenario requires electron densities of 10\u00b9\u2070 cm\u207b\u00b3 that are much larger than typical ambient densities in the accretion flow. Furthermore, it requires a variation of the particle density that is inconsistent with the average mass-flow rate inferred from polarization measurements and can therefore only be realized in an extraordinary accretion event. In contrast, assuming a source size of 1\u2006R_S, the cooled synchrotron scenario can be realized with densities and magnetic fields comparable with the ambient accretion flow. For both models, the temporal evolution is regulated through the maximum acceleration factor \u03b3_(max), implying that sustained particle acceleration is required to explain at least a part of the temporal evolution of the flare.",
"date": "2021-10",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "654",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A22",
"id_number": "CaltechAUTHORS:20211011-220006826",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211011-220006826",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "International Max Planck Research School (IMPRS) for Astronomy and Astrophysics"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "865637"
},
{
"agency": "Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT)",
"grant_number": "UIDB/00099/2020"
},
{
"agency": "Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT)",
"grant_number": "SFRH/BSAB/142940/2018"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0416"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"corp_creators": {
"items": [
"GRAVITY Collaboration"
]
},
"doi": "10.1051/0004-6361/202140981",
"primary_object": {
"basename": "2107.01096.pdf",
"url": "https://authors.library.caltech.edu/records/2zgxm-s0d62/files/2107.01096.pdf"
},
"related_objects": [
{
"basename": "aa40981-21.pdf",
"url": "https://authors.library.caltech.edu/records/2zgxm-s0d62/files/aa40981-21.pdf"
}
],
"pub_year": "2021",
"author_list": "Abuter, R.; Amorim, A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jvp1g-21v48",
"eprint_id": 111552,
"eprint_status": "archive",
"datestamp": "2023-08-20 05:21:40",
"lastmod": "2026-03-28 21:10:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Ingram-Adam",
"name": {
"family": "Ingram",
"given": "Adam"
},
"orcid": "0000-0002-5311-9078"
},
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "van-der-Klis-Michiel",
"name": {
"family": "van der Klis",
"given": "Michiel"
},
"orcid": "0000-0003-0070-9872"
},
{
"id": "Cavecchi-Yuri",
"name": {
"family": "Cavecchi",
"given": "Yuri"
},
"orcid": "0000-0002-6447-3603"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley"
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "K\u00f6nig-Ole",
"name": {
"family": "K\u00f6nig",
"given": "Ole"
}
},
{
"id": "Lucchini-Matteo",
"name": {
"family": "Lucchini",
"given": "Matteo"
},
"orcid": "0000-0002-2235-3347"
}
]
},
"title": "Modelling correlated variability in accreting black holes: the effect of high density and variable ionization on reverberation lags",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013 black hole physics \u2013 relativistic processes \u2013 X-rays: binaries \u2013 X-rays: galaxies",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2021 July 11. Received 2021 July 8; in original form 2021 March 12. Published: 21 July 2021. \n\nThe authors would like to acknowledge the anonymous referee for the very helpful comments and suggestions. GM, JW, EK, and JAG acknowledge support from the NASA grant 80NSSC17K0515. AI acknowledges support from the Royal Society. MK thanks the support from NWO Spinoza. JAG thanks support from the Alexander von Humboldt Foundation. This work was partially supported under NASA contract No. NNG08FD60C. \n\nData Availability: The source code for the model described in this paper will soon be made publicly available in the form of an update to the RELTRANS model package (https://adingram.bitbucket.io/reltrans.html). The NICER observation is publicly available at the HEASOFT webpage.\n\nPublished - stab2056.pdf
Accepted Version - 2107.06893.pdf
",
"abstract": "We present a new release of the RELTRANS model to fit the complex cross-spectrum of accreting black holes as a function of energy. The model accounts for continuum lags and reverberation lags self-consistently in order to consider the widest possible range of X-ray variability time-scales. We introduce a more self-consistent treatment of the reverberation lags, accounting for how the time variations of the illuminating flux change the ionization level of the accretion disc. This process varies the shape of the reflection spectrum in time causing an additional source of lags besides the light crossing delay. We also consider electron densities in the accretion disc up to 10\u00b2\u2070\u2009cm\u207b\u00b3, which are found in most of the stellar mass black holes and in some active galactic nuclei. These high densities increase the amplitude of the reverberation lags below 1 keV since the reflection flux enhances in the same energy range. In addition, we investigate the properties of hard lags produced by variations in the power-law index of the continuum spectrum, which can be interpreted as due to roughly 3 per cent3 per cent variability in the corona's optical depth and temperature. As a test case, we simultaneously fit the lag-energy spectra in a wide range of Fourier frequency for the black hole candidate MAXI J1820+0701820 observed with NICER. The best fit shows how the reverberation lags contribute even at the longer time-scales where the hard lags are important. This proves the importance of modelling these two lags together and self-consistently in order to constrain the parameters of the system.",
"date": "2021-10",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "507",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "55-73",
"id_number": "CaltechAUTHORS:20211020-164833304",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211020-164833304",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "Royal Society"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stab2056",
"primary_object": {
"basename": "2107.06893.pdf",
"url": "https://authors.library.caltech.edu/records/jvp1g-21v48/files/2107.06893.pdf"
},
"related_objects": [
{
"basename": "stab2056.pdf",
"url": "https://authors.library.caltech.edu/records/jvp1g-21v48/files/stab2056.pdf"
}
],
"pub_year": "2021",
"author_list": "Mastroserio, Guglielmo; Ingram, Adam; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zdnsf-ajx86",
"eprint_id": 110897,
"eprint_status": "archive",
"datestamp": "2023-08-22 11:08:08",
"lastmod": "2026-03-28 22:22:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "Douglas J. K."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Photospheric Radius Expansion and a Double-peaked Type-I X-Ray Burst from GRS 1741.9\u20132853",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Neutron stars; Low-mass x-ray binary stars; X-ray bursts; X-ray sources",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 March 15; revised 2021 June 16; accepted 2021 June 24; published 2021 August 30. \n\nJ.J. acknowledges support by the Tsinghua Astrophysics Outstanding (TAO) Fellowship and the Tsinghua Shuimu Scholar Programme. R.M.L. acknowledges the support of NASA through Hubble Fellowship Program grant HST-HF2-51440.001. D.J.K.B. acknowledges support from the Royal Society. J.A.G. acknowledges support from NASA ATP grant 80NSSC20K0540 and from the Alexander von Humboldt Foundation. This work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We would also like to acknowledge the insightful feedback provided by the reviewer, which significantly improved the quality of this work. \n\nSoftware: Astropy, DS9, Scipy, Stingray, XSpec.\n\nPublished - Pike_2021_ApJ_918_9.pdf
Accepted Version - 2106.13312.pdf
",
"abstract": "We present an analysis of two type-I X-ray bursts observed by NuSTAR originating from the very faint transient neutron star (NS) low-mass X-ray binary GRS 1741.9\u20132853 during a period of outburst in 2020 May. We show that the persistent emission can be modeled as an absorbed, Comptonized blackbody in addition to Fe K\u03b1 emission, which can be attributed to relativistic disk reflection. We measure a persistent bolometric, unabsorbed luminosity of L_(bol) = 7.03_(-0.05)^(+0.04) x 10\u00b3\u2076 erg s\u207b\u00b9, assuming a distance of 7 kpc, corresponding to an Eddington ratio of 4.5%. This persistent luminosity combined with light-curve analysis leads us to infer that the bursts were the result of pure He burning rather than mixed H/He burning. Time-resolved spectroscopy reveals that the bolometric flux of the first burst exhibits a double-peaked structure, placing the source within a small population of accreting NSs that exhibit multiple-peaked type-I X-ray bursts. We find that the second, brighter burst shows evidence for photospheric radius expansion (PRE) and that at its peak, this PRE event had an unabsorbed bolometric flux of F_(peak) = 2.94_(-0.26)^(+0.28) x 10\u207b\u2078 erg cm\u207b\u00b2 s\u207b\u00b9. This yields a new distance estimate of d = 9.0 \u00b1 0.5 kpc, assuming that this corresponds to the Eddington limit for pure He burning on the surface of a canonical NS. Additionally, we performed a detailed timing analysis that failed to find evidence for quasi-periodic oscillations or burst oscillations, and we place an upper limit of 16% on the rms variability around 589 Hz, the frequency at which oscillations have previously been reported.",
"date": "2021-09-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "918",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 9",
"id_number": "CaltechAUTHORS:20210914-225403760",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210914-225403760",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Tsinghua University"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "Royal Society"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0540"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ac0ef9",
"primary_object": {
"basename": "2106.13312.pdf",
"url": "https://authors.library.caltech.edu/records/zdnsf-ajx86/files/2106.13312.pdf"
},
"related_objects": [
{
"basename": "Pike_2021_ApJ_918_9.pdf",
"url": "https://authors.library.caltech.edu/records/zdnsf-ajx86/files/Pike_2021_ApJ_918_9.pdf"
}
],
"pub_year": "2021",
"author_list": "Pike, Sean N.; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/s29tw-5ty76",
"eprint_id": 111363,
"eprint_status": "archive",
"datestamp": "2023-08-20 04:55:35",
"lastmod": "2026-03-30 07:08:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Gallo-Luigi-C-C",
"name": {
"family": "Gallo",
"given": "L. C."
}
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Nardini-Emanuele",
"name": {
"family": "Nardini",
"given": "E."
},
"orcid": "0000-0001-9226-8992"
},
{
"id": "Reynolds-Christopher-S",
"name": {
"family": "Reynolds",
"given": "C. S."
},
"orcid": "0000-0002-1510-4860"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Kosec-P",
"name": {
"family": "Kosec",
"given": "P."
}
},
{
"id": "Reynolds-Mark-T",
"name": {
"family": "Reynolds",
"given": "M. T."
},
"orcid": "0000-0003-1621-9392"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Miller-Jon-M",
"name": {
"family": "Miller",
"given": "J. M."
}
}
]
},
"title": "Extreme relativistic reflection in the active galaxy ESO\u2009033-G002",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: active \u2013 X-rays: individual: ESO 033-G002",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2021 April 19; Received 2021 April 13; in original form 2021 March 10; Published: 19 July 2021. \n\nDJW acknowledges support from the Science and Technology Facilities Council (STFC) in the form of an Ernest Rutherford Fellowship (ST/N004027/1). MB acknowledges support from the YCAA Prize Postdoctoral Fellowship. CSR thanks the STFC for support under Consolidated Grant ST/S000623/1, as well as the European Research Council (ERC) for support under the European Union's Horizon 2020 research and innovation programme (grant 834203). CR acknowledges support from the FONDECYT Iniciacion grant 11190831. JAG acknowledges support from NASA grant 80NSSC19K1020 and from the Alexander von Humboldt Foundation. This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by the NASA Jet Propulsion Laboratory (JPL), and has utilized the NUSTARDAS software package, jointly developed by the Space Science Data Centre (SSDC; Italy) and Caltech (USA). This research has also made use of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States. This work has made use of the CORNER package (Foreman-Mackey 2016) for data visualization. \n\nData Availability: All of the data underlying this article will be available from June 2021 via ESA's XMM-Newton Science Archive (https://www.cosmos.esa.int/web/xmm-newton/xsa) and NASA's HEASARC archive (https://heasarc.gsfc.nasa.gov/).\n\nPublished - stab1290.pdf
Submitted - 2107.10278.pdf
",
"abstract": "We present the first high signal-to-noise broad-band X-ray spectrum of the radio-quiet type-2 Seyfert ESO\u2009033-G002, combining data from XMM\u2013Newton and NuSTAR. The nuclear X-ray spectrum is complex, showing evidence for both neutral and ionized absorption, as well as reflection from both the accretion disc and more distant material, but our broad-band coverage allows us to disentangle all of these different components. The total neutral column during this epoch is N_H \u223c (5\u22126) \u00d7 10\u00b2\u00b2\u2009cm\u207b\u00b2\u2060, consistent with the optical classification of ESO\u2009033-G002 as a type-2 Seyfert but not so large as to prevent us from robustly determining the properties of the innermost accretion flow. The ionized absorption \u2013 dominated by lines from Fe\u2009XXV and Fe\u2009XXVI \u2013 reveals a moderately rapid outflow (v_(out) \u223c 5400\u2009km s\u207b\u00b9) which has a column comparable to the neutral absorption. We find the disc reflection from the innermost regions to be extreme, with a reflection fraction of R_(frac) \u223c 5. This requires strong gravitational lightbending and, in turn, both an extremely compact corona (within \u223c2\u2009R_G of the black hole) and a rapidly rotating black hole (a* > 0.96). Despite this tight size constraint, with a temperature of kT_e = 40\u201370\u2009keV the X-ray corona in ESO\u2009033-G002 appears similar to other active galactic nucle in terms of its placement in the compactness\u2013temperature plane, consistent with sitting close to the limit determined by runaway pair production. Finally, combining X-ray spectroscopy, timing, and updated optical spectroscopy, we also estimate the mass of the black hole to be log[M_(BH)/M_\u2299] \u223c 7.0\u20137.5.",
"date": "2021-09",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "506",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "1557-1572",
"id_number": "CaltechAUTHORS:20211011-221326133",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211011-221326133",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/N004027/1"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/S000623/1"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "834203"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1020"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/stab1290",
"primary_object": {
"basename": "2107.10278.pdf",
"url": "https://authors.library.caltech.edu/records/s29tw-5ty76/files/2107.10278.pdf"
},
"related_objects": [
{
"basename": "stab1290.pdf",
"url": "https://authors.library.caltech.edu/records/s29tw-5ty76/files/stab1290.pdf"
}
],
"pub_year": "2021",
"author_list": "Walton, D. J.; Balokovi\u0107, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/bj16n-jxc86",
"eprint_id": 93196,
"eprint_status": "archive",
"datestamp": "2023-08-20 04:49:33",
"lastmod": "2026-03-30 08:33:17",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Eikenberry-Stephen-S",
"name": {
"family": "Eikenberry",
"given": "S."
},
"orcid": "0000-0002-1332-5061"
},
{
"id": "Jiang-Y-F",
"name": {
"family": "Jiang",
"given": "Y.-F."
}
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "Fuerst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Marshall-Herman-L",
"name": {
"family": "Marshall",
"given": "H. L."
}
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Altamirano-Diego",
"name": {
"family": "Altamirano",
"given": "D."
},
"orcid": "0000-0002-3422-0074"
},
{
"id": "Bird-A-J",
"name": {
"family": "Bird",
"given": "A. J."
}
},
{
"id": "Perez-G",
"name": {
"family": "Perez",
"given": "G."
}
},
{
"id": "Miller-Jones-James-C-A",
"name": {
"family": "Miller-Jones",
"given": "J. C. A."
},
"orcid": "0000-0003-3124-2814"
},
{
"id": "Charles-P-A",
"name": {
"family": "Charles",
"given": "P. A."
}
},
{
"id": "Boggs-Steven-E",
"name": {
"family": "Boggs",
"given": "S."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-Finn-W",
"name": {
"family": "Christensen",
"given": "F."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-William-W",
"name": {
"family": "Craig",
"given": "W."
}
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "K."
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Hailey-Charles-J",
"name": {
"family": "Hailey",
"given": "C."
}
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zhang-William-W",
"name": {
"family": "Zhang",
"given": "W. W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "NuSTAR reveals the hidden nature of SS433",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013X-rays: binaries",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2021 April 27. Received 2021 April 6; in original form 2020 May 29. Published: 06 May 2021. \n\nThe authors thank the anonymous referee for their valuable suggestions. MJM and DJW appreciate support via STFC Ernest Rutherford Fellowships. WNA is supported by an ESA research fellowship. This research was partially supported by the Australian Government through the Australian Research Council's Discovery Projects funding scheme (project DP200102471). The authors thank Keith Arnaud for useful suggestions. This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). \n\nData Availability: The data underlying this article were accessed from the HEASARC NuSTAR data repository at https://heasarc.gsfc.nasa.gov/docs/archive.html. The derived data generated in this research will be shared on reasonable request to the corresponding author.\n\nPublished - stab1280.pdf
Submitted - 1810.10518.pdf
",
"abstract": "SS433 is the only Galactic binary system known to persistently accrete at highly super-critical (or hyper-critical) rates, similar to those in tidal disruption events, and likely needed to explain the rapid growth of those very high redshift quasars containing massive SMBHs. Probing the inner regions of SS433 in the X-rays is crucial to understanding this system, and super-critical accretion in general, but is highly challenging due to obscuration by the surrounding wind, driven from the accretion flow. NuSTAR observed SS433 in the hard X-ray band across multiple phases of its 162 d superorbital precession period. Spectral-timing tools allow us to infer that the hard X-ray emission from the inner regions is likely being scattered towards us by the walls of the wind-cone. By comparing to numerical models, we determine an intrinsic X-ray luminosity of \u2265 2 \u00d7 10\u00b3\u2077 erg s\u207b\u00b9 and that, if viewed face on, we would infer an apparent luminosity of >1 \u00d7 10\u00b3\u2079 erg s\u207b\u00b9, confirming SS433's long-suspected nature as an ultraluminous X-ray source (ULX). We present the discovery of a narrow, \u223c100 s lag due to atomic processes occurring in outflowing material travelling at least 0.14\u20130.29c, which matches absorption lines seen in ULXs and \u2013 in the future \u2013 will allow us to map a super-critical outflow for the first time.",
"date": "2021-09",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "506",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "1045-1058",
"id_number": "CaltechAUTHORS:20190225-081654781",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190225-081654781",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "Australian Research Council",
"grant_number": "DP200102471"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stab1280",
"primary_object": {
"basename": "1810.10518.pdf",
"url": "https://authors.library.caltech.edu/records/bj16n-jxc86/files/1810.10518.pdf"
},
"related_objects": [
{
"basename": "stab1280.pdf",
"url": "https://authors.library.caltech.edu/records/bj16n-jxc86/files/stab1280.pdf"
}
],
"pub_year": "2021",
"author_list": "Middleton, M. J.; Walton, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z5817-wjw21",
"eprint_id": 110884,
"eprint_status": "archive",
"datestamp": "2023-08-22 10:53:56",
"lastmod": "2026-03-29 17:27:16",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kalita-Boris-S",
"name": {
"family": "Kalita",
"given": "Boris S."
},
"orcid": "0000-0001-9215-7053"
},
{
"id": "Daddi-Emanuele",
"name": {
"family": "Daddi",
"given": "Emanuele"
},
"orcid": "0000-0002-3331-9590"
},
{
"id": "D'Eugenio-Chirara",
"name": {
"family": "D'Eugenio",
"given": "Chiara"
},
"orcid": "0000-0001-7344-3126"
},
{
"id": "Valentino-Francesco-M",
"name": {
"family": "Valentino",
"given": "Francesco"
},
"orcid": "0000-0001-6477-4011"
},
{
"id": "Rich-R-Michael",
"name": {
"family": "Rich",
"given": "R. Michael"
},
"orcid": "0000-0003-0427-8387"
},
{
"id": "G\u00f3mez-Guijarro-Carlos",
"name": {
"family": "G\u00f3mez-Guijarro",
"given": "Carlos"
},
"orcid": "0000-0002-4085-9165"
},
{
"id": "Coogan-Rosemary-T",
"name": {
"family": "Coogan",
"given": "Rosemary T."
},
"orcid": "0000-0002-4343-0479"
},
{
"id": "Delvecchio-Ivan",
"name": {
"family": "Delvecchio",
"given": "Ivan"
},
"orcid": "0000-0001-8706-2252"
},
{
"id": "Elbaz-David",
"name": {
"family": "Elbaz",
"given": "David"
},
"orcid": "0000-0002-7631-647X"
},
{
"id": "Neill-James-D",
"name": {
"family": "Neill",
"given": "James D."
},
"orcid": "0000-0002-0466-1119"
},
{
"id": "Puglisi-Annagrazia",
"name": {
"family": "Puglisi",
"given": "Annagrazia"
},
"orcid": "0000-0001-9369-1805"
},
{
"id": "Strazzullo-Veronica",
"name": {
"family": "Strazzullo",
"given": "Veronica"
},
"orcid": "0000-0001-7975-2894"
}
]
},
"title": "An Ancient Massive Quiescent Galaxy Found in a Gas-rich z \u223c 3 Group",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "High-redshift galaxies; Galaxy evolution; Galaxy groups",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 June 1; revised 2021 July 13; accepted 2021 July 22; published 2021 August 16. \n\nWe would like to express our gratitude to Raphael Gobat for his valuable inputs. We also thank Gabriel Brammer for assistance with the use of grizli for the HST data reduction. R.M.R. and J.D.N. acknowledge support from GO15910. V.S. acknowledges the support from the ERC-StG ClustersXCosmo grant agreement 716762. F.V. acknowledges support from the Carlsberg Foundation Research Grant CF18-0388 \"Galaxies: Rise and Death\" and from the Cosmic Dawn Center of Excellence funded by the Danish National Research Foundation under then grant No. 140. A.P. gratefully acknowledges financial support from STFC through grants ST/T000244/1 and ST/P000541/1. B.S.K. would like to thank William G. Hartley (ETH Zurich, Switzerland), for providing crucial software-related files that were needed for this work. This paper makes use of the following ALMA data: 2019.1.00399. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. \n\nSoftware: SExtractor (Bertin & Arnouts 1996), GALFIT (Peng et al. 2002, 2010), grizli (v0.4.0; Brammer 2018), CASA (McMullin et al. 2007), HYPERZ (Bolzonella et al. 2000).\n\nPublished - Kalita_2021_ApJL_917_L17.pdf
Accepted Version - 2107.13241.pdf
",
"abstract": "Deep Atacama Large Millimeter/submillimeter Array and Hubble Space Telescope observations reveal the presence of a quenched massive galaxy within the z = 2.91 galaxy group RO-1001. With a mass-weighted stellar age of 1.6 \u00b1 0.4 Gyr this galaxy is one of the oldest known at z \u223c 3, implying that most of its 10\u00b9\u00b9 M_\u2299 of stars were rapidly formed at z > 6\u20138. This is a unique example of the predominantly passive evolution of a galaxy over at least 3 < z < 6 following its high-redshift quenching and a smoking-gun event pointing to the early imprint of an age\u2013environment relation. At the same time, being in a dense group environment with extensive cold gas reservoirs as betrayed by a giant Ly\u03b1 halo, the existence of this galaxy demonstrates that gas accretion shutdown is not necessary for quenching and its maintenance.",
"date": "2021-08-20",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "917",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L17",
"id_number": "CaltechAUTHORS:20210914-225354517",
"issn": "2041-8205",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210914-225354517",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "GO15910"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "716762"
},
{
"agency": "Carlsberg Foundation",
"grant_number": "CF18-0388"
},
{
"agency": "Danish National Research Foundation",
"grant_number": "140"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T000244/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/P000541/1"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/ac16dc",
"primary_object": {
"basename": "2107.13241.pdf",
"url": "https://authors.library.caltech.edu/records/z5817-wjw21/files/2107.13241.pdf"
},
"related_objects": [
{
"basename": "Kalita_2021_ApJL_917_L17.pdf",
"url": "https://authors.library.caltech.edu/records/z5817-wjw21/files/Kalita_2021_ApJL_917_L17.pdf"
}
],
"pub_year": "2021",
"author_list": "Kalita, Boris S.; Daddi, Emanuele; et al."
},
{
"id": "https://authors.library.caltech.edu/records/yhs88-g7y78",
"eprint_id": 110261,
"eprint_status": "archive",
"datestamp": "2023-08-22 10:49:12",
"lastmod": "2026-03-29 20:36:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garnavich-Peter",
"name": {
"family": "Garnavich",
"given": "Peter"
},
"orcid": "0000-0003-4069-2817"
},
{
"id": "Littlefield-Colin",
"name": {
"family": "Littlefield",
"given": "Colin"
},
"orcid": "0000-0001-7746-5795"
},
{
"id": "Wagner-R-M",
"name": {
"family": "Wagner",
"given": "R. M."
}
},
{
"id": "van-Roestel-Joannes",
"name": {
"family": "van Roestel",
"given": "Jan"
},
"orcid": "0000-0002-2626-2872"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Szkody-Paula",
"name": {
"family": "Szkody",
"given": "Paula"
},
"orcid": "0000-0003-4373-7777"
},
{
"id": "Thorstensen-John-R",
"name": {
"family": "Thorstensen",
"given": "John R."
},
"orcid": "0000-0002-4964-4144"
}
]
},
"title": "Confirmation of a Second Propeller: A High-inclination Twin of AE Aquarii",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Cataclysmic variable stars; Magnetic stars; White dwarf stars; DQ Herculis stars",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 February 6; revised 2021 May 9; accepted 2021 May 18; published 2021 August 10. \n\nWe thank R. Pogge and O. Kuhn for their help in obtaining the LBT observations. This work is partly based on observations obtained at the MDM Observatory, operated by Dartmouth College, Columbia University, The Ohio State University, Ohio University, and the University of Michigan.\n\nPublished - Garnavich_2021_ApJ_917_22.pdf
Accepted Version - 2102.08377.pdf
",
"abstract": "For decades, AE Aquarii (AE Aqr) has been the only cataclysmic variable star known to contain a magnetic propeller: a persistent outflow whose expulsion from the binary is powered by the spin-down of the rapidly rotating, magnetized white dwarf. In 2020, LAMOST J024048.51+195226.9 (J0240) was identified as a candidate eclipsing AE Aqr object, and we present three epochs of time-series spectroscopy that strongly support this hypothesis. We show that, during the photometric flares noted by Thorstensen, the Balmer and He i emission lines reach velocities of ~3000 km s\u207b\u00b9, well in excess of what is observed in normal cataclysmic variables. This is, however, consistent with the high-velocity emission seen in flares from AE Aqr. Additionally, we confirm beyond doubt that J0240 is a deeply eclipsing system. The flaring continuum, He i and much of the Balmer emission likely originate close to the WD because they disappear during the eclipse that is centered on inferior conjunction of the secondary star. The fraction of the Balmer emission remaining visible during eclipse is likely produced in the extended outflow. Most enticingly of all, this outflow produces a narrow P Cygni absorption component for nearly half of the orbit, and we demonstrate that this scenario closely matches the outflow kinematics predicted by Wynn et al. While an important piece of evidence for the magnetic-propeller hypothesis\u2014a rapid WD spin period\u2014remains elusive, our spectra provide compelling support for the existence of a propeller-driven outflow viewed nearly edge-on, enabling a new means of rigorously testing theories of the propeller phenomenon.",
"date": "2021-08-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "917",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 22",
"id_number": "CaltechAUTHORS:20210813-181203703",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210813-181203703",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "MDM Observatory"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ac0339",
"primary_object": {
"basename": "2102.08377.pdf",
"url": "https://authors.library.caltech.edu/records/yhs88-g7y78/files/2102.08377.pdf"
},
"related_objects": [
{
"basename": "Garnavich_2021_ApJ_917_22.pdf",
"url": "https://authors.library.caltech.edu/records/yhs88-g7y78/files/Garnavich_2021_ApJ_917_22.pdf"
}
],
"pub_year": "2021",
"author_list": "Garnavich, Peter; Littlefield, Colin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/x557p-9vd85",
"eprint_id": 107932,
"eprint_status": "archive",
"datestamp": "2023-08-20 04:24:00",
"lastmod": "2026-03-30 09:02:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Coughlin-Michael-W",
"name": {
"family": "Coughlin",
"given": "Michael W."
},
"orcid": "0000-0002-8262-2924"
},
{
"id": "Burdge-Kevin-B",
"name": {
"family": "Burdge",
"given": "Kevin"
},
"orcid": "0000-0002-7226-836X"
},
{
"id": "Duev-Dmitry-A",
"name": {
"family": "Duev",
"given": "Dmitry A."
},
"orcid": "0000-0001-5060-8733"
},
{
"id": "Katz-Michael-L",
"name": {
"family": "Katz",
"given": "Michael L."
}
},
{
"id": "van-Roestel-Jan",
"name": {
"family": "van Roestel",
"given": "Jan"
},
"orcid": "0000-0002-2626-2872"
},
{
"id": "Drake-Andrew-J",
"name": {
"family": "Drake",
"given": "Andrew"
}
},
{
"id": "Graham-M-J",
"name": {
"family": "Graham",
"given": "Matthew J."
},
"orcid": "0000-0002-3168-0139"
},
{
"id": "Hillenbrand-L-A",
"name": {
"family": "Hillenbrand",
"given": "Lynne"
}
},
{
"id": "Mahabal-Ashish-A",
"name": {
"family": "Mahabal",
"given": "Ashish A."
},
"orcid": "0000-0003-2242-0244"
},
{
"id": "Masci-Frank-J",
"name": {
"family": "Masci",
"given": "Frank J."
},
"orcid": "0000-0002-8532-9395"
},
{
"id": "Mr\u00f3z-Przemek",
"name": {
"family": "Mr\u00f3z",
"given": "Przemek"
},
"orcid": "0000-0001-7016-1692"
},
{
"id": "Prince-T-A",
"name": {
"family": "Prince",
"given": "Thomas A."
},
"orcid": "0000-0002-8850-3627"
},
{
"id": "Yao-Yuhan",
"name": {
"family": "Yao",
"given": "Yuhan"
},
"orcid": "0000-0001-6747-8509"
},
{
"id": "Bellm-Eric-C",
"name": {
"family": "Bellm",
"given": "Eric C."
},
"orcid": "0000-0001-8018-5348"
},
{
"id": "Burruss-Rick-S",
"name": {
"family": "Burruss",
"given": "Rick"
}
},
{
"id": "Dekany-Richard-G",
"name": {
"family": "Dekany",
"given": "Richard"
},
"orcid": "0000-0002-5884-7867"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Kaplan-David-L",
"name": {
"family": "Kaplan",
"given": "David L."
},
"orcid": "0000-0001-6295-2881"
},
{
"id": "Kupfer-Thomas",
"name": {
"family": "Kupfer",
"given": "Thomas"
},
"orcid": "0000-0002-6540-1484"
},
{
"id": "Laher-Russ-R",
"name": {
"family": "Laher",
"given": "Russ R."
},
"orcid": "0000-0003-2451-5482"
},
{
"id": "Riddle-Reed-L",
"name": {
"family": "Riddle",
"given": "Reed"
},
"orcid": "0000-0002-0387-370X"
},
{
"id": "Rigault-Mickael",
"name": {
"family": "Rigault",
"given": "Mickael"
},
"orcid": "0000-0002-8121-2560"
},
{
"id": "Rodriguez-Hector",
"name": {
"family": "Rodriguez",
"given": "Hector"
}
},
{
"id": "Rusholme-Benjamin",
"name": {
"family": "Rusholme",
"given": "Ben"
},
"orcid": "0000-0001-7648-4142"
},
{
"id": "Zolkower-Jeffry-N",
"name": {
"family": "Zolkower",
"given": "Jeffry"
}
}
]
},
"title": "The ZTF Source Classification Project \u2013 II. Periodicity and variability processing metrics",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "methods: data analysis \u2013 techniques: photometric \u2013 catalogues \u2013 surveys \u2013 stars: statistics",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 September 15. Received 2020 September 15; in original form 2020 July 16. Published: 26 May 2021. \n\nThe authors would like to thank our referee, Dr. Aren Heinze, for very useful reports, improving the content of the paper. MWC acknowledges support from the National Science Foundation with grant number PHY-2010970. MLK acknowledges support from the National Science Foundation under grant DGE-0948017 and the Chateaubriand Fellowship from the Office for Science & Technology of the Embassy of France in the United States. MR has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement n759194 - USNAC). DK is supported by NSF grant AST-1816492. \n\nThe authors acknowledge the Minnesota Supercomputing Institute9 (MSI) at the University of Minnesota for providing resources that contributed to the research results reported within this paper under project 'Identification of Variable Objects in the Zwicky Transient Facility.' This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231 under project 'Towards a complete catalog of variable sources to support efficient searches for compact binary mergers and their products.' This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) COMET at SDSU through allocation AST200016. MLK also acknowledges the computational resources and staff contributions provided for the Quest/Grail high performance computing facility at Northwestern University.\n\nBased on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington (UW), Deutsches Elektronen-Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by Caltech Optical Observatories, IPAC, and UW. \n\nData Availability: The data underlying this article are derived from public code found here: https://github.com/mcoughlin/ztfperiodic. DR2, including how to access the data, can be found at https://www.ztf.caltech.edu/page/dr2.\n\nPublished - stab1502.pdf
Submitted - 2009.14071.pdf
",
"abstract": "The current generation of all-sky surveys is rapidly expanding our ability to study variable and transient sources. These surveys, with a variety of sensitivities, cadences, and fields of view, probe many ranges of time-scale and magnitude. Data from the Zwicky Transient Facility (ZTF) yields an opportunity to find variables on time-scales from minutes to months. In this paper, we present the codebase, ztfperiodic, and the computational metrics employed for the catalogue based on ZTF's Second Data Release. We describe the publicly available, graphical-process-unit optimized period-finding algorithms employed, and highlight the benefit of existing and future graphical-process-unit clusters. We show how generating metrics as input to catalogues of this scale is possible for future ZTF data releases. Further work will be needed for future data from the Vera C. Rubin Observatory's Legacy Survey of Space and Time.",
"date": "2021-08",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "505",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2954-2965",
"id_number": "CaltechAUTHORS:20210205-093232236",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210205-093232236",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "PHY-2010970"
},
{
"agency": "NSF Graduate Research Fellowship",
"grant_number": "DGE-0948017"
},
{
"agency": "Office for Science and Technology of the Embassy of France"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "759194"
},
{
"agency": "NSF",
"grant_number": "AST-1816492"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC02-05CH11231"
},
{
"agency": "NSF",
"grant_number": "ACI-1548562"
},
{
"agency": "NSF",
"grant_number": "AST-200016"
},
{
"agency": "NSF",
"grant_number": "AST-1440341"
},
{
"agency": "ZTF partner institutions"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Infrared-Processing-and-Analysis-Center-(IPAC)"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Zwicky-Transient-Facility"
}
]
},
"doi": "10.1093/mnras/stab1502",
"primary_object": {
"basename": "2009.14071.pdf",
"url": "https://authors.library.caltech.edu/records/x557p-9vd85/files/2009.14071.pdf"
},
"related_objects": [
{
"basename": "stab1502.pdf",
"url": "https://authors.library.caltech.edu/records/x557p-9vd85/files/stab1502.pdf"
}
],
"pub_year": "2021",
"author_list": "Coughlin, Michael W.; Burdge, Kevin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/bawnv-ssm29",
"eprint_id": 109222,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:57:35",
"lastmod": "2026-03-30 06:29:26",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Liu-Honghui",
"name": {
"family": "Liu",
"given": "Honghui"
},
"orcid": "0000-0003-2845-1009"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Lansbury-George-B",
"name": {
"family": "Lansbury",
"given": "George B."
},
"orcid": "0000-0002-5328-9827"
}
]
},
"title": "A highly accreting low-mass black hole hidden in the dust: Suzaku and NuSTAR observations of the NLS1 Mrk 1239",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: nuclei \u2013 galaxies: Seyfert \u2013X-ray: galaxies",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2021 May 4. Received 2021 April 26; in original form 2020 July 28. Published: 10 May 2021. \n\nThis paper was written during the worldwide COVID-19 pandemic in 2020\u20132021. We acknowledge the hard work of all the health care workers around the world. We could not have finished this paper without their protection. JJ acknowledges support from the Tsinghua Shui'Mu Scholar Program and the Tsinghua Astrophysics Outstanding Fellowship. MB acknowledges support from the YCAA Prize Postdoctoral Fellowship. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA, and data obtained from the Suzaku satellite, a collaborative mission between the space agencies of Japan (JAXA) and the USA (NASA). This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center and the California Institute of Technology. \n\nData Availability: All the data can be downloaded from the HEASARC website at https://heasarc.gsfc.nasa.gov.\n\nPublished - stab1306.pdf
Accepted Version - 2105.02078.pdf
",
"abstract": "We present torus modelling for the X-ray spectra of a nearby narrow-line Seyfert 1 galaxy Mrk 1239 (z = 0.0199), based on archival Suzaku, NuSTAR, and Swift observations. Our model suggests very soft intrinsic power-law continuum emission of \u0393 \u2248 2.57 in 2019 and \u0393 \u2248 2.98 in 2007. By applying a correction factor to the unabsorbed X-ray luminosity, we find that Mrk 1239 is accreting near or around the Eddington limit. Our best-fitting spectral model also suggests a torus with a column density of log\u2009(N_(H,ave)/\u2009cm\u207b\u00b2) = 25.0 \u00b1 0.2 and a high covering factor of 0.90 in Mrk 1239, indicating that this source is most likely to be viewed almost face-on with i \u2248 26\u00b0. Our line of sight might cross the edge of the torus with N_(H,los) = 2\u20135 \u00d7 10\u00b2\u00b3\u2009cm\u207b\u00b2. The high Eddington ratio and the high line-of-sight column density makes Mrk 1239 one of the active galactic nuclei that are close to the limit where wind may form near the edge of the torus due to high radiation pressure.",
"date": "2021-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "505",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "702-712",
"id_number": "CaltechAUTHORS:20210520-150005274",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210520-150005274",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Tsinghua Univerisity"
},
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stab1306",
"primary_object": {
"basename": "2105.02078.pdf",
"url": "https://authors.library.caltech.edu/records/bawnv-ssm29/files/2105.02078.pdf"
},
"related_objects": [
{
"basename": "stab1306.pdf",
"url": "https://authors.library.caltech.edu/records/bawnv-ssm29/files/stab1306.pdf"
}
],
"pub_year": "2021",
"author_list": "Jiang, Jiachen; Balokovi\u0107, Mislav; et al."
},
{
"id": "https://authors.library.caltech.edu/records/c7e0t-7gt93",
"eprint_id": 109934,
"eprint_status": "archive",
"datestamp": "2023-08-22 10:24:07",
"lastmod": "2026-03-29 21:34:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Vourlidas-Angelos",
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Roelof-Edmond-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Allen-Robert-C",
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Matthaeus-William-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "Niehof-J-T",
"name": {
"family": "Niehof",
"given": "J. T."
}
},
{
"id": "de-Wet-W",
"name": {
"family": "de Wet",
"given": "W."
}
},
{
"id": "Winslow-R-M",
"name": {
"family": "Winslow",
"given": "R. M."
}
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Kasper-Justin-C",
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
}
]
},
"title": "Energetic particle evolution during coronal mass ejection passage from 0.3 to 1 AU",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "acceleration of particles; solar wind; magnetic fields",
"note": "\u00a9 ESO 2021. Article published by EDP Sciences. \n\nReceived 17 November 2020; Accepted 12 May 2021; Published online 01 July 2021. \n\nParker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). The IS\u2299IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). Simulation results have been provided by the Community Coordinated Modeling Center at Goddard Space Flight Center through their public Runs on Request system (http://ccmc.gsfc.nasa.gov). The ENLIL Model was developed by D. Odstrcil at the University of Colorado at Boulder. We thank the STEREO team for making the SEPT and MAG data used in this study publicly available. The SOHO/LASCO data used here are produced by a consortium of the Naval Research Laboratory (USA), Max-Planck-Institut fuer Aeronomie (Germany), Laboratoire d'Astronomie (France), and the University of Birmingham (UK). SOHO is a project of international cooperation between ESA and NASA. R.M.W. acknowledges support from NASA grant 80NSSC19K0914.\n\nPublished - aa39933-20.pdf
",
"abstract": "We provide analysis of a coronal mass ejection (CME) that passed over Parker Solar Probe (PSP) on January 20, 2020 when the spacecraft was at just 0.32 AU. The Integrated Science Investigation of the Sun instrument suite measures energetic particle populations associated with the CME before, during, and after its passage over the spacecraft. We observe a complex evolution of energetic particles, including a brief ~2 h period where the energetic particle fluxes are enhanced and the nominal orientation of the energetic particle streaming outward from the Sun (from 30 to 100 keV nuc\u207b\u00b9) abruptly reverses inward toward the Sun. This transient and punctuated evolution highlights the importance of magnetic field structures that connect the spacecraft to different acceleration sites, one of which is likely more distant from the Sun than PSP during the evolution of the CME. We discuss these characteristics and what they tell us about the source of the energetic particles. During this period, PSP was radially aligned with the Solar Terrestrial Relations Observatory A (STEREO-A), which measured the same CME when it passed 1 AU. The magnetic field measurements at both spacecraft are remarkably similar, indicating that the spacecraft are likely encountering the same portion of the magnetic structure that has not evolved significantly in transit. The energetic particle observations on the other hand, are quite different at STEREO-A, showing how transport effects have acted on the energetic particle populations and obscured the detailed properties present earlier in the development of the CME. This event provides a unique case study in how energetic particle populations evolve as CMEs propagate through the heliosphere.",
"date": "2021-07",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "651",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A2",
"id_number": "CaltechAUTHORS:20210720-194559203",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210720-194559203",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K0914"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202039933",
"primary_object": {
"basename": "aa39933-20.pdf",
"url": "https://authors.library.caltech.edu/records/c7e0t-7gt93/files/aa39933-20.pdf"
},
"pub_year": "2021",
"author_list": "Joyce, C. J.; McComas, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/f2ne7-rtz87",
"eprint_id": 109230,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:57:52",
"lastmod": "2026-03-30 06:27:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Kretschmar-Peter",
"name": {
"family": "Kretschmar",
"given": "P."
},
"orcid": "0000-0001-9840-2048"
},
{
"id": "Pottschmidt-Katja",
"name": {
"family": "Pottschmidt",
"given": "K."
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "Ptak-Andrew",
"name": {
"family": "Ptak",
"given": "A."
},
"orcid": "0000-0001-5655-1440"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "N."
}
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "Long-term pulse period evolution of the ultra-luminous X-ray pulsar NGC 7793 P13",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 X-rays: binaries \u2013 stars: neutron \u2013 pulsars: individual: NGC7793 P13",
"note": "\u00a9 ESO 2021. Article published by EDP Sciences. \n\nReceived 22 February 2021; Accepted 28 April 2021; Published online 16 July 2021. \n\nWe would like the thank the referee for the very useful comments that helped to improve the manuscript. DJW and MJM acknowledge support from STFC Ernest Rutherford fellowships. This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the nustardas software package, jointly developed by the ASDC (Italy) and Caltech (USA). This research has also made use of data obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester, and also made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. This research has made use of a collection of ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/). The material is based upon work supported by NASA under award number 80GSFC17M0002.\n\nPublished - aa40625-21.pdf
Accepted Version - 2105.04229.pdf
",
"abstract": "Ultra-luminous X-ray pulsars (ULXPs) provide a unique opportunity to study persistent super-Eddington accretion. Here we present the results of a long-term monitoring campaign of ULXP NGC 7793 P13, focusing on the pulse period evolution and the determination of the orbital ephemeris. Over our four year monitoring campaign with Swift, XMM-Newton, and NuSTAR, we measured a continuous spin-up with an average value of \u1e56 \u2248 \u22123.8 \u00d7 10\u207b\u00b9\u00b9 s s\u207b\u00b9. We find that the strength of the spin-up is independent of the observed X-ray flux, indicating that despite a drop in observed flux in 2019, accretion onto the source has continued at largely similar rates. The source entered an apparent off-state in early 2020, which might have resulted in a change in the accretion geometry as no pulsations were found in observations in July and August 2020. We used the long-term monitoring to update the orbital ephemeris, as well as the periodicities seen in both the observed optical and UV magnitudes and the X-ray fluxes. We find that the optical and UV period is very stable over the years, with P_(UV) = 63.75_(\u22120.12)^(+0.17) d. The best-fit orbital period determined from our X-ray timing results is 64.86 \u00b1 0.19 d, which is almost a day longer than previously implied, and the X-ray flux period is 65.21 \u00b1 0.15 d, which is slightly shorter than previously measured. The physical origin of these different flux periods is currently unknown. We study the hardness ratio of the XMM-Newton and NuSTAR data between 2013\u22122020 to search for indications of spectral changes. We find that the hardness ratios at high energies are very stable and not directly correlated with the observed flux. At lower energies we observe a small hardening with increased flux, which might indicate increased obscuration through outflows at higher luminosities. Comparing the changes in flux with the observed pulsed fraction, we find that the pulsed fraction is significantly higher at low fluxes. This seems to imply that the accretion geometry already changed before the source entered the deep off-state. We discuss possible scenarios to explain this behavior, which is likely driven by a precessing accretion disk.",
"date": "2021-07",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "651",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A75",
"id_number": "CaltechAUTHORS:20210520-150032176",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210520-150032176",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
},
{
"agency": "NASA",
"grant_number": "80GSFC17M0002"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202140625",
"primary_object": {
"basename": "2105.04229.pdf",
"url": "https://authors.library.caltech.edu/records/f2ne7-rtz87/files/2105.04229.pdf"
},
"related_objects": [
{
"basename": "aa40625-21.pdf",
"url": "https://authors.library.caltech.edu/records/f2ne7-rtz87/files/aa40625-21.pdf"
}
],
"pub_year": "2021",
"author_list": "F\u00fcrst, F.; Walton, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6ydmw-fsk71",
"eprint_id": 109609,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:58:28",
"lastmod": "2026-03-29 21:00:14",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Gatuzz-Efrain",
"name": {
"family": "Gatuzz",
"given": "Efra\u00edn"
},
"orcid": "0000-0002-3252-9633"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Kallman-Timothy-R",
"name": {
"family": "Kallman",
"given": "Timothy R."
},
"orcid": "0000-0002-5779-6906"
}
]
},
"title": "Nitrogen X-ray absorption in the local ISM",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "ISM: abundances, ISM: atoms, ISM: structure, Galaxy: structure, X-rays: ISM",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nAccepted 2021 April 21. Received 2021 April 21; in original form 2020 September 17. \n\nWe thank the anonymous referee for the careful reading of our manuscript and the valuable comments. JAG acknowledges support from the Smithsonian Astrophysical Observatory grant AR0-21003X, and from the Alexander von Humboldt Foundation. \n\nDATA AVAILABILITY. Observations analysed in this article are available in the XMM\u2013Newton Science Archive (XSA) (http://nxsa.esac.esa.int/nxsa-web/#search). The ISMabs model is included in the XSPEC data analysis software (https://heasarc.gsfc.nasa.gov/xanadu/xspec/).\n\nPublished - stab1185.pdf
Accepted Version - 2104.11256.pdf
",
"abstract": "Nitrogen is one of the most abundant metals in the interstellar medium (ISM), and thus it constitutes an excellent test to study a variety of astrophysical environments, ranging from nova to active galactic nuclei. We present a detailed analysis of the gaseous component of the N K-edge using high-resolution XMM\u2013Newton spectra of 12 Galactic and 40 extragalactic sources. For each source, we have estimated column densities for N I, N II, N III, N V, N VI, and N VII ionic species, which trace the cold, warm, and hot phases of the local Galactic ISM. We have found that the cold-warm component column densities decrease with the Galactic latitude, while the hot component does not. Moreover, the cold column density distribution is in good agreement with UV measurements. This is the first detailed analysis of the nitrogen K-edge absorption due to ISM using high-resolution X-ray spectra.",
"date": "2021-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "504",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "4460-4471",
"id_number": "CaltechAUTHORS:20210626-222733320",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210626-222733320",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Smithsonian Astrophysical Observatory",
"grant_number": "AR0-21003X"
},
{
"agency": "Alexander von Humboldt Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stab1185",
"primary_object": {
"basename": "2104.11256.pdf",
"url": "https://authors.library.caltech.edu/records/6ydmw-fsk71/files/2104.11256.pdf"
},
"related_objects": [
{
"basename": "stab1185.pdf",
"url": "https://authors.library.caltech.edu/records/6ydmw-fsk71/files/stab1185.pdf"
}
],
"pub_year": "2021",
"author_list": "Gatuzz, Efra\u00edn; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9e48j-y8x63",
"eprint_id": 109983,
"eprint_status": "archive",
"datestamp": "2023-08-20 04:00:10",
"lastmod": "2026-03-30 08:58:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Buchner-Johannes",
"name": {
"family": "Buchner",
"given": "Johannes"
},
"orcid": "0000-0003-0426-6634"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Wada-Keiichi",
"name": {
"family": "Wada",
"given": "Keiichi"
}
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Nandra-Kirpal",
"name": {
"family": "Nandra",
"given": "Kirpal"
},
"orcid": "0000-0002-7150-9192"
}
]
},
"title": "Physically motivated X-ray obscurer models",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 accretion, accretion disks \u2013 methods: numerical \u2013 X-rays: general \u2013 radiative transfer \u2013 scattering",
"note": "\u00a9 J. Buchner et al. 2021. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0),\nwhich permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nOpen Access funding provided by Max Planck Society. \n\nReceived: 20 December 2018; Accepted: 1 June 2021. \n\nWe thank the anonymous referees for constructive suggestions which improved the manuscript. We acknowledge support from the CONICYT-Chile grants Basal-CATA PFB-06/2007 (JB, FEB), ANID grants CATA-Basal AFB-170002 (JB, FEB), FONDECYT Regular 1141218, 1190818 and 1200495 (all FEB), FONDECYT Postdoctorados 3160439 (JB), \"EMBIGGEN\" Anillo ACT1101 (FEB), and the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS (JB, FEB). This research was supported by the DFG cluster of excellence \"Origin and Structure of the Universe\". MiB acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program, the YCAA Prize Postdoctoral Fellowship, grant NNX14AQ07H, and support from the Black Hole Initiative at Harvard University, which is funded in part by the Gordon and Betty Moore Foundation (grant GBMF8273) and in part by the John Templeton Foundation. KW was supported by JSPS KAKENHI Grant Number 16H03959. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of SIMBAD (Wenger et al. 2000) and its excellent query API, operated by the Strasbourg astronomical Data Center (CDS).\n\nPublished - aa34963-18.pdf
Accepted Version - 2106.08331.pdf
",
"abstract": "Context. The nuclear obscurer of active galactic nuclei (AGN) is poorly understood in terms of its origin, geometry, and dynamics. \n\nAims. We investigate whether physically motivated geometries emerging from hydro-radiative simulations can be differentiated with X-ray reflection spectroscopy. \n\nMethods. For two new geometries, the radiative fountain model and a warped disk, we release spectral models produced with the ray tracing code XARS. We contrast these models with spectra of three nearby AGN taken by NuSTAR and Swift/BAT. \n\nResults. Along heavily obscured sightlines, the models present different 4\u221220 keV continuum spectra. These can be differentiated by current observations. Spectral fits of the Circinus Galaxy favour the warped disk model over the radiative fountain, and clumpy or smooth torus models.\nConclusions. The necessary reflector (N_H\u2004\u2265\u200410\u00b2\u2075 cm\u00b2) suggests a hidden population of heavily Compton-thick AGN amongst local galaxies. X-ray reflection spectroscopy is a promising pathway to understand the nuclear obscurer in AGN.",
"date": "2021-07",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "651",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A58",
"id_number": "CaltechAUTHORS:20210722-211238306",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210722-211238306",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "BASAL-CATA",
"grant_number": "PFB-06/2007"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1141218"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3160439"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ACT1101"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
},
{
"agency": "Gordon and Betty Moore Foundation",
"grant_number": "GBMF8273"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "16H03959"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/201834963",
"primary_object": {
"basename": "2106.08331.pdf",
"url": "https://authors.library.caltech.edu/records/9e48j-y8x63/files/2106.08331.pdf"
},
"related_objects": [
{
"basename": "aa34963-18.pdf",
"url": "https://authors.library.caltech.edu/records/9e48j-y8x63/files/aa34963-18.pdf"
}
],
"pub_year": "2021",
"author_list": "Buchner, Johannes; Brightman, Murray; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nvr6t-qq802",
"eprint_id": 109450,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:29:20",
"lastmod": "2026-03-29 13:53:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Aly",
"given": "A."
}
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Niehof",
"given": "J. T."
}
},
{
"name": {
"family": "M\u00f6bius",
"given": "E."
}
},
{
"name": {
"family": "Lee",
"given": "M."
}
},
{
"name": {
"family": "Bower",
"given": "J."
}
},
{
"name": {
"family": "Bale",
"given": "S."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Case",
"given": "A."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"name": {
"family": "de Wet",
"given": "W."
}
},
{
"name": {
"family": "Goetz",
"given": "K."
},
"orcid": "0000-0003-0420-3633"
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Allen",
"given": "R."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Korreck",
"given": "K."
},
"orcid": "0000-0001-6095-2490"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Malandraki",
"given": "O."
},
"orcid": "0000-0002-4751-6835"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "A new view of energetic particles from stream interaction regions observed by Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: magnetic fields \u2013 solar wind \u2013 Sun: heliosphere \u2013 shock waves \u2013 acceleration of particles",
"note": "\u00a9 ESO 2021. Article published by EDP Sciences. \n\nReceived 7 September 2020; Accepted 14 November 2020. Published online 02 June 2021. \n\nWe are deeply indebted to everyone that helped make the Parker Solar Probe (PSP) mission possible. We thank all of the outstanding scientists, engineers, technicians, and administrative support people across all of the IS\u2299IS, FIELDS and SWEAP institutions that produced and supported the IS\u2299IS, FIELDS and SWEAP instrument suites, support its operations and the scientific analysis of its data. This work was supported as part of the PSP mission under contract NNN06AA01C. NAS and CMSC were also supported under LWS grant \"New Insights into SEP Sources, Acceleration, and Propagation: an Integrated Observation-Modeling Approach\", grant number 80NSSC19K0067. The IS\u2299IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission.\n\nPublished - aa39352-20.pdf
",
"abstract": "Early observations from the first orbit of Parker Solar Probe (PSP) show recurrent stream interaction regions that form close to the Sun. Energetic particle enhancements were observed on the 320th\u2013326th day of the year 2018, which corresponds to ~1\u20137 days after the passage of the stream interface between faster and slower solar wind. Energetic particles stream into the inner heliosphere to the PSP spacecraft near 0.33 au (71 solar radii) where they are measured by the Integrated Science Investigation of the Sun (IS\u2299IS). The large 6-day time interval over which energetic particles are observed after the stream passage provides a unique perspective on the development of stream interactions within the heliosphere. The long duration of energetic particle enhancements suggests that particles stream in through the inner heliosphere more directly along magnetic field lines that form a sub-Parker spiral structure due to magnetic footpoint motion at the Sun and shearing of the magnetic field in the rarefaction region behind the stream interface. The strong build-up of energetic particle fluxes in the first 3 days after the passage of the stream interface indicates that suprathermal populations are enhanced near the interaction region through compression or other acceleration processes in addition to being diffusively accelerated. The early increases in energetic particle fluxes (in the first 3 days) in the formation of these events allows for the characterization of the acceleration associated with these suprathermal seed populations. Thus, we show that the time history of energetic particle fluxes observed by IS\u2299IS provides a new view of particle acceleration at stream interaction regions throughout the inner heliosphere.",
"date": "2021-06",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "650",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A24",
"id_number": "CaltechAUTHORS:20210609-073141024",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210609-073141024",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0067"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202039352",
"primary_object": {
"basename": "aa39352-20.pdf",
"url": "https://authors.library.caltech.edu/records/nvr6t-qq802/files/aa39352-20.pdf"
},
"pub_year": "2021",
"author_list": "Schwadron, N. A.; Joyce, C. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/hbkr7-40y56",
"eprint_id": 109447,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:28:48",
"lastmod": "2026-03-29 13:54:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
}
]
},
"title": "Parker Solar Probe observations of He/H abundance variations in SEP events inside 0.5 au",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: particle emission \u2013 Sun: activity \u2013 solar-terrestrial relations",
"note": "\u00a9 ESO 2021. Article published by EDP Sciences. \n\nReceived 30 August 2020; Accepted 1 December 2020. Published online 02 June 2021. \n\nThis work was supported by NASA's Parker Solar Probe Mission, contract NNN06AA01C. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We thank all the scientists and engineers who have worked hard to make PSP a successful mission. In particular, we thank B. Kecman, W. R. Cook and J. Burnham, without whom the EPI-Hi instrument would not be possible. S.D.B. acknowledges support of the Leverhulme Trust Visiting Professorship program. A.V. acknowledges support from NASA grants 80NSSC19K1261 and 80NSSC19K0069. The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) was produced by an international consortium of the Naval Research Laboratory (USA), Lockheed Martin Solar and Astrophysics Lab (USA), NASA Goddard Space Flight Center (USA), Rutherford Appleton Laboratory (UK), University of Birmingham (UK), Max Planck Institute for Solar System Research (Germany), Centre Spatiale de Li\u00e8ge (Belgium), Institut d'Optique Theorique et Appliqu\u00e9e (France), and Institut d'Astrophysique Spatiale (France). STEREO data are available for download at https://secchi.nrl.navy.mil/. This paper uses data from the CACTus CME catalog, generated and maintained by the SIDC at the Royal Observatory of Belgium. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - aa39299-20.pdf
",
"abstract": "Aims. The Parker Solar Probe (PSP) orbit provides an opportunity to study the inner heliosphere at distances closer to the Sun than previously possible. Due to the solar minimum conditions, the initial orbits of PSP yielded only a few solar energetic particle (SEP) events for study. Recently during the fifth orbit, at distances from 0.45 to 0.3 au, the energetic particle suite on PSP, Integrated Science Investigation of the Sun (IS\u2299IS), observed a series of six SEP events, adding to the limited number of SEP events studied inside of 0.5 au. Variations in the H and He spectra and the He/H abundance ratio are examined and discussed in relation to the identified solar source regions and activity.\nMethods. IS\u2299IS measures the energetic particle environment from ~20 keV to >100 MeV/nuc. Six events were selected using the ~1 MeV proton intensities, and while small, they were sufficient to calculate proton and helium spectra from ~1 to ~10 MeV/nuc. For the three larger events, the He/H ratio as a function of energy was determined. Using the timing of the associated radio bursts, solar sources were identified for each event and the eruptions were examined in extreme ultraviolet emission.\nResults. The largest of the selected events has peak ~1 MeV proton intensities of 3.75 (cm\u00b2 sr s MeV)\u207b\u00b9. Within uncertainties, the He and H spectra have similar power law forms with indices ranging from \u22122.3 to \u22123.3. For the three largest events, the He/H ratios are found to be relatively energy independent; however, the ratios differ substantially with values of 0.0033 \u00b1 0.0013, 0.177 \u00b1 0.047, and 0.016 \u00b1 0.009. An additional compositional variation is evident in both the \u00b3He and electron signatures. These variations are particularly interesting as the three larger events are likely a result of similar eruptions from the same active region.",
"date": "2021-06",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "650",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A23",
"id_number": "CaltechAUTHORS:20210608-133059480",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210608-133059480",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1261"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0069"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202039299",
"primary_object": {
"basename": "aa39299-20.pdf",
"url": "https://authors.library.caltech.edu/records/hbkr7-40y56/files/aa39299-20.pdf"
},
"pub_year": "2021",
"author_list": "Cohen, C. M. S.; Christian, E. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/fhxw7-c2s45",
"eprint_id": 109439,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:28:43",
"lastmod": "2026-03-29 14:24:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Burnham-J-A",
"name": {
"family": "Burnham",
"given": "J. A."
}
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cook-Walter-R",
"name": {
"family": "Cook",
"given": "W. R."
}
},
{
"id": "Crabill-Robert-M",
"name": {
"family": "Crabill",
"given": "R. M."
}
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"id": "Kecman-Branislav",
"name": {
"family": "Kecman",
"given": "B."
}
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Rusert-M-D",
"name": {
"family": "Rusert",
"given": "M. D."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Goodwin",
"given": "P. A."
}
},
{
"name": {
"family": "Link",
"given": "J. T."
}
},
{
"name": {
"family": "Nahory",
"given": "B. W."
}
},
{
"name": {
"family": "Shuman",
"given": "S. A."
}
},
{
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
},
{
"name": {
"family": "Tindall",
"given": "C. S."
}
},
{
"name": {
"family": "Black",
"given": "H."
}
},
{
"name": {
"family": "Bullough",
"given": "M."
}
},
{
"name": {
"family": "Clarke",
"given": "N."
}
},
{
"name": {
"family": "Glasson",
"given": "V."
}
},
{
"name": {
"family": "Greenwood",
"given": "N."
}
},
{
"name": {
"family": "Hawkins",
"given": "C."
}
},
{
"name": {
"family": "Johnson",
"given": "T. L."
}
},
{
"name": {
"family": "Newton",
"given": "A."
}
},
{
"name": {
"family": "Richardson",
"given": "K."
}
},
{
"name": {
"family": "Walsh",
"given": "S."
}
},
{
"name": {
"family": "Wilburn",
"given": "C."
}
},
{
"name": {
"family": "Birdwell",
"given": "B."
}
},
{
"name": {
"family": "Everett",
"given": "D. T."
}
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Weidner",
"given": "S. E."
}
},
{
"name": {
"family": "Angold",
"given": "N. G."
}
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
}
]
},
"title": "Thin silicon solid-state detectors for energetic particle measurements. Development, characterization, and application on NASA's Parker Solar Probe mission",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "instrumentation: detectors \u2013 Sun: particle emission \u2013 acceleration of particles \u2013 space vehicles: instruments",
"note": "\u00a9 ESO 2021. Article published by EDP Sciences. \n\nReceived 24 October 2020; Accepted 3 December 2020. Published online 02 June 2021. \n\nWe thank W. C. Tang for suggesting the use of SOI wafers as the basis for thin detector fabrication, B. Eyre for research on optimizing etching processes, J. Klemic (deceased) for developing the etching process used for thinning the detectors processed at LBNL, and B. D. Milliken for pioneering the technique used for thickness mapping. We thank S. Holland for useful discussions and S. M. Krimigis provided helpful comments about the thin silicon detectors used on Voyager. Important contributions to the success of the IS\u2299IS EPI-Hiinstrument were made by numerous other scientists, engineers, and technicians. Particular thanks are due to G. Dirks, D. H. Do, J. J. Hanley, L. Hernandez, T. L. Johnson, S. Lopez, H. Miyasaka, G. Riggins, B. Rodriguez, K. Simms, and M. L. White. We gratefully acknowledge the test support provided by Michigan State University's National Superconducting Cyclotron Laboratory, Texas A&M University's Cyclotron Institute, and the Lawrence Berkeley National Laboratory's 88-inch Cyclotron Laboratory. This work was supported, in part, by NASA's Parker Solar Probe Mission, contract NNN06AA01C. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. Earlier detector development work at JPL, Caltech, and LBNL was supported by several NASA grants. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - aa39754-20.pdf
",
"abstract": "Context. Silicon solid-state detectors are commonly used for measuring the specific ionization, dE\u2215dx, in instruments designed for identifying energetic nuclei using the dE\u2215dx versus total energy technique in space and in the laboratory. The energy threshold and species resolution of the technique strongly depend on the thickness and thickness uniformity of these detectors.\nAims. Research has been carried out to develop processes for fabricating detectors that are thinner than 15 \u03bcm, that have a thickness uniformity better than 0.2 \u03bcm over cm\u00b2 areas, and that are rugged enough to survive the acoustic and vibration environments of a spacecraft launch.\nMethods. Silicon-on-insulator wafers that have a device layer of the desired detector thickness supported by a thick handle layer were used as starting material. Standard processing techniques were used to fabricate detectors on the device layer, and the underlying handle-layer material was etched away leaving a thin, uniform detector surrounded by a thick, supporting frame.\nResults. Detectors as thin as 12 \u03bcm were fabricated in two laboratories and successfully subjected to environmental and performance tests. Two detector designs were used in the High-energy Energetic Particles Instrument, which is part of the Integrated Science Investigation of the Sun instrument suite on NASA's Parker Solar Probe spacecraft. These detectors have been performing well for more than two years in space.\nConclusions. Thin silicon detectors in d E\u2215dx versus total energy instruments enable the identification of nuclei with energies down to ~1 MeV nuc\u207b\u00b9. This research suggests that detectors at least a factor of two thinner should be achievable using this fabrication technique.",
"date": "2021-06",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "650",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A27",
"id_number": "CaltechAUTHORS:20210608-101914332",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210608-101914332",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202039754",
"primary_object": {
"basename": "aa39754-20.pdf",
"url": "https://authors.library.caltech.edu/records/fhxw7-c2s45/files/aa39754-20.pdf"
},
"pub_year": "2021",
"author_list": "Wiedenbeck, M. E.; Burnham, J. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vr5gp-mw017",
"eprint_id": 109438,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:28:17",
"lastmod": "2026-03-28 23:52:22",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "McNutt-Ralph-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Roelof-Edmond-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Allen-Robert-C",
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"id": "Szalay-Jamey-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Desai-Mihir-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Giacalone-Joe",
"name": {
"family": "Giacalone",
"given": "J."
},
"orcid": "0000-0002-0850-4233"
},
{
"id": "Matthaeus-William-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "Bale-Stuart-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Kasper-Justin-C",
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
}
]
},
"title": "Time evolution of stream interaction region energetic particle spectra in the inner heliosphere",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "acceleration of particles \u2013 solar wind \u2013 magnetic fields",
"note": "\u00a9 ESO 2021. Article published by EDP Sciences. \n\nReceived 2 September 2020; Accepted 30 March 2021. Published online 02 June 2021. \n\nThis work was supported as a part of the Integrated Science Investigations of the Sun on NASA's Parker Solar Probe mission, under contract NNN06AA01C. The IS\u2299IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - aa39330-20.pdf
",
"abstract": "We analyze an energetic proton event associated with a stream interaction region (SIR) that was observed at Parker Solar Probe on day 320 of 2018 when the spacecraft was just 0.34 AU from the Sun. Using the Integrated Science Investigation of the Sun instrument suite, we perform a spectral analysis of the event and show how the observed spectra evolve over the course of the event. We find that the spectra from the first day of the event are much more consistent with local acceleration at a weak compression, while spectra from later on are more typical of SIR-related events in which particles accelerated at distant shocks dominate. After the first day, the spectra remain approximately constant, which indicates that the modulation of energetic particles during transit from the presumed source region is weaker than previously thought. We argue that these observations can be explained by a sub-Parker spiral magnetic field structure connecting the spacecraft to a source region in the SIR that is relatively close to the Sun. We further propose that acceleration at weak, pre-shock compressions likely plays an important role in observations of SIR-related events in the inner heliosphere and that future modelling of such events should consider acceleration all along the compression region, not just at the distant shock region.",
"date": "2021-06",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "650",
"publisher": "EDP Sciences",
"pagerange": "Art. No. L5",
"id_number": "CaltechAUTHORS:20210608-095304738",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210608-095304738",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/202039330",
"primary_object": {
"basename": "aa39330-20.pdf",
"url": "https://authors.library.caltech.edu/records/vr5gp-mw017/files/aa39330-20.pdf"
},
"pub_year": "2021",
"author_list": "Joyce, C. J.; McComas, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/hgbcm-bsv10",
"eprint_id": 109193,
"eprint_status": "archive",
"datestamp": "2023-08-20 03:18:23",
"lastmod": "2026-03-30 06:23:22",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yerong",
"name": {
"family": "Xu",
"given": "Yerong"
},
"orcid": "0000-0002-2523-5485"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "The Nature of Soft Excess in ESO 362-G18 Revealed by XMM-Newton and NuSTAR Spectroscopy",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 August 10; revised 2021 March 24; accepted 2021 March 30; published 2021 May 19. \n\nWe thank the referee for their constructive comments. J.A.G. acknowledges support from NASA grant NNX17AJ65G and from the Alexander von Humboldt Foundation. He is also a member of Teams 458 and 486 at the International Space Science Institute (ISSI), Bern, Switzerland, and acknowledges support from ISSI during the meetings in Bern. R.M.T.C. has been supported by NASA grant 80NSSC177K0515. D.J.W. acknowledges support from STFC through an Ernest Rutherford fellowship. This work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. We thank the NuSTAR operations, software, and calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacilities: NuSTAR (Harrison et al. 2013), XMM-Newton (Jansen et al. 2001), Athena (Nandra et al. 2013), eXTP (Zhang et al. 2017), HEX-P (Madsen et al. 2018). \n\nSoftware: xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), relxillD/relxilllpD (Dauser et al. 2014; Garc\u00eda et al. 2014, 2016), borus12 (Balokovi\u0107 et al. 2019).\n\nPublished - Xu_2021_ApJ_913_13.pdf
Accepted Version - 2103.17002.pdf
",
"abstract": "We present a detailed spectral analysis of the joint XMM-Newton and NuSTAR observations of the active galactic nuclei (AGNs) in the Seyfert 1.5 Galaxy ESO 362-G18. The broadband (0.3\u201379 keV) spectrum shows the presence of a power-law continuum with a soft excess below 2 keV, iron K\u03b1 emission (~6.4 keV), and a Compton hump (peaking at ~20 keV). We find that the soft excess can be modeled by two different possible scenarios: a warm (kT_e ~ 0.2 keV) and optically thick (\u03c4 ~ 34) Comptonizing corona, or with a relativistically blurred reflection off a high-density (log [n_e/cm\u207b\u00b3 > 18.3) inner disk. These two models cannot be easily distinguished solely from their fit statistics. However, the low temperature (kT_e ~ 20 keV) and the thick optical depth (\u03c4 ~ 5) of the hot corona required by the warm corona scenario are uncommon for AGNs. We also fit a \"hybrid\" model, which includes both disk reflection and a warm corona. Unsurprisingly, as this is the most complex of the models considered, this provides the best fit, and more reasonable coronal parameters. In this case, the majority of the soft excess flux arises in the warm corona component. However, based on recent simulations of warm coronae, it is not clear whether such a structure can really exist at the low accretion rates relevant for ESO 362-G18 (\u1e41 ~ 0.015). This may therefore argue in favor of a scenario in which the soft excess is instead dominated by the relativistic reflection. Based on this model, we find that the data would require a compact hot corona (h ~ 3 R_(Horizon)) around a rapidly spinning (a_\u2605 > 0.927) black hole.",
"date": "2021-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "913",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 13",
"id_number": "CaltechAUTHORS:20210519-141321220",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210519-141321220",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX17AJ65G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "International Space Science Institute (ISSI)"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/abf430",
"primary_object": {
"basename": "2103.17002.pdf",
"url": "https://authors.library.caltech.edu/records/hgbcm-bsv10/files/2103.17002.pdf"
},
"related_objects": [
{
"basename": "Xu_2021_ApJ_913_13.pdf",
"url": "https://authors.library.caltech.edu/records/hgbcm-bsv10/files/Xu_2021_ApJ_913_13.pdf"
}
],
"pub_year": "2021",
"author_list": "Xu, Yerong; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jk1vs-38173",
"eprint_id": 109167,
"eprint_status": "archive",
"datestamp": "2023-08-22 09:49:58",
"lastmod": "2026-03-28 23:02:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rankin-Jamie-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Christian-Eric-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Joyce-Colin-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Posner-Arik",
"name": {
"family": "Posner",
"given": "A."
}
},
{
"id": "Schwadron-Nathan-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Strauss-Roelf-D",
"name": {
"family": "Strauss",
"given": "R. D."
},
"orcid": "0000-0002-0205-0808"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "First Observations of Anomalous Cosmic Rays in to 36 Solar Radii",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Cosmic rays; Solar wind; Heliosphere; Solar energetic particles; Solar physics; Solar cycle; Quiet sun; Particle astrophysics; Interplanetary magnetic fields; Plasma astrophysics; Interplanetary particle acceleration; Pickup ions",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2021 February 2; revised 2021 March 2; accepted 2021 March 3; published 2021 May 13. \n\nThis work was supported as a part of the Integrated Science Investigation of the Sun on NASA's Parker Solar Probe mission, under contract NNN06AA01C. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). We thank the SOHO/EPHIN team at Christian-Albrechts-Universit\u00e4t zu Kiel for making their data publicly available and Patrick K\u00fchl and Bernd Heber for their guidance as well as their thorough documentation of the level 3 data product. We also gratefully acknowledge the support provided by Michigan State University's National Superconducting Cyclotron Laboratory, Texas A&M University's Cyclotron Institute, and the Lawrence Berkeley National Laboratory's 88 inch Cyclotron Laboratory during EPI-Hi's calibration and testing. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program. Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We thank all the scientists and engineers who have worked hard to make PSP a successful mission.\n\nPublished - Rankin_2021_ApJ_912_139.pdf
",
"abstract": "NASA's Parker Solar Probe mission continues to travel closer to the Sun than any prior human-made object, with an expected closest approach of <10 solar radii (<0.046 au) by 2024. On board, the Integrated Science Investigation of the Sun instrument suite makes unprecedented in situ measurements of energetic particles in the near-Sun environment. The current low level of solar activity offers a prime opportunity to measure cosmic rays closer to the Sun than ever before. We present the first observations of anomalous cosmic rays in to 36 solar radii (0.166 au), focusing specifically on helium. Our results indicate a strong radial intensity gradient of ~25 \u00b1 5%/au over energies of ~4 to ~45 MeV/nuc. These values are larger than prior observations, further out in the heliosphere, and come at a unique time in our understanding and modeling of particle transport and acceleration, particularly as both Voyagers have crossed the heliopause and IBEX has accumulated a full solar cycle of observations. Thus, continued measurements of cosmic rays by Parker Solar Probe will play a critical role in linking past observations with our present knowledge and significantly advancing our understanding of cosmic ray transport in the heliosphere.",
"date": "2021-05-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "912",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 139",
"id_number": "CaltechAUTHORS:20210518-084408052",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210518-084408052",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abec7e",
"primary_object": {
"basename": "Rankin_2021_ApJ_912_139.pdf",
"url": "https://authors.library.caltech.edu/records/jk1vs-38173/files/Rankin_2021_ApJ_912_139.pdf"
},
"pub_year": "2021",
"author_list": "Rankin, J. S.; McComas, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/a0pfa-9y081",
"eprint_id": 108894,
"eprint_status": "archive",
"datestamp": "2023-08-22 09:37:48",
"lastmod": "2026-03-29 15:24:04",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "A. D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Degenaar-N",
"name": {
"family": "Degenaar",
"given": "N."
}
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "J. A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Cackett-Edward-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
}
},
{
"id": "Shaw-Aarran-W",
"name": {
"family": "Shaw",
"given": "A. W."
},
"orcid": "0000-0002-8808-520X"
},
{
"id": "Chakrabarty-Deepto",
"name": {
"family": "Chakrabarty",
"given": "D."
},
"orcid": "0000-0001-8804-8946"
}
]
},
"title": "Simultaneous NICER and NuSTAR Observations of the Ultracompact X-Ray Binary 4U 1543\u2013624",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Low-mass x-ray binary stars",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 December 7; revised 2021 March 8; accepted 2021 March 9; published 2021 April 26. \n\nSupport for this work was provided by NASA through the NASA Hubble Fellowship grant #HST-HF2-51440.001 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Additional support was provided from NASA under the NICER Guest Observer grant 80NSSC21K0121. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (Caltech, USA). J.A.G. acknowledges support from NASA grant 80NSSC20K1238 and from the Alexander von Humboldt Foundation. E.M.C. gratefully acknowledges support through NSF CAREER award number AST-1351222. J.A.T. acknowledges partial support from NASA under NICER Guest Observer grant 80NSSC19K1445. D.J.K.B. acknowledges funding from the Royal Society. \n\nFacilities: ADS - , HEASARC - , NICER - , NuSTAR. - \n\nSoftware: HEAsoft (v6.27.2, HEASARC 2014), nustardas (v1.9.2), nicerdas (2020-04-23_V007a), xspec (v12.11.0, Arnaud 1996), Stingray (Huppenkothen et al. 2019).\n\nPublished - Ludlam_2021_ApJ_911_123.pdf
",
"abstract": "We present the first joint NuSTAR and NICER observations of the ultracompact X-ray binary (UCXB) 4U 1543\u2212624 obtained in 2020 April. The source was at a luminosity of L_(0.5\u221250 keV) = 4.9(D/7 kpc)\u00b2 \u00d7 1036 erg s\u207b\u00b9 and showed evidence of reflected emission in the form of an O viii line, Fe K line, and Compton hump within the spectrum. We used a full reflection model, known as xillverCO, that is tailored for the atypical abundances found in UCXBs, to account for the reflected emission. We tested the emission radii of the O and Fe line components and conclude that they originate from a common disk radius in the innermost region of the accretion disk (R_(in) \u2264 1.07 R_(ISCO)). Assuming that the compact accretor is a neutron star (NS) and the position of the inner disk is the Alfv\u00e9n radius, we placed an upper limit on the magnetic field strength to be B \u2264 0.7(D/7 kpc) \u00d7 10\u2078 G at the poles. Given the lack of pulsations detected and position of R_(in), it was likely that a boundary layer region had formed between the NS surface and inner edge of the accretion disk with an extent of 1.2 km. This implies a maximum radius of the neutron star accretor of R_(NS) \u2264 12.1 km when assuming a canonical NS mass of 1.4 M_\u2299.",
"date": "2021-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "911",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 123",
"id_number": "CaltechAUTHORS:20210429-144554967",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210429-144554967",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "NASA",
"grant_number": "80NSSC21K0121"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1238"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NSF",
"grant_number": "AST-1351222"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1445"
},
{
"agency": "Royal Society"
},
{
"agency": "NASA Einstein Fellowship"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/abedb0",
"primary_object": {
"basename": "Ludlam_2021_ApJ_911_123.pdf",
"url": "https://authors.library.caltech.edu/records/a0pfa-9y081/files/Ludlam_2021_ApJ_911_123.pdf"
},
"pub_year": "2021",
"author_list": "Ludlam, R. M.; Jaodand, A. D.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/g09sn-sfx55",
"eprint_id": 117076,
"eprint_status": "archive",
"datestamp": "2023-08-20 02:43:03",
"lastmod": "2026-03-28 22:25:35",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "Christina M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Li-Gang",
"name": {
"family": "Li",
"given": "Gang"
},
"orcid": "0000-0001-9313-251X"
},
{
"id": "Mason-Glenn-M",
"name": {
"family": "Mason",
"given": "Glenn M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "Shih-Albert-Y",
"name": {
"family": "Shih",
"given": "Albert Y."
}
},
{
"id": "Wang-Linghua",
"name": {
"family": "Wang",
"given": "Linghua"
}
}
]
},
"title": "Solar Energetic Particles",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Portions of this work have been supported at JHU/APL by NASA grant NNX17AC05G/125225 and L. W. thanks NSFC for support under grants 41861134033 and 41774183.",
"abstract": "Solar energetic particles (SEPs) have been studied for over seven decades, initially from ground-based instrumentation and now routinely from spacecraft throughout the heliosphere. Our knowledge of the acceleration and transport of these particles from close to the Sun througzh the interplanetary medium has advanced dramatically in the last 40 years as the instrumentation and modeling capabilities have become more sophisticated. However, a full understanding of the conditions and processes that cause variability in SEP event characteristics remains elusive due to the scarcity of in situ measurements well inside 1 AU. This chapter reviews our current understanding of the properties of SEP events, how they are accelerated and transported, and the impact of those processes on event variability. It is not an exhaustive review, but provides a snapshot of the state of our understanding before the near-Sun observations from the Parker Solar Probe and Solar Orbiter missions reveal surprises that challenge this understanding.",
"date": "2021-04-12",
"date_type": "published",
"publisher": "Wiley-American Geophysical Union",
"place_of_pub": "Hoboken, NJ",
"pagerange": "133-178",
"id_number": "CaltechAUTHORS:20220919-979079200",
"isbn": "9781119507536",
"book_title": "Solar Physics and Solar Wind",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220919-979079200",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX17AC05G/125225"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "41861134033"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "41774183"
}
]
},
"other_numbering_system": {
"items": [
{
"id": "1",
"name": "Space physics and aeronomy collection"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1002/9781119815600.ch4",
"pub_year": "2021",
"author_list": "Cohen, Christina M. S.; Li, Gang; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6vsv2-ry133",
"eprint_id": 109320,
"eprint_status": "archive",
"datestamp": "2023-08-20 02:36:17",
"lastmod": "2026-03-30 07:27:19",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Krivonos-Roman-A",
"name": {
"family": "Krivonos",
"given": "Roman"
},
"orcid": "0000-0003-2737-5673"
},
{
"id": "Wik-Daniel",
"name": {
"family": "Wik",
"given": "Daniel"
},
"orcid": "0000-0001-9110-2245"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Perez-Kerstin-M",
"name": {
"family": "Perez",
"given": "Kerstin"
},
"orcid": "0000-0002-6404-4737"
},
{
"id": "Rossland-Steven",
"name": {
"family": "Rossland",
"given": "Steven"
}
},
{
"id": "Sazonov-Sergey",
"name": {
"family": "Sazonov",
"given": "Sergey"
}
},
{
"id": "Zoglauer-Andreas",
"name": {
"family": "Zoglauer",
"given": "Andreas"
},
"orcid": "0000-0001-9067-3150"
}
]
},
"title": "NuSTAR measurement of the cosmic X-ray background in the 3\u201320\u00a0keV energy band",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "instrumentation: detectors \u2013 methods: data analysis \u2013 galaxies: active \u2013 cosmic background radiation \u2013 X-rays:\ngeneral",
"note": "\u00a9 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2021 January 21. Received 2021 January 11; in original form 2020 November 21. Published: 04 February 2021. \n\nThis work has made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NUSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. RK and SS acknowledge support for this research from the Russian Science Foundation (grant 19-12-00396). DW and SR acknowledge support for this work from the NASA Astrophysics Data Analysis Program 80NSSC18K0686. \n\nData Availability: This work is based on the NuSTAR data publicly available through the HEASARC Archive (https://heasarc.gsfc.nasa.gov).\n\nPublished - stab209.pdf
Accepted Version - 2011.11469.pdf
",
"abstract": "We present measurements of the intensity of the cosmic X-ray background (CXB) with the Nuclear Spectroscopic Telescope Array (NuSTAR) telescope in the 3\u201320 keV energy range. Our method uses spatial modulation of the CXB signal on the NuSTAR detectors through the telescope's side aperture. Based on the NuSTAR observations of selected extragalactic fields with a total exposure of 7 Ms, we have estimated the CXB 3\u201320 keV flux to be 2.8 \u00d7 10\u207b\u00b9\u00b9 erg s\u207b\u00b9 cm\u207b\u00b2 deg\u207b\u00b2, which is \u223c8 per cent higher than that measured with HEAO-1 and consistent with the INTEGRAL measurement. The inferred CXB spectral shape in the 3\u201320 keV energy band is consistent with the canonical model of Gruber et al. We demonstrate that the spatially modulated CXB signal measured by NuSTAR is not contaminated by systematic noise and is limited by photon statistics. The measured relative scatter of the CXB intensity between different sky directions is compatible with cosmic variance, which opens new possibilities for studying CXB anisotropy over the whole sky with NuSTAR.",
"date": "2021-04",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "502",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3966-3975",
"id_number": "CaltechAUTHORS:20210601-100040210",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210601-100040210",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Russian Science Foundation",
"grant_number": "19-12-00396"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0686"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stab209",
"primary_object": {
"basename": "2011.11469.pdf",
"url": "https://authors.library.caltech.edu/records/6vsv2-ry133/files/2011.11469.pdf"
},
"related_objects": [
{
"basename": "stab209.pdf",
"url": "https://authors.library.caltech.edu/records/6vsv2-ry133/files/stab209.pdf"
}
],
"pub_year": "2021",
"author_list": "Krivonos, Roman; Wik, Daniel; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zdx4p-hwv63",
"eprint_id": 108496,
"eprint_status": "archive",
"datestamp": "2023-08-22 09:28:22",
"lastmod": "2026-03-30 13:26:55",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hong-Jaesub",
"name": {
"family": "Hong",
"given": "Jaesub"
},
"orcid": "0000-0002-6089-5390"
},
{
"id": "Grindlay-Jonathan-E",
"name": {
"family": "Grindlay",
"given": "Jonathan"
},
"orcid": "0000-0002-1323-5314"
},
{
"id": "Allen-Branden",
"name": {
"family": "Allen",
"given": "Branden"
}
},
{
"id": "Violette-Daniel-P",
"name": {
"family": "Violette",
"given": "Daniel P."
}
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Malta-Dean",
"name": {
"family": "Malta",
"given": "Dean"
}
},
{
"id": "Ovental-Jennifer",
"name": {
"family": "Ovental",
"given": "Jennifer"
}
},
{
"id": "Bordelon-David",
"name": {
"family": "Bordelon",
"given": "David"
}
},
{
"id": "Richter-Daniel",
"name": {
"family": "Richter",
"given": "Daniel"
}
}
]
},
"title": "Proof of concept for through silicon vias in application-specific integrated circuits for hard x-ray imaging detectors",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "application-specific integrated circuits; x-ray; CdZnTe detectors; wire bond; through silicon vias",
"note": "\u00a9 2021 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nPaper 20186 received Dec. 22, 2020; accepted for publication Mar. 12, 2021; published online Apr. 9, 2021. \n\nThis work was supported by NASA APRA Grant No. NNX17AE62G.\n\nPublished - 026001_1.pdf
Accepted Version - 2103.08749.pdf
",
"abstract": "Application-specific integrated circuits (ASICs) are commonly used to efficiently process the signals from sensors and detectors in space. Wire bonding is a space-qualified technique of making interconnections between ASICs and their substrate packaging board for power, control, and readout of the ASICs. Wire bonding is nearly ubiquitous in modern space programs, but their exposed wires can be prone to damage during assembly and subject to electric interference during operations. Additional space around the ASICs needed for wire bonding also impedes efficient packaging of large arrays of detectors. Here, we introduce the through silicon vias (TSV) technology that replaces wire bonds and eliminates their shortcomings. We have successfully demonstrated the feasibility of implementing TSVs to existing ASIC wafers (a.k.a. a via-last process) developed for processing the x-ray signals from the x-ray imaging CdZnTe detectors on the Nuclear Spectroscopic Telescope Array small explorer telescope mission that was launched in 2012. While TSVs are common in the semiconductor industry, this is the first (to our knowledge) successful application for astrophysics imaging instrumentation. We expect that the TSV technology will simplify the detector assembly and thus will enable significant cost and schedule savings in assembly of large area CdZnTe detectors.",
"date": "2021-04",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "7",
"number": "2",
"publisher": "Society of Photo-optical Instrumentation Engineers",
"pagerange": "Art. No. 026001",
"id_number": "CaltechAUTHORS:20210318-162735516",
"issn": "2329-4221",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210318-162735516",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX17AE62G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1117/1.JATIS.7.2.026001",
"primary_object": {
"basename": "026001_1.pdf",
"url": "https://authors.library.caltech.edu/records/zdx4p-hwv63/files/026001_1.pdf"
},
"related_objects": [
{
"basename": "2103.08749.pdf",
"url": "https://authors.library.caltech.edu/records/zdx4p-hwv63/files/2103.08749.pdf"
}
],
"pub_year": "2021",
"author_list": "Hong, Jaesub; Grindlay, Jonathan; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ngt7z-2m898",
"eprint_id": 106902,
"eprint_status": "archive",
"datestamp": "2023-08-22 09:13:25",
"lastmod": "2026-03-30 09:16:13",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Ward-Charlotte-A",
"name": {
"family": "Ward",
"given": "Charlotte"
}
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Mooley-Kunal-Prakash",
"name": {
"family": "Mooley",
"given": "Kunal"
},
"orcid": "0000-0002-2557-5180"
},
{
"id": "De-Kishalay",
"name": {
"family": "De",
"given": "Kishalay"
},
"orcid": "0000-0002-8989-0542"
},
{
"id": "Gezari-Suvi",
"name": {
"family": "Gezari",
"given": "Suvi"
},
"orcid": "0000-0003-3703-5154"
},
{
"id": "van-Velzen-Sjoert",
"name": {
"family": "van Velzen",
"given": "Sjoert"
},
"orcid": "0000-0002-3859-8074"
},
{
"id": "Andreoni-Igor",
"name": {
"family": "Andreoni",
"given": "Igor"
},
"orcid": "0000-0002-8977-1498"
},
{
"id": "Graham-M-J",
"name": {
"family": "Graham",
"given": "Matthew"
},
"orcid": "0000-0002-3168-0139"
},
{
"id": "Masci-Frank-J",
"name": {
"family": "Masci",
"given": "Frank J."
},
"orcid": "0000-0002-8532-9395"
},
{
"id": "Riddle-Reed-L",
"name": {
"family": "Riddle",
"given": "Reed"
},
"orcid": "0000-0002-0387-370X"
},
{
"id": "Zolkower-Jeffry",
"name": {
"family": "Zolkower",
"given": "Jeffry"
}
}
]
},
"title": "A Luminous X-Ray Transient in SDSS J143359.16+400636.0: A Likely Tidal Disruption Event",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Tidal disruption; X-ray transient sources; Transient sources; X-ray sources; Supermassive black holes",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 October 23; revised 2021 January 8; accepted 2021 January 16; published 2021 March 10. \n\nThe majority of this research and manuscript preparation took place during the COVID-19 global pandemic. The authors would like to thank all those who risked their lives as essential workers in order for us to safely continue our work from home. \n\nWe wish to thank the Swift PI, Brad Cenko, for approving the target of opportunity requests we made to observe SDSS J143359.16+400636.0, as well as the rest of the Swift team for carrying the observations out. We also acknowledge the use of public data from the Swift data archive. \n\nWe also wish to thank the NuSTAR PI, Fiona Harrison, for approving the DDT request we made to observe SDSS J143359.16+400636.0, as well as the NuSTAR SOC for carrying out the observation. This work was also supported under NASA contract No. NNG08FD60C. NuSTAR is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nZTF is supported by the National Science Foundation under grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington, Deutsches Elektronen-Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. \n\nThis paper is based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington, Deutsches Elektronen-Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. SED Machine is based on work supported by the National Science Foundation under grant No. 1106171. \n\nThe ZTF forced-photometry service was funded under the Heising-Simons Foundation grant No. 12540303 (PI: Graham). \n\nFacilities: Swift (XRT - , UVOT) - , NuSTAR - , CXO - , Keck:I (LRIS) - , PO:1.2 m PO:1.5 m - , VLA. - \n\nSoftware: CASA (McMullin et al. 2007), CIAO (Fruscione et al. 2006), lpipe (Perley 2019), The Tractor (Lang et al. 2016), XSPEC (Arnaud 1996).\n\nPublished - Brightman_2021_ApJ_909_102.pdf
Submitted - 2010.12587.pdf
",
"abstract": "We present the discovery of a luminous X-ray transient, serendipitously detected by Swift's X-ray Telescope on 2020 February 5, located in the nucleus of the galaxy SDSS J143359.16+400636.0 at z = 0.099 (luminosity distance D_L = 456 Mpc). The transient was observed to reach a peak luminosity of ~10\u2074\u2074 erg s\u207b\u00b9 in the 0.3\u201310 keV X-ray band, which was ~20 times more than the peak optical/UV luminosity. Optical, UV, and X-ray light curves from the Zwicky Transient Facility and Swift show a decline in flux from the source consistent with t^(\u22125/3), and observations with NuSTAR and Chandra show a soft X-ray spectrum with photon index \u0393 = 2.9 \u00b1 0.1. The X-ray/UV properties are inconsistent with well-known active galactic nucleus properties and have more in common with known X-ray tidal disruption events (TDEs), leading us to conclude that it was likely a TDE. The broadband spectral energy distribution can be described well by a disk blackbody model with an inner disk temperature of 7.3^(+0.3)_(\u22120.8) \u00d7 10\u2075 K, with a large fraction (>40%) of the disk emission upscattered into the X-ray band. An optical spectrum taken with Keck/LRIS after the X-ray detection reveals LINER line ratios in the host galaxy, suggesting low-level accretion onto the supermassive black hole prior to the event, but no broad lines or other indications of a TDE were seen. The stellar velocity dispersion implies that the mass of the supermassive black hole powering the event is log(M_(BH)/M_\u2299) = 7.41 \u00b1 0.41, and we estimate that at peak the Eddington fraction of this event was ~50%. This likely TDE was not identified by wide-field optical surveys or optical spectroscopy, indicating that more events like this would be missed without wide-field UV or X-ray surveys.",
"date": "2021-03-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "909",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 102",
"id_number": "CaltechAUTHORS:20201203-151035641",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201203-151035641",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NSF",
"grant_number": "AST-1440341"
},
{
"agency": "ZTF partner institutions"
},
{
"agency": "NSF",
"grant_number": "AST-1106171"
},
{
"agency": "Heising-Simons Foundation",
"grant_number": "12540303"
}
]
},
"local_group": {
"items": [
{
"id": "Infrared-Processing-and-Analysis-Center-(IPAC)"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Zwicky-Transient-Facility"
}
]
},
"doi": "10.3847/1538-4357/abde34",
"primary_object": {
"basename": "Brightman_2021_ApJ_909_102.pdf",
"url": "https://authors.library.caltech.edu/records/ngt7z-2m898/files/Brightman_2021_ApJ_909_102.pdf"
},
"related_objects": [
{
"basename": "2010.12587.pdf",
"url": "https://authors.library.caltech.edu/records/ngt7z-2m898/files/2010.12587.pdf"
}
],
"pub_year": "2021",
"author_list": "Brightman, Murray; Ward, Charlotte; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dw4bc-17b78",
"eprint_id": 108358,
"eprint_status": "archive",
"datestamp": "2023-08-22 09:14:01",
"lastmod": "2026-03-30 14:24:27",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John"
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Hare-Jeremy",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Dauser-Thomas",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Grinberg-Victoria",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Sridhar-Navin",
"name": {
"family": "Sridhar",
"given": "Navin"
},
"orcid": "0000-0002-5519-9550"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kallman-Timothy-R",
"name": {
"family": "Kallman",
"given": "Timothy R."
},
"orcid": "0000-0002-5779-6906"
}
]
},
"title": "Reflection Modeling of the Black Hole Binary 4U 1630\u201347: The Disk Density and Returning Radiation",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Stellar accretion disks; Black hole physics; Atomic physics; Low-mass x-ray binary stars",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 October 14; revised 2021 January 14; accepted 2021 January 15; published 2021 March 12. \n\nWe thank the referee for the helpful comments, each of which facilitated the improvement of this manuscript. \n\nThis work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nR.M.T.C. has been supported by NASA ADAP grant 80NSSC177K0515. J.A.G. acknowledges support from NASA APRA grant 80NSSC17K0345 and from the Alexander von Humboldt Foundation. V.G. is supported through the Margarete von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. J.A.T. acknowledges partial support from NASA ADAP grant 80NSSC19K0586. J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the USRA through a contract with NASA. \n\nThis research has made use of data, software, and/or web tools obtained from the High Energy Astrophysics Science Archive Research Center (HEASARC), a service of the Astrophysics Science Division at NASA/GSFC and of the Smithsonian Astrophysical Observatory's High Energy Astrophysics Division. \n\nThis research has made use of ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/). \n\nFacility: RXTE - Rossi X-ray Timing Explorer (PCA; Jahoda et al. 1996), NuSTAR(Harrison et al. 2013), Swift-XRT (Krimm et al. 2013), HEASARC. \n\nSoftware: XSPEC v.12.10.1s (Arnaud 1996), REFLIONX (Ross & Fabian 2005, 2007), XILLVER (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), RELXILL (v1.3.3; Dauser et al. 2014; Garc\u00eda et al. 2014), PCACORR (Garc\u00eda et al. 2014).\n\nPublished - Connors_2021_ApJ_909_146.pdf
Accepted Version - 2101.06343.pdf
",
"abstract": "We present the analysis of X-ray observations of the black hole binary 4U 1630\u221247 using relativistic reflection spectroscopy. We use archival data from the Rossi X-ray Timing Explorer, Neil Gehrels Swift Observatory, and Nuclear Spectroscopic Telescope Array observatories, taken during different outbursts of the source between 1998 and 2015. Our modeling includes two relatively new advances in modern reflection codes: high-density disks, and returning thermal disk radiation. Accretion disks around stellar-mass black holes are expected to have densities well above the standard value assumed in traditional reflection models (i.e., ne ~ 10\u00b9\u2075 cm\u207b\u00b3). New high-density reflection models have important implications in the determination of disk truncation (i.e., the disk inner radius). This is because one must retain self-consistency in the irradiating flux and corresponding disk ionization state, which is a function of disk density and system geometry. We find that the disk density is n_e \u2265 10\u00b2\u2070 cm\u207b\u00b3 across all spectral states. This density, combined with our constraints on the ionization state of the material, implies an irradiating flux impinging on the disk that is consistent with the expected theoretical estimates. Returning thermal disk radiation\u2014the fraction of disk photons that bend back to the disk producing additional reflection components\u2014is expected predominantly in the soft state. We show that returning radiation models indeed provide a better fit to the soft-state data, reinforcing previous results that show that in the soft state, the irradiating continuum may be blackbody emission from the disk itself.",
"date": "2021-03-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "909",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 146",
"id_number": "CaltechAUTHORS:20210309-080810844",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210309-080810844",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0345"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Margarete von Wrangell Fellowship"
},
{
"agency": "Baden-W\u00fcrttemberg Ministry of Science, Research and the Arts"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0586"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abdd2c",
"primary_object": {
"basename": "2101.06343.pdf",
"url": "https://authors.library.caltech.edu/records/dw4bc-17b78/files/2101.06343.pdf"
},
"related_objects": [
{
"basename": "Connors_2021_ApJ_909_146.pdf",
"url": "https://authors.library.caltech.edu/records/dw4bc-17b78/files/Connors_2021_ApJ_909_146.pdf"
}
],
"pub_year": "2021",
"author_list": "Connors, Riley M. T.; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/c925m-4e165",
"eprint_id": 108320,
"eprint_status": "archive",
"datestamp": "2023-08-22 09:10:31",
"lastmod": "2026-03-29 17:58:40",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "Renee M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Thompson-Ellen-T",
"name": {
"family": "Thompson",
"given": "Ellen T."
},
"orcid": "0000-0002-3669-2294"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Hare-Jeremy",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta D."
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Krivonos-Roman-A",
"name": {
"family": "Krivonos",
"given": "Roman A."
},
"orcid": "0000-0003-2737-5673"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Mastroserio-Guglielmo",
"name": {
"family": "Mastroserio",
"given": "Guglielmo"
},
"orcid": "0000-0003-4216-7936"
},
{
"id": "Slaughter-Catherine-M",
"name": {
"family": "Slaughter",
"given": "Catherine M."
},
"orcid": "0000-0002-5752-3780"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Wik-Daniel",
"name": {
"family": "Wik",
"given": "Daniel"
},
"orcid": "0000-0001-9110-2245"
},
{
"id": "Zoglauer-Andreas",
"name": {
"family": "Zoglauer",
"given": "Andreas"
},
"orcid": "0000-0001-9067-3150"
}
]
},
"title": "StrayCats: A Catalog of NuSTAR Stray Light Observations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray surveys; Astrophysical black holes; Neutron stars; High mass x-ray binary stars; Low-mass x-ray binary stars; Pulsars",
"note": "\u00a9 2021 The American Astronomical Society. \n\nReceived 2020 November 13; revised 2021 January 18; accepted 2021 January 25; published 2021 March 3. \n\nThis work was supported by the National Aeronautics and Space Administration (NASA) under grant No. 80NSSC19K1023 issued through the NNH18ZDA001N Astrophysics Data Analysis Program (ADAP). R.M.L. acknowledges the support of NASA through Hubble Fellowship Program grant HST-HF2-51440.001. R.A.K. acknowledges support from the Russian Science Foundation (grant 19-12-00396). J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the USRA through a contract with NASA. \n\nAdditionally, this work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift - , MAXI - , HEASARC. - \n\nSoftware: astropy (Robitaille et al. 2013; Astropy Collaboration et al. 2018), astroquery (Ginsburg et al. 2019), HEASoft/FTOOLS, IDL, 19 matplotlib (Hunter 2007), numpy, 20 pandas (Pandas Development Team 2020), plotly, 21 scikit-image, 22 Veusz. 23\n\nPublished - Grefenstette_2021_ApJ_909_30.pdf
Accepted Version - 2102.01236.pdf
",
"abstract": "We present StrayCats, a catalog of NuSTAR stray light observations of X-ray sources. Stray light observations arise for sources 1\u00b0\u20134\u00b0 away from the telescope pointing direction. At this off-axis angle, X-rays pass through a gap between the optics and aperture stop and so do not interact with the X-ray optics; instead, they directly illuminate the NuSTAR focal plane. We have systematically identified and examined over 1400 potential observations resulting in a catalog of 436 telescope fields and 78 stray light sources that have been identified. The sources identified include historically known persistently bright X-ray sources, X-ray binaries in outburst, pulsars, and type I X-ray bursters. In this paper, we present an overview of the catalog, how we identified the StrayCats sources, and the analysis techniques required to produce high-level science products. Finally, we present a few brief examples of the science quality of these unique data.",
"date": "2021-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "909",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 30",
"id_number": "CaltechAUTHORS:20210305-073046158",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210305-073046158",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K1023"
},
{
"agency": "NASA",
"grant_number": "NNH18ZDA001N"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "Russian Science Foundation",
"grant_number": "19-12-00396"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/abe045",
"primary_object": {
"basename": "2102.01236.pdf",
"url": "https://authors.library.caltech.edu/records/c925m-4e165/files/2102.01236.pdf"
},
"related_objects": [
{
"basename": "Grefenstette_2021_ApJ_909_30.pdf",
"url": "https://authors.library.caltech.edu/records/c925m-4e165/files/Grefenstette_2021_ApJ_909_30.pdf"
}
],
"pub_year": "2021",
"author_list": "Grefenstette, Brian W.; Ludlam, Renee M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6q2n8-khk11",
"eprint_id": 107933,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:57:47",
"lastmod": "2026-03-30 06:20:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Markwardt-Craig-B",
"name": {
"family": "Markwardt",
"given": "Craig B."
},
"orcid": "0000-0001-9803-3879"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Gotthelf-Eric-V",
"name": {
"family": "Gotthelf",
"given": "Eric V."
},
"orcid": "0000-0003-3847-3957"
},
{
"id": "Kuiper-Lucien",
"name": {
"family": "Kuiper",
"given": "Lucien"
},
"orcid": "0000-0002-7889-6586"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Cook-W-Rick",
"name": {
"family": "Cook",
"given": "W. Rick"
}
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "Andrew"
},
"orcid": "0000-0002-9922-8915"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Roberts-Bryce",
"name": {
"family": "Roberts",
"given": "Bryce"
}
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Timing Calibration of the NuSTAR X-Ray Telescope",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Pulsar timing method; Cross-validation; X-ray detectors; X-ray astronomy; X-ray telescopes; Millisecond pulsars",
"note": "\u00a9 2021 The American Astronomical Society. \n\nReceived 2020 September 16; revised 2020 November 27; accepted 2020 December 7; published 2021 February 23. \n\nM.B. thanks the Fulbright Visiting Scholar Program for supporting a 9 month visit at Caltech. D.J.W. acknowledges financial support from STFC via an Ernest Rutherford fellowship. The authors wish to thank the NuSTAR X-ray Binaries WG, the Magnetars/RPP WG, and the Timing WG, for the hard work and fruitful discussions that led to, and improved, this work; Victoria Kaspi, Jill Burnham, Alessandro Riggio, Andrea Sanna, Paul Ray, Iulia Deneva, Franco Buffa and Alessio Trois for insightful discussions and suggestions. They also wish to thank the referee for their comments, that helped improving the quality of this paper. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, NICER - , HEASARC - . \n\nSoftware: Nustar Clock Utils,15 Stingray (Huppenkothen et al. 2016, 2019), HENDRICS (Bachetti 2018), astropy (Price-Whelan et al. 2018), PINT (Luo et al. 2019), HEASoft/FTOOLS (Blackburn 1995; Blackburn et al. 1999), ATNF pulsar catalog (Manchester et al. 2005), PRESTO (Ransom 2011), corner (Foreman-Mackey 2016), emcee (Foreman-Mackey et al. 2013), IDL.16 Veusz,17 Holoviews.18\n\nPublished - Bachetti_2021_ApJ_908_184.pdf
Accepted Version - 2009.10347.pdf
",
"abstract": "The Nuclear Spectroscopic Telescope Array (NuSTAR) mission is the first focusing X-ray telescope in the hard X-ray (3\u201379 keV) band. Among the phenomena that can be studied in this energy band, some require high time resolution and stability: rotation-powered and accreting millisecond pulsars, fast variability from black holes and neutron stars, X-ray bursts, and more. Moreover, a good alignment of the timestamps of X-ray photons to UTC is key for multi-instrument studies of fast astrophysical processes. In this paper, we describe the timing calibration of the NuSTAR mission. In particular, we present a method to correct the temperature-dependent frequency response of the on-board temperature-compensated crystal oscillator. Together with measurements of the spacecraft clock offsets obtained during downlinks passes, this allows a precise characterization of the behavior of the oscillator. The calibrated NuSTAR event timestamps for a typical observation are shown to be accurate to a precision of ~65 \u03bcs.",
"date": "2021-02-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "908",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 184",
"id_number": "CaltechAUTHORS:20210205-093236142",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210205-093236142",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fulbright Foundation"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/abd1d6",
"primary_object": {
"basename": "2009.10347.pdf",
"url": "https://authors.library.caltech.edu/records/6q2n8-khk11/files/2009.10347.pdf"
},
"related_objects": [
{
"basename": "Bachetti_2021_ApJ_908_184.pdf",
"url": "https://authors.library.caltech.edu/records/6q2n8-khk11/files/Bachetti_2021_ApJ_908_184.pdf"
}
],
"pub_year": "2021",
"author_list": "Bachetti, Matteo; Markwardt, Craig B.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/39yfk-3r750",
"eprint_id": 107587,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:55:58",
"lastmod": "2026-03-29 18:40:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Allen-Robert-C",
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
},
{
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"name": {
"family": "Li",
"given": "G."
},
"orcid": "0000-0001-9313-251X"
},
{
"name": {
"family": "Jian",
"given": "L. K."
},
"orcid": "0000-0002-6849-5527"
},
{
"name": {
"family": "Vines",
"given": "S. K."
},
"orcid": "0000-0002-7515-3285"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Bonnell",
"given": "J. W."
}
},
{
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Filwett",
"given": "R."
},
"orcid": "0000-0002-5497-7867"
},
{
"name": {
"family": "Goetz",
"given": "K."
},
"orcid": "0000-0003-0420-3633"
},
{
"name": {
"family": "Harvey",
"given": "P. R."
},
"orcid": "0000-0002-6938-0166"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Korreck",
"given": "K. E."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Larson",
"given": "D."
},
"orcid": "0000-0001-5030-6030"
},
{
"name": {
"family": "Livi",
"given": "R."
},
"orcid": "0000-0002-0396-0547"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Malaspina",
"given": "D. M."
},
"orcid": "0000-0003-1191-1558"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0002-9745-3502"
},
{
"name": {
"family": "McNutt",
"given": "R."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Paulson",
"given": "K. W."
},
"orcid": "0000-0002-5699-090X"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Raouafi",
"given": "N."
},
"orcid": "0000-0003-2409-3742"
},
{
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"name": {
"family": "Whittlesey",
"given": "P. L."
},
"orcid": "0000-0002-7287-5098"
},
{
"id": "Wiedenbeck-Mark-E",
"name": {
"family": "Wiedenbeck",
"given": "M."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Radial Evolution of a CIR: Observations From a Nearly Radially Aligned Event Between Parker Solar Probe and STEREO-A",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "CIRs; Parker Solar Probe; solar wind; STEREO; suprathermal ions",
"note": "\u00a9 2021 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 01 February 2021; Version of Record online: 01 February 2021; Accepted manuscript online: 14 January 2021; Manuscript accepted: 05 January 2021; Manuscript revised: 28 December 2020; Manuscript received: 21 October 2020. \n\nThis work was supported by the NASA's Parker Solar Probe Mission, contract NNN06AA01C. \n\nData Availability Statement: Parker Solar Probe data can be accessed from https://sppgway.jhuapl.edu/. The STEREO SEPT data are available at http://www2.physik.uni-kiel.de/stereo/data/sept/, and STEREO magnetic field and plasma data can be found at the STEREO Science Center: https://stereo-ssc.nascom.nasa.gov. Wind data are available at https://cdaweb.gsfc.nasa.gov/. This event is taken from the catalog by Allen et al. (2020c).\n\nPublished - 2020GL091376.pdf
",
"abstract": "The addition of Parker Solar Probe (PSP) to the Heliophysics System Observatory has allowed for the unprecedented ability to study Corotating Interaction Regions (CIRs) at multiple radial distances without significant temporal/longitudinal variations. On September 19, 2019, PSP observed a CIR at \u223c0.5 au when it was nearly radially aligned with the Solar Terrestrial Relations Observatory\u2010Ahead (STEREO\u2010A) spacecraft at \u223c1 au, allowing for an unambiguous assessment of the radial evolution of a single CIR. Bulk plasma and magnetic field signatures of the CIR evolve in a fashion characteristic to previous observations; however, the suprathermal ions are enhanced over a larger longitudinal range at PSP than at STEREO\u2010A, although at much lower intensities. The longitudinal spread appears to be largely a consequence of magnetic field line topology at CIRs between the compressed slow solar wind upstream and high\u2010speed stream following the CIR, underscoring the importance of the large\u2010scale topology of these structures.",
"date": "2021-02-16",
"date_type": "published",
"publication": "Geophysical Research Letters",
"volume": "48",
"number": "3",
"publisher": "American Geophysical Union",
"pagerange": "Art. No. e2020GL091376",
"id_number": "CaltechAUTHORS:20210120-094033556",
"issn": "0094-8276",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210120-094033556",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1029/2020gl091376",
"primary_object": {
"basename": "2020GL091376.pdf",
"url": "https://authors.library.caltech.edu/records/39yfk-3r750/files/2020GL091376.pdf"
},
"pub_year": "2021",
"author_list": "Allen, R. C.; Ho, G. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/59dsm-0j486",
"eprint_id": 107934,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:53:24",
"lastmod": "2026-03-29 17:55:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Duncan-Jessie",
"name": {
"family": "Duncan",
"given": "Jessie"
},
"orcid": "0000-0002-6872-4406"
},
{
"id": "Glesener-Lindsay",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Vievering-Juliana-T",
"name": {
"family": "Vievering",
"given": "Juliana"
},
"orcid": "0000-0002-7407-6740"
},
{
"id": "Hannah-Iain-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Smith-David-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
},
{
"id": "Krucker-S\u00e4m",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
},
"orcid": "0000-0002-2002-9180"
},
{
"id": "White-Stephen-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
},
{
"id": "Hudson-Hugh-S",
"name": {
"family": "Hudson",
"given": "Hugh"
},
"orcid": "0000-0001-5685-1283"
}
]
},
"title": "NuSTAR Observation of Energy Release in 11 Solar Microflares",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "The Sun; Solar flare spectra; Solar x-ray flares; Non-thermal radiation sources; Solar flares; Solar physics",
"note": "\u00a9 2021 The American Astronomical Society. \n\nReceived 2020 August 28; revised 2020 October 22; accepted 2020 November 11; published 2021 February 9. \n\nThis work was supported under an NSF Faculty Development Grant (AGS-1429512) to the University of Minnesota, the 2019 NASA Fellowship Program (80NSSC19k1687), an NSF CAREER award (NSF-AGS-1752268), the SolFER DRIVE center (80NSSC20K0627), and the NASA NuSTAR Guest Observer program (80NSSC18K1744). I.G.H is supported by a Royal Society University Fellowship. The authors also wish to thank Pascal Saint-Hilaire for help with eclipse predictions in planning the 2017 August 21 NuSTAR observation.\n\nPublished - Duncan_2021_ApJ_908_29.pdf
Accepted Version - 2011.06651.pdf
",
"abstract": "Solar flares are explosive releases of magnetic energy. Hard X-ray (HXR) flare emission originates from both hot (millions of Kelvin) plasma and nonthermal accelerated particles, giving insight into flare energy release. The Nuclear Spectroscopic Telescope ARray (NuSTAR) utilizes direct-focusing optics to attain much higher sensitivity in the HXR range than that of previous indirect imagers. This paper presents 11 NuSTAR microflares from two active regions (AR 12671 on 2017 August 21 and AR 12712 on 2018 May 29). The temporal, spatial, and energetic properties of each are discussed in context with previously published HXR brightenings. They are seen to display several \"large flare\" properties, such as impulsive time profiles and earlier peak times in higher-energy HXRs. For two events where the active region background could be removed, microflare emission did not display spatial complexity; differing NuSTAR energy ranges had equivalent emission centroids. Finally, spectral fitting showed a high-energy excess over a single thermal model in all events. This excess was consistent with additional higher-temperature plasma volumes in 10/11 microflares and only with an accelerated particle distribution in the last. Previous NuSTAR studies focused on one or a few microflares at a time, making this the first to collectively examine a sizable number of events. Additionally, this paper introduces an observed variation in the NuSTAR gain unique to the extremely low livetime (<1%) regime and establishes a correction method to be used in future NuSTAR solar spectral analysis.",
"date": "2021-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "908",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 29",
"id_number": "CaltechAUTHORS:20210205-093239844",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210205-093239844",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "AGS-1429512"
},
{
"agency": "NASA Postdoctoral Program",
"grant_number": "80NSSC19K1687"
},
{
"agency": "NSF",
"grant_number": "AGS-1752268"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0627"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1744"
},
{
"agency": "Royal Society"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abca3d",
"primary_object": {
"basename": "2011.06651.pdf",
"url": "https://authors.library.caltech.edu/records/59dsm-0j486/files/2011.06651.pdf"
},
"related_objects": [
{
"basename": "Duncan_2021_ApJ_908_29.pdf",
"url": "https://authors.library.caltech.edu/records/59dsm-0j486/files/Duncan_2021_ApJ_908_29.pdf"
}
],
"pub_year": "2021",
"author_list": "Duncan, Jessie; Glesener, Lindsay; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ev2j1-hkp66",
"eprint_id": 108098,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:53:44",
"lastmod": "2026-03-30 14:31:29",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kallman-Timothy-R",
"name": {
"family": "Kallman",
"given": "T."
},
"orcid": "0000-0002-5779-6906"
},
{
"id": "Bautista-Manuel",
"name": {
"family": "Bautista",
"given": "M."
},
"orcid": "0000-0001-6837-3055"
},
{
"id": "Deprince-J\u00e9r\u00f4me",
"name": {
"family": "Deprince",
"given": "J."
},
"orcid": "0000-0002-3409-8232"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Mendoza-Claudio",
"name": {
"family": "Mendoza",
"given": "C."
},
"orcid": "0000-0002-2854-4806"
},
{
"id": "Ogorzalek-Anna",
"name": {
"family": "Ogorzalek",
"given": "A."
},
"orcid": "0000-0003-4504-2557"
},
{
"id": "Palmeri-Patrick",
"name": {
"family": "Palmeri",
"given": "P."
},
"orcid": "0000-0002-4372-6798"
},
{
"id": "Quinet-Pascal",
"name": {
"family": "Quinet",
"given": "P."
},
"orcid": "0000-0002-3937-2640"
}
]
},
"title": "Photoionization Models for High-density Gas",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray astronomy; Atomic physics; X-ray observatories; Atomic spectroscopy",
"note": "\u00a9 2021 The American Astronomical Society. \n\nReceived 2020 August 5; revised 2020 November 9; accepted 2020 November 20; published 2021 February 16. \n\nPartial support for this work was provided by grant 80NSSC17K0345 through the NASA APRA program. J.A.G. acknowledges support from NASA ADAP grant 80NSSC19K0586, and from the Alexander von Humboldt Foundation. J.D. is a Research Fellow of the Belgian Fund for Research Training in Industry and Agriculture (FRIA), while P.P. and P.Q. are, respectively, Research Associate and Research Director of the Belgian Fund for Scientific Research (F.R.S.-FNRS). A.O. is supported by NASA under award number 80GSFC17M0002. We are very grateful to the referee for several constructive suggestions.\n\nPublished - Kallman_2021_ApJ_908_94.pdf
Submitted - 2011.10603.pdf
",
"abstract": "Relativistically broadened and redshifted 6.4\u20136.9 keV iron K lines are observed from many accretion powered objects, including X-ray binaries and active galactic nuclei. The existence of gas close to the central engine implies large radiation intensities and correspondingly large gas densities if the gas is to remain partially ionized. Simple estimates indicate that high gas densities are needed to allow for the survival of iron against ionization. These are high enough that rates for many atomic processes are affected by mechanisms related to interactions with nearby ions and electrons. Radiation intensities are high enough that stimulated processes can be important. Most models currently in use for interpreting relativistic lines use atomic rate coefficients designed for use at low densities and neglect stimulated processes. In our work so far we have presented atomic structure calculations with the goal of providing physically appropriate models at densities consistent with line-emitting gas near compact objects. In this paper we apply these rates to photoionization calculations, and produce ionization balance curves and X-ray emissivities and opacities that are appropriate for high densities and high radiation intensities. The final step in our program will be presented in a subsequent paper in which model atmosphere calculations will incorporate these rates into synthetic spectra.",
"date": "2021-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "908",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 94",
"id_number": "CaltechAUTHORS:20210217-152552788",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210217-152552788",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC17K0345"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0586"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Fonds pour la Formation \u00e0 la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium)"
},
{
"agency": "Fonds de la Recherche Scientifique (FNRS)"
},
{
"agency": "NASA",
"grant_number": "80GSFC17M0002"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abccd6",
"primary_object": {
"basename": "2011.10603.pdf",
"url": "https://authors.library.caltech.edu/records/ev2j1-hkp66/files/2011.10603.pdf"
},
"related_objects": [
{
"basename": "Kallman_2021_ApJ_908_94.pdf",
"url": "https://authors.library.caltech.edu/records/ev2j1-hkp66/files/Kallman_2021_ApJ_908_94.pdf"
}
],
"pub_year": "2021",
"author_list": "Kallman, T.; Bautista, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/1y0p7-5vy53",
"eprint_id": 107937,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:49:47",
"lastmod": "2026-03-29 16:44:48",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Klingler-Noel-J",
"name": {
"family": "Klingler",
"given": "N. J."
},
"orcid": "0000-0002-7465-0941"
},
{
"name": {
"family": "Lien",
"given": "A."
},
"orcid": "0000-0002-7851-9756"
},
{
"name": {
"family": "Oates",
"given": "S. R."
},
"orcid": "0000-0001-9309-7873"
},
{
"name": {
"family": "Kennea",
"given": "J. A."
},
"orcid": "0000-0002-6745-4790"
},
{
"name": {
"family": "Evans",
"given": "P. A."
},
"orcid": "0000-0002-8465-3353"
},
{
"name": {
"family": "Tohuvavohu",
"given": "A."
},
"orcid": "0000-0002-2810-8764"
},
{
"name": {
"family": "Zhang",
"given": "B."
},
"orcid": "0000-0002-9725-2524"
},
{
"name": {
"family": "Page",
"given": "K. L."
},
"orcid": "0000-0001-5624-2613"
},
{
"name": {
"family": "Cenko",
"given": "S. B."
},
"orcid": "0000-0003-1673-970X"
},
{
"name": {
"family": "Barthelmy",
"given": "S. D."
}
},
{
"name": {
"family": "Beardmore",
"given": "A. P."
}
},
{
"name": {
"family": "Bernardini",
"given": "M. G."
},
"orcid": "0000-0001-6106-3046"
},
{
"name": {
"family": "Breeveld",
"given": "A. A."
},
"orcid": "0000-0002-0001-7270"
},
{
"name": {
"family": "Brown",
"given": "P. J."
},
"orcid": "0000-0001-6272-5507"
},
{
"name": {
"family": "Burrows",
"given": "D. N."
},
"orcid": "0000-0003-0729-1632"
},
{
"name": {
"family": "Campana",
"given": "S."
},
"orcid": "0000-0001-6278-1576"
},
{
"name": {
"family": "Cusumano",
"given": "G."
}
},
{
"name": {
"family": "D'A\u00ec",
"given": "A."
},
"orcid": "0000-0002-5042-1036"
},
{
"name": {
"family": "D'Avanzo",
"given": "P."
}
},
{
"name": {
"family": "D'Elia",
"given": "V."
},
"orcid": "0000-0002-7320-5862"
},
{
"name": {
"family": "de Pasquale",
"given": "M."
}
},
{
"name": {
"family": "Emery",
"given": "S. W. K."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Giommi",
"given": "P."
},
"orcid": "0000-0002-2265-5003"
},
{
"name": {
"family": "Gronwall",
"given": "C."
},
"orcid": "0000-0001-6842-2371"
},
{
"name": {
"family": "Hartmann",
"given": "D. H."
},
"orcid": "0000-0002-8028-0991"
},
{
"name": {
"family": "Krimm",
"given": "H. A."
},
"orcid": "0000-0003-4348-6058"
},
{
"name": {
"family": "Kuin",
"given": "N. P. M."
},
"orcid": "0000-0003-4650-4186"
},
{
"name": {
"family": "Malesani",
"given": "D. B."
},
"orcid": "0000-0002-7517-326X"
},
{
"name": {
"family": "Marshall",
"given": "F. E."
},
"orcid": "0000-0002-3559-6305"
},
{
"name": {
"family": "Melandri",
"given": "A."
}
},
{
"name": {
"family": "Nousek",
"given": "J. A."
},
"orcid": "0000-0001-7084-4637"
},
{
"name": {
"family": "O'Brien",
"given": "P. T."
},
"orcid": "0000-0002-5128-1899"
},
{
"name": {
"family": "Osborne",
"given": "J. P."
},
"orcid": "0000-0002-1041-7542"
},
{
"name": {
"family": "Palmer",
"given": "D. M."
},
"orcid": "0000-0001-7128-0802"
},
{
"name": {
"family": "Page",
"given": "M. J."
},
"orcid": "0000-0002-6689-6271"
},
{
"name": {
"family": "Perri",
"given": "M."
},
"orcid": "0000-0003-3613-4409"
},
{
"name": {
"family": "Racusin",
"given": "J. L."
},
"orcid": "0000-0002-4744-9898"
},
{
"name": {
"family": "Sakamoto",
"given": "T."
},
"orcid": "0000-0001-6276-6616"
},
{
"name": {
"family": "Sbarufatti",
"given": "B."
},
"orcid": "0000-0001-6620-8347"
},
{
"name": {
"family": "Schlieder",
"given": "J. E."
},
"orcid": "0000-0001-5347-7062"
},
{
"name": {
"family": "Siegel",
"given": "M. H."
}
},
{
"name": {
"family": "Tagliaferri",
"given": "G."
},
"orcid": "0000-0003-0121-0723"
},
{
"name": {
"family": "Troja",
"given": "E."
},
"orcid": "0000-0002-1869-7817"
}
]
},
"title": "Swift Multiwavelength Follow-up of LVC S200224ca and the Implications for Binary Black Hole Mergers",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Gravitational waves; High energy astrophysics; Black holes; X-ray astronomy; Gamma-ray astronomy; Gamma-ray bursts; Near ultraviolet astronomy",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 November 12; revised 2020 December 7; accepted 2020 December 9; published 2021 February 3. \n\nThis publication is an official product of the Swift GW follow-up team. The authors wish to thank the anonymous referee for helpful comments that enhanced the clarity of the paper. N. J. K. and J. A. K. would like to acknowledge support from NASA Grants 80NSSC19K0408 and 80NSSC20K1104. P. A. E., K. L. P., A. P. B., J. P. O., A. A. B., S. W. K. E., N. P. M. K., and M. J. P. acknowledge funding from the UK Space Agency. P. D. A. acknowledges support from PRIN-MIUR 2017 (grant 20179ZF5KS). M. G. B., G. C., S. C., A. D. A., P. D. A., A. M. and G. T. acknowledge funding from the Italian Space Agency, contract ASI/INAF n. I/004/11/4. The authors would like to acknowledge support from the Italian Ministry of Foreign Affairs and International Cooperation grant MAE0065741. E. T. acknowledges support by the National Aeronautics and Space Administration through grant NNX10AF62G issued through the Astrophysics Data Analysis Program. M. D. P. acknowledges support for this work by the Scientific and Technological Research Council of Turkey (T\u00dcB\u0130TAK), grant No: MFAG-119F073. D. B. M. is supported by research grant 19054 from Villum Fonden. \n\nFacility: NASA Neil Gehrels Swift Observatory.\n\nPublished - Klingler_2021_ApJ_907_97.pdf
Accepted Version - 2012.05384.pdf
",
"abstract": "On 2020 February 24, during their third observing run (\"O3\"), the Laser Interferometer Gravitational-wave Observatory and Virgo Collaboration detected S200224ca: a candidate gravitational wave (GW) event produced by a binary black hole (BBH) merger. This event was one of the best-localized compact binary coalescences detected in O3 (with 50%/90% error regions of 13/72 deg\u00b2), and so the Neil Gehrels Swift Observatory performed rapid near-UV/X-ray follow-up observations. Swift-XRT and UVOT covered approximately 79.2% and 62.4% (respectively) of the GW error region, making S200224ca the BBH event most thoroughly followed-up in near-UV (u-band) and X-ray to date. No likely EM counterparts to the GW event were found by the Swift BAT, XRT, or UVOT, nor by other observatories. Here, we report on the results of our searches for an EM counterpart, both in the BAT data near the time of the merger, and in follow-up UVOT/XRT observations. We also discuss the upper limits we can place on EM radiation from S200224ca, as well as the implications these limits have on the physics of BBH mergers. Namely, we place a shallow upper limit on the dimensionless BH charge, q\u0302 < 1.4 \u00d7 10\u207b\u2074, and an upper limit on the isotropic-equivalent energy of a blast wave E < 4.1 \u00d7 10\u2075\u00b9 erg (assuming typical GRB parameters).",
"date": "2021-02-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "907",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 97",
"id_number": "CaltechAUTHORS:20210205-145940595",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210205-145940595",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K0408"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1104"
},
{
"agency": "United Kingdom Space Agency (UKSA)"
},
{
"agency": "Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR)",
"grant_number": "20179ZF5KS"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/004/11/4"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Ministry of Foreign Affairs and International Cooperation (MAECI)",
"grant_number": "MAE0065741"
},
{
"agency": "NASA",
"grant_number": "NNX10AF62G"
},
{
"agency": "T\u00fcrkiye Bilimsel ve Teknolojik Ara\u015ft\u0131rma Kurumu (T\u00dcB\u0130TAK)",
"grant_number": "MFAG-119F073"
},
{
"agency": "VILLUM FONDEN",
"grant_number": "19054"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abd2c3",
"primary_object": {
"basename": "2012.05384.pdf",
"url": "https://authors.library.caltech.edu/records/1y0p7-5vy53/files/2012.05384.pdf"
},
"related_objects": [
{
"basename": "Klingler_2021_ApJ_907_97.pdf",
"url": "https://authors.library.caltech.edu/records/1y0p7-5vy53/files/Klingler_2021_ApJ_907_97.pdf"
}
],
"pub_year": "2021",
"author_list": "Klingler, N. J.; Lien, A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/fe3d5-mnk59",
"eprint_id": 107840,
"eprint_status": "archive",
"datestamp": "2023-08-20 01:41:26",
"lastmod": "2026-03-30 06:26:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Evans-Philip-A",
"name": {
"family": "Evans",
"given": "P. A."
},
"orcid": "0000-0002-8465-3353"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Israel-GianLuca",
"name": {
"family": "Israel",
"given": "G. L."
},
"orcid": "0000-0001-5480-6438"
},
{
"id": "Lansbury-George-B",
"name": {
"family": "Lansbury",
"given": "G. B."
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "S."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Rana-Vikram-R",
"name": {
"family": "Rana",
"given": "V."
},
"orcid": "0000-0003-1703-8796"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Rodriguez-Castillo-G-A",
"name": {
"family": "Rodriguez\u00a0Castillo",
"given": "G. A."
}
},
{
"id": "Salvaterra-Ruben",
"name": {
"family": "Salvaterra",
"given": "R."
},
"orcid": "0000-0002-9393-8078"
},
{
"id": "Song-Xiaoxi",
"name": {
"family": "Song",
"given": "X."
},
"orcid": "0000-0003-4924-0550"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
}
]
},
"title": "A new transient ultraluminous X-ray source in NGC\u20097090",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: black holes \u2013 stars: neutron \u2013 X-rays: binaries \u2013 X-rays: individual (NGC 7090 ULX3)",
"note": "\u00a9 2020 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 November 18. Received 2020 November 17; in original form 2020 October 9. Published: 25 November 2020. \n\nThe authors would like to thank the reviewer for their positive feedback, which helped to improve the final version of the manuscript. DJW and MJM acknowledge support from the Science and Technology Facilities Council (STFC) in the form of Ernest Rutherford Fellowships. PAE acknowledges UK Space Agency (UKSA) support. This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by the NASA Jet Propulsion Laboratory (JPL), and has utilized the NUSTARDAS software package, jointly developed by the Space Science Data Centre (SSDC; Italy) and Caltech (USA). This research has also made use of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States, as well as public data from the Swift data archive. Finally, this work has also made use of data obtained from the Chandra Source Catalog, provided by the Chandra X-ray Center (CXC) as part of the Chandra Data Archive, as well as data obtained from the 4XMM XMM-Newton serendipitous source catalogue, compiled by the 10 institutes of the XMM-Newton Survey Science Centre (SSC) selected by ESA. \n\nData Availability: All of the data underlying this article are either already publicly available from ESA's XMM\u2013Newton Science Archive (https://www.cosmos.esa.int/web/xmm-newton/xsa), NASA's HEASARC archive (https://heasarc.gsfc.nasa.gov/), and NASA's Chandra Data Archive (https://cxc.harvard.edu/cda/), or will be from 2021 May.\n\nPublished - staa3666.pdf
Accepted Version - 2011.08870.pdf
",
"abstract": "We report on the discovery of a new, transient ultraluminous X-ray source (ULX) in the galaxy NGC\u20097090. This new ULX, which we refer to as NGC\u20097090 ULX3, was discovered via monitoring with Swift during 2019\u20132020, and to date has exhibited a peak luminosity of L_X \u223c 6 \u00d7 10\u00b3\u2079 erg s\u207b\u00b9. Archival searches show that, prior to its recent transition into the ULX regime, ULX3 appeared to exhibit a fairly stable luminosity of L_X \u223c 10\u00b3\u2078 erg s\u207b\u00b9. Such strong long-time-scale variability may be reminiscent of the small population of known ULX pulsars, although deep follow-up observations with XMM\u2013Newton and NuSTAR do not reveal any robust X-ray pulsation signals. Pulsations similar to those seen from known ULX pulsars cannot be completely excluded, however, as the limit on the pulsed fraction of any signal that remains undetected in these data is \u227220 per cent. The broad-band spectrum from these observations is well modelled with a simple thin disc model, consistent with sub-Eddington accretion, which may instead imply a moderately large black hole accretor (M_(BH) \u223c 40\u2009M\u2299). Similarly, though, more complex models consistent with the super-Eddington spectra seen in other ULXs (and the known ULX pulsars) cannot be excluded given the limited signal-to-noise ratio of the available broad-band data. The nature of the accretor powering this new ULX therefore remains uncertain.",
"date": "2021-02",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "501",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "1002-1012",
"id_number": "CaltechAUTHORS:20210201-140020702",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210201-140020702",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "United Kingdom Space Agency (UKSA)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/staa3666",
"primary_object": {
"basename": "staa3666.pdf",
"url": "https://authors.library.caltech.edu/records/fe3d5-mnk59/files/staa3666.pdf"
},
"related_objects": [
{
"basename": "2011.08870.pdf",
"url": "https://authors.library.caltech.edu/records/fe3d5-mnk59/files/2011.08870.pdf"
}
],
"pub_year": "2021",
"author_list": "Walton, D. J.; Heida, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/hhjz6-ttk39",
"eprint_id": 107961,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:45:33",
"lastmod": "2026-03-30 04:47:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Strittmatter-Benjamin",
"name": {
"family": "Strittmatter",
"given": "Benjamin"
},
"orcid": "0000-0002-7606-3679"
},
{
"id": "Lamperti-Isabella",
"name": {
"family": "Lamperti",
"given": "Isabella"
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Shimizu-Taro",
"name": {
"family": "Shimizu",
"given": "Taro"
},
"orcid": "0000-0002-2125-4670"
},
{
"id": "Trakhtenbrot-Benny",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Saintonge-Amelie",
"name": {
"family": "Saintonge",
"given": "Amelie"
},
"orcid": "0000-0003-4357-3450"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Cicone-Claudia",
"name": {
"family": "Cicone",
"given": "Claudia"
},
"orcid": "0000-0003-0522-6941"
},
{
"id": "Mushotzky-Richard-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Ananna-Tonima-Tasnim",
"name": {
"family": "Ananna",
"given": "Tonima Tasnim"
},
"orcid": "0000-0001-8211-3807"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "B\u00e4r-Rudolf-E",
"name": {
"family": "B\u00e4r",
"given": "Rudolf E."
},
"orcid": "0000-0001-5481-8607"
},
{
"id": "De-Breuck-Carlos",
"name": {
"family": "De Breuck",
"given": "Carlos"
},
"orcid": "0000-0002-6637-3315"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "Meredith C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Rosario-David",
"name": {
"family": "Rosario",
"given": "David"
},
"orcid": "0000-0002-0001-3587"
},
{
"id": "Sanders-David-B",
"name": {
"family": "Sanders",
"given": "David B."
},
"orcid": "0000-0002-1233-9998"
},
{
"id": "Schawinski-Kevin",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
},
{
"id": "Shao-Li",
"name": {
"family": "Shao",
"given": "Li"
},
"orcid": "0000-0003-2015-777X"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Veilleux-S",
"name": {
"family": "Veilleux",
"given": "Sylvain"
},
"orcid": "0000-0002-3158-6820"
}
]
},
"title": "BAT AGN Spectroscopic Survey. XX. Molecular Gas in Nearby Hard-X-Ray-selected AGN Galaxies",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; AGN host galaxies; Molecular gas; Surveys; X-ray active galactic nuclei; Survival analysis; Submillimeter astronomy; High energy astrophysics; Seyfert galaxies; Catalogs",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 February 21; revised 2020 October 10; accepted 2020 October 19; published 2021 February 4. \n\nWe acknowledge support from NASA through ADAP award NNH16CT03C and 80NSSC19K0749 (M.K.); the Israel Science Foundation through grant No. 1849/19 (B.T.); the Royal Society through the award of a University Research Fellowship (A.S.); ANID grants PIA ACT172033 (E.T.), Basal-CATA PFB-06/2007 and AFB170002 grants (E.T., F.E.B.), FONDECYT Regular 1160999, 1190818 (E.T., F.E.B.), and 1200495 (E.T., F.E.B.), and Millennium Science Initiative ICN12_009 (F.E.B.); the National Research Foundation of Korea (NRF-2020R1C1C1005462) (K.O.), the Japan Society for the Promotion of Science JSPS ID:17321 (K.O.); the ANID+PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080 (C.R.); the UK Science and Technology Facilities Council through grants ST/P000541/1 and ST/T000244/1 (D.R.); and the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA (D.S.). We acknowledge the work that Swift-BAT team has done to make this project possible. We acknowledge the help of Rozenn Boissay-Malaquin. \n\nThis publication is based on data acquired with the Atacama Pathfinder Experiment (APEX). APEX is a collaboration between the Max-Planck-Institut fur Radioastronomie, the European Southern Observatory, and the Onsala Space Observatory. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 198.A-0708(A), 0100.A-0384(A), 097.B-0757(A), 098.B-0152(A), 081.F-9405(A), and 091.F-9313(A) as well as Chilean programs C-097.F-9705A-2016, C-098.F-9700-2016, and C-0100.F-9715. The James Clerk Maxwell Telescope is operated by the East Asian Observatory on behalf of The National Astronomical Observatory of Japan; Academia Sinica Institute of Astronomy and Astrophysics; the Korea Astronomy and Space Science Institute; Center for Astronomical Mega-Science (as well as the National Key R&D Program of China with No. 2017YFA0402700). Additional funding support is provided by the Science and Technology Facilities Council of the United Kingdom and participating universities in the United Kingdom and Canada. This project involved JCMT programs M11AH42C, M11BH35C, M12AH35C, M12BH03E, and M09BH34B. The Starlink software (Currie et al. 2014) is currently supported by the East Asian Observatory. This research made use of: the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration and the SIMBAD database, operated at CDS, Strasbourg, France (Wenger et al. 2000). \n\nFacilities: APEX - Atacama Pathfinder Experiment, JCMT - , PS1 - , Swift (BAT). - \n\nSoftware: astropy (Collaboration et al. 2013), APLpy (Robitaille & Bressert 2012), CIAO (v4.11, Fruscione et al. 2006), GILDAS (Pety 2005; Gildas Team 2013), lifelines (version 0.25.4, Davidson-Pilon et al. 2020), Matplotlib (Hunter 2007), Numpy (Harris et al. 2020), Sherpa (v4.12.1, Freeman et al. 2001; Burke & Laurino 2020), Starlink (Currie et al. 2014).\n\nPublished - Koss_2021_ApJS_252_29.pdf
Accepted Version - 2010.15849.pdf
",
"abstract": "We present the host-galaxy molecular gas properties of a sample of 213 nearby (0.01 < z < 0.05) hard-X-ray-selected active galactic nucleus (AGN) galaxies, drawn from the 70-month catalog of Swift's Burst Alert Telescope (BAT), with 200 new CO(2\u20131) line measurements obtained with the James Clerk Maxwell Telescope and the Atacama Pathfinder Experiment telescope. We find that AGN in massive galaxies (log (M_*/M_\u2299) > 10.5) tend to have more molecular gas and higher gas fractions than inactive galaxies matched in stellar mass. When matched in star formation, we find AGN galaxies show no difference from inactive galaxies, with no evidence that AGN feedback affects the molecular gas. The higher molecular gas content is related to AGN galaxies hosting a population of gas-rich early types with an order of magnitude more molecular gas and a smaller fraction of quenched, passive galaxies (~5% versus 49%) compared to inactive galaxies. The likelihood of a given galaxy hosting an AGN (L_(bol) > 10\u2074\u2074 erg s\u207b\u00b9 ) increases by ~10\u2013100 between a molecular gas mass of 10^(8.7) M_\u2299 and 10^(10.2) M_\u2299. AGN galaxies with a higher Eddington ratio (log(L/L_(Edd)) > \u22121.3) tend to have higher molecular gas masses and gas fractions. The log(N_H/ cm\u207b\u00b2 ) > 23.4) of AGN galaxies with higher column densities are associated with lower depletion timescales and may prefer hosts with more gas centrally concentrated in the bulge that may be more prone to quenching than galaxy-wide molecular gas. The significant average link of host-galaxy molecular gas supply to supermassive black hole (SMBH) growth may naturally lead to the general correlations found between SMBHs and their host galaxies, such as the correlations between SMBH mass and bulge properties, and the redshift evolution of star formation and SMBH growth.",
"date": "2021-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "252",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 29",
"id_number": "CaltechAUTHORS:20210208-144011011",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210208-144011011",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0749"
},
{
"agency": "Israel Science Foundation",
"grant_number": "1849/19"
},
{
"agency": "Royal Society"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PIA ACT172033"
},
{
"agency": "Basal-CATA",
"grant_number": "PFB-06/2007"
},
{
"agency": "Basal-CATA",
"grant_number": "AFB170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1160999"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "ICN12_009"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PAI77170080"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/P000541/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T000244/1"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2017YFA0402700"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/abcbfe",
"primary_object": {
"basename": "2010.15849.pdf",
"url": "https://authors.library.caltech.edu/records/hhjz6-ttk39/files/2010.15849.pdf"
},
"related_objects": [
{
"basename": "Koss_2021_ApJS_252_29.pdf",
"url": "https://authors.library.caltech.edu/records/hhjz6-ttk39/files/Koss_2021_ApJS_252_29.pdf"
}
],
"pub_year": "2021",
"author_list": "Koss, Michael J.; Strittmatter, Benjamin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4w0sm-6pd09",
"eprint_id": 107839,
"eprint_status": "archive",
"datestamp": "2023-08-20 01:41:19",
"lastmod": "2026-03-30 09:00:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Cheng-Huaqing",
"name": {
"family": "Cheng",
"given": "Huaqing"
},
"orcid": "0000-0003-4200-9954"
},
{
"id": "Gallo-Luigi-C",
"name": {
"family": "Gallo",
"given": "Luigi C."
}
},
{
"id": "Ho-Luis-C",
"name": {
"family": "Ho",
"given": "Luis C."
},
"orcid": "0000-0001-6947-5846"
},
{
"id": "Buisson-Douglas-J-K",
"name": {
"family": "Buisson",
"given": "Douglas J. K."
}
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Reynolds-Christopher-S",
"name": {
"family": "Reynolds",
"given": "Christopher S."
}
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Yuan-Weimin",
"name": {
"family": "Yuan",
"given": "Weimin"
}
}
]
},
"title": "The awakening beast in the Seyfert 1 Galaxy KUG\u00a01141+371 \u2013 I",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013 black hole physics \u2013 galaxies: Seyfert \u2013X-rays: galaxies",
"note": "\u00a9 2020 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 November 27. Received 2020 November 8; in original form 2020 March 6. Published: 03 December 2020. \n\nThis paper was written during the outbreak of COVID-19 in China in 2020. We would like to acknowledge the doctors and nurses who have been working day and night to ensure the safety of Chinese people during this period. JJ acknowledges support from the Tsinghua Astrophysics Outstanding Fellowship and the Tsinghua Shuimu Scholar Program. LCH acknowledges support from National Science Foundation of China (11721303, 11991052) and National Key Research and Development Program of China (2016YFA0400702). DJKB acknowledges support from Royal Society. ACF acknowledges support from ERC Advanced Grant (340442). CSR thanks the UK Science and Technology Facilities Council for support under the New Applicant grant ST/R000867/1, and the European Research Council for support under the European Union's Horizon 2020 research and innovation programme (834203). MLP is supported by European Space Agency Research Fellowships. DJW acknowledges support from an STFC Ernest Rutherford Fellowship. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. This research has made use of the NuSTAR Data Analysis Software (NUSTARDAS) jointly developed by the ASI Science Data Center and the California Institute of Technology. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This project was also based on observations obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This project has made use of the Science Analysis Software (SAS), an extensive suite to process the data collected by the XMM\u2013Newton observatory. HQ acknowledges support from National Natural Science Foundation of China (11803047). \n\nData Availability: The data underlying this article are available in the High Energy Astrophysics Science Archive Research Center (HEASARC), at https://heasarc.gsfc.nasa.gov.\n\nPublished - staa3737.pdf
Accepted Version - 2011.14254.pdf
",
"abstract": "KUG 1141+371 is a Seyfert 1 galaxy that shows a simultaneous flux increase in the optical and UV bands in the past decade. For instance, the latest Swift observation in 2019 shows that the UVW2 flux of the active galactic nucleus in KUG 1141+371 has increased by over one order of magnitude since 2009. Meanwhile, the soft X-ray flux of KUG 1141+371 also shows a steady increase by one order of magnitude since 2007. The significant multiwavelength luminosity change is likely due to a boost of mass accretion rate from approximately 0.6 per cent of the Eddington limit to 3.2 per cent\u2060, assuming a black hole mass of 10\u2078\u2009M\u2299. In this work, we conduct detailed multi-epoch X-ray spectral analysis focusing on the variability of the X-ray continuum emission and the puzzling soft excess emission. In addition, our SED models also suggest a simultaneous increase of disc temperature and a decreasing inner disc radius along with the increasing accretion rate. Finally, we discuss possible connection between KUG 1141+371 and black hole transients in outburst.",
"date": "2021-02",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "501",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "916-932",
"id_number": "CaltechAUTHORS:20210201-134244580",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210201-134244580",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Tsinghua University"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11721303"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11991052"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400702"
},
{
"agency": "Royal Society"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/R000867/1"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "834203"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11803047"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa3737",
"primary_object": {
"basename": "2011.14254.pdf",
"url": "https://authors.library.caltech.edu/records/4w0sm-6pd09/files/2011.14254.pdf"
},
"related_objects": [
{
"basename": "staa3737.pdf",
"url": "https://authors.library.caltech.edu/records/4w0sm-6pd09/files/staa3737.pdf"
}
],
"pub_year": "2021",
"author_list": "Jiang, Jiachen; Cheng, Huaqing; et al."
},
{
"id": "https://authors.library.caltech.edu/records/v0vrq-80s08",
"eprint_id": 107658,
"eprint_status": "archive",
"datestamp": "2023-08-20 01:29:14",
"lastmod": "2026-03-29 21:19:57",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xiao-Mengjiao",
"name": {
"family": "Xiao",
"given": "Mengjiao"
},
"orcid": "0000-0002-6397-617X"
},
{
"id": "Perez-Kerstin-M",
"name": {
"family": "Perez",
"given": "Kerstin M."
},
"orcid": "0000-0002-6404-4737"
},
{
"id": "Giannotti-Maurizio",
"name": {
"family": "Giannotti",
"given": "Maurizio"
},
"orcid": "0000-0001-9823-6262"
},
{
"id": "Straniero-Oscar",
"name": {
"family": "Straniero",
"given": "Oscar"
},
"orcid": "0000-0002-5514-6125"
},
{
"id": "Mirizzi-Alessandro",
"name": {
"family": "Mirizzi",
"given": "Alessandro"
},
"orcid": "0000-0002-5382-3786"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Roach-Brandon-M",
"name": {
"family": "Roach",
"given": "Brandon M."
},
"orcid": "0000-0003-3841-6290"
},
{
"id": "Nynka-Melania",
"name": {
"family": "Nynka",
"given": "Melania"
},
"orcid": "0000-0002-3310-1946"
}
]
},
"title": "Constraints on Axionlike Particles from a Hard X-Ray Observation of Betelgeuse",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2021 American Physical Society. \n\n(Received 14 October 2020; revised 28 November 2020; accepted 11 December 2020; published 21 January 2021) \n\nWe thank D.\u2009R. Wik and S. Rossland for helpful discussions on the NuSTAR instrument background; J.\u2009L. Han and S. Zhang for discussions concerning the Galactic magnetic field in the direction of Betelgeuse; Benjamin Safdi, Christopher Dessert, John Beacom, Shunsaku Horiuchi, and Kenny C.\u2009Y. Ng for helpful comments and discussions. The NuSTAR observations described in this work were awarded under NASA Grant No. 80NSSC20K0031. The computational aspects of this work made extensive use of the following packages: saoimage ds9 distributed by the Smithsonian Astrophysical Observatory; the scipy ecosystem, particularly matplotlib and numpy; and astropy, a community-developed core python package for Astronomy. This research has made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). M.\u2009X. and M.\u2009G. were supported by NASA Grant No. 80NSSC20K0031. O.\u2009S. has been supported by the Agenzia Spaziale Italiana (ASI) and the Instituto Nazionale di Astrofsica (INAF) under the Agreement No. 2017-14-H.0\u2014attivit\u00e0 di studio per la comunit\u00e0 scientifica di Astrofisica delle Alte Energie e Fisica Astroparticellare. A.\u2009M. is partially supported by the Italian Istituto Nazionale di Fisica Nucleare (INFN) through the \"Theoretical Astroparticle Physics\" project and by the research Grant No. 2017W4HA7S \"NAT-NET: Neutrino and Astroparticle Theory Network\" under the program PRIN 2017 funded by the Italian Ministero dell'Universit\u00e0 e della Ricerca (MUR). B.\u2009G. was supported under NASA Contract No. NNG08FD60C.\n\nPublished - PhysRevLett.126.031101.pdf
Accepted Version - 2009.09059.pdf
Supplemental Material - Betelgeuse_ALP_SM.pdf
",
"abstract": "We use the first observation of Betelgeuse in hard x rays to perform a novel search for axionlike particles (ALPs). Betelgeuse is not expected to be a standard source of x rays, but light ALPs produced in the stellar core could be converted back into photons in the Galactic magnetic field, producing a detectable flux that peaks in the hard x-ray band (E_\u03b3 > 10 keV). Using a 50 ks observation of Betelgeuse by the NuSTAR satellite telescope, we find no significant excess of events above the expected background. Using models of the regular Galactic magnetic field in the direction of Betelgeuse, we set a 95% C.L. upper limit on the ALP-photon coupling of g_(a\u03b3) < (0.5\u20131.8) \u00d7 10\u207b\u00b9\u00b9 GeV\u207b\u00b9 (depending on magnetic field model) for ALP masses m_a < (5.5\u20133.5) \u00d7 10 \u207b\u00b9\u00b9 eV.",
"date": "2021-01-22",
"date_type": "published",
"publication": "Physical Review Letters",
"volume": "126",
"number": "3",
"publisher": "American Physical Society",
"pagerange": "Art. No. 031101",
"id_number": "CaltechAUTHORS:20210122-092204482",
"issn": "0031-9007",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210122-092204482",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K0031"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "2017-14-H.0"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)",
"grant_number": "2017W4HA7S"
},
{
"agency": "Ministero dell'Universit\u00e0 e della Ricerca (MUR)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1103/physrevlett.126.031101",
"primary_object": {
"basename": "2009.09059.pdf",
"url": "https://authors.library.caltech.edu/records/v0vrq-80s08/files/2009.09059.pdf"
},
"related_objects": [
{
"basename": "Betelgeuse_ALP_SM.pdf",
"url": "https://authors.library.caltech.edu/records/v0vrq-80s08/files/Betelgeuse_ALP_SM.pdf"
},
{
"basename": "PhysRevLett.126.031101.pdf",
"url": "https://authors.library.caltech.edu/records/v0vrq-80s08/files/PhysRevLett.126.031101.pdf"
}
],
"pub_year": "2021",
"author_list": "Xiao, Mengjiao; Perez, Kerstin M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/abj4z-7ss59",
"eprint_id": 107523,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:25:55",
"lastmod": "2026-03-30 16:45:33",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Richardson-John-D",
"name": {
"family": "Richardson",
"given": "J. D."
},
"orcid": "0000-0003-4041-7540"
},
{
"id": "Heikkila-Bryant-C",
"name": {
"family": "Heikkila",
"given": "B. C."
}
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "N."
}
},
{
"id": "K\u00f3ta-Jozsef",
"name": {
"family": "K\u00f3ta",
"given": "J."
},
"orcid": "0000-0002-3715-0358"
}
]
},
"title": "No Stagnation Region before the Heliopause at Voyager 1? Inferences from New Voyager 2 Results",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliosphere; Solar wind; Heliosheath; Cosmic rays",
"note": "\u00a9 2021. The American Astronomical Society. \n\nReceived 2020 August 31; revised 2020 October 16; accepted 2020 October 27; published 2021 January 15. \n\nA.C.C., E.C.S., N.L., and B.C.H. acknowledge Voyager data analysis support from NASA award number NNN12AA01C. J.D.R. was supported under NASA contract 959203 from the Jet Propulsion Laboratory to the Massachusetts Institute of Technology. A.C.C. and J.D.R. also acknowledge support by NASA grant 18-DRIVE_2-0029, Our Heliospheric Shield, 80NSSC20K0603.\n\nPublished - Cummings_2021_ApJ_906_126.pdf
Accepted Version - 2011.12926.pdf
",
"abstract": "We present anisotropy results for anomalous cosmic-ray protons in the energy range ~0.5\u201335 MeV from Cosmic Ray Subsystem (CRS) data collected during calibration roll maneuvers for the magnetometer instrument when Voyager 2 (V2) was in the inner heliosheath. We use a new technique to derive for the first time the radial component of the anisotropy vector from CRS data. We find that the CRS-derived radial solar wind speeds, when converted from the radial components of the anisotropy vectors via the Compton\u2013Getting (C\u2013G) effect, generally agree with those similarly derived speeds from the Low Energy Charged Particle experiment using 28\u201343 keV data. However, they often differ significantly from the radial solar wind speeds measured directly by the Plasma Science (PLS) instrument. There are both periods when the C\u2013G-derived radial solar wind speeds are significantly higher than those measured by PLS and times when they are significantly lower. The differences are not expected nor explained, but it appears that after a few years in the heliosheath the V2 radial solar wind speeds derived from the C\u2013G method underestimate the true speeds as the spacecraft approaches the heliopause. We discuss the implications of this observation for the stagnation region reported along the Voyager 1 trajectory as it approached the heliopause inferred using the C\u2013G method.",
"date": "2021-01-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "906",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 126",
"id_number": "CaltechAUTHORS:20210115-152850922",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210115-152850922",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "JPL",
"grant_number": "959203"
},
{
"agency": "NASA",
"grant_number": "18-DRIVE_2-0029"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0603"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abc5c0",
"primary_object": {
"basename": "Cummings_2021_ApJ_906_126.pdf",
"url": "https://authors.library.caltech.edu/records/abj4z-7ss59/files/Cummings_2021_ApJ_906_126.pdf"
},
"related_objects": [
{
"basename": "2011.12926.pdf",
"url": "https://authors.library.caltech.edu/records/abj4z-7ss59/files/2011.12926.pdf"
}
],
"pub_year": "2021",
"author_list": "Cummings, A. C.; Stone, E. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/c4tzy-2eg85",
"eprint_id": 107445,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:24:00",
"lastmod": "2026-03-30 14:33:42",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wang-Yanan",
"name": {
"family": "Wang",
"given": "Yanan"
}
},
{
"name": {
"family": "Ji",
"given": "Long"
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"name": {
"family": "M\u00e9ndez",
"given": "Mariano"
}
},
{
"name": {
"family": "Mao",
"given": "Junjie"
}
},
{
"name": {
"family": "Tao",
"given": "L."
},
"orcid": "0000-0002-2705-4338"
},
{
"name": {
"family": "Altamirano",
"given": "Diego"
},
"orcid": "0000-0002-3422-0074"
},
{
"name": {
"family": "Maggi",
"given": "Pierre"
}
},
{
"name": {
"family": "Zhang",
"given": "S. N."
},
"orcid": "0000-0001-5586-1017"
},
{
"name": {
"family": "Ge",
"given": "M. Y."
},
"orcid": "0000-0002-2749-6638"
},
{
"name": {
"family": "Zhang",
"given": "L."
},
"orcid": "0000-0003-4498-9925"
},
{
"name": {
"family": "Qu",
"given": "J. L."
},
"orcid": "0000-0002-9796-2585"
},
{
"name": {
"family": "Zhang",
"given": "S."
}
},
{
"name": {
"family": "Ma",
"given": "X."
}
},
{
"name": {
"family": "Lu",
"given": "F. J."
},
"orcid": "0000-0003-3248-6087"
},
{
"name": {
"family": "Li",
"given": "T. P."
}
},
{
"name": {
"family": "Huang",
"given": "Y."
}
},
{
"name": {
"family": "Zheng",
"given": "S. J."
}
},
{
"name": {
"family": "Chang",
"given": "Z."
}
},
{
"name": {
"family": "Tuo",
"given": "Y. L."
}
},
{
"name": {
"family": "Song",
"given": "L. M."
}
},
{
"name": {
"family": "Xu",
"given": "Y. P."
}
},
{
"name": {
"family": "Chen",
"given": "Y."
},
"orcid": "0000-0001-9834-2196"
},
{
"name": {
"family": "Liu",
"given": "C. Z."
}
},
{
"name": {
"family": "Bu",
"given": "Q. C."
},
"orcid": "0000-0001-5238-3988"
},
{
"name": {
"family": "Cai",
"given": "C."
}
},
{
"name": {
"family": "Cao",
"given": "X. L."
}
},
{
"name": {
"family": "Chen",
"given": "L."
}
},
{
"name": {
"family": "Chen",
"given": "T. X."
}
},
{
"name": {
"family": "Chen",
"given": "Y. P."
}
},
{
"name": {
"family": "Cui",
"given": "W. W."
}
},
{
"name": {
"family": "Du",
"given": "Y. Y."
}
},
{
"name": {
"family": "Gao",
"given": "G. H."
}
},
{
"name": {
"family": "Gu",
"given": "Y. D."
}
},
{
"name": {
"family": "Guan",
"given": "J."
}
},
{
"name": {
"family": "Guo",
"given": "C. C."
}
},
{
"name": {
"family": "Han",
"given": "D. W."
}
},
{
"name": {
"family": "Huo",
"given": "J."
}
},
{
"name": {
"family": "Jia",
"given": "S. M."
},
"orcid": "0000-0002-5203-8321"
},
{
"name": {
"family": "Jiang",
"given": "W. C."
}
},
{
"name": {
"family": "Jin",
"given": "J."
}
},
{
"name": {
"family": "Kong",
"given": "L. D."
},
"orcid": "0000-0003-3188-9079"
},
{
"name": {
"family": "Li",
"given": "B."
},
"orcid": "0000-0002-0238-834X"
},
{
"name": {
"family": "Li",
"given": "C. K."
},
"orcid": "0000-0001-5798-4491"
},
{
"name": {
"family": "Li",
"given": "G."
},
"orcid": "0000-0001-5067-1599"
},
{
"name": {
"family": "Li",
"given": "W."
}
},
{
"name": {
"family": "Li",
"given": "X."
}
},
{
"name": {
"family": "Li",
"given": "X. B."
}
},
{
"name": {
"family": "Li",
"given": "X. F."
},
"orcid": "0000-0002-2793-9857"
},
{
"name": {
"family": "Li",
"given": "Z. W."
}
},
{
"name": {
"family": "Liang",
"given": "X. H."
}
},
{
"name": {
"family": "Liao",
"given": "J. Y."
}
},
{
"name": {
"family": "Liu",
"given": "H. W."
}
},
{
"name": {
"family": "Liu",
"given": "X. J."
}
},
{
"name": {
"family": "Lu",
"given": "X. F."
}
},
{
"name": {
"family": "Luo",
"given": "Q."
},
"orcid": "0000-0003-1853-7810"
},
{
"name": {
"family": "Luo",
"given": "T."
}
},
{
"name": {
"family": "Meng",
"given": "B."
}
},
{
"name": {
"family": "Nang",
"given": "Y."
}
},
{
"name": {
"family": "Nie",
"given": "J. Y."
}
},
{
"name": {
"family": "Ou",
"given": "G."
}
},
{
"name": {
"family": "Sai",
"given": "N."
}
},
{
"name": {
"family": "Shang",
"given": "R. C."
}
},
{
"name": {
"family": "Song",
"given": "X. Y."
}
},
{
"name": {
"family": "Sun",
"given": "L."
}
},
{
"name": {
"family": "Tan",
"given": "Y."
}
},
{
"name": {
"family": "Wang",
"given": "W. S."
}
},
{
"name": {
"family": "Wang",
"given": "Y. D."
}
},
{
"name": {
"family": "Wang",
"given": "Y. S."
}
},
{
"name": {
"family": "Wen",
"given": "X. Y."
}
},
{
"name": {
"family": "Wu",
"given": "B. B."
}
},
{
"name": {
"family": "Wu",
"given": "B. Y."
}
},
{
"name": {
"family": "Wu",
"given": "M."
}
},
{
"name": {
"family": "Xiao",
"given": "G. C."
}
},
{
"name": {
"family": "Xiao",
"given": "S."
}
},
{
"name": {
"family": "Xiong",
"given": "S. L."
}
},
{
"name": {
"family": "Yang",
"given": "S."
}
},
{
"name": {
"family": "Yang",
"given": "Y. J."
}
},
{
"name": {
"family": "Yi",
"given": "Q. B."
}
},
{
"name": {
"family": "Yin",
"given": "Q. Q."
},
"orcid": "0000-0001-7580-1513"
},
{
"name": {
"family": "You",
"given": "Y."
}
},
{
"name": {
"family": "Zhang",
"given": "F."
}
},
{
"name": {
"family": "Zhang",
"given": "H. M."
}
},
{
"name": {
"family": "Zhang",
"given": "J."
}
},
{
"name": {
"family": "Zhang",
"given": "W. C."
}
},
{
"name": {
"family": "Zhang",
"given": "W."
}
},
{
"name": {
"family": "Zhang",
"given": "Y. F."
}
},
{
"name": {
"family": "Zhao",
"given": "H. S."
}
},
{
"name": {
"family": "Zhao",
"given": "X. F."
}
},
{
"name": {
"family": "Zhou",
"given": "D. K."
}
}
]
},
"title": "A Variable Ionized Disk Wind in the Black Hole Candidate EXO 1846\u2013031",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "High energy astrophysics; X-ray transient sources; Accretion",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2020 July 30; revised 2020 October 25; accepted 2020 October 26; published 2020 December 29. \n\nWe are grateful to Timothy R. Kallman for help with xstar. We thank the anonymous referee for the helpful comments. This work made use of the data from the Insight-HXMT mission, a project funded by China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). The Insight-HXMT team gratefully acknowledges the support from the National Program on Key Research and Development Project (grant No. 2016YFA0400800) from the Minister of Science and Technology of China (MOST) and the Strategic Priority Research Program of the Chinese Academy of Sciences (grant No. XDB23040400). The authors thank the support from the National Natural Science Foundation of China under grant Nos. 11673023, 11733009, 11603037, 11973052, U1838201, U1838115, U1938103, and U1838202. Y.W. and L.Z. acknowledge support from the Royal Society Newton Funds. D.A. acknowledges support from the Royal Society. J.M. acknowledges the support from STFC (UK) through the University of Strathclyde UK APAP network grant ST/R000743/1. J.A.G. acknowledges support from NASA grant 80NSSC20K1238 and from the Alexander von Humboldt Foundation. Additionally, this work has made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nSoftware: XSPEC (v12.11.1; Arnaud 1996), NuSTARDAS (v2.0.0), HXMTDAS (v2.02; Zhang et al. 2020).\n\nPublished - Wang_2021_ApJ_906_11.pdf
Accepted Version - 2010.14662.pdf
",
"abstract": "After 34 yr, the black hole candidate EXO 1846\u2013031 went into outburst again in 2019. We investigate its spectral properties in the hard intermediate and the soft states with NuSTAR and Insight-HXMT. A reflection component has been detected in the two spectral states but possibly originating from different illumination spectra: in the intermediate state, the illuminating source is attributed to a hard coronal component, which has been commonly observed in other X-ray binaries, whereas in the soft state, the reflection is probably produced by disk self-irradiation. Both cases support EXO 1846\u2013031 as a low-inclination system of ~40\u00b0. An absorption line is clearly detected at ~7.2 keV in the hard intermediate state, corresponding to a highly ionized disk wind (log} \u03be > 6.1) with a velocity of up to 0.06c. Meanwhile, quasi-simultaneous radio emissions have been detected before and after the X-rays, implying the coexistence of disk winds and jets in this system. If only the high-flux segment of the NuSTAR observation is considered, the observed wind appears to be magnetically driven. The absorption line disappeared in the soft state and a narrow emission line appeared at ~6.7 keV on top of the reflection component, which may be evidence for disk winds, but data with higher spectral resolution are required to examine this.",
"date": "2021-01-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "906",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 11",
"id_number": "CaltechAUTHORS:20210112-151231714",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210112-151231714",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "China National Space Administration"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "XDB23040400"
},
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400800"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11673023"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11733009"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11603037"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11973052"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1838201"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1838115"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1938103"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1838202"
},
{
"agency": "Royal Society"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/R000743/1"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K1238"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/abc55e",
"primary_object": {
"basename": "Wang_2021_ApJ_906_11.pdf",
"url": "https://authors.library.caltech.edu/records/c4tzy-2eg85/files/Wang_2021_ApJ_906_11.pdf"
},
"related_objects": [
{
"basename": "2010.14662.pdf",
"url": "https://authors.library.caltech.edu/records/c4tzy-2eg85/files/2010.14662.pdf"
}
],
"pub_year": "2021",
"author_list": "Wang, Yanan; Ji, Long; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3x93f-26437",
"eprint_id": 106909,
"eprint_status": "archive",
"datestamp": "2023-08-20 01:13:29",
"lastmod": "2026-03-28 23:38:31",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Gurnett-Don-A",
"name": {
"family": "Gurnett",
"given": "D. A."
},
"orcid": "0000-0003-2403-0282"
},
{
"id": "Kurth-William-S",
"name": {
"family": "Kurth",
"given": "W. S."
},
"orcid": "0000-0002-5471-6202"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "B."
}
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "N."
}
},
{
"id": "Krimigis-Stamatios-M",
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Decker-R-B",
"name": {
"family": "Decker",
"given": "R. B."
}
},
{
"id": "Ness-N-F",
"name": {
"family": "Ness",
"given": "N. F."
}
},
{
"id": "Burlaga-Leonard-F",
"name": {
"family": "Burlaga",
"given": "L. F."
},
"orcid": "0000-0002-5569-1553"
}
]
},
"title": "A Foreshock Model for Interstellar Shocks of Solar Origin: Voyager 1 and 2 Observations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Interstellar medium",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2020 August 31; revised 2020 October 19; accepted 2020 October 19; published 2020 December 3. \n\nThe research at the University of Iowa was supported by NASA through Contract 1622510 with the Jet Propulsion Laboratory. The research at Caltech was supported by NASA award NNN12AA01C, and the research at the Johns Hopkins Applied Physics Laboratory was supported by the Voyager Interstellar Mission under NASA contract NNN06AA01C. The research at Goddard Spaceflight Center was supported by NASA contract 80GSFC19C0012. The Voyager PWS data are regularly archived with the Planetary Data System at https://pds.nasa.gov.\n\nPublished - Gurnett_2021_AJ_161_11.pdf
",
"abstract": "The Voyager 1 (V1) and Voyager 2 (V2) spacecraft were launched in 1977 on a mission to explore the outer planets and reach the heliopause, the boundary between the hot solar plasma and the relatively cool interstellar plasma. V1 reached the heliopause on 2012 August 25, at 121.6 au, and V2 reached the heliopause on 2018 November 5, at 119.0 au. One of their remarkable discoveries was the detection of shocks propagating into the interstellar plasma from energetic solar events. These shocks are typically preceded by electron plasma oscillations excited by electron beams streaming along interstellar magnetic field lines ahead of the shocks. The frequencies of the plasma oscillations have now provided radial electron density profiles in the outer heliosphere and in the interstellar medium to radial distances of more than 145 au. The oscillations are typically preceded by bursts of high-energy ~5\u2013100 MeV electrons. These electron bursts are interpreted as being due to the reflection (and acceleration) of cosmic-ray electrons by the shock at the time the shock first contacts the magnetic field line that passes through the spacecraft. Relative timing between the cosmic rays reflected by the shock and the onset of the plasma oscillations allow us, for the first time, to estimate the energy, ~20\u2013100 eV, of the electron beams responsible for the plasma oscillations. These observations are combined into a self-consistent model called the foreshock model that describes the interaction of shocks of solar origin with the interstellar plasma.",
"date": "2021-01",
"date_type": "published",
"publication": "Astronomical Journal",
"volume": "161",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 11",
"id_number": "CaltechAUTHORS:20201204-110355753",
"issn": "1538-3881",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201204-110355753",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "JPL",
"grant_number": "1622510"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80GSFC19C0012"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-3881/abc337",
"primary_object": {
"basename": "Gurnett_2021_AJ_161_11.pdf",
"url": "https://authors.library.caltech.edu/records/3x93f-26437/files/Gurnett_2021_AJ_161_11.pdf"
},
"pub_year": "2021",
"author_list": "Gurnett, D. A.; Kurth, W. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/p3k1t-fh972",
"eprint_id": 107966,
"eprint_status": "archive",
"datestamp": "2023-08-20 01:17:12",
"lastmod": "2026-03-29 00:21:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kantzas-Dimitrios",
"name": {
"family": "Kantzas",
"given": "D."
},
"orcid": "0000-0002-7364-606X"
},
{
"id": "Markoff-Sera",
"name": {
"family": "Markoff",
"given": "S."
},
"orcid": "0000-0001-9564-0876"
},
{
"id": "Beuchert-T",
"name": {
"family": "Beuchert",
"given": "T."
}
},
{
"id": "Lucchini-Matteo",
"name": {
"family": "Lucchini",
"given": "M."
},
"orcid": "0000-0002-2235-3347"
},
{
"id": "Chhotray-A",
"name": {
"family": "Chhotray",
"given": "A."
}
},
{
"id": "Ceccobello-Chiara",
"name": {
"family": "Ceccobello",
"given": "C."
},
"orcid": "0000-0002-4767-9925"
},
{
"id": "Tetarenko-Alexandra-J",
"name": {
"family": "Tetarenko",
"given": "A. J."
},
"orcid": "0000-0003-3906-4354"
},
{
"id": "Miller-Jones-James-C-A",
"name": {
"family": "Miller-Jones",
"given": "J. C. A."
},
"orcid": "0000-0003-3124-2814"
},
{
"id": "Bremer-Malcolm-N",
"name": {
"family": "Bremer",
"given": "M."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Grinberg-Victoria",
"name": {
"family": "Grinberg",
"given": "V."
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Uttley-Phil",
"name": {
"family": "Uttley",
"given": "P."
},
"orcid": "0000-0001-9355-961X"
},
{
"id": "Wilms-J\u00f6rn",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "A new lepto-hadronic model applied to the first simultaneous multiwavelength data set for Cygnus X\u20131",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "acceleration of particles \u2013 radiation mechanisms: non-thermal \u2013 X-rays: individual: Cyg X\u20131",
"note": "\u00a9 2020 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 October 20. Received 2020 October 16; in original form 2020 March 3. Published: 29 October 2020. \n\nWe would like to thank the reviewer for the very helpful comments on improving the original manuscript. DK would like to thank Maria Petropoulou for fruitful discussions, and Ping Zhou and Thomas Russell for useful comments on the manuscript. DK, SM, ML, and AC were supported by the Netherlands Organisation for Scientific Research (NWO) VICI grant (no. 639.043.513). VG is supported through the Margarete von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. JCAM-J is the recipient of an Australian Research Council Future Fellowship (FT140101082), funded by the Australian government. This work is based on observations carried out under the project number W15BQ with the IRAM NOEMA Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). This research made use of ASTROPY (http://www.astropy.org) a community-developed core PYTHON package for Astronomy (Astropy Collaboration et al. 2013; Price-Whelan et al. 2018), MATPLOTLIB (Hunter 2007), NUMPY (Oliphant 2006), SCIPY (Virtanen et al. 2020), ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.unierlangen.de/isis/), and the CTA instrument response functions provided by the CTA Consortium and Observatory, see http://www.cta-observatory.org/science/cta-performance/ (version prod3b-v2) for more details. \n\nData Availability: The data underlying this article are available in Zenodo, at https://dx.doi.org/10.5281/zenodo.4126910.\n\nPublished - staa3349.pdf
Accepted Version - 2010.08501.pdf
",
"abstract": "Cygnus X\u20131 is the first Galactic source confirmed to host an accreting black hole. It has been detected across the entire electromagnetic spectrum from radio to GeV gamma-rays. The source's radio through mid-infrared radiation is thought to originate from the relativistic jets. The observed high degree of linear polarization in the MeV X-rays suggests that the relativistic jets dominate in this regime as well, whereas a hot accretion flow dominates the soft X-ray band. The origin of the GeV non-thermal emission is still debated, with both leptonic and hadronic scenarios deemed to be viable. In this work, we present results from a new semi-analytical, multizone jet model applied to the broad-band spectral energy distribution of Cygnus X\u20131 for both leptonic and hadronic scenarios. We try to break this degeneracy by fitting the first-ever high-quality, simultaneous multiwavelength data set obtained from the CHOCBOX campaign (Cygnus X\u20131 Hard state Observations of a Complete Binary Orbit in X-rays). Our model parametrizes dynamical properties, such as the jet velocity profile, the magnetic field, and the energy density. Moreover, the model combines these dynamical properties with a self-consistent radiative transfer calculation including secondary cascades, both of leptonic and hadronic origin. We conclude that sensitive TeV gamma-ray telescopes like Cherenkov Telescope Array (CTA) will definitively answer the question of whether hadronic processes occur inside the relativistic jets of Cygnus X\u20131.",
"date": "2021-01",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "500",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2112-2126",
"id_number": "CaltechAUTHORS:20210209-120605988",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210209-120605988",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "639.043.513"
},
{
"agency": "European Social Fund"
},
{
"agency": "Ministry of Science, Research and the Arts (Baden-W\u00fcrttemberg)"
},
{
"agency": "Australian Research Council",
"grant_number": "FT140101082"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa3349",
"primary_object": {
"basename": "2010.08501.pdf",
"url": "https://authors.library.caltech.edu/records/p3k1t-fh972/files/2010.08501.pdf"
},
"related_objects": [
{
"basename": "staa3349.pdf",
"url": "https://authors.library.caltech.edu/records/p3k1t-fh972/files/staa3349.pdf"
}
],
"pub_year": "2021",
"author_list": "Kantzas, D.; Markoff, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nsv0h-deq48",
"eprint_id": 107274,
"eprint_status": "archive",
"datestamp": "2023-08-22 08:04:28",
"lastmod": "2026-03-28 22:44:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Dialynas-Konstantinos",
"name": {
"family": "Dialynas",
"given": "Konstantinos"
},
"orcid": "0000-0002-5231-7929"
},
{
"id": "Galli-Andre",
"name": {
"family": "Galli",
"given": "Andre"
},
"orcid": "0000-0003-2425-3793"
},
{
"id": "Dayeh-Maher-A",
"name": {
"family": "Dayeh",
"given": "Maher A."
},
"orcid": "0000-0001-9323-1200"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "Alan C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Decker-Robert-B",
"name": {
"family": "Decker",
"given": "Robert B."
},
"orcid": "0000-0002-0655-9863"
},
{
"id": "Fuselier-Stephen-A",
"name": {
"family": "Fuselier",
"given": "Stephen A."
},
"orcid": "0000-0003-4101-7901"
},
{
"id": "Gkioulidou-Matina",
"name": {
"family": "Gkioulidou",
"given": "Matina"
},
"orcid": "0000-0001-9979-2164"
},
{
"id": "Roussos-Elias",
"name": {
"family": "Roussos",
"given": "Elias"
},
"orcid": "0000-0002-5699-0678"
},
{
"id": "Krimigis-Stamatios-M",
"name": {
"family": "Krimigis",
"given": "Stamatios M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Mitchell-Donald-G",
"name": {
"family": "Mitchell",
"given": "Donald G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Richardson-John-D",
"name": {
"family": "Richardson",
"given": "John D."
},
"orcid": "0000-0003-4041-7540"
},
{
"id": "Opher-Merav",
"name": {
"family": "Opher",
"given": "Merav"
},
"orcid": "0000-0002-8767-8273"
}
]
},
"title": "Combined \u223c10 eV to \u223c344 MeV Particle Spectra and Pressures in the Heliosheath along the Voyager 2 Trajectory",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliosphere; Heliopause; Heliosheath; Termination shock; Interstellar medium; Interstellar magnetic fields",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2020 October 19; revised 2020 November 13; accepted 2020 November 16; published 2020 December 21. \n\nThis work was supported by the NASA Drive Science Centers initiative, under contract 80NSSC20K0603-18-DRIVE18_2-0029 in BU SHIELD DRIVE Science Center (http://sites.bu.edu/shield-drive/). The authors are grateful to all Cassini/MIMI, Voyager/LECP/PLS/CRS, and IBEX team members for useful discussions that made this work possible. The work at JHU/APL was supported also by NASA under contracts NAS5 97271, NNX07AJ69G, and NNN06AA01C and by subcontract at the Office for Space Research and Technology. The work at Caltech was supported by NASA award NNN12AA01C. J.D.R. was supported by NASA contract 959203 from JPL to MIT and NASA HGI 80NSSC19K0260.\n\nPublished - Dialynas_2020_ApJL_905_L24.pdf
",
"abstract": "We report a unique combination of ~10 eV to ~344 MeV in situ ion measurements from the Plasma Science (PLS), Low Energy Charged Particle (LECP), and Cosmic Ray Subsystem (CRS) experiments on the Voyager 2 (V2) spacecraft, and remotely sensed ~110 eV to ~55 keV energetic neutral atom (ENA) measurements from the Interstellar Boundary Explorer (IBEX) mission and Ion and Neutral Camera (INCA) on the Cassini mission. This combination is done over the time period from 2009 to the end of 2016, along the V2 trajectory, toward assessing the properties of the ion energy spectra inside the heliosheath. The combined energy spectra exhibit a series of softening and hardening breaks, providing important insights on the various ion acceleration processes inside the heliosheath. Ions in the <6 keV energy range dominate the total pressure distribution inside the heliosheath but the ion distributions at higher energies (>5.2 keV) provide a significant contribution to the total pressure. With the assumption that all ENAs (~110 eV to 55 keV) are created by charge-exchange interactions inside the heliosheath, we estimate that the magnetic field upstream at the heliopause required to balance the pressure from the heliosheath in the direction of V2 is ~0.67 nT. This number is consistent with the measured magnetic field at V2 from 2018 November, when the spacecraft entered interstellar space.",
"date": "2020-12-20",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "905",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L24",
"id_number": "CaltechAUTHORS:20201224-085807017",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201224-085807017",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC20K0603-18-DRIVE18_2-0029"
},
{
"agency": "NASA",
"grant_number": "NAS5 97271"
},
{
"agency": "NASA",
"grant_number": "NNX07AJ69G"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "NASA",
"grant_number": "959203"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0260"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/abcaaa",
"primary_object": {
"basename": "Dialynas_2020_ApJL_905_L24.pdf",
"url": "https://authors.library.caltech.edu/records/nsv0h-deq48/files/Dialynas_2020_ApJL_905_L24.pdf"
},
"pub_year": "2020",
"author_list": "Dialynas, Konstantinos; Galli, Andre; et al."
},
{
"id": "https://authors.library.caltech.edu/records/brge6-4m923",
"eprint_id": 107102,
"eprint_status": "archive",
"datestamp": "2023-08-22 07:59:55",
"lastmod": "2026-03-29 17:43:15",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hill-Matthew-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Kollmann",
"given": "P."
},
"orcid": "0000-0002-4274-9760"
},
{
"name": {
"family": "Brown",
"given": "L. E."
},
"orcid": "0000-0002-9171-0862"
},
{
"name": {
"family": "Decker",
"given": "R. B."
},
"orcid": "0000-0002-0655-9863"
},
{
"name": {
"family": "McNutt",
"given": "R. L."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"name": {
"family": "Andrews",
"given": "G. B."
}
},
{
"name": {
"family": "Bagenal",
"given": "F."
},
"orcid": "0000-0002-3963-1614"
},
{
"name": {
"family": "Clark",
"given": "G."
},
"orcid": "0000-0002-5264-7194"
},
{
"name": {
"family": "Elliott",
"given": "H. A."
},
"orcid": "0000-0003-2297-3922"
},
{
"name": {
"family": "Jaskulek",
"given": "S. E."
}
},
{
"name": {
"family": "Kusterer",
"given": "M. B."
}
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Lisse",
"given": "C. M."
},
"orcid": "0000-0002-9548-1526"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Nelson",
"given": "K. S."
},
"orcid": "0000-0003-3807-4518"
},
{
"name": {
"family": "Richardson",
"given": "J. D."
},
"orcid": "0000-0003-4041-7540"
},
{
"name": {
"family": "Romeo",
"given": "G."
}
},
{
"name": {
"family": "Salazar",
"given": "N. A."
}
},
{
"name": {
"family": "Vandegriff",
"given": "J. D."
},
"orcid": "0000-0002-0781-1565"
},
{
"name": {
"family": "Bernardoni",
"given": "E. A."
}
},
{
"name": {
"family": "Gladstone",
"given": "G. R."
},
"orcid": "0000-0003-0060-072X"
},
{
"name": {
"family": "Horanyi",
"given": "M."
},
"orcid": "0000-0002-5920-9226"
},
{
"name": {
"family": "Linscott",
"given": "I. R."
}
},
{
"name": {
"family": "Singer",
"given": "K. N."
},
"orcid": "0000-0003-3045-8445"
},
{
"name": {
"family": "Steffl",
"given": "A. J."
},
"orcid": "0000-0002-5358-392X"
},
{
"name": {
"family": "Summers",
"given": "M. E."
},
"orcid": "0000-0001-5986-8902"
},
{
"name": {
"family": "Throop",
"given": "H. B."
},
"orcid": "0000-0002-1988-223X"
},
{
"name": {
"family": "Young",
"given": "L. A."
},
"orcid": "0000-0002-7547-3967"
},
{
"name": {
"family": "Olkin",
"given": "C. B."
},
"orcid": "0000-0002-5846-716X"
},
{
"name": {
"family": "Parker",
"given": "J. Wm."
},
"orcid": "0000-0002-3672-0603"
},
{
"name": {
"family": "Spencer",
"given": "J. R."
},
"orcid": "0000-0003-4452-8109"
},
{
"name": {
"family": "Stern",
"given": "S. A."
},
"orcid": "0000-0001-5018-7537"
},
{
"name": {
"family": "Verbiscer",
"given": "A. J."
},
"orcid": "0000-0002-3323-9304"
},
{
"name": {
"family": "Weaver",
"given": "H. A."
},
"orcid": "0000-0003-0951-7762"
}
]
},
"title": "Influence of Solar Disturbances on Galactic Cosmic Rays in the Solar Wind, Heliosheath, and Local Interstellar Medium: Advanced Composition Explorer, New Horizons, and Voyager Observations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Interstellar magnetic fields; Galactic cosmic rays; Solar wind; Solar wind termination; Heliopause; Heliosheath; Solar energetic particles; Cosmic rays; Forbush effect; Interplanetary shocks; Solar cycle; Cosmic ray detectors",
"note": "\u00a9 2020. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2019 August 5; revised 2020 August 25; accepted 2020 August 27; published 2020 December 14. \n\nThe NH work was supported by NASA NH funding through contract NAS5-97271/Task Order 30 and NASA Voyager Interstellar Mission NNN06AA01C. NH/PEPSSI data are publicly available through NASA's planetary data archive (https://pds.nasa.gov). We thank the ACE SWEPAM instrument team and the ACE Science Center (http://www.srl.caltech.edu/ACE/ASC/level2/new/) for providing the solar wind data. We appreciate the efforts of the Voyager MAG team in providing V1 magnetic field measurements (https://omniweb.gsfc.nasa.gov). We acknowledge and thank the network of observers who provided the sunspot number measurements, courtesy of the Royal Observatory of Belgium, Brussels (http://www.sidc.be/silso/home). M.E.H. would like to acknowledge helpful conversations with members of the NASA DRIVE science center, Our Heliospheric Shield, NASA grant 18-DRIVE18_2-0029, 80NSSC20K0603, during the revision stage of this paper.\n\nPublished - Hill_2020_ApJ_905_69.pdf
",
"abstract": "We augment the heliospheric network of galactic cosmic ray (GCR) monitors using 2012\u20132017 penetrating radiation measurements from the New Horizons (NH) Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI), obtaining intensities of \u227375 MeV particles. The new, predominantly GCR observations provide critical links between the Sun and Voyager 2 and Voyager 1 (V2 and V1), in the heliosheath and local interstellar medium (LISM), respectively. We provide NH, Advanced Composition Explorer (ACE), V2, and V1 GCR observations, using them to track solar cycle variations and short-term Forbush decreases from the Sun to the LISM, and to examine the interaction that results in the surprising, previously reported V1 LISM anisotropy episodes. To investigate these episodes and the hitherto unexplained lagging of associated in situ shock features at V1, propagating disturbances seen at ACE, NH, and V2 were compared to V1. We conclude that the region where LISM magnetic field lines drape around the heliopause is likely critical for communicating solar disturbance signals upstream of the heliosheath to V1. We propose that the anisotropy-causing physical process that suppresses intensities at ~90\u00b0 pitch angles relies on GCRs escaping from a single compression in the draping region, not on GCRs trapped between two compressions. We also show that NH suprathermal and energetic particle data from PEPSSI are consistent with the interpretation that traveling shocks and corotating interaction region (CIR) remnants can be distinguished by the existence or lack of Forbush decreases, respectively, because turbulent magnetic fields at local shocks inhibit GCR transport while older CIR structures reaching the outer heliosphere do not.",
"date": "2020-12-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "905",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 69",
"id_number": "CaltechAUTHORS:20201215-141038410",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201215-141038410",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NAS5-97271"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "18-DRIVE18_2-0029"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0603"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abb408",
"primary_object": {
"basename": "Hill_2020_ApJ_905_69.pdf",
"url": "https://authors.library.caltech.edu/records/brge6-4m923/files/Hill_2020_ApJ_905_69.pdf"
},
"pub_year": "2020",
"author_list": "Hill, M. E.; Allen, R. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/271rm-5s795",
"eprint_id": 107093,
"eprint_status": "archive",
"datestamp": "2023-10-03 22:34:02",
"lastmod": "2026-03-29 18:25:04",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Madejski-G-M",
"name": {
"family": "Madejski",
"given": "G."
}
},
{
"id": "Comastri-Andrea",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Annuar-Adlyka",
"name": {
"family": "Annuar",
"given": "A."
},
"orcid": "0000-0003-0387-1429"
},
{
"id": "Ballantyne-David-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Boorman-Peter-G",
"name": {
"family": "Boorman",
"given": "P."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Brandt-W-Niel",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Kamraj-Nikita",
"name": {
"family": "Kamraj",
"given": "N."
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M. J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Marchesi-Stefano",
"name": {
"family": "Marchesi",
"given": "S."
},
"orcid": "0000-0001-5544-0749"
},
{
"id": "Marinucci-Andrea",
"name": {
"family": "Marinucci",
"given": "A."
},
"orcid": "0000-0002-2055-4946"
},
{
"id": "Masini-Alberto",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Matt-Giorgio",
"name": {
"family": "Matt",
"given": "G."
},
"orcid": "0000-0002-2152-0916"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Urry-C-Megan",
"name": {
"family": "Urry",
"given": "C. M."
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "NuSTAR Survey of Obscured Swift/BAT-selected Active Galactic Nuclei. II. Median High-energy Cutoff in Seyfert II Hard X-Ray Spectra",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; X-ray active galactic nuclei; Seyfert galaxies; High energy astrophysics; X-ray surveys",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2020 April 19; revised 2020 August 7; accepted 2020 August 25; published 2020 December 11. \n\nThe authors appreciate helpful suggestions from the anonymous referee, which helped to improve the clarity of the paper. \n\nM.B. acknowledges support from the YCAA Prize Postdoctoal Fellowship, the National Aeronautics and Space Administration (NASA) under the NASA Earth and Space Science Fellowship program (grant NNX14AQ07H), and support from the Black Hole Initiative at Harvard University, which is funded in part by the Gordon and Betty Moore Foundation (grant GBMF8273) and in part by the John Templeton Foundation. A.C. and G.M. acknowledge support from the ASI/INAF grant I/037/12/0 and the Caltech Kingsley fellowship program. A.A. acknowledges financial support from Ministry of Education Malaysia Fundamental Research Grant Scheme grant code FRGS/1/2019/STG02/UKM/02/7. P.B. acknowledges financial support from the STFC and the Czech Science Foundation project No. 19-05599Y. P.G. acknowledges support from the STFC and a UGC/UKIERI Thematic Partnership. \n\nWe have made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the Space Science Data Center (SSDC; ASI, Italy) and the California Institute of Technology (USA). Part of this work is based on archival data, software, or online services provided by the SSDC. This research has made use of the High Energy Astrophysics Science Archive Research Center Online Service, provided by the NASA/Goddard Space Flight Center and NASA's Astrophysics Data System. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift. - \n\nSoftware: Astropy (Astropy Collaboration et al. 2013, 2018), ASURV (Feigelson et al. 2014), Matplotlib (Hunter 2007), Xspec (Arnaud 1996).\n\nPublished - Balokovic_2020_ApJ_905_41.pdf
Submitted - 2011-06583.pdf
",
"abstract": "Broadband X-ray spectroscopy of the X-ray emission produced in the coronae of active galactic nuclei (AGNs) can provide important insights into the physical conditions very close to their central supermassive black holes. The temperature of the Comptonizing plasma that forms the corona is manifested through a high-energy cutoff that has been difficult to directly constrain even in the brightest AGN because it requires high-quality data at energies above 10 keV. In this paper we present a large collection of coronal cutoff constraints for obscured AGNs based on a sample of 130 AGNs selected in the hard X-ray band with Swift/BAT and observed nearly simultaneously with NuSTAR and Swift/XRT. We find that under a reasonable set of assumptions regarding partial constraints the median cutoff is well constrained to 290 \u00b1 20 keV, where the uncertainty is statistical and given at the 68% confidence level. We investigate the sensitivity of this result to our assumptions and find that consideration of various known systematic uncertainties robustly places the median cutoff between 240 and 340 keV. The central 68% of the intrinsic cutoff distribution is found to be between about 140 and 500 keV, with estimated uncertainties of 20 and 100 keV, respectively. In comparison with the literature, we find no clear evidence that the cutoffs in obscured and unobscured AGNs are substantially different. Our analysis highlights the importance of carefully considering partial and potentially degenerate constraints on the coronal high-energy cutoff in AGNs.",
"date": "2020-12-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "905",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 41",
"id_number": "CaltechAUTHORS:20201215-141036856",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201215-141036856",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Yale Center for Astronomy and Astrophysics"
},
{
"agency": "Gordon and Betty Moore Foundation",
"grant_number": "GBMF8273"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Lewis A. Kingsley Fellowship"
},
{
"agency": "Ministry of Education (Malaysia)",
"grant_number": "FRGS/1/2019/STG02/UKM/02/7"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Czech Science Foundation",
"grant_number": "19-05599Y"
},
{
"agency": "UK India Education Research Initiative (UKIERI)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/abc342",
"primary_object": {
"basename": "2011-06583.pdf",
"url": "https://authors.library.caltech.edu/records/271rm-5s795/files/2011-06583.pdf"
},
"related_objects": [
{
"basename": "Balokovic_2020_ApJ_905_41.pdf",
"url": "https://authors.library.caltech.edu/records/271rm-5s795/files/Balokovic_2020_ApJ_905_41.pdf"
}
],
"pub_year": "2020",
"author_list": "Balokovi\u0107, M.; Harrison, F. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jmr6f-p8r04",
"eprint_id": 107000,
"eprint_status": "archive",
"datestamp": "2023-08-20 00:09:21",
"lastmod": "2026-03-30 13:38:21",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Shaw-Aarran-W",
"name": {
"family": "Shaw",
"given": "A. W."
},
"orcid": "0000-0002-8808-520X"
},
{
"id": "Heinke-Craig-O",
"name": {
"family": "Heinke",
"given": "C. O."
},
"orcid": "0000-0003-3944-6109"
},
{
"id": "Mukai-K",
"name": {
"family": "Mukai",
"given": "K."
}
},
{
"id": "Tomsick-John-A",
"name": {
"family": "Tomsick",
"given": "J. A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Doroshenko-Victor",
"name": {
"family": "Doroshenko",
"given": "V."
},
"orcid": "0000-0001-8162-1105"
},
{
"id": "Suleimanov-Valery-F",
"name": {
"family": "Suleimanov",
"given": "V. F."
},
"orcid": "0000-0003-3733-7267"
},
{
"id": "Buisson-D-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
}
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Hare-J",
"name": {
"family": "Hare",
"given": "J."
}
},
{
"id": "Jiang-J",
"name": {
"family": "Jiang",
"given": "J."
}
},
{
"id": "Ludlam-Renee-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Rana-V-R",
"name": {
"family": "Rana",
"given": "V."
},
"orcid": "0000-0003-1703-8796"
},
{
"id": "Sivakoff-Gregory-R",
"name": {
"family": "Sivakoff",
"given": "G. R."
},
"orcid": "0000-0001-6682-916X"
}
]
},
"title": "Measuring the masses of magnetic white dwarfs: a NuSTAR legacy survey",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, novae, cataclysmic variables, white dwarfs",
"note": "\u00a9 2020 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 August 19. Received 2020 August 14; in original form 2020 June 26. \n\nWe would like to thank the anonymous referee for useful comments that helped improve the manuscript. We also thank Fiona Harrison and the NuSTAR team for approving the mCV Legacy programme. AWS would like to thank Rich Plotkin for useful discussions regarding some of the results in this work. AWS would also like to thank Phil Uttley, Abigail Stevens, and Peter Bult for advice regarding timing analysis. COH acknowledges support from NSERC Discovery grant RGPIN-2016-04602, and a Discovery Accelerator Supplement. VD and VFS thank the Russian Science Foundation (grant 19-12-00423) for financial support. VFS also thanks Deutsche Forschungsgemeinschaft for financial support (grant WE 1312/51-1). DJKB acknowledges support from the Royal Society. BWG acknowledges support under NASA contract No. NNG08FD60C. JH acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the USRA through a contract with NASA. JJ acknowledges support by the Tsinghua Shuimu Fellowship and the Tsinghua Astrophysics Outstanding Fellowship. RML acknowledges the support of NASA through Hubble Fellowship Program grant HST-HF2-51440.001. GRS acknowledges support from an NSERC Discovery grant (RGPIN-2016-06569). \n\nThis work has used data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has used the NuSTARDAS jointly developed by the ASI Science Data Center (Italy) and the California Institute of Technology (USA). This research has used data and/or software provided by the High Energy Astrophysics Science Archive Research Center, which is a service of the Astrophysics Science Division at NASA/GSFC. \n\nDATA AVAILABILITY STATEMENT. The data underlying this article are publicly available in the NuSTAR Master Catalog (NUMASTER) at https://heasarc.gsfc.nasa.gov/W3Browse/nustar/numaster.html. The Observation ID for each target is listed in Table 1.\n\nPublished - staa2592.pdf
Accepted Version - 2008.09684.pdf
",
"abstract": "The hard X-ray spectrum of magnetic cataclysmic variables can be modelled to provide a measurement of white dwarf mass. This method is complementary to radial velocity measurements, which depend on the (typically rather uncertain) binary inclination. Here, we present results from a Legacy Survey of 19 magnetic cataclysmic variables with NuSTAR. We fit accretion column models to their 20\u201378\u2009keV spectra and derive the white dwarf masses, finding a weighted average M\u00af_(WD) = 0.77\u00b10.02\u2009M_\u2299, with a standard deviation \u03c3 = 0.10\u2009M_\u2299, when we include the masses derived from previous NuSTAR observations of seven additional magnetic cataclysmic variables. We find that the mass distribution of accreting magnetic white dwarfs is consistent with that of white dwarfs in non-magnetic cataclysmic variables. Both peak at a higher mass than the distributions of isolated white dwarfs and post-common-envelope binaries. We speculate as to why this might be the case, proposing that consequential angular momentum losses may play a role in accreting magnetic white dwarfs and/or that our knowledge of how the white dwarf mass changes over accretion\u2013nova cycles may also be incomplete.",
"date": "2020-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "498",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3457-3469",
"id_number": "CaltechAUTHORS:20201209-153311091",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201209-153311091",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)",
"grant_number": "RGPIN-2016-04602"
},
{
"agency": "Russian Science Foundation",
"grant_number": "19-12-00423"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "WE 1312/51-1"
},
{
"agency": "Royal Society"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "Tsinghua University"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)",
"grant_number": "RGPIN-2016-06569"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa2592",
"primary_object": {
"basename": "2008.09684.pdf",
"url": "https://authors.library.caltech.edu/records/jmr6f-p8r04/files/2008.09684.pdf"
},
"related_objects": [
{
"basename": "staa2592.pdf",
"url": "https://authors.library.caltech.edu/records/jmr6f-p8r04/files/staa2592.pdf"
}
],
"pub_year": "2020",
"author_list": "Shaw, A. W.; Heinke, C. O.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mca73-7bs20",
"eprint_id": 105914,
"eprint_status": "archive",
"datestamp": "2023-08-22 06:55:28",
"lastmod": "2026-03-30 06:36:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mitchell-J-G",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "de-Nolfo-G-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Hill-M-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "McComas-D-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Schwadron-N-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Bale-S-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Case-A-W",
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Joyce-C-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Kasper-J-C",
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "MacDowall-R-J",
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Mitchell-D-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Pulupa-M",
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"id": "Richardson-I-G",
"name": {
"family": "Richardson",
"given": "I. G."
},
"orcid": "0000-0002-3855-3634"
},
{
"id": "Stevens-M-L",
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"id": "Szalay-J-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
}
]
},
"title": "Small Electron Events Observed by Parker Solar Probe/IS\u2299IS during Encounter 2",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar flares; Solar energetic particles; Solar particle emission; Radio bursts; Solar physics",
"note": "\u00a9 2020. The Author(s). Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2020 May 20; revised 2020 July 24; accepted 2020 August 24; published 2020 October 8. \n\nWe wish to acknowledge the support of NASA's Parker Solar Probe grant NNN06AA01C. We thank the Parker Solar Probe IS\u2299IS, FIELDS, and SWEAP teams, including the engineers, technicians, administrators, and scientists, who developed the instruments used in this study. The IS\u2299IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - Mitchell_2020_ApJ_902_20.pdf
",
"abstract": "The current understanding of the characteristics of solar and inner heliospheric electron events is inferred almost entirely from observations made by spacecraft located at 1 astronomical unit (au). Previous observations within 1 au of the Sun, by the Helios spacecraft at ~0.3\u20131 au, indicate the presence of electron events that are not detected at 1 au or may have merged during transport from the Sun. Parker Solar Probe's close proximity to the Sun at perihelion provides an opportunity to make the closest measurements yet of energetic electron events. We present an overview of measurements of electrons with energies between ~17 keV and ~1 MeV made by the Parker Solar Probe Integrated Science Investigation of the Sun (IS\u2299IS) instrument suite during Encounter 2 (2019 March 31\u2013April 10 with perihelion of ~0.17 au), including several small electron events. We examine these events in the context of the electromagnetic and solar wind environment measured by the FIELDS and SWEAP instruments on Parker Solar Probe. We find most of these electron enhancements to be associated with type III radio emissions that reach the local plasma frequency and one enhancement that appears to be primarily associated with abrupt changes in the local magnetic field. Together, these associations suggest that these are indeed the first measurements of energetic electron events within 0.2 au.",
"date": "2020-10-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "902",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 20",
"id_number": "CaltechAUTHORS:20201008-083809185",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201008-083809185",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4357/abb2a4",
"primary_object": {
"basename": "Mitchell_2020_ApJ_902_20.pdf",
"url": "https://authors.library.caltech.edu/records/mca73-7bs20/files/Mitchell_2020_ApJ_902_20.pdf"
},
"pub_year": "2020",
"author_list": "Mitchell, J. G.; de Nolfo, G. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9n434-39v78",
"eprint_id": 106199,
"eprint_status": "archive",
"datestamp": "2023-08-19 23:39:13",
"lastmod": "2026-03-28 23:36:33",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Staubert-R",
"name": {
"family": "Staubert",
"given": "R."
},
"orcid": "0000-0003-1498-1543"
},
{
"id": "Ducci-L",
"name": {
"family": "Ducci",
"given": "L."
}
},
{
"id": "Ji-L",
"name": {
"family": "Ji",
"given": "L."
}
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Rothschild-R-E",
"name": {
"family": "Rothschild",
"given": "R. E."
}
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "K."
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "Brumback-M-C",
"name": {
"family": "Brumback",
"given": "M."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Cyclotron line energy in Hercules X-1: stable after the decay",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: magnetic field / radiation mechanisms: general / scattering / pulsars: individual: Her X-1 / stars: neutron / X-rays: stars",
"note": "\u00a9 ESO 2020. \n\nReceived: 6 July 2020. Accepted: 14 August 2020. \n\nWe would like to acknowledge the dedication of all the people who have contributed to the great success of all relevant missions, in particular NuSTAR. We especially thank the \"schedulers\", foremost Karl Forster, for his efforts with respect to the non-standard scheduling of the observations of Her X-1. We acknowledge the historical contributions to the subject at hand by Dmitry Klochkov. We thank the anonymous referee for valuable comments.\n\nPublished - aa38855-20.pdf
",
"abstract": "We summarize the results of a dedicated effort made between 2012 and 2019 to follow the evolution of the cyclotron line in Her X-1 through repeated NuSTAR observations. The previously observed nearly 20-year-long decay of the cyclotron line energy has ended in 2012: from then on, the pulse-phase-averaged flux-corrected cyclotron line energy has remained stable and constant at an average value of E_(cyc) = (37.44\u2005\u00b1\u20050.07) keV (normalized to a flux level of 6.8 RXTE/ASM-cts s\u207b\u00b9). The flux dependence of E_(cyc) discovered in 2007 is now measured with high precision, giving a slope of (0.675\u2005\u00b1\u20050.075) keV/(ASM-cts s\u207b\u00b9), corresponding to an increase of 6.5% of E_(cyc) for an increase in flux by a factor of two. We also find that all line parameters as well as the continuum parameters show a correlation with X-ray flux. While a correlation between E_(cyc) and X-ray flux (both positive and negative) is now known for several accreting binaries with various suggestions for the underlying physics, the phenomenon of a long-term decay has so far only been seen in Her X-1 and Vela X-1, with far less convincing explanations.",
"date": "2020-10",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "642",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A196",
"id_number": "CaltechAUTHORS:20201021-160147836",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201021-160147836",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1051/0004-6361/202038855",
"primary_object": {
"basename": "aa38855-20.pdf",
"url": "https://authors.library.caltech.edu/records/9n434-39v78/files/aa38855-20.pdf"
},
"pub_year": "2020",
"author_list": "Staubert, R.; Ducci, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/p0mr3-esh29",
"eprint_id": 105751,
"eprint_status": "archive",
"datestamp": "2023-08-19 23:31:53",
"lastmod": "2026-03-29 21:53:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Richardson-J-D",
"name": {
"family": "Richardson",
"given": "John D."
},
"orcid": "0000-0003-4041-7540"
},
{
"id": "Belcher-J-W",
"name": {
"family": "Belcher",
"given": "John W."
}
},
{
"id": "Burlaga-L-F",
"name": {
"family": "Burlaga",
"given": "Leonard F."
},
"orcid": "0000-0002-5569-1553"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "Alan C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Decker-R-B",
"name": {
"family": "Decker",
"given": "Robert B."
}
},
{
"id": "Opher-M",
"name": {
"family": "Opher",
"given": "Merav"
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Edward C."
},
"orcid": "0000-0002-2010-5462"
}
]
},
"title": "Voyager 2 Observations Near the Heliopause",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2020 Institute of Physics. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nAccepted papers received: 10 August 2020; Published online: 30 September 2020. \n\nJDR was supported under NASA contract 959203 from the Jet Propulsion Laboratory to the Massachusetts Institute of Technology and NASA grant 80NSSC19K0260. RBD was supported by NASA contract NNN06AA01C. ECS and ACC were supported by NASA grant NNN12AA01C. ACC, RBD, MO, and JDR acknowledge support from NASA grant 18-DRIVE18_2-0029, Our Heliospheric Shield.\n\nPublished - Richardson_2020_J._Phys.__Conf._Ser._1620_012016.pdf
",
"abstract": "This paper discusses plasma characteristics in the heliosheath region before the heliopause (HP), at the HP, and in the very local interstellar medium (VLISM). The Voyager 2 (V2) HP was a sharp boundary where the radial plasma currents went to background levels. The radial flow speeds derived from 53-85 keV (V1) and 28-43 keV (V2) ion data decreased about 2 years (8 AU) before the HP at V1 and V2. A speed decrease was not observed by the V2 plasma instrument until 160 days (1.5 AU) before the HP crossing when V2 entered the plasma boundary layer where the plasma density and 28-43 keV ion intensity increased. We determine the HP orientation based on the plasma flow and magnetic field data and show these observations are consistent with models predicting a blunt HP. Variations are observed in the currents observed in the VLISM; roll data from this region clearly show the plasma instrument observes the interstellar plasma and may be consistent with larger than expected VLISM temperatures near the HP.",
"date": "2020-09-30",
"date_type": "published",
"publication": "Journal of Physics Conference Series",
"volume": "1620",
"publisher": "IOP",
"pagerange": "Art. No. 012016",
"id_number": "CaltechAUTHORS:20201002-094021793",
"issn": "1742-6588",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-094021793",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "959203"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0260"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "NASA",
"grant_number": "18-DRIVE18_2-0029"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1088/1742-6596/1620/1/012016",
"primary_object": {
"basename": "Richardson_2020_J._Phys.__Conf._Ser._1620_012016.pdf",
"url": "https://authors.library.caltech.edu/records/p0mr3-esh29/files/Richardson_2020_J._Phys.__Conf._Ser._1620_012016.pdf"
},
"pub_year": "2020",
"author_list": "Richardson, John D.; Belcher, John W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/rb9vc-rbe75",
"eprint_id": 102510,
"eprint_status": "archive",
"datestamp": "2023-08-22 06:22:43",
"lastmod": "2026-03-28 20:57:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Saade-M-L",
"name": {
"family": "Saade",
"given": "M. Lynne"
},
"orcid": "0000-0001-7163-7015"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Haiman-Z",
"name": {
"family": "Haiman",
"given": "Zolt\u00e1n"
},
"orcid": "0000-0003-3633-5403"
},
{
"id": "Djorgovski-S-G",
"name": {
"family": "Djorgovski",
"given": "S. G."
},
"orcid": "0000-0002-0603-3087"
},
{
"id": "D'Orazio-D-J",
"name": {
"family": "D'Orazio",
"given": "Daniel"
},
"orcid": "0000-0002-1271-6247"
},
{
"id": "Ford-K-E-S",
"name": {
"family": "Ford",
"given": "K. E. S."
}
},
{
"id": "Graham-M-J",
"name": {
"family": "Graham",
"given": "Matthew J."
},
"orcid": "0000-0002-3168-0139"
},
{
"id": "Jun-Hyunsung-David",
"name": {
"family": "Jun",
"given": "Hyunsung D."
},
"orcid": "0000-0003-1470-5901"
},
{
"id": "Kraft-R-P",
"name": {
"family": "Kraft",
"given": "Ralph P."
},
"orcid": "0000-0002-0765-0511"
},
{
"id": "McKernan-B",
"name": {
"family": "McKernan",
"given": "Barry"
},
"orcid": "0000-0002-9726-0508"
},
{
"id": "Vikhlinin-A",
"name": {
"family": "Vikhlinin",
"given": "Alexei"
},
"orcid": "0000-0001-8121-0234"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Chandra Observations of Candidate Subparsec Binary Supermassive Black Holes",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Quasars; Supermassive black holes; Active galactic nuclei; Active galaxies; X-ray active galactic nuclei",
"note": "\u00a9 2020 The American Astronomical Society.\n\nReceived 2020 February 18; revised 2020 July 22; accepted 2020 August 5; published 2020 September 11.\n\nWe thank the anonymous referee for a very thorough report, which has improved the paper. Support for this work was provided by the National Aeronautics and Space Administration (NASA) through Chandra Award Number 18700580 issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the NASA under contract NAS8-03060. The work of D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. Z.H. acknowledges support from NSF grant 1715661 and NASA grants 80NSSC19K0149 and NNX17AL82G. M.J.G. and S.G.D. were supported in part by NASA grant 16-ADAP16-0232 and NSF grants AST-1413600, AST-1518308, and AST-1749235. D.J.D. acknowledges funding from the Institute for Theory and Computation Fellowship. K.E.S.F. and B.M. were supported by NSF grant 1831412. H.D.J. was supported by the Basic Science Research Program through the National Research Foundation of Korea, funded by the Ministry of Education (NRF-2017R1A6A3A04005158).\n\nPublished - Saade_2020_ApJ_900_148.pdf
Submitted - 2001.08870.pdf
",
"abstract": "We present analysis of Chandra X-ray observations of seven quasars that were identified as candidate subparsec binary supermassive black hole (SMBH) systems in the Catalina Real-Time Transient Survey based on the apparent periodicity in their optical light curves. Simulations predict that close-separation accreting SMBH binaries will have different X-ray spectra than single accreting SMBHs, including harder or softer X-ray spectra, ripple-like profiles in the Fe K-\u03b1 line, and distinct peaks in the spectrum due to the separation of the accretion disk into a circumbinary disk and mini disks around each SMBH. We obtained Chandra observations to test these models and assess whether these quasars could contain binary SMBHs. We instead find that the quasar spectra are all well fit by simple absorbed power-law models, with the rest-frame 2\u201310 keV photon indices, \u0393, and the X-ray-to-optical power slopes, \u03b1_(OX), indistinguishable from those of the larger quasar population. This may indicate that these seven quasars are not truly subparsec binary SMBH systems, or it may simply reflect that our sample size was too small to robustly detect any differences. Alternatively, the X-ray spectral changes might only be evident at energies higher than probed by Chandra. Given the available models and current data, no firm conclusions are drawn. These observations will help motivate and direct further work on theoretical models of binary SMBH systems, such as modeling systems with thinner accretion disks and larger binary separations.",
"date": "2020-09-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "900",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 148",
"id_number": "CaltechAUTHORS:20200413-151905111",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200413-151905111",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Chandra",
"grant_number": "18700580"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NSF",
"grant_number": "AST-1715661"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0149"
},
{
"agency": "NASA",
"grant_number": "NNX17AL82G"
},
{
"agency": "NASA",
"grant_number": "16-ADAP16-0232"
},
{
"agency": "NSF",
"grant_number": "AST-1413600"
},
{
"agency": "NSF",
"grant_number": "AST-1518308"
},
{
"agency": "NSF",
"grant_number": "AST-1749235"
},
{
"agency": "Institute for Theory and Computation"
},
{
"agency": "NSF",
"grant_number": "AST-1831412"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2017R1A6A3A04005158"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/abad31",
"primary_object": {
"basename": "2001.08870.pdf",
"url": "https://authors.library.caltech.edu/records/rb9vc-rbe75/files/2001.08870.pdf"
},
"related_objects": [
{
"basename": "Saade_2020_ApJ_900_148.pdf",
"url": "https://authors.library.caltech.edu/records/rb9vc-rbe75/files/Saade_2020_ApJ_900_148.pdf"
}
],
"pub_year": "2020",
"author_list": "Saade, M. Lynne; Stern, Daniel; et al."
},
{
"id": "https://authors.library.caltech.edu/records/rs3y8-xzy67",
"eprint_id": 105385,
"eprint_status": "archive",
"datestamp": "2023-08-19 23:11:09",
"lastmod": "2026-03-29 17:36:26",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ballhausen-R",
"name": {
"family": "Ballhausen",
"given": "Ralf"
},
"orcid": "0000-0002-1118-8470"
},
{
"id": "Lorenz-Maximilian",
"name": {
"family": "Lorenz",
"given": "Maximilian"
},
"orcid": "0000-0001-6553-9590"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "Corrales-Lia",
"name": {
"family": "Corrales",
"given": "Lia"
},
"orcid": "0000-0002-5466-3817"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Bissinger-n\u00e9-K\u00fchnel-M",
"name": {
"family": "Bissinger n\u00e9 K\u00fchnel",
"given": "Matthias"
},
"orcid": "0000-0002-8709-8236"
},
{
"id": "Kretschmar-P",
"name": {
"family": "Kretschmar",
"given": "Peter"
},
"orcid": "0000-0001-9840-2048"
},
{
"id": "Kallman-Timothy-R",
"name": {
"family": "Kallman",
"given": "Timothy R."
},
"orcid": "0000-0002-5779-6906"
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Hell-Natalie",
"name": {
"family": "Hell",
"given": "Natalie"
},
"orcid": "0000-0003-3057-1536"
},
{
"id": "Psadaraki-I",
"name": {
"family": "Psadaraki",
"given": "Ioanna"
}
},
{
"id": "Rogantini-Daniele",
"name": {
"family": "Rogantini",
"given": "Daniele"
},
"orcid": "0000-0002-5359-9497"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "Dust and gas absorption in the high mass X-ray binary IGR J16318\u22124848",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-rays: binaries / dust, extinction / X-rays: individuals: IGR J16318-4848 / circumstellar matter",
"note": "\u00a9 ESO 2020. \n\nReceived 1 May 2020 / Accepted 2 July 2020. \n\nWe thank the anonymous referee for constructive comments that helped to improve the manuscript. We thank Jakob Stierhof, Daniel Stern, and Stefan Licklederer for extensive and fruitful discussions. R.B. acknowledges partial funding by the Bundesministerium f\u00fcr Wirtschaft under Deutsches Zentrum f\u00fcr Luft- und Raumfahrt contract 50 OR 1410. V.G. is supported through the Margarete von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. Work at LLNL is conducted under the auspices of the US DOE under Contract DE-AC52-07NA27344. This research is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA and has made use of data obtained with NuSTAR, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. We acknowledge the use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This work has made use of a collection of ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/).\n\nPublished - aa38317-20.pdf
",
"abstract": "Context. With an absorption column density on the order of 10\u00b2\u2074 cm\u207b\u00b2, IGR J16318\u22124848 is one of the most extreme cases of a highly obscured high mass X-ray binary. In addition to the overall continuum absorption, the source spectrum exhibits a strong iron and nickel fluorescence line complex at 6.4 keV. Previous empirical modeling of these features and comparison with radiative transfer simulations raised questions about the structure and covering fraction of the absorber and the profile of the fluorescence lines. \n\nAims. We aim at a self-consistent description of the continuum absorption, the absorption edges, and the fluorescence lines to constrain the properties of the absorbing material, such as ionization structure and geometry. We further investigate the effects of dust absorption on the observed spectra and the possibility of fluorescence emission from dust grains. \n\nMethods. We used XMM-Newton and NuSTAR spectra to first empirically constrain the incident continuum and fluorescence lines. Next we used XSTAR to construct a customized photoionization model where we vary the ionization parameter, column density, and covering fraction. In the third step we modeled the absorption and fluorescence in a dusty olivine absorber and employed both a simple analytical model for the fluorescence line emission and a Monte Carlo simulation of radiative transfer that generates line fluxes, which are very close to the observational data. \n\nResults. Our empirical spectral modeling is in agreement with previous works. Our second model, the single gas absorber does not describe the observational data. In particular, irrespective of the ionization state or column density of the absorber, a much higher covering fraction than previously estimated is needed to produce the strong fluorescence lines and the large continuum absorption. A dusty, spherical absorber (modeled as consisting of olivine dust, although the nature of dust cannot be constrained) is able to produce the observed continuum absorption and edges. \n\nConclusions. A dense, dusty absorber in the direct vicinity of the source consisting of dust offers a consistent description of both the strong continuum absorption and the strong emission features in the X-ray spectrum of IGR J16318\u22124848. In particular, for low optical depth of individual grains, which is the case for typical volume densities and grain size distribution models, the dust will contribute significantly to the fluorescence emission.",
"date": "2020-09",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "641",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A65",
"id_number": "CaltechAUTHORS:20200915-115017424",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200915-115017424",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "50 OR 1410"
},
{
"agency": "European Social Fund"
},
{
"agency": "Baden-W\u00fcrttemberg Ministry of Science, Research and the Arts"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC52-07NA27344"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1051/0004-6361/202038317",
"primary_object": {
"basename": "aa38317-20.pdf",
"url": "https://authors.library.caltech.edu/records/rs3y8-xzy67/files/aa38317-20.pdf"
},
"pub_year": "2020",
"author_list": "Ballhausen, Ralf; Lorenz, Maximilian; et al."
},
{
"id": "https://authors.library.caltech.edu/records/svj7e-sed54",
"eprint_id": 104380,
"eprint_status": "archive",
"datestamp": "2023-08-19 23:09:01",
"lastmod": "2026-03-28 21:09:32",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "L\u00f3pez-K-M",
"name": {
"family": "L\u00f3pez",
"given": "K. M."
},
"orcid": "0000-0002-5464-4632"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Roberts-T-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Moon-Dae-Sik",
"name": {
"family": "Moon",
"given": "D.-S."
},
"orcid": "0000-0003-4200-5064"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "NIR counterparts to ULXs (III): completing the photometric survey and selected spectroscopic results",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: black holes \u2013 infrared: stars \u2013 X-rays: individual: XMMU J024323.5+372038 \u2013X-rays: individual: 2E\n1402.4+5440 \u2013X-rays: individual: RX J073655.7+653542 \u2013X-rays: individual: CXOU J140314.3+541807",
"note": "\u00a9 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 May 31. Received 2020 May 27; in original form 2019 October 29. Published: 07 July 2020. \n\nBased on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme 0102.D-0529(A). \n\nWe are infinitely grateful to the anonymous referee for her/his thorough comments that greatly improved this manuscript. This research is based on observations made with: (a) the WHT operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof\u00edsica de Canarias; (b) ESO Telescopes at the La Silla Paranal Observatory; (c) the 5-m Hale Telescope at the Palomar Observatory; and (d) the Keck I Telescope at the W. M. Keck Observatory. We wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. KML would like to thank Mischa Schirmer for his invaluable help with the data reduction pipeline THELI and the setting/adding of new instruments to it. We have made use of the SIMBAD data base, operated at CDS, Strasbourg, France; of the NASA/IPAC Extragalactic Database (NED) that is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration; and of data obtained from the Chandra Data Archive and the Chandra Source Catalog. PGJ and KML acknowledge funding from the European Research Council under ERC Consolidator Grant agreement no. 647208. MH acknowledges the ESO fellowship programme. MAPT acknowledges support via a Ram\u00f3n y Cajal Fellowship (RYC-2015-17854) and support by the Spanish Ministry of Economy, Industry and Competitiveness under grant AYA2017-83216-P. TPR acknowledges funding from Science and Technology Facilities Council (STFC) as part of the consolidated grant ST/L00075X/1. DJW acknowledges support from an STFC Ernest Rutherford Fellowship. \n\nData Availability: The data underlying this article are available in Zenodo, at https://zenodo.org/record/3903160.\n\nPublished - staa1920.pdf
Accepted Version - 2006.02795.pdf
Supplemental Material - staa1920_supplemental_files.zip
",
"abstract": "We present results from the remaining sources in our search for near-infrared (NIR) candidate counterparts to ultraluminous X-ray sources (ULXs) within \u224310 Mpc. We observed 23 ULXs in 15 galaxies and detected NIR candidate counterparts to 6 of them. Two of these have an absolute magnitude consistent with a single red supergiant (RSG). Three counterparts are too bright for an RSG and spatially extended, and thus we classify them as stellar clusters. The other candidate is too faint for an RSG. Additionally, we present the results of our NIR spectroscopic follow-up of five sources: four originally classified as RSG and one as a stellar cluster on the basis of previous photometry. The stellar cluster candidate is actually a nebula. Of the four RSG candidates, one source has a broad H\u2009\u03b1 emission line redshifted by \u223cz = 1, making it a background active galactic nucleus (AGN). Two other sources show stellar spectra consistent with them being RSGs. The final RSG candidate is too faint to classify, but does not show strong (nebular) emission lines in its spectrum. After our search for NIR counterparts to 113 ULXs, where we detected a candidate counterpart for 38 ULXs, we have spectroscopically confirmed the nature of 12: 5 sources are nebulae, 1 source is not classified, 1 source is an AGN, and 5 are RSGs. These possible five ULX\u2013RSG binary systems would constitute \u2243(4\u00b12) per cent of the observed ULXs, a fraction almost four times larger than what was predicted by binary evolution simulations.",
"date": "2020-09",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "497",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "917-932",
"id_number": "CaltechAUTHORS:20200714-121112590",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200714-121112590",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "European Southern Observatory (ESO)"
},
{
"agency": "Ram\u00f3n y Cajal Fellowship",
"grant_number": "RYC-2015-17854"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2017-83216-P"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/L00075X/1"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa1920",
"primary_object": {
"basename": "2006.02795.pdf",
"url": "https://authors.library.caltech.edu/records/svj7e-sed54/files/2006.02795.pdf"
},
"related_objects": [
{
"basename": "staa1920.pdf",
"url": "https://authors.library.caltech.edu/records/svj7e-sed54/files/staa1920.pdf"
},
{
"basename": "staa1920_supplemental_files.zip",
"url": "https://authors.library.caltech.edu/records/svj7e-sed54/files/staa1920_supplemental_files.zip"
}
],
"pub_year": "2020",
"author_list": "L\u00f3pez, K. M.; Heida, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/256k3-jrc89",
"eprint_id": 104379,
"eprint_status": "archive",
"datestamp": "2023-08-19 23:08:53",
"lastmod": "2026-03-28 22:22:48",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Annuar-A",
"name": {
"family": "Annuar",
"given": "A."
},
"orcid": "0000-0003-0387-1429"
},
{
"id": "Alexander-D-M",
"name": {
"family": "Alexander",
"given": "D. M."
},
"orcid": "0000-0002-5896-6313"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Lansbury-G-B",
"name": {
"family": "Lansbury",
"given": "G. B."
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Asmus-D",
"name": {
"family": "Asmus",
"given": "D."
},
"orcid": "0000-0003-0220-2063"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Bauer-F-E",
"name": {
"family": "Bauer",
"given": "F. E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Boorman-P-G",
"name": {
"family": "Boorman",
"given": "P. G."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Brandt-W-N",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Chen-Chien-Ting-J",
"name": {
"family": "Chen",
"given": "C.-T. J."
},
"orcid": "0000-0002-4945-5079"
},
{
"id": "Del-Moro-A",
"name": {
"family": "Del Moro",
"given": "A."
}
},
{
"id": "Farrah-Duncan",
"name": {
"family": "Farrah",
"given": "D."
},
"orcid": "0000-0003-1748-2010"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "M. J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Lanz-L",
"name": {
"family": "Lanz",
"given": "L."
},
"orcid": "0000-0002-3249-8224"
},
{
"id": "Marchesi-S",
"name": {
"family": "Marchesi",
"given": "S."
},
"orcid": "0000-0001-5544-0749"
},
{
"id": "Masini-A",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Nardini-E",
"name": {
"family": "Nardini",
"given": "E."
},
"orcid": "0000-0001-9226-8992"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zappacosta-L",
"name": {
"family": "Zappacosta",
"given": "L."
},
"orcid": "0000-0002-4205-6884"
}
]
},
"title": "NuSTAR Observations of Four Nearby X-ray Faint AGN: Low Luminosity or Heavy Obscuration?",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 X-rays: individual: ESO 121-G6 \u2013X-rays: individual:NGC660 \u2013X-rays: individual:NGC3486 \u2013 X-rays: individual: NGC 5195",
"note": "\u00a9 2020 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 June 15. Received 2020 June 8; in original form 2020 March 23. Published: 27 June 2020. \n\nWe acknowledge financial support from the Ministry of Higher Education Malaysia Fundamental Research Grant Scheme grant code FRGS/1/2019/STG02/UKM/02/7 (AA), the Science and Technology Facilities Council grant codes ST/P000541/1 and ST/T000244/1 (DMA), and ST/R000506/1 (PG). FEB acknowledges support from the CONICYT grant CATA-Basal AFB-170002, FONDECYT Regular 1190818 and 1200495, and Chile's Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. DA acknowledges funding through the European Union's Horizon 2020 and Innovation programme under the Marie Sklodowska-Curie grant agreement no. 793499 (DUSTDEVILS). MB acknowledges support from the Black Hole Initiative at Harvard University, which is funded in part by the Gordon and Betty Moore Foundation (grant GBMF8273) and in part by the John Templeton Foundation. CR acknowledges support from the CONICYT+PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080, and Fondecyt Iniciacion grant 11190831. PB acknowledges financial support from the STFC and the Czech Science Foundation project no. 19-05599Y. EN acknowledges financial contribution from the agreement ASI-INAF n.2017-14-H.0 and partial support from the EU Horizon 2020 Marie Sk\u0142odowska-Curie grant agreement no. 664931. \n\nNuSTAR is a project led by the California Institute of Technology (Caltech), managed by the Jet Propulsion Laboratory (JPL), and funded by the National Aeronautics and Space Administration (NASA). We thank the NuSTAR Operations, Software and Calibrations teams for support with these observations. This research has made use of the NuSTAR Data Analysis Software (NUSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). The scientific results reported in this article are based on observations made by the Chandra X-ray Observatory and data obtained from the Chandra Data Archive. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application packages CIAO. This work was also based on observations obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. Besides these, we also used observations collected at the European Organisation for Astronomical Research in the Southern hemisphere under ESO programme 0101.B-0386(A). \n\nThis research made use of Astropy,12 a community-developed core Python package for Astronomy (Astropy Collaboration 2013; Astropy Collaboration 2018). We also used data obtained through the High Energy Astrophysics Science Archive Research Center (HEASARC) Online Service, provided by the NASA/Goddard Space Flight Center, and the NASA/IPAC extragalactic Database (NED) operated by JPL, Caltech under contract with NASA. \n\nFacilities: Chandra, Gemini, NuSTAR, Swift, VLT, WISE, and XMM\u2013Newton. \n\nData availability: The data used in this paper are publicly available to access and download as follows:\ni.\tX-ray data\na.\tFrom NASA's High Energy Astrophysics Science Archive Research Center (https://heasarc.gsfc.nasa.gov/docs/archive.html). Details of the observations, including the observation identification numbers, are listed in Table 2.\nii.\tMid-IR data\na.\tESO121-G6: From the Gemini Observatory Archive (https://archive.gemini.edu/searchform); Program ID: GS-2010B-Q-3; PI: F. Bauer.\nb.\tNGC 660: From the European Southern Observatory Science Archive Facility (http://archive.eso.org/eso/eso_archive_main.html); Program ID: 0101.B-0386(A); PI: A. Annuar.\n\nPublished - staa1820.pdf
Accepted Version - 2006.13583.pdf
",
"abstract": "We present NuSTAR (Nuclear Spectroscopic Telescope Array) observations of four active galactic nuclei (AGNs) located within 15 Mpc. These AGNs, namely ESO 121-G6, NGC 660, NGC 3486, and NGC 5195, have observed X-ray luminosities of L_(2\u201310\u2009keV,obs) \u2272 10\u00b3\u2079 erg s\u207b\u00b9, classifying them as low-luminosity AGN (LLAGN). We perform broad-band X-ray spectral analysis for the AGN by combining our NuSTAR data with Chandra or XMM\u2013Newton observations to directly measure their column densities (N_H) and infer their intrinsic power. We complement our X-ray data with archival and new high-angular resolution mid-infrared (mid-IR) data for all objects, except NGC 5195. Based on our X-ray spectral analysis, we found that both ESO 121-G6 and NGC 660 are heavily obscured (N_H > 10\u00b2\u00b3 cm\u207b\u00b2; L_(2\u201310\u2009keV,int) \u223c 10\u2074\u00b9 erg s\u207b\u00b9), and NGC 660 may be Compton thick. We also note that the X-ray flux and spectral slope for ESO 121-G6 have significantly changed over the last decade, indicating significant changes in the obscuration and potentially accretion rate. On the other hand, NGC 3486 and NGC 5195 appear to be unobscured and just mildly obscured, respectively, with L_(2\u201310\u2009keV,int) < 10\u00b3\u2079 erg s\u207b\u00b9, i.e. genuine LLAGN. Both of the heavily obscured AGNs have L_(bol) > 10\u2074\u00b9 erg s\u207b\u00b9 and \u03bb_(Edd) \u2273 10\u207b\u00b3, and are detected in high-angular resolution mid-IR imaging, indicating the presence of obscuring dust on nuclear scale. NGC 3486, however, is undetected in high-resolution mid-IR imaging, and the current data do not provide stringent constraints on the presence or absence of obscuring nuclear dust in the AGN.",
"date": "2020-09",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "497",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "229-245",
"id_number": "CaltechAUTHORS:20200714-115518491",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200714-115518491",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Ministry of Education (Malaysia)",
"grant_number": "FRGS/1/2019/STG02/UKM/02/7"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/P000541/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/T000244/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/R000506/1"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1200495"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "793499"
},
{
"agency": "Harvard University"
},
{
"agency": "Gordon and Betty Moore Foundation",
"grant_number": "GBMF8273"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "2017 PAI77170080"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "Czech Science Foundation",
"grant_number": "19-05599Y"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "664931"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa1820",
"primary_object": {
"basename": "2006.13583.pdf",
"url": "https://authors.library.caltech.edu/records/256k3-jrc89/files/2006.13583.pdf"
},
"related_objects": [
{
"basename": "staa1820.pdf",
"url": "https://authors.library.caltech.edu/records/256k3-jrc89/files/staa1820.pdf"
}
],
"pub_year": "2020",
"author_list": "Annuar, A.; Alexander, D. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0c0te-08q10",
"eprint_id": 104912,
"eprint_status": "archive",
"datestamp": "2023-08-22 06:01:47",
"lastmod": "2026-03-29 14:18:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Homan-J",
"name": {
"family": "Homan",
"given": "Jeroen"
},
"orcid": "0000-0001-8371-2713"
},
{
"id": "Neilsen-J",
"name": {
"family": "Neilsen",
"given": "Joseph"
},
"orcid": "0000-0002-8247-786X"
},
{
"id": "Marcel-G",
"name": {
"family": "Marcel",
"given": "Gr\u00e9goire"
},
"orcid": "0000-0003-1780-5641"
},
{
"id": "Ludlam-R-M",
"name": {
"family": "Ludlam",
"given": "Renee M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Tombesi-F",
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"id": "Cackett-E-M",
"name": {
"family": "Cackett",
"given": "Edward M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Remillard-R-A",
"name": {
"family": "Remillard",
"given": "Ron A."
},
"orcid": "0000-0003-4815-0481"
}
]
},
"title": "Relativistic Reflection and Reverberation in GX 339\u20134 with NICER and NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Black holes; High energy astrophysics; Astrophysical black holes; Stellar mass black holes; Low-mass X-ray binary stars; X-ray astronomy",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 October 2; revised 2020 June 17; accepted 2020 June 19; published 2020 August 11. \n\nJ.W., E.K., and J.A.G. acknowledges support from NASA grant 80NSSC17K0515 and thank the International Space Science Institute (ISSI) and participants of the ISSI Workshop \"Sombreros and Lampposts: The Geometry of Accretion onto Black Holes\" for fruitful discussions. J.A.G. is thankful for support from the Alexander von Humboldt Foundation. E.M.C. gratefully acknowledges support from the National Science Foundation, CAREER award No. AST-1351222. R.M.L. acknowledges the support of NASA through Hubble Fellowship Program grant HST-HF2-51440.001.\n\nPublished - Wang_2020_ApJ_899_44.pdf
Accepted Version - 1910.01245.pdf
",
"abstract": "We analyze seven Neutron Star Interior Composition Interior Explorer (NICER) and Nuclear Spectroscopic Telescope Array epochs of the black hole X-ray binary GX 339\u20134 in the hard state during its two most recent hard-only outbursts in 2017 and 2019. These observations cover the 1\u2013100 keV unabsorbed luminosities between 0.3% and 2.1% of the Eddington limit. With NICER's negligible pileup, high count rate, and unprecedented time resolution, we perform a spectral-timing analysis and spectral modeling using relativistic and distant reflection models. Our spectral fitting shows that as the inner disk radius moves inward, the thermal disk emission increases in flux and temperature, the disk becomes more highly ionized, and the reflection fraction increases. This coincides with the inner disk increasing its radiative efficiency around ~1% Eddington. We see a hint of the hysteresis effect at ~0.3% of Eddington; the inner radius is significantly truncated during the rise (>49R_g ), while only a mild truncation (~5R_g ) is found during the decay. At higher frequencies (2\u20137 Hz) in the highest-luminosity epoch, a soft lag is present whose energy dependence reveals a thermal reverberation lag with an amplitude similar to previous findings for this source. We also discuss the plausibility of the hysteresis effect and the debate of the disk truncation problem in the hard state.",
"date": "2020-08-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "899",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 44",
"id_number": "CaltechAUTHORS:20200811-131238093",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200811-131238093",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NSF",
"grant_number": "AST-1351222"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ab9ec3",
"primary_object": {
"basename": "1910.01245.pdf",
"url": "https://authors.library.caltech.edu/records/0c0te-08q10/files/1910.01245.pdf"
},
"related_objects": [
{
"basename": "Wang_2020_ApJ_899_44.pdf",
"url": "https://authors.library.caltech.edu/records/0c0te-08q10/files/Wang_2020_ApJ_899_44.pdf"
}
],
"pub_year": "2020",
"author_list": "Wang, Jingyi; Kara, Erin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7vxkb-bm685",
"eprint_id": 97735,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:37:04",
"lastmod": "2026-03-30 14:24:07",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Assef-R-J",
"name": {
"family": "Assef",
"given": "R. J."
},
"orcid": "0000-0002-9508-3667"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Bauer-F-E",
"name": {
"family": "Bauer",
"given": "F. E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Blain-A-W",
"name": {
"family": "Blain",
"given": "A. W."
},
"orcid": "0000-0001-7489-5167"
},
{
"id": "D\u00edaz-Santos-T",
"name": {
"family": "D\u00edaz-Santos",
"given": "T."
},
"orcid": "0000-0003-0699-6083"
},
{
"id": "Eisenhardt-P-R-M",
"name": {
"family": "Eisenhardt",
"given": "P. R. M."
}
},
{
"id": "Hickox-R-C",
"name": {
"family": "Hickox",
"given": "R. C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Jun-Hyunsung-David",
"name": {
"family": "Jun",
"given": "H. D."
},
"orcid": "0000-0003-1470-5901"
},
{
"id": "Psychogyios-A",
"name": {
"family": "Psychogyios",
"given": "A."
}
},
{
"id": "Tsai-Chao-Wei",
"name": {
"family": "Tsai",
"given": "C.-W."
},
"orcid": "0000-0002-9390-9672"
},
{
"id": "Wu-Jingwen",
"name": {
"family": "Wu",
"given": "J. W."
},
"orcid": "0000-0001-7808-3756"
}
]
},
"title": "Hot Dust-Obscured Galaxies with Excess Blue Light",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galaxies; Galaxy evolution; High-redshift galaxies; Quasars; Infrared galaxies",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 April 25; revised 2020 May 26; accepted 2020 May 28; published 2020 July 8. \n\nWe thank J. Comerford and B. Weiner for carrying out observations presented in this article. We also thank the anonymous referee for the comments and suggestions to improve the manuscript. R.J.A. was supported by FONDECYT grant Nos. 1151408 and 1191124. D.J.W. acknowledges financial support from the STFC Ernest Rutherford fellowship. H.D.J. was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1A6A3A04005158). F.E.B. acknowledges support from CONICYT-Chile (Basal AFB-170002) and the Ministry of Economy, Development and Tourism's Millenium Science Initiative through grant IC120009, awarded to The Millenium Institute of Astrophysics, MAS. T.D-S. acknowledges support from the CASSACA and CONICYT fund CAS-CONICYT Call 2018. J.W. is supported by the NSFC grant 11690024 and SPRP CAS grant XDB23000000. C.-T. was supported by a grant from the NSFC (No. 11973051). This work is based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program #14358. Support for program #14358 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. The scientific results reported in this article are based to a significant degree on data obtained from the Chandra X-ray Observatory and observations made by the Chandra X-ray Observatory and published previously in cited articles. Support for this work was provided by the National Aeronautics and Space Administration through Chandra Award Number 17700696 issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. The Pan-STARRS1 Surveys (PS1) have been made possible through contributions of the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation under grant No. AST-1238877, the University of Maryland, and Eotvos Lorand University (ELTE) and the Los Alamos National Laboratory. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III website is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. Some of the observations reported here were obtained at the MMT Observatory, a joint facility of the Smithsonian Institution and the University of Arizona.\n\nPublished - Assef_2020_ApJ_897_112.pdf
Submitted - 1905.04320.pdf
",
"abstract": "Hot dust-obscured galaxies (Hot DOGs) are among the most luminous galaxies in the universe. Powered by highly obscured, possibly Compton-thick, active galactic nuclei (AGNs), Hot DOGs are characterized by spectral energy distributions that are very red in the mid-infrared yet dominated by the host galaxy stellar emission in the UV and optical. An earlier study identified a subsample of Hot DOGs with significantly enhanced UV emission. One target, W0204\u20130506, was studied in detail and, based on Chandra observations, it was concluded that the enhanced emission was most likely due to either extreme unobscured star formation (star formation rate > 1000 M_\u2299 yr\u207b\u00b9) or to light from the highly obscured AGN scattered by gas or dust into our line of sight. Here, we present a follow-up study of W0204\u20130506 as well as two more Hot DOGs with excess UV emission. For the two new objects we obtained Chandra/ACIS-S observations, and for all three targets we obtained Hubble Space Telescope/WFC3 F555W and F160W imaging. The analysis of these observations, combined with multiwavelength photometry and UV/optical spectroscopy suggests that UV emission is most likely dominated by light from the central highly obscured, hyperluminous AGN that has been scattered into our line of sight, by either gas or dust. We cannot decisively rule out, however, that star formation or a second AGN in the system may significantly contribute to the UV excess of these targets.",
"date": "2020-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "897",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 112",
"id_number": "CaltechAUTHORS:20190809-153952098",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190809-153952098",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1151408"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1191124"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2017R1A6A3A04005158"
},
{
"agency": "Basal-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11690024"
},
{
"agency": "Chinese Academy of Sciences",
"grant_number": "XDB23000000"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11973051"
},
{
"agency": "NASA",
"grant_number": "NAS 5-26555"
},
{
"agency": "NASA",
"grant_number": "17700696"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NNX08AR22G"
},
{
"agency": "NSF",
"grant_number": "AST-1238877"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Participating Institutions"
},
{
"agency": "Department of Energy (DOE)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab9814",
"primary_object": {
"basename": "1905.04320.pdf",
"url": "https://authors.library.caltech.edu/records/7vxkb-bm685/files/1905.04320.pdf"
},
"related_objects": [
{
"basename": "Assef_2020_ApJ_897_112.pdf",
"url": "https://authors.library.caltech.edu/records/7vxkb-bm685/files/Assef_2020_ApJ_897_112.pdf"
}
],
"pub_year": "2020",
"author_list": "Assef, R. J.; Brightman, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4e2px-xpv22",
"eprint_id": 103713,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:34:58",
"lastmod": "2026-03-30 13:59:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Sokolova-Lapa-E",
"name": {
"family": "Sokolova-Lapa",
"given": "Ekaterina"
}
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Madej-J",
"name": {
"family": "Madej",
"given": "Jerzy"
},
"orcid": "0000-0001-8417-1509"
},
{
"id": "R\u00f3\u017ca\u0144ska-A",
"name": {
"family": "R\u00f3\u017ca\u0144ska",
"given": "Agata"
},
"orcid": "0000-0002-5275-4096"
},
{
"id": "Majczyna-A",
"name": {
"family": "Majczyna",
"given": "Agnieszka"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "Accurate Treatment of Comptonization in X-ray Illuminated Accretion Disks",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Stellar accretion disks; Atomic spectroscopy; Radiative transfer simulations; Astronomical simulations; Black hole physics",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2020 March 14; revised 2020 May 7; accepted 2020 May 8; published 2020 July 2. \n\nThis work was been partially supported under NASA No. NNG08FD60C. J.A.G. acknowledges support from NASA ATP grant No. 80NSSC20K0540 and from the Alexander von Humboldt Foundation. E.K.S and J.W. have been supported by DFG grant WI 1860/11-1. A.R., J.M., and A.M. were supported by grants No. 2015/17/B/ST9/03422 and 2015/18/M/ST9/00541 from the Polish National Science Center. \n\nsoftware xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), Matplotlib (version 3.1.3, Hunter 2007), NumPy (version 1.18.1, Oliphant 2006).\n\nPublished - Garc\u00eda_2020_ApJ_897_67.pdf
Submitted - 2005.04852.pdf
",
"abstract": "A large fraction of accreting black hole and neutron star systems present clear evidence of the reprocessing of X-rays in the atmosphere of an optically thick accretion disk. The main hallmarks of X-ray reflection include fluorescent K-shell emission lines from iron (~6.4\u20136.9 keV), the absorption iron K-edge (~7\u20139 keV), and a broad featureless component known as the Compton hump (~20\u201340 keV). This Compton hump is produced as the result of the scattering of high-energy photons (E \u2273 10 keV) of the relatively colder electrons (T_e ~ 10\u2075\u201310\u2077 K) in the accretion disk, in combination with photoelectric absorption from iron. The treatment of this process in most current models of ionized X-ray reflection has been done using an approximated Gaussian redistribution kernel. This approach works sufficiently well up to ~100 keV, but it becomes largely inaccurate at higher energies and at relativistic temperatures (T_e ~ 10\u2079 K). We present new calculations of X-ray reflection using a modified version of our code xillver, including an accurate solution for Compton scattering of the reflected unpolarized photons in the disk atmosphere. This solution takes into account quantum electrodynamic and relativistic effects allowing the correct treatment of high photon energies and electron temperatures. We show new reflection spectra computed with this model, and discuss the improvements achieved in reproducing the correct shape of the Compton hump, the discrepancies with previous calculations, and the expected impact of these new models in the interpretation of observational data.",
"date": "2020-07-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "897",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 67",
"id_number": "CaltechAUTHORS:20200604-151447853",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200604-151447853",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA",
"grant_number": "80NSSC20K0540"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "WI 1860/11-1"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2015/17/B/ST9/03422"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2015/18/M/ST9/00541"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab919b",
"primary_object": {
"basename": "2005.04852.pdf",
"url": "https://authors.library.caltech.edu/records/4e2px-xpv22/files/2005.04852.pdf"
},
"related_objects": [
{
"basename": "Garc\u00eda_2020_ApJ_897_67.pdf",
"url": "https://authors.library.caltech.edu/records/4e2px-xpv22/files/Garc\u00eda_2020_ApJ_897_67.pdf"
}
],
"pub_year": "2020",
"author_list": "Garc\u00eda, Javier A.; Sokolova-Lapa, Ekaterina; et al."
},
{
"id": "https://authors.library.caltech.edu/records/cvzck-kq224",
"eprint_id": 104266,
"eprint_status": "archive",
"datestamp": "2023-08-19 22:06:51",
"lastmod": "2026-03-30 06:46:33",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Abdalla-H",
"name": {
"family": "Abdalla",
"given": "H."
}
},
{
"name": {
"family": "Adam",
"given": "R."
}
},
{
"name": {
"family": "Aharonian",
"given": "F."
}
},
{
"name": {
"family": "Ait Benkhali",
"given": "F."
}
},
{
"name": {
"family": "Ang\u00fcner",
"given": "E. O."
}
},
{
"name": {
"family": "Arakawa",
"given": "M."
}
},
{
"name": {
"family": "Arcaro",
"given": "C."
}
},
{
"name": {
"family": "Armand",
"given": "C."
}
},
{
"name": {
"family": "Ashkar",
"given": "H."
}
},
{
"name": {
"family": "Backes",
"given": "M."
}
},
{
"name": {
"family": "Barbosa Martins",
"given": "V."
}
},
{
"name": {
"family": "Barnard",
"given": "M."
}
},
{
"name": {
"family": "Becherini",
"given": "Y."
}
},
{
"name": {
"family": "Berge",
"given": "D."
}
},
{
"name": {
"family": "Bernl\u00f6hr",
"given": "K."
}
},
{
"name": {
"family": "Blackwell",
"given": "R."
}
},
{
"name": {
"family": "B\u00f6ttcher",
"given": "M."
}
},
{
"name": {
"family": "Boisson",
"given": "C."
}
},
{
"name": {
"family": "Bolmont",
"given": "J."
}
},
{
"name": {
"family": "Bonnefoy",
"given": "S."
}
},
{
"name": {
"family": "Bregeon",
"given": "J."
}
},
{
"name": {
"family": "Breuhaus",
"given": "M."
}
},
{
"name": {
"family": "Brun",
"given": "F."
}
},
{
"name": {
"family": "Brun",
"given": "P."
}
},
{
"name": {
"family": "Bryan",
"given": "M."
}
},
{
"name": {
"family": "B\u00fcchele",
"given": "M."
}
},
{
"name": {
"family": "Bulik",
"given": "T."
}
},
{
"name": {
"family": "Bylund",
"given": "T."
}
},
{
"name": {
"family": "Caroff",
"given": "S."
}
},
{
"name": {
"family": "Carosi",
"given": "A."
}
},
{
"name": {
"family": "Casanova",
"given": "S."
}
},
{
"name": {
"family": "Cerruti",
"given": "M."
}
},
{
"name": {
"family": "Chand",
"given": "T."
}
},
{
"name": {
"family": "Chandra",
"given": "S."
}
},
{
"name": {
"family": "Chen",
"given": "A."
}
},
{
"name": {
"family": "Colafrancesco",
"given": "S."
}
},
{
"name": {
"family": "Cury\u0142o",
"given": "M."
}
},
{
"name": {
"family": "Davids",
"given": "I. D."
}
},
{
"name": {
"family": "Deil",
"given": "C."
}
},
{
"name": {
"family": "Devin",
"given": "J."
}
},
{
"name": {
"family": "deWilt",
"given": "P."
}
},
{
"name": {
"family": "Dirson",
"given": "L."
}
},
{
"name": {
"family": "Djannati-Ata\u00ef",
"given": "A."
}
},
{
"name": {
"family": "Dmytriiev",
"given": "A."
}
},
{
"name": {
"family": "Donath",
"given": "A."
}
},
{
"name": {
"family": "Doroshenko",
"given": "V."
}
},
{
"name": {
"family": "Dyks",
"given": "J."
}
},
{
"name": {
"family": "Egberts",
"given": "K."
}
},
{
"name": {
"family": "Emery",
"given": "G."
}
},
{
"name": {
"family": "Ernenwein",
"given": "J.-P."
}
},
{
"name": {
"family": "Eschbach",
"given": "S."
}
},
{
"name": {
"family": "Feijen",
"given": "K."
}
},
{
"name": {
"family": "Fegan",
"given": "S."
}
},
{
"name": {
"family": "Fiasson",
"given": "A."
}
},
{
"name": {
"family": "Fontaine",
"given": "G."
}
},
{
"name": {
"family": "Funk",
"given": "S."
}
},
{
"name": {
"family": "F\u00fc\u00dfling",
"given": "M."
}
},
{
"name": {
"family": "Gabici",
"given": "S."
}
},
{
"name": {
"family": "Gallant",
"given": "Y. A."
}
},
{
"name": {
"family": "Gat\u00e9",
"given": "F."
}
},
{
"name": {
"family": "Giavitto",
"given": "G."
}
},
{
"name": {
"family": "Giunti",
"given": "L."
}
},
{
"name": {
"family": "Glawion",
"given": "D."
}
},
{
"name": {
"family": "Glicenstein",
"given": "J. F."
}
},
{
"name": {
"family": "Gottschall",
"given": "D."
}
},
{
"name": {
"family": "Grondin",
"given": "M.-H."
}
},
{
"name": {
"family": "Hahn",
"given": "J."
}
},
{
"name": {
"family": "Haupt",
"given": "M."
}
},
{
"name": {
"family": "Heinzelmann",
"given": "G."
}
},
{
"name": {
"family": "Henri",
"given": "G."
}
},
{
"name": {
"family": "Hermann",
"given": "G."
}
},
{
"name": {
"family": "Hinton",
"given": "J. A."
}
},
{
"name": {
"family": "Hofmann",
"given": "W."
}
},
{
"name": {
"family": "Hoischen",
"given": "C."
}
},
{
"name": {
"family": "Holch",
"given": "T. L."
}
},
{
"name": {
"family": "Holler",
"given": "M."
}
},
{
"name": {
"family": "Horns",
"given": "D."
}
},
{
"name": {
"family": "Huber",
"given": "D."
}
},
{
"name": {
"family": "Iwasaki",
"given": "H."
}
},
{
"name": {
"family": "Jamrozy",
"given": "M."
}
},
{
"name": {
"family": "Jankowsky",
"given": "D."
}
},
{
"name": {
"family": "Jankowsky",
"given": "F."
}
},
{
"name": {
"family": "Jardin-Blicq",
"given": "A."
}
},
{
"name": {
"family": "Jung-Richardt",
"given": "I."
}
},
{
"name": {
"family": "Kastendieck",
"given": "M. A."
}
},
{
"name": {
"family": "Katarzy\u0144ski",
"given": "K."
}
},
{
"name": {
"family": "Katsuragawa",
"given": "M."
}
},
{
"name": {
"family": "Katz",
"given": "U."
}
},
{
"name": {
"family": "Khangulyan",
"given": "D."
}
},
{
"name": {
"family": "Kh\u00e9lifi",
"given": "B."
}
},
{
"name": {
"family": "King",
"given": "J."
}
},
{
"name": {
"family": "Klepser",
"given": "S."
}
},
{
"name": {
"family": "Klu\u017aniak",
"given": "W."
}
},
{
"name": {
"family": "Komin",
"given": "Nu."
}
},
{
"name": {
"family": "Kosack",
"given": "K."
}
},
{
"name": {
"family": "Kostunin",
"given": "D."
}
},
{
"name": {
"family": "Kreter",
"given": "M."
}
},
{
"name": {
"family": "Lamanna",
"given": "G."
}
},
{
"name": {
"family": "Lemi\u00e8re",
"given": "A."
}
},
{
"name": {
"family": "Lemoine-Goumard",
"given": "M."
}
},
{
"name": {
"family": "Lenain",
"given": "J.-P."
}
},
{
"name": {
"family": "Leser",
"given": "E."
}
},
{
"name": {
"family": "Levy",
"given": "C."
}
},
{
"name": {
"family": "Lohse",
"given": "T."
}
},
{
"name": {
"family": "Lypova",
"given": "I."
}
},
{
"name": {
"family": "Mackey",
"given": "J."
}
},
{
"name": {
"family": "Majumdar",
"given": "J."
}
},
{
"name": {
"family": "Malyshev",
"given": "D."
}
},
{
"name": {
"family": "Marandon",
"given": "V."
}
},
{
"name": {
"family": "Marcowith",
"given": "A."
}
},
{
"name": {
"family": "Mares",
"given": "A."
}
},
{
"name": {
"family": "Mariaud",
"given": "C."
}
},
{
"name": {
"family": "Mart\u00ed-Devesa",
"given": "G."
}
},
{
"name": {
"family": "Marx",
"given": "R."
}
},
{
"name": {
"family": "Maurin",
"given": "G."
}
},
{
"name": {
"family": "Meintjes",
"given": "P. J."
}
},
{
"name": {
"family": "Mitchell",
"given": "A. M. W."
}
},
{
"name": {
"family": "Moderski",
"given": "R."
}
},
{
"name": {
"family": "Mohamed",
"given": "M."
}
},
{
"name": {
"family": "Mohrmann",
"given": "L."
}
},
{
"name": {
"family": "Moore",
"given": "C."
}
},
{
"name": {
"family": "Moulin",
"given": "E."
}
},
{
"name": {
"family": "Muller",
"given": "J."
}
},
{
"name": {
"family": "Murach",
"given": "T."
}
},
{
"name": {
"family": "Nakashima",
"given": "S."
}
},
{
"name": {
"family": "de Naurois",
"given": "M."
}
},
{
"name": {
"family": "Ndiyavala",
"given": "H."
}
},
{
"name": {
"family": "Niederwanger",
"given": "F."
}
},
{
"name": {
"family": "Niemiec",
"given": "J."
}
},
{
"name": {
"family": "Oakes",
"given": "L."
}
},
{
"name": {
"family": "O'Brien",
"given": "P."
}
},
{
"name": {
"family": "Odaka",
"given": "H."
}
},
{
"name": {
"family": "Ohm",
"given": "S."
}
},
{
"name": {
"family": "de Ona Wilhelmi",
"given": "E."
}
},
{
"name": {
"family": "Ostrowski",
"given": "M."
}
},
{
"name": {
"family": "Oya",
"given": "I."
}
},
{
"name": {
"family": "Panter",
"given": "M."
}
},
{
"name": {
"family": "Parsons",
"given": "R. D."
}
},
{
"name": {
"family": "Perennes",
"given": "C."
}
},
{
"name": {
"family": "Petrucci",
"given": "P.-O."
}
},
{
"name": {
"family": "Peyaud",
"given": "B."
}
},
{
"name": {
"family": "Piel",
"given": "Q."
}
},
{
"name": {
"family": "Pita",
"given": "S."
}
},
{
"name": {
"family": "Poireau",
"given": "V."
}
},
{
"name": {
"family": "Priyana Noel",
"given": "A."
}
},
{
"name": {
"family": "Prokhorov",
"given": "D. A."
}
},
{
"name": {
"family": "Prokoph",
"given": "H."
}
},
{
"name": {
"family": "P\u00fchlhofer",
"given": "G."
}
},
{
"name": {
"family": "Punch",
"given": "M."
}
},
{
"name": {
"family": "Quirrenbach",
"given": "A."
}
},
{
"name": {
"family": "Raab",
"given": "S."
}
},
{
"name": {
"family": "Rauth",
"given": "R."
}
},
{
"name": {
"family": "Reimer",
"given": "A."
}
},
{
"name": {
"family": "Reimer",
"given": "O."
}
},
{
"name": {
"family": "Remy",
"given": "Q."
}
},
{
"name": {
"family": "Renaud",
"given": "M."
}
},
{
"name": {
"family": "Rieger",
"given": "F."
}
},
{
"name": {
"family": "Rinchiuso",
"given": "L."
}
},
{
"name": {
"family": "Romoli",
"given": "C."
}
},
{
"name": {
"family": "Rowell",
"given": "G."
}
},
{
"name": {
"family": "Rudak",
"given": "B."
}
},
{
"name": {
"family": "Ruiz-Velasco",
"given": "E."
}
},
{
"name": {
"family": "Sahakian",
"given": "V."
}
},
{
"name": {
"family": "Sailer",
"given": "S."
}
},
{
"name": {
"family": "Saito",
"given": "S."
}
},
{
"name": {
"family": "Sanchez",
"given": "D. A."
}
},
{
"name": {
"family": "Santangelo",
"given": "A."
}
},
{
"name": {
"family": "Sasaki",
"given": "M."
}
},
{
"name": {
"family": "Schlickeiser",
"given": "R."
}
},
{
"name": {
"family": "Sch\u00fcssler",
"given": "F."
}
},
{
"name": {
"family": "Schulz",
"given": "A."
}
},
{
"name": {
"family": "Schutte",
"given": "H. M."
}
},
{
"name": {
"family": "Schwanke",
"given": "U."
}
},
{
"name": {
"family": "Schwemmer",
"given": "S."
}
},
{
"name": {
"family": "Seglar-Arroyo",
"given": "M."
}
},
{
"name": {
"family": "Senniappan",
"given": "M."
}
},
{
"name": {
"family": "Seyffert",
"given": "A. S."
}
},
{
"name": {
"family": "Shafi",
"given": "N."
}
},
{
"name": {
"family": "Shiningayamwe",
"given": "K."
}
},
{
"name": {
"family": "Simoni",
"given": "R."
}
},
{
"name": {
"family": "Sinha",
"given": "A."
}
},
{
"name": {
"family": "Sol",
"given": "H."
}
},
{
"name": {
"family": "Specovius",
"given": "A."
}
},
{
"name": {
"family": "Spir-Jacob",
"given": "M."
}
},
{
"name": {
"family": "Stawarz",
"given": "\u0141."
}
},
{
"name": {
"family": "Steenkamp",
"given": "R."
}
},
{
"name": {
"family": "Stegmann",
"given": "C."
}
},
{
"name": {
"family": "Steppa",
"given": "C."
}
},
{
"name": {
"family": "Takahashi",
"given": "T."
}
},
{
"name": {
"family": "Tavernier",
"given": "T."
}
},
{
"name": {
"family": "Taylor",
"given": "A. M."
}
},
{
"name": {
"family": "Terrier",
"given": "R."
}
},
{
"name": {
"family": "Tiziani",
"given": "D."
}
},
{
"name": {
"family": "Tluczykont",
"given": "M."
}
},
{
"name": {
"family": "Trichard",
"given": "C."
}
},
{
"name": {
"family": "Tsirou",
"given": "M."
}
},
{
"name": {
"family": "Tsuji",
"given": "N."
}
},
{
"name": {
"family": "Tuffs",
"given": "R."
}
},
{
"name": {
"family": "Uchiyama",
"given": "Y."
}
},
{
"name": {
"family": "van der Walt",
"given": "D. J."
}
},
{
"name": {
"family": "van Eldik",
"given": "C."
}
},
{
"name": {
"family": "van Rensburg",
"given": "C."
}
},
{
"name": {
"family": "van Soelen",
"given": "B."
}
},
{
"name": {
"family": "Vasileiadis",
"given": "G."
}
},
{
"name": {
"family": "Veh",
"given": "J."
}
},
{
"name": {
"family": "Venter",
"given": "C."
}
},
{
"name": {
"family": "Vincent",
"given": "P."
}
},
{
"name": {
"family": "Vink",
"given": "J."
}
},
{
"name": {
"family": "V\u00f6lk",
"given": "H. J."
}
},
{
"name": {
"family": "Vuillaume",
"given": "T."
}
},
{
"name": {
"family": "Wadiasingh",
"given": "Z."
}
},
{
"name": {
"family": "Wagner",
"given": "S. J."
}
},
{
"name": {
"family": "White",
"given": "R."
}
},
{
"name": {
"family": "Wierzcholska",
"given": "A."
}
},
{
"name": {
"family": "Yang",
"given": "R."
}
},
{
"name": {
"family": "Yoneda",
"given": "H."
}
},
{
"name": {
"family": "Zacharias",
"given": "M."
}
},
{
"name": {
"family": "Zanin",
"given": "R."
}
},
{
"name": {
"family": "Zdziarski",
"given": "A. A."
}
},
{
"name": {
"family": "Zech",
"given": "A."
}
},
{
"name": {
"family": "Zorn",
"given": "J."
}
},
{
"name": {
"family": "\u017bywucka",
"given": "N."
}
},
{
"name": {
"family": "Madejski",
"given": "G. M."
}
},
{
"name": {
"family": "Nalewajko",
"given": "K."
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"name": {
"family": "Chiang",
"given": "J."
}
},
{
"name": {
"family": "Balokovi\u0107",
"given": "M."
}
},
{
"name": {
"family": "Paneque",
"given": "D."
}
},
{
"name": {
"family": "Furniss",
"given": "A. K."
}
},
{
"name": {
"family": "Hayashida",
"given": "M."
}
},
{
"name": {
"family": "Urry",
"given": "C. M."
}
},
{
"name": {
"family": "Ajello",
"given": "M."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Giebels",
"given": "B."
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "K."
},
"orcid": "0000-0001-5800-5531"
},
{
"name": {
"family": "Giommi",
"given": "P."
}
},
{
"name": {
"family": "Perri",
"given": "M."
}
},
{
"name": {
"family": "Puccetti",
"given": "S."
}
},
{
"name": {
"family": "Zoglauer",
"given": "A."
}
},
{
"name": {
"family": "Tagliaferri",
"given": "G."
}
}
]
},
"title": "Simultaneous observations of the blazar PKS 2155\u2212304 from ultra-violet to TeV energies",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "BL Lacertae objects: individual: PKS 2155-304 \u2013 astroparticle physics",
"note": "\u00a9 2020 H. Abdalla et al. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nReceived 11 October 2019; Accepted 12 December 2019; Published online 07 July 2020. \n\nThe support of the Namibian authorities and of the University of Namibia in facilitating the construction and operation of H.E.S.S. is gratefully acknowledged, as is the support by the German Ministry for Education and Research (BMBF), the Max Planck Society, the German Research Foundation (DFG), the Helmholtz Association, the Alexander von Humboldt Foundation, the French Ministry of Higher Education, Research and Innovation, the Centre National de la Recherche Scientifique (CNRS/IN2P3 and CNRS/INSU), the Commissariat \u00e0 l'\u00e9nergie atomique et aux \u00e9nergies alternatives (CEA), the U.K. Science and Technology Facilities Council (STFC), the Knut and Alice Wallenberg Foundation, the National Science Centre, Poland grant no. 2016/22/M/ST9/00382, the South African Department of Science and Technology and National Research Foundation, the University of Namibia, the National Commission on Research, Science & Technology of Namibia (NCRST), the Austrian Federal Ministry of Education, Science and Research and the Austrian Science Fund (FWF), the Australian Research Council (ARC), the Japan Society for the Promotion of Science and by the University of Amsterdam. We appreciate the excellent work of the technical support staff in Berlin, Zeuthen, Heidelberg, Palaiseau, Paris, Saclay, T\u00fcbingen and in Namibia in the construction and operation of the equipment. This work benefited from services provided by the H.E.S.S. Virtual Organisation, supported by the national resource providers of the EGI Federation. The Fermi-LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat \u00e0 l'Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucl\u00e9aire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K. A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase from the following agencies is also gratefully acknowledged: the Istituto Nazionale di Astrofisica in Italy and and the Centre National d'Etudes Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515. This work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research made use of Enrico, a community-developed Python package to simplify Fermi-LAT analysis (Sanchez & Deil 2013). This research has made use of the VizieR catalogue access tool, CDS, Strasbourg, France. The original description of the VizieR service was published in A&AS 143, 23. This work has been done thanks to the facilities offered by the Universit\u00e9 Savoie Mont Blanc MUST computing center. M. Cerruti has received financial support through the Postdoctoral Junior Leader Fellowship Programme from la Caixa Banking Foundation, grant n. LCF/BQ/LI18/11630012. M. B. gratefully acknowledges financial support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program (grant NNX14AQ07H), and from the Black Hole Initiative at Harvard University, which is funded through a grant from the John Templeton Foundation.\n\nPublished - aa36900-19.pdf
Accepted Version - 1912.07273.pdf
",
"abstract": "Here we report the results of the first ever contemporaneous multi-wavelength observation campaign on the BL Lac object PKS 2155\u2212304 involving Swift, NuSTAR, Fermi-LAT, and H.E.S.S. The use of these instruments allows us to cover a broad energy range, which is important for disentangling the different radiative mechanisms. The source, observed from June 2013 to October 2013, was found in a low flux state with respect to previous observations but exhibited highly significant flux variability in the X-rays. The high-energy end of the synchrotron spectrum can be traced up to 40 keV without significant contamination by high-energy emission. A one-zone synchrotron self-Compton model was used to reproduce the broadband flux of the source for all the observations presented here but failed for previous observations made in April 2013. A lepto-hadronic solution was then explored to explain these earlier observational results.",
"date": "2020-07",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "639",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A42",
"id_number": "CaltechAUTHORS:20200708-065827527",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200708-065827527",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)"
},
{
"agency": "Max Planck Society"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)"
},
{
"agency": "Helmholtz Association"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Minist\u00e8re de l'Enseignement sup\u00e9rieur, de la Recherche et de l'Innovation (MESRI)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Institut National de Physique Nucl\u00e9aire et de Physique des Particules (IN2P3)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Institut National des Sciences de l'Univers (INSU)"
},
{
"agency": "Commissariat \u00e0 l'\u00c9nergie Atomique et aux \u00c9nergies Alternatives (CEA)"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Knut and Alice Wallenberg Foundation"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2016/22/M/ST9/00382"
},
{
"agency": "Department of Science and Technology (South Africa)"
},
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "University of Namibia"
},
{
"agency": "National Commission on Research, Science and Technology (Namibia)"
},
{
"agency": "Bundesministerium f\u00fcr Bildung, Wissenschaft, Forschung und Technologie (BMBF)"
},
{
"agency": "FWF Der Wissenschaftsfonds"
},
{
"agency": "Australian Research Council"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)"
},
{
"agency": "University of Amsterdam"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC02-76SF00515"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "la Caixa Banking Foundation",
"grant_number": "LCF/BQ/LI18/11630012"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
},
{
"agency": "Harvard University"
},
{
"agency": "John Templeton Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/201936900",
"primary_object": {
"basename": "1912.07273.pdf",
"url": "https://authors.library.caltech.edu/records/cvzck-kq224/files/1912.07273.pdf"
},
"related_objects": [
{
"basename": "aa36900-19.pdf",
"url": "https://authors.library.caltech.edu/records/cvzck-kq224/files/aa36900-19.pdf"
}
],
"pub_year": "2020",
"author_list": "Abdalla, H.; Adam, R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/b680s-j5d61",
"eprint_id": 104004,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:24:40",
"lastmod": "2026-03-28 21:09:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Liu-Tingting",
"name": {
"family": "Liu",
"given": "Tingting"
},
"orcid": "0000-0001-5766-4287"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "Michael"
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Blecha-L",
"name": {
"family": "Blecha",
"given": "Laura"
},
"orcid": "0000-0002-2183-1087"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Trakhtenbrot-B",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Mushotzky-R-F",
"name": {
"family": "Mushotzky",
"given": "Richard"
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ichikawa-Kohei",
"name": {
"family": "Ichikawa",
"given": "Kohei"
},
"orcid": "0000-0002-4377-903X"
},
{
"id": "Kakkad-Darshan",
"name": {
"family": "Kakkad",
"given": "Darshan"
},
"orcid": "0000-0002-2603-2639"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Powell-M-C",
"name": {
"family": "Powell",
"given": "Meredith"
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Privon-G-C",
"name": {
"family": "Privon",
"given": "George C."
},
"orcid": "0000-0003-3474-1125"
},
{
"id": "Schawinski-K",
"name": {
"family": "Schawinski",
"given": "Kevin"
},
"orcid": "0000-0001-5464-0888"
},
{
"id": "Shimizu-Thomas-Taro",
"name": {
"family": "Shimizu",
"given": "T. Taro"
},
"orcid": "0000-0002-2125-4670"
},
{
"id": "Smith-K-L",
"name": {
"family": "Smith",
"given": "Krista Lynne"
},
"orcid": "0000-0001-5785-7038"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Treister-E",
"name": {
"family": "Treister",
"given": "Ezequiel"
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Urry-C-M",
"name": {
"family": "Urry",
"given": "C. Megan"
},
"orcid": "0000-0002-0745-9792"
}
]
},
"title": "The BAT AGN Spectroscopic Survey. XVIII. Searching for Supermassive Black Hole Binaries in X-Rays",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galaxies; Surveys; X-ray sources",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 10; revised 2020 May 12; accepted 2020 May 19; published 2020 June 19. \n\nT.L., M.K., and G.C.P. thank the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611, for hosting the \"Astrophysics of Massive Black Hole Mergers: From Galaxy Mergers to the Gravitational Wave Regime\" workshop, where many stimulating discussions took place and this work was initiated. We thank the referee for a constructive report that helped improve the paper and Erin Kara for a helpful comment. \n\nT.L. is supported by NANOGrav National Science Foundation Physics Frontiers Center award No. 1430284. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. L.B. acknowledges support from National Science Foundation grant AST-1715413. C.R. acknowledges support from the CONICYT+PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080 and Fondecyt Iniciacion grant 11190831. K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). E.T. acknowledges support from CONICYT-Chile grants Basal-CATA AFB-170002, FONDECYT Regular 1160999 and 1190818, and Anillo de Ciencia y Tecnologia ACT1720033. G.C.P. acknowledges support from the University of Florida. \n\nThis research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. We acknowledge the use of public data from the Swift data archive. \n\nFacility: Swift(BAT) - Swift Gamma-Ray Burst Mission.\n\nPublished - Liu_2020_ApJ_896_122.pdf
Accepted Version - 1912.02837.pdf
",
"abstract": "Theory predicts that a supermassive black hole binary (SMBHB) could be observed as a luminous active galactic nucleus (AGN) that periodically varies on the order of its orbital timescale. In X-rays, periodic variations could be caused by mechanisms including relativistic Doppler boosting and shocks. Here we present the first systematic search for periodic AGNs using 941 hard X-ray light curves (14\u2013195 keV) from the first 105 months of the Swift Burst Alert Telescope (BAT) survey (2004\u20132013). We do not find evidence for periodic AGNs in Swift-BAT, including the previously reported SMBHB candidate MCG+11\u221211\u2212032. We find that the null detection is consistent with the combination of the upper-limit binary population in AGNs in our adopted model, their expected periodic variability amplitudes, and the BAT survey characteristics. We have also investigated the detectability of SMBHBs against normal AGN X-ray variability in the context of the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) survey. Under our assumptions of a binary population and the periodic signals they produce, which have long periods of hundreds of days, up to 13% true periodic binaries can be robustly distinguished from normal variable AGNs with the ideal uniform sampling. However, we demonstrate that realistic eROSITA sampling is likely to be insensitive to long-period binaries because longer observing gaps reduce their detectability. In contrast, large observing gaps do not diminish the prospect of detecting binaries of short, few-day periods, as 19% can be successfully recovered, the vast majority of which can be identified by the first half of the survey.",
"date": "2020-06-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "896",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 122",
"id_number": "CaltechAUTHORS:20200624-104212632",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200624-104212632",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "PHY-1607611"
},
{
"agency": "NSF",
"grant_number": "PHY-1430284"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "NSF",
"grant_number": "AST-1715413"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "2017 PAI77170080"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "11190831"
},
{
"agency": "National Research Foundation of Korea",
"grant_number": "NRF-2020R1C1C1005462"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1160999"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1190818"
},
{
"agency": "Anillo de Ciencia y Tecnologia",
"grant_number": "ACT1720033"
},
{
"agency": "University of Florida"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab952d",
"primary_object": {
"basename": "1912.02837.pdf",
"url": "https://authors.library.caltech.edu/records/b680s-j5d61/files/1912.02837.pdf"
},
"related_objects": [
{
"basename": "Liu_2020_ApJ_896_122.pdf",
"url": "https://authors.library.caltech.edu/records/b680s-j5d61/files/Liu_2020_ApJ_896_122.pdf"
}
],
"pub_year": "2020",
"author_list": "Liu, Tingting; Koss, Michael; et al."
},
{
"id": "https://authors.library.caltech.edu/records/k9t1z-wqq71",
"eprint_id": 103777,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:20:42",
"lastmod": "2026-03-30 08:40:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kourkchi-E",
"name": {
"family": "Kourkchi",
"given": "Ehsan"
},
"orcid": "0000-0002-5514-3354"
},
{
"id": "Tully-R-B",
"name": {
"family": "Tully",
"given": "R. Brent"
},
"orcid": "0000-0002-9291-1981"
},
{
"id": "Anand-Gagandeep-S",
"name": {
"family": "Anand",
"given": "Gagandeep S."
},
"orcid": "0000-0002-5259-2314"
},
{
"id": "Courtois-H-M",
"name": {
"family": "Courtois",
"given": "H\u00e9l\u00e8ne M."
},
"orcid": "0000-0003-0509-1776"
},
{
"id": "Dupuy-A",
"name": {
"family": "Dupuy",
"given": "Alexandra"
}
},
{
"id": "Neill-J-D",
"name": {
"family": "Neill",
"given": "James D."
},
"orcid": "0000-0002-0466-1119"
},
{
"id": "Rizzi-L",
"name": {
"family": "Rizzi",
"given": "Luca"
},
"orcid": "0000-0003-0882-2327"
},
{
"id": "Seibert-M",
"name": {
"family": "Seibert",
"given": "Mark"
},
"orcid": "0000-0002-1143-5515"
}
]
},
"title": "Cosmicflows-4: The Calibration of Optical and Infrared Tully\u2013Fisher Relations",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Distance measure; Galaxy distances; Galaxy photometry; H I line emission; Spiral galaxies; Inclination; Galaxy structure; Large-scale structure of the universe",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2020 February 4; revised 2020 April 9; accepted 2020 April 29; published 2020 June 8. \n\nWe are pleased to acknowledge the citizen participation in scientific research of undergraduate students at the University of Hawaii; members of amateur astronomy clubs in France at the Plan\u00e9tarium de Vaulx-en-Velin, Association Clair d'\u00e9toiles et Brin d'jardin, Soci\u00e9t\u00e9 astronomique de Lyon, Club d'astronomie Lyon Amp\u00e8re, Club d'astronomie des monts du lyonnais, and Club d'astronomie de Dijon; and friends who helped us with measuring inclinations of spiral galaxies in our sample.\n\nSupport for E.K. and R.B.T. was provided by NASA through grant No. 88NSSC18K0424 and for G.A. and R.B.T. through grants from the Space Telescope Science Institute. H.C. acknowledges support from Institut Universitaire de France.\n\nThis research has made use of the NASA/IPAC Extragalactic Database, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.\n\nPublished - Kourkchi_2020_ApJ_896_3.pdf
Accepted Version - 2004.14499.pdf
",
"abstract": "This study is a part of the Cosmicflows-4 project with the aim of measuring the distances of more than ~10,000 spiral galaxies in the local universe up to ~15,000 km s\u207b\u00b9. New H i line width information has come primarily from the Arecibo Legacy Fast ALFA Survey. Photometry of our sample galaxies has been carried out in optical (SDSS u, g, r, i, and z) and infrared (WISE W1 and W2) bands. Inclinations have been determined using an online graphical interface accessible to a collaboration of citizen scientists. Galaxy distances are measured based on the correlation between the rotation rate of spirals and their absolute luminosity, known as the Tully\u2013Fisher relation (TFR). In this study, we present the calibration of the TFR using a subsample of ~600 spirals located in 20 galaxy clusters. Correlations among such observables as color, surface brightness, and relative H i content are explored in an attempt to reduce the scatter about the TFR with the goal of obtaining more accurate distances. A preliminary determination of the Hubble constant from the distances and velocities of the calibrator clusters is H 0 = 76.0 \u00b1 1.1(stat.) \u00b1 2.3(sys.) km s\u207b\u00b9 Mpc\u207b\u00b9.",
"date": "2020-06-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "896",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 3",
"id_number": "CaltechAUTHORS:20200608-141840236",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200608-141840236",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "88NSSC18K0424"
},
{
"agency": "Space Telescope Science Institute"
},
{
"agency": "Institut Universitaire de France (IUF)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab901c",
"primary_object": {
"basename": "2004.14499.pdf",
"url": "https://authors.library.caltech.edu/records/k9t1z-wqq71/files/2004.14499.pdf"
},
"related_objects": [
{
"basename": "Kourkchi_2020_ApJ_896_3.pdf",
"url": "https://authors.library.caltech.edu/records/k9t1z-wqq71/files/Kourkchi_2020_ApJ_896_3.pdf"
}
],
"pub_year": "2020",
"author_list": "Kourkchi, Ehsan; Tully, R. Brent; et al."
},
{
"id": "https://authors.library.caltech.edu/records/76db7-chf58",
"eprint_id": 103720,
"eprint_status": "archive",
"datestamp": "2023-08-19 21:47:11",
"lastmod": "2026-03-30 07:06:19",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Makhathini-S",
"name": {
"family": "Makhathini",
"given": "Sphesihle"
}
},
{
"id": "Mooley-Kunal-Prakash",
"name": {
"family": "Mooley",
"given": "Kunal P."
},
"orcid": "0000-0002-2557-5180"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"name": {
"family": "Hotokezaka",
"given": "Kenta"
},
"orcid": "0000-0002-2502-3730"
},
{
"name": {
"family": "Nayana",
"given": "A. J."
}
},
{
"name": {
"family": "Intema",
"given": "Huib T."
},
"orcid": "0000-0002-5880-2730"
},
{
"name": {
"family": "Dobie",
"given": "Dougal"
},
"orcid": "0000-0003-0699-7019"
},
{
"name": {
"family": "Lenc",
"given": "E."
},
"orcid": "0000-0002-9994-1593"
},
{
"name": {
"family": "Perley",
"given": "Daniel A."
},
"orcid": "0000-0001-8472-1996"
},
{
"id": "Fremling-C",
"name": {
"family": "Fremling",
"given": "Christoffer"
},
"orcid": "0000-0002-4223-103X"
},
{
"name": {
"family": "Moldon",
"given": "Javier"
}
},
{
"name": {
"family": "Lazzati",
"given": "Davide"
},
"orcid": "0000-0002-9190-662X"
},
{
"name": {
"family": "Kaplan",
"given": "David L."
},
"orcid": "0000-0001-6295-2881"
},
{
"name": {
"family": "Balasubramanian",
"given": "Arvind"
}
},
{
"name": {
"family": "Brown",
"given": "Ian"
}
},
{
"name": {
"family": "Carbone",
"given": "Dario"
},
"orcid": "0000-0002-6575-4642"
},
{
"name": {
"family": "Chandra",
"given": "Poonam"
},
"orcid": "0000-0002-0844-6563"
},
{
"name": {
"family": "Corsi",
"given": "Alessandra"
}
},
{
"name": {
"family": "Camilo",
"given": "Fernando"
},
"orcid": "0000-0002-1873-3718"
},
{
"name": {
"family": "Deller",
"given": "Adam T."
},
"orcid": "0000-0001-9434-3837"
},
{
"name": {
"family": "Frail",
"given": "Dale A."
}
},
{
"name": {
"family": "Murphy",
"given": "Tara"
},
"orcid": "0000-0002-2686-438X"
},
{
"name": {
"family": "Murphy",
"given": "Eric J."
},
"orcid": "0000-0001-7089-7325"
},
{
"name": {
"family": "Nakar",
"given": "Ehud"
},
"orcid": "0000-0002-4534-7089"
},
{
"name": {
"family": "Smirnov",
"given": "Oleg"
}
},
{
"name": {
"family": "Beswick",
"given": "Robert"
}
},
{
"name": {
"family": "Fender",
"given": "Rob"
}
},
{
"id": "Hallinan-G",
"name": {
"family": "Hallinan",
"given": "Gregg"
},
"orcid": "0000-0002-7083-4049"
},
{
"name": {
"family": "Heywood",
"given": "Ian"
}
},
{
"id": "Kasliwal-M-M",
"name": {
"family": "Kasliwal",
"given": "Mansi M."
},
"orcid": "0000-0002-5619-4938"
},
{
"id": "Lee-Bomee",
"name": {
"family": "Lee",
"given": "Bomee"
},
"orcid": "0000-0003-1954-5046"
},
{
"id": "Lu-Wenbin",
"name": {
"family": "Lu",
"given": "Wenbin"
},
"orcid": "0000-0002-1568-7461"
},
{
"name": {
"family": "Rana",
"given": "Javed"
},
"orcid": "0000-0001-5605-1809"
},
{
"name": {
"family": "Perkins",
"given": "S. J."
}
},
{
"name": {
"family": "White",
"given": "Sarah V."
}
},
{
"name": {
"family": "Jozsa",
"given": "Gyula I."
}
},
{
"name": {
"family": "Hugo",
"given": "Benjamin"
}
},
{
"name": {
"family": "Kamphuis",
"given": "Peter"
}
}
]
},
"title": "The Panchromatic Afterglow of GW170817: The full uniform dataset, modeling, comparison with previous results and implications",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "gravitational waves - stars: neutron - radio continuum: stars - X-rays: stars - infrared: stars",
"note": "The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The authors thank the NRAO staff, especially Mark Claussen and Amy Mioduszewski, for scheduling the VLA observations. The Australia Telescope is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. We thank the staff of the GMRT that made these observations possible. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology. The authors are grateful to Schuyler van Dyk for helpful discussions. KPM is a Jansky Fellow of the National Radio Astronomy Observatory. DD is supported by an Australian Government Research Training Program Scholarship. TM acknowledges the support of the Australian Research Council through grant DP190100561. Parts of this research were conducted by the Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav), project number CE170100004. We acknowledge support by the GROWTH (Global Relay of Observatories Watching Transients Happen) project funded by the National Science Foundation PIRE (Partnership in International Research and Education) program under Grant No 1545949. DL acknowledges support from NASA grants 80NSSC18K1729 (Fermi) and NNX17AK42G (ATP), Chandra grant TM9-20002X, and NSF grant AST-1907955. This research has made use of NASA's Astrophysics Data System Bibliographic Services. CF gratefully acknowledges support of his research by the Heising-Simons Foundation. JM acknowledges financial support from the State Agency for Research of the Spanish MCIU through the \"Center of Excellence Severo Ochoa\" award to the Instituto de Astrof\u00edsica de Andaluc\u00eda (SEV-2017-0709) and from the grant RTI2018-096228-B-C31 (MICIU/FEDER, EU). DLK was supported by NSF grant AST-1816492 PK is partially supported by the BMBF project 05A17PC2 for D-MeerKAT. \n\nFacility: VLA, ATCA, uGMRT, MeerKAT, eMERLIN, HST, Chandra, XMM-Newton Software: MIRIAD (Sault et al. 1995), CASA (McMullin et al. 2007), emcee (Foreman-Mackey et al. 2013), corner (Foreman-Mackey 2016) , CARACal (Ramatsoku et al. 2020), AOFlagger (Offringa et al. 2010), WSClean (Offringa et al. 2014), CubiCal (Kenyon et al. 2018), MeqTrees (Noordam & Smirnov 2010)\n\nSubmitted - 2006.02382.pdf
",
"abstract": "We present the full panchromatic afterglow light curve data of GW170817, including new radio data as well as archival optical and X-ray data, between 0.5 and 940 days post-merger. By compiling all archival data, and reprocessing a subset of it, we have ensured that the panchromatic dataset is uniform and therefore immune to the differences in data processing or flux determination methods used by different groups. Simple power-law fits to the uniform afterglow light curve indicate a t^(0.86\u00b10.04) rise, a t^(\u22121.90\u00b10.12) decline, and a peak occurring at 155\u00b14 days. The afterglow is optically thin throughout its evolution, consistent with a single spectral index (\u22120.569\u00b10.002) across all epochs. This gives a precise and updated estimate of the electron power-law index, p=2.138\u00b10.004. By studying the diffuse X-ray emission from the host galaxy, we place a conservative upper limit on the hot ionized ISM density, <0.01 cm\u207b\u00b3, consistent with previous afterglow studies. Using the late-time afterglow data we rule out any long-lived neutron star remnant having magnetic field strength between 10^(10.4) G and 10\u00b9\u2076 G. Our fits to the afterglow data using an analytical model that includes VLBI proper motion from Mooley et al (2018), and a structured jet model that ignores the proper motion, indicates that the proper motion measurement needs to be considered while seeking an accurate estimate of the viewing angle.",
"date": "2020-06-03",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20200604-151511891",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200604-151511891",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "Department of Science and Innovation (South Africa)"
},
{
"agency": "National Radio Astronomy Observatory"
},
{
"agency": "Commonwealth Scientific and Industrial Research Organisation (CSIRO)"
},
{
"agency": "Tata Institute of Fundamental Research"
},
{
"agency": "South African Radio Astronomy Observatory (SARAO)"
},
{
"agency": "Jansky Fellowship"
},
{
"agency": "Australian Research Council",
"grant_number": "DP190100561"
},
{
"agency": "Australian Research Council",
"grant_number": "CE170100004"
},
{
"agency": "NSF",
"grant_number": "AST-1545949"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1729"
},
{
"agency": "NASA",
"grant_number": "NNX17AK42G"
},
{
"agency": "NASA",
"grant_number": "TM9-20002X"
},
{
"agency": "NSF",
"grant_number": "AST-1907955"
},
{
"agency": "Heising-Simons Foundation"
},
{
"agency": "Severo Ochoa",
"grant_number": "SEV-2017-0709"
},
{
"agency": "Ministerio de Ciencia, Innovaci\u00f3n y Universidades (MICIU)",
"grant_number": "RTI2018-096228-B-C31"
},
{
"agency": "Fondo Europeo de Desarrollo Regional (FEDER)"
},
{
"agency": "NSF",
"grant_number": "AST-1816492"
},
{
"agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)",
"grant_number": "05A17PC2"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Infrared-Processing-and-Analysis-Center-(IPAC)"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.48550/arXiv.2006.02382",
"primary_object": {
"basename": "2006.02382.pdf",
"url": "https://authors.library.caltech.edu/records/76db7-chf58/files/2006.02382.pdf"
},
"pub_year": "2020",
"author_list": "Makhathini, Sphesihle; Mooley, Kunal P.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ymny8-gpf03",
"eprint_id": 102514,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:17:09",
"lastmod": "2026-03-30 07:07:32",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah"
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Israel-Gianluca",
"name": {
"family": "Israel",
"given": "Gianluca"
},
"orcid": "0000-0001-5480-6438"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean"
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Swift Monitoring of M51: A 38 day Superorbital Period for the Pulsar ULX7 and a New Transient Ultraluminous X-Ray Source",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray point sources; X-ray transient sources; X-ray photometry; X-ray bright point; X-ray active galactic nuclei; Transient sources; Light curves; Galaxy nuclei; Active galactic nuclei",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 December 9; revised 2020 February 19; accepted 2020 March 4; published 2020 June 4. \n\nWe wish to thank the Swift PI, Brad Cenko for approving the target of opportunity requests we made to observe M51, as well as the rest of the Swift team for carrying them out. We also acknowledge the use of public data from the Swift data archive. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. The work of D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. D.J.W. acknowledges support from an STFC Ernest Rutherford Fellowship.\n\nPublished - Brightman_2020_ApJ_895_127.pdf
Submitted - 1912.04431.pdf
",
"abstract": "We present the results from a monitoring campaign made with the Neil Gehrels Swift Observatory of the M51 galaxies, which contain several variable ultraluminous X-ray sources (ULXs). The ongoing campaign started in 2018 May, and we report here on ~1.5 yr of observations. The campaign, which consists of 106 observations, has a typical cadence of 3\u20136 days, and has the goal of determining the long-term X-ray variability of the ULXs. Two of the most variable sources were ULX7 and ULX8, both of which are known to be powered by neutron stars that are exceeding their isotropic Eddington luminosities by factors of up to 100. This is further evidence that neutron-star-powered ULXs are the most variable. Our two main results are, first, that ULX7 exhibits a periodic flux modulation with a period of 38 days varying over a magnitude and a half in flux from peak to trough. Since the orbital period of the system is known to be 2 days, the modulation is superorbital, which is a near-ubiquitous property of ULX pulsars. Second, we identify a new transient ULX, M51 XT-1, the onset of which occurred during our campaign, reaching a peak luminosity of ~10\u2074\u2070 erg s\u207b\u00b9, before gradually fading over the next ~200 days until it slipped below the detection limit of our observations. Combined with the high-quality Swift/X-ray Telescope lightcurve of the transient, serendipitous observations made with Chandra and XMM-Newton provide insights into the onset and evolution of a likely super-Eddington event.",
"date": "2020-06-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "895",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 127",
"id_number": "CaltechAUTHORS:20200414-070245589",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200414-070245589",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab7e2a",
"primary_object": {
"basename": "1912.04431.pdf",
"url": "https://authors.library.caltech.edu/records/ymny8-gpf03/files/1912.04431.pdf"
},
"related_objects": [
{
"basename": "Brightman_2020_ApJ_895_127.pdf",
"url": "https://authors.library.caltech.edu/records/ymny8-gpf03/files/Brightman_2020_ApJ_895_127.pdf"
}
],
"pub_year": "2020",
"author_list": "Brightman, Murray; Earnshaw, Hannah; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z34b9-ecz48",
"eprint_id": 102512,
"eprint_status": "archive",
"datestamp": "2023-08-19 21:35:24",
"lastmod": "2026-03-30 13:55:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Nowak-M-A",
"name": {
"family": "Nowak",
"given": "M."
},
"orcid": "0000-0001-6923-1315"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Sathyaprakash-Rajath",
"name": {
"family": "Sathyaprakash",
"given": "R."
},
"orcid": "0000-0002-5254-3969"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Soria-Roberto",
"name": {
"family": "Soria",
"given": "R."
},
"orcid": "0000-0002-4622-796X"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Canizares-C-R",
"name": {
"family": "Canizares",
"given": "C. R."
}
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Tao-Lian",
"name": {
"family": "Tao",
"given": "L."
}
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "N."
}
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kosec-P",
"name": {
"family": "Kosec",
"given": "P."
}
}
]
},
"title": "The unusual broad-band X-ray spectral variability of NGC\u20091313 X-1 seen with XMM\u2013Newton, Chandra, and NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-rays: binaries \u2013 X-rays: individual: NGC1313 X-1",
"note": "\u00a9 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2020 April 20. Received 2020 April 20; in original form 2019 November 20. Published: 26 April 2020. \n\nThe authors would like to thank the reviewer for their positive and thorough feedback, which helped to improve the final version of this manuscript. DJW and MJM acknowledge support from Science and Technology Facilities Council (STFC) Ernest Rutherford Fellowships. CP and FF acknowledge support from European Space Agency (ESA) Research Fellowships. HPE acknowledges support under National Aeronautics and Space Administration (NASA) contract NNG08FD60C. TPR was funded as part of the STFC consolidated grant ST/K000861/1. NW acknowledges support from Centre National d'Etudes Spatiales (CNES) for this work. CRC and MN acknowledge support from the Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 to the Massachusetts Institute of Technology (MIT), which is in turn supported by NASA under contract NAS8-03060 for the Chandra X-ray Center (CXC). This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA Jet Propulsion Laboratory (JPL), and has utilized the NUSTARDAS software package, jointly developed by the Space Science Data Centre (SSDC; Italy) and Caltech (USA). This research has also made use of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States.\n\nPublished - staa1129.pdf
Submitted - 1911.09622.pdf
",
"abstract": "We present results from the major coordinated X-ray observing programme on the ULX NGC\u20091313 X-1 performed in 2017, combining XMM\u2013Newton, Chandra, and NuSTAR, focusing on the evolution of the broad-band (\u223c0.3\u201330.0\u2009keV) continuum emission. Clear and unusual spectral variability is observed, but this is markedly suppressed above \u223c10\u201315\u2009keV, qualitatively similar to the ULX Holmberg\u2009IX X-1. We model the multi-epoch data with two-component accretion disc models designed to approximate super-Eddington accretion, allowing for both a black hole and a neutron star accretor. With regards to the hotter disc component, the data trace out two distinct tracks in the luminosity\u2013temperature plane, with larger emitting radii and lower temperatures seen at higher observed fluxes. Despite this apparent anticorrelation, each of these tracks individually shows a positive luminosity\u2013temperature relation. Both are broadly consistent with L \u221d T\u2074, as expected for blackbody emission with a constant area, and also with L \u221d T\u00b2, as may be expected for an advection-dominated disc around a black hole. We consider a variety of possibilities for this unusual behaviour. Scenarios in which the innermost flow is suddenly blocked from view by outer regions of the super-Eddington disc/wind can explain the luminosity\u2013temperature behaviour, but are difficult to reconcile with the lack of strong variability at higher energies, assuming this emission arises from the most compact regions. Instead, we may be seeing evidence for further radial stratification of the accretion flow than is included in the simple models considered, with a combination of winds and advection resulting in the suppressed high-energy variability.",
"date": "2020-06",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "494",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "6012-6029",
"id_number": "CaltechAUTHORS:20200413-153610462",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200413-153610462",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K000861/1"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "Smithsonian Astrophysical Observatory",
"grant_number": "SV3-73016"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa1129",
"primary_object": {
"basename": "1911.09622.pdf",
"url": "https://authors.library.caltech.edu/records/z34b9-ecz48/files/1911.09622.pdf"
},
"related_objects": [
{
"basename": "staa1129.pdf",
"url": "https://authors.library.caltech.edu/records/z34b9-ecz48/files/staa1129.pdf"
}
],
"pub_year": "2020",
"author_list": "Walton, D. J.; Pinto, C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5xfp6-sc356",
"eprint_id": 96512,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:06:33",
"lastmod": "2026-03-30 09:01:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rodr\u00edguez-Castillo-G-A",
"name": {
"family": "Rodr\u00edguez Castillo",
"given": "G. A."
}
},
{
"id": "Israel-GianLuca",
"name": {
"family": "Israel",
"given": "G. L."
},
"orcid": "0000-0001-5480-6438"
},
{
"id": "Belfiore-A",
"name": {
"family": "Belfiore",
"given": "A."
}
},
{
"id": "Bernardini-Federico",
"name": {
"family": "Bernardini",
"given": "F."
}
},
{
"id": "Esposito-P",
"name": {
"family": "Esposito",
"given": "P."
},
"orcid": "0000-0003-4849-5092"
},
{
"id": "Pintore-F",
"name": {
"family": "Pintore",
"given": "F."
}
},
{
"id": "De-Luca-A",
"name": {
"family": "De Luca",
"given": "A."
}
},
{
"id": "Papitto-A",
"name": {
"family": "Papitto",
"given": "A."
}
},
{
"id": "Stella-L",
"name": {
"family": "Stella",
"given": "L."
}
},
{
"id": "Tiengo-A",
"name": {
"family": "Tiengo",
"given": "A."
},
"orcid": "0000-0002-6038-1090"
},
{
"id": "Zampieri-L",
"name": {
"family": "Zampieri",
"given": "L."
}
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Casella-P",
"name": {
"family": "Casella",
"given": "P."
}
},
{
"id": "D'Agostino-D",
"name": {
"family": "D'Agostino",
"given": "D."
}
},
{
"id": "Dall'Osso-S",
"name": {
"family": "Dall'Osso",
"given": "S."
}
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Haberl-F",
"name": {
"family": "Haberl",
"given": "F."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Mapelli-M",
"name": {
"family": "Mapelli",
"given": "M."
}
},
{
"id": "Marelli-M",
"name": {
"family": "Marelli",
"given": "M."
}
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Salvaterra-R",
"name": {
"family": "Salvaterra",
"given": "R."
}
},
{
"id": "Turolla-R",
"name": {
"family": "Turolla",
"given": "R."
}
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Wolter-A",
"name": {
"family": "Wolter",
"given": "A."
}
}
]
},
"title": "Discovery of a 2.8 s Pulsar in a 2 Day Orbit High-mass X-Ray Binary Powering the Ultraluminous X-Ray Source ULX-7 in M51",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Neutron stars; Stellar accretion; X-ray sources; Stellar magnetic fields; X-ray binary stars; Pulsars",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 June 11; revised 2020 April 9; accepted 2020 April 15; published 2020 May 26. \n\nWe thank Dr. Norbert Schartel for granting DPS XMM-Newton time. The scientific results reported in this article are based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and NASA. G.R. acknowledges the support of high-performance computing resources awarded by CINECA (MARCONI and GALILEO), under the ISCRA initiative and the INAF\u2013CIENCA MoU, and the computing centers of INAF\u2013Osservatorio Astronomico di Trieste and Osservatorio Astrofisico di Catania, under the coordination of the CHIPP project, for the availability of computing resources and support. This work has also made use of observations made with the NASA/ESA Hubble Space Telescope and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA), and the Canadian Astronomy Data Centre (CADC/NRC/CSA). This work has also made use of data from the ESA mission Gaia, processed by the Gaia Data Processing and Analysis Consortium (DPAC). We acknowledge funding in the framework of the project ULTraS ASI\u2013INAF contract No. 2017-14-H.0, project ASI\u2013INAF contract I/037/12/0, and PRIN grant 2017LJ39LM. F.B. is funded by the European Unions Horizon 2020 research and innovation program under Marie Sk\u0142odowska Curie grant agreement No. 664931. F.F. and C.P. acknowledge support from ESA Research Fellowships. This research was supported by high-performance computing resources at New York University Abu Dhabi. H.P.E. acknowledges support under NASA contract NNG08FD60C. T.P.R. acknowledges support from STFC as part of consolidated grant ST/K000861/1. We thank the anonymous referee for the helpful comments on the manuscript. A.P. acknowledges financial support from grants ASI/INAF I/037/12/0, ASI/INAF 2017-14-H.0 (PI: Belloni) and from INAF \"Sostegno allaricerca scientifica main streams dell'INAF,\" Presidential Decree 43/2018 (PI: Belloni).\n\nPublished - Rodr\u00edguez_Castillo_2020_ApJ_895_60.pdf
Submitted - 1906.04791.pdf
",
"abstract": "We discovered 2.8 s pulsations in the X-ray emission of the ultraluminous X-ray source (ULX) M51 ULX-7 within the UNSEeN project, which was designed to hunt for new pulsating ULXs (PULXs) with XMM-Newton. The pulse shape is sinusoidal, and large variations of its amplitude were observed even within single exposures (pulsed fraction from less than 5% to 20%). Source M51 ULX-7 is variable, generally observed at an X-ray luminosity between 10\u00b3\u2079 and 10\u2074\u2070 erg s\u207b\u00b9, located in the outskirts of the spiral galaxy M51a at a distance of 8.6 Mpc. According to our analysis, the X-ray pulsar orbits in a 2 day binary with a projected semimajor axis a_X sin I \u2243 28 lt-s. For a neutron star (NS) of 1.4 M\u2299, this implies a lower limit on the companion mass of 8 M\u2299, placing the system hosting M51 ULX-7 in the high-mass X-ray binary class. The barycentric pulse period decreased by 0.4 ms in the 31 days spanned by our 2018 May\u2013June observations, corresponding to a spin-up rate \u1e56 \u2243\u22121.5\u00d710\u207b\u00b9\u2070s s\u207b\u00b9. In an archival 2005 XMM-Newton exposure, we measured a spin period of ~3.3 s, indicating a secular spin-up of \u1e56_(sec) \u2243 \u221210\u207b\u2079s s\u207b\u00b9, a value in the range of other known PULXs. Our findings suggest that the system consists of a massive donor, possibly an OB giant or supergiant, and a moderately magnetic (dipole field component in the range 10\u00b9\u00b2 G \u2272 B_(dip) \u227210\u00b9\u00b3 G) accreting NS with weakly beamed emission (1/12 \u2272 b \u2272 1/4).",
"date": "2020-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "895",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 60",
"id_number": "CaltechAUTHORS:20190619-080458696",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190619-080458696",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "ESA Member States"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "2017LJ39LM"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "664931"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K000861/1"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "43/2018"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab8a44",
"primary_object": {
"basename": "1906.04791.pdf",
"url": "https://authors.library.caltech.edu/records/5xfp6-sc356/files/1906.04791.pdf"
},
"related_objects": [
{
"basename": "Rodr\u00edguez_Castillo_2020_ApJ_895_60.pdf",
"url": "https://authors.library.caltech.edu/records/5xfp6-sc356/files/Rodr\u00edguez_Castillo_2020_ApJ_895_60.pdf"
}
],
"pub_year": "2020",
"author_list": "Rodr\u00edguez Castillo, G. A.; Israel, G. L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/agkm8-m5742",
"eprint_id": 103422,
"eprint_status": "archive",
"datestamp": "2023-08-22 05:07:21",
"lastmod": "2026-03-29 14:49:48",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-R-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Cackett-E-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Bult-P-M",
"name": {
"family": "Bult",
"given": "P. M."
}
},
{
"id": "Strohmayer-T-E",
"name": {
"family": "Strohmayer",
"given": "T. E."
},
"orcid": "0000-0001-7681-5845"
},
{
"id": "Guillot-S",
"name": {
"family": "Guillot",
"given": "S."
},
"orcid": "0000-0002-6449-106X"
},
{
"id": "Jaisawal-G-K",
"name": {
"family": "Jaisawal",
"given": "G. K."
},
"orcid": "0000-0002-6789-2723"
},
{
"id": "Malacaria-C",
"name": {
"family": "Malacaria",
"given": "C."
},
"orcid": "0000-0002-0380-0041"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Markwardt-C-B",
"name": {
"family": "Markwardt",
"given": "C. B."
},
"orcid": "0000-0001-9803-3879"
}
]
},
"title": "NICER\u2013NuSTAR Observations of the Neutron Star Low-mass X-Ray Binary 4U 1735\u201344",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Neutron stars; Low-mass x-ray binary stars",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2020 February 21; revised 2020 April 4; accepted 2020 April 14; published 2020 May 22. \n\nSupport for this work was provided by NASA through the NASA Hubble Fellowship grant #HST-HF2-51440.001 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. J.A.G. acknowledges support from NASA grant 80NSSC19K1020 and from the Alexander von Humboldt Foundation. E.M.C. gratefully acknowledges support through NSF CAREER award number AST-1351222. C.M. is supported by an appointment to the NASA Postdoctoral Program at the MSFC, administered by USRA. \n\nFacilities: ADS - , HEASARC - , NICER - , NuSTAR. - \n\nSoftware: heasoft (v6.26.1), nustardas (v1.8.0), nicerdas (2019-06-19_V006a), xspec (v12.10.1).\n\nPublished - Ludlam_2020_ApJ_895_45.pdf
Accepted Version - 2004.06723.pdf
",
"abstract": "We report on the first simultaneous Neutron Star Interior Composition Explore (NICER) and Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the neutron star (NS) low-mass X-ray binary 4U 1735\u221244, obtained in 2018 August. The source was at a luminosity of ~1.8 (D/5.6 kpc) \u00b2 \u00d7 10\u00b3\u2077 erg s\u207b\u00b9 in the 0.4\u201330 keV band. We account for the continuum emission with two different continuum descriptions that have been used to model the source previously. Despite the choice in continuum model, the combined passband reveals a broad Fe K line indicative of reflection in the spectrum. In order to account for the reflection spectrum we utilize a modified version of the reflection model RELXILL that is tailored for thermal emission from accreting NSs. Alternatively, we also use the reflection convolution model of RFXCONV to model the reflected emission that would arise from a Comptonized thermal component for comparison. We determine that the innermost region of the accretion disk extends close to the innermost stable circular orbit (R_(ISCO)) at the 90% confidence level regardless of reflection model. Moreover, the current flux calibration of NICER is within 5% of the NuSTAR/FPMA(B).",
"date": "2020-05-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "895",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 45",
"id_number": "CaltechAUTHORS:20200522-131436417",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200522-131436417",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51440.001"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1020"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NSF",
"grant_number": "AST-1351222"
},
{
"agency": "NASA Postdoctoral Program"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ab89a6",
"primary_object": {
"basename": "2004.06723.pdf",
"url": "https://authors.library.caltech.edu/records/agkm8-m5742/files/2004.06723.pdf"
},
"related_objects": [
{
"basename": "Ludlam_2020_ApJ_895_45.pdf",
"url": "https://authors.library.caltech.edu/records/agkm8-m5742/files/Ludlam_2020_ApJ_895_45.pdf"
}
],
"pub_year": "2020",
"author_list": "Ludlam, R. M.; Cackett, E. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/v2mas-3we29",
"eprint_id": 103715,
"eprint_status": "archive",
"datestamp": "2023-08-19 21:20:56",
"lastmod": "2026-03-30 06:25:04",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "Sean"
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "NuSTAR low energy effective area correction due to thermal blanket tear",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "space vehicles: instruments",
"note": "This work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacility: NuSTAR\n\nThis document serves as a technical note for the NuSTAR CALDB version 20200429. The CADLB release is the first in a two parts made to address the problem described in the paper. The paper will be updated with the second release, and will be submitted to a journal after the final release.\n\nSubmitted - 2005.00569.pdf
",
"abstract": "A rip in the MLI at the exit aperture of OMA, the NuSTAR optic aligned with detector focal plane module FPMA, has resulted in an increased photon flux through OMA that has manifested itself as a low energy excess. Overall, the MLI coverage has decreased by 10%, but there is an additional time-varying component, which occasionally causes the opening to increase by up to 20%. We address the problem with a calibration update, and in this paper, we describe the attributes of the problem, the implications it has on data analysis, and the solution.",
"date": "2020-05-01",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20200604-151455025",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200604-151455025",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.48550/arXiv.2005.00569",
"primary_object": {
"basename": "2005.00569.pdf",
"url": "https://authors.library.caltech.edu/records/v2mas-3we29/files/2005.00569.pdf"
},
"pub_year": "2020",
"author_list": "Madsen, Kristin K.; Grefenstette, Brian W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/k141q-vws72",
"eprint_id": 96609,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:41:55",
"lastmod": "2026-03-29 20:04:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lopez-L-A",
"name": {
"family": "Lopez",
"given": "Laura A."
},
"orcid": "0000-0002-1790-3148"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Auchettl-K",
"name": {
"family": "Auchettl",
"given": "Katie"
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Castro-D",
"name": {
"family": "Castro",
"given": "Daniel"
}
}
]
},
"title": "Evidence of Particle Acceleration in the Superbubble 30 Doradus C with NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Shocks; X-ray astronomy; Interstellar medium; Superbubbles",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2018 November 30; revised 2020 March 19; accepted 2020 March 21; published 2020 April 24. \n\nWe thank Parviz Ghavamian, Maria Haupt, and Steve Reynolds for useful discussions and Annie Hughes for sharing the ATCA and Parkes survey data of the LMC. Additionally, we thank Daniel Wik for assistance with nuskybgd. We also acknowledge the continued work of the astronomical community contributing to AstroLib. Our work was supported under NASA contract NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). Support for this work was provided by National Aeronautics and Space Administration through Chandra Award Number G08\u201319062X and through Smithsonian Astrophysical Observatory contract SV3\u201373016 to MIT issued by the Chandra X-ray Observatory Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA under contract NAS8\u201303060. \n\nSoftware: CIAO (v4.7; Fruscione et al. 2006), XSPEC (v12.9.0; Arnaud 1996), ftools (Blackburn 1995), NuSTAR Data Analysis Software (v1.8.0), XMM-NewtonSAS (v15.0.0; Gabriel et al. 2004).\n\nPublished - Lopez_2020_ApJ_893_144.pdf
Submitted - 1811.12416.pdf
",
"abstract": "We present evidence of diffuse, non-thermal X-ray emission from the superbubble 30 Doradus C (30 Dor C) using hard X-ray images and spectra from NuSTAR observations. For this analysis, we utilize data from a 200 ks targeted observation of 30 Dor C as well as 2.8 Ms of serendipitous off-axis observations from the monitoring of nearby SN 1987A. The complete shell of 30 Dor C is detected up to 20 keV, and the young supernova remnant MCSNR J0536\u22126913 in the southeast of 30 Dor C is not detected above 8 keV. Additionally, six point sources identified in previous Chandra and XMM-Newton investigations have hard X-ray emission coincident with their locations. Joint spectral fits to the NuSTAR and XMM-Newton spectra across the 30 Dor C shell confirm the non-thermal nature of the diffuse emission. Given the best-fit rolloff frequencies of the X-ray spectra, we find maximum electron energies of \u224870\u2013110 TeV (assuming a B-field strength of 4 \u03bcG), suggesting 30 Dor C is accelerating particles. Particles are either accelerated via diffusive shock acceleration at locations where the shocks have not stalled behind the H\u03b1 shell, or cosmic-rays are accelerated through repeated acceleration of low-energy particles via turbulence and magnetohydrodynamic waves in the bubble's interior.",
"date": "2020-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "893",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 144",
"id_number": "CaltechAUTHORS:20190620-154339961",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190620-154339961",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "G08-19062X"
},
{
"agency": "Smithsonian Astrophysical Observatory",
"grant_number": "SV3-73016"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1811.12416",
"primary_object": {
"basename": "1811.12416.pdf",
"url": "https://authors.library.caltech.edu/records/k141q-vws72/files/1811.12416.pdf"
},
"related_objects": [
{
"basename": "Lopez_2020_ApJ_893_144.pdf",
"url": "https://authors.library.caltech.edu/records/k141q-vws72/files/Lopez_2020_ApJ_893_144.pdf"
}
],
"pub_year": "2020",
"author_list": "Lopez, Laura A.; Grefenstette, Brian W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8wybd-rmk72",
"eprint_id": 102715,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:43:16",
"lastmod": "2026-03-30 14:31:54",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cooper-Kristopher",
"name": {
"family": "Cooper",
"given": "Kristopher"
},
"orcid": "0000-0001-8589-3378"
},
{
"id": "Hannah-Iain-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Glesener-Lindsay",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Krucker-S\u00e4m",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
},
"orcid": "0000-0002-2002-9180"
},
{
"id": "Hudson-Hugh-S",
"name": {
"family": "Hudson",
"given": "Hugh S."
},
"orcid": "0000-0001-5685-1283"
},
{
"id": "White-Stephen-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
},
{
"id": "Smith-David-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
}
]
},
"title": "NuSTAR Observation of a Minuscule Microflare in a Solar Active Region",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar activity; Solar corona; Solar flares; Solar x-ray flares",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2020 March 17; revised 2020 April 4; accepted 2020 April 7; published 2020 April 22. \n\nThis Letter made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, funded by the National Aeronautics and Space Administration. These observations were supported through the NuSTAR Guest Observer program (NASA grant 80NSSC18K1744). This research has made use of SunPy v1.0.6, an open-source and free community-developed solar data analysis Python package (SunPy Community et al. 2015). This research also made use of HEASoft (a unified release of FTOOLS and XANADU software packages) and NuSTAR Data Analysis Software (NuSTARDAS). This Letter made use of the SolarSoft IDL distribution (SSW) from the IDL Astronomy Library. \n\nK.C. is supported by a Royal Society Research Fellows Enhancement Award and I.G.H is supported by a Royal Society University Fellowship.\n\nPublished - Cooper_2020_ApJL_893_L40.pdf
Accepted Version - 2004.11176.pdf
",
"abstract": "We present X-ray imaging spectroscopy of one of the weakest active region (AR) microflares ever studied. The microflare occurred at ~11:04 UT on 2018 September 9 and we studied it using the Nuclear Spectroscopic Telescope ARray (NuSTAR) and the Solar Dynamic Observatory's Atmospheric Imaging Assembly (SDO/AIA). The microflare is observed clearly in 2.5\u20137 keV with NuSTAR and in Fe XVIII emission derived from the hotter component of the 94 \u00c5 SDO/AIA channel. We estimate the event to be three orders of magnitude lower than a GOES A class microflare with an energy of 1.1 \u00d7 10\u00b2\u2076 erg. It reaches temperatures of 6.7 MK with an emission measure of 8.0 \u00d7 10\u2074\u00b3 cm\u207b\u00b3. Non-thermal emission is not detected but we instead determine upper limits to such emission. We present the lowest thermal energy estimate for an AR microflare in literature, which is at the lower limits of what is still considered an X-ray microflare.",
"date": "2020-04-20",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "893",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L40",
"id_number": "CaltechAUTHORS:20200422-095631058",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200422-095631058",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1744"
},
{
"agency": "Royal Society"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/2041-8213/ab873e",
"pmcid": "PMC8780508",
"primary_object": {
"basename": "2004.11176.pdf",
"url": "https://authors.library.caltech.edu/records/8wybd-rmk72/files/2004.11176.pdf"
},
"related_objects": [
{
"basename": "Cooper_2020_ApJL_893_L40.pdf",
"url": "https://authors.library.caltech.edu/records/8wybd-rmk72/files/Cooper_2020_ApJL_893_L40.pdf"
}
],
"pub_year": "2020",
"author_list": "Cooper, Kristopher; Hannah, Iain G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/wxgz8-9qj27",
"eprint_id": 102511,
"eprint_status": "archive",
"datestamp": "2023-08-19 20:55:56",
"lastmod": "2026-03-28 22:23:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Hare-J",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Evidence for Disk Truncation at Low Accretion States of the Black Hole Binary MAXI J1820+070 Observed by NuSTAR and XMM-Newton",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion, Black hole physics, X-ray binary stars, X-ray transient sources",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2020 January 26; revised 2020 March 2; accepted 2020 March 3; published 2020 April 14. \n\nWe thank the referee for helpful comments that improved the paper. We thank Norbert Schartel for approving the XMM-Newton DDT observation and the XMM-Newton SOC for prompt scheduling of the observation. J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the USRA through a contract with NASA. D.J.W. acknowledge support from an STFC Ernest Rutherford Fellowship. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations.\n\nPublished - Xu_2020_ApJ_893_42.pdf
Submitted - 2003.01778.pdf
",
"abstract": "We present results from NuSTAR and XMM-Newton observations of the new black hole X-ray binary MAXI J1820+070 at low accretion rates (below 1% of the Eddington luminosity). We detect a narrow Fe K\u03b1 emission line, in contrast to the broad and asymmetric Fe K\u03b1 line profiles commonly present in black hole binaries at high accretion rates. The narrow line, with weak relativistic broadening, indicates that the Fe K\u03b1 line is produced at a large disk radius. Fitting with disk reflection models assuming standard disk emissivity finds a large disk truncation radius (a few tens to a few hundreds of gravitational radii, depending on the disk inclination). In addition, we detect a quasi-periodic oscillation (QPO) varying in frequency between 11.6 \u00b1 0.2 mHz and 2.8 \u00b1 0.1 mHz. The very low QPO frequencies suggest a large size for the optically thin Comptonization region according to the Lense\u2013Thirring precession model, supporting that the accretion disk recedes from the innermost stable circular orbit and is replaced by advection-dominated accretion flow at low accretion rates. We also discuss the possibility of an alternative accretion geometry that the narrow Fe K\u03b1 line is produced by a lamppost corona with a large height illuminating the disk.",
"date": "2020-04-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "893",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 42",
"id_number": "CaltechAUTHORS:20200413-152859389",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200413-152859389",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab7cdb",
"primary_object": {
"basename": "2003.01778.pdf",
"url": "https://authors.library.caltech.edu/records/wxgz8-9qj27/files/2003.01778.pdf"
},
"related_objects": [
{
"basename": "Xu_2020_ApJ_893_42.pdf",
"url": "https://authors.library.caltech.edu/records/wxgz8-9qj27/files/Xu_2020_ApJ_893_42.pdf"
}
],
"pub_year": "2020",
"author_list": "Xu, Yanjun; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/sm3vt-p5e61",
"eprint_id": 102508,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:38:57",
"lastmod": "2026-03-29 21:11:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Hare-J",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
}
]
},
"title": "Studying the Reflection Spectra of the New Black Hole X-Ray Binary Candidate MAXI J1631\u2212479 Observed by NuSTAR: A Variable Broad Iron Line Profile",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; black hole physics; X-ray binary stars; X-ray transient sources",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 August 26; revised 2020 March 5; accepted 2020 March 6; published 2020 April 13. \n\nWe thank the referee for the constructive comments that improved this paper. D.J.W. acknowledges support from an STFC Ernest Rutherford fellowship. J.A.G. acknowledges support from NASA grant NNX17AJ65G and from the Alexander von Humboldt Foundation. J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the USRA through a contract with NASA. M.L.P. is supported by the European Space Agency (ESA) Research Fellowship. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has also made use of MAXI data provided by RIKEN, JAXA, and the MAXI team.\n\nPublished - Xu_2020_ApJ_893_30.pdf
Accepted Version - 2003.03465.pdf
",
"abstract": "We present results from the Nuclear Spectroscopic Telescope Array observations of the new black hole X-ray binary candidate MAXI J1631\u2013479 at two epochs during its 2018\u20132019 outburst, which caught the source in a disk dominant state and a power-law dominant state. Strong relativistic disk reflection features are clearly detected, displaying significant variations in the shape and strength of the broad iron emission line between the two states. Spectral modeling of the reflection spectra reveals that the inner radius of the optically thick accretion disk evolves from <1.9 r_g to 12 \u00b1 1 r_g (statistical errors at 90% confidence level) from the disk dominant to the power-law dominant state. Assuming in the former case that the inner disk radius is consistent with being at the innermost stable circular orbit, we estimate a black hole spin of a* > 0.94. Given that the bolometric luminosity is similar in the two states, our results indicate that the disk truncation observed in MAXI J1631\u2013479 in the power-law dominant state is unlikely to be driven by a global variation in the accretion rate. We propose that it may instead arise from local instabilities in the inner edge of the accretion disk at high accretion rates. In addition, we find an absorption feature in the spectra centered at 7.33 \u00b1 0.03 keV during the disk dominant state, which is evidence for the rare case that an extremely fast disk wind (v_(out) = 0.067^(+0.001)_(\u22120.004) c) is observed in a low-inclination black hole binary, with the viewing angle of 29\u00b0 \u00b1 1\u00b0 as determined by the reflection modeling.",
"date": "2020-04-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "893",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 30",
"id_number": "CaltechAUTHORS:20200413-123514628",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200413-123514628",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNX17AJ65G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.3847/1538-4357/ab7dc0",
"primary_object": {
"basename": "2003.03465.pdf",
"url": "https://authors.library.caltech.edu/records/sm3vt-p5e61/files/2003.03465.pdf"
},
"related_objects": [
{
"basename": "Xu_2020_ApJ_893_30.pdf",
"url": "https://authors.library.caltech.edu/records/sm3vt-p5e61/files/Xu_2020_ApJ_893_30.pdf"
}
],
"pub_year": "2020",
"author_list": "Xu, Yanjun; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/m4nw6-sj350",
"eprint_id": 102156,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:24:43",
"lastmod": "2026-03-29 20:42:46",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Connors-R-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Sridhar-N",
"name": {
"family": "Sridhar",
"given": "Navin"
},
"orcid": "0000-0002-5519-9550"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John"
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Licklederer-S",
"name": {
"family": "Licklederer",
"given": "Stefan"
},
"orcid": "0000-0002-3720-4408"
}
]
},
"title": "Evidence for Returning Disk Radiation in the Black Hole X-Ray Binary XTE J1550\u2013564",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Astrophysical black holes; black hole physics; Kerr black holes; Atomic physics; Low-mass x-ray binary stars",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 December 31; revised 2020 February 21; accepted 2020 February 26; published 2020 March 27. \n\nWe thank the referee for the diligent comments that helped to improve this paper. J.A.G. acknowledges support from NASA grant NNX15AV31G and from the Alexander von Humboldt Foundation. R.M.T.C. has been supported by NASA grant 80NSSC177K0515. V.G. is supported through the Margarete von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. \n\nThis research has made use of data, software and/or web tools obtained from the High Energy Astrophysics Science Archive Research Center (HEASARC), a service of the Astrophysics Science Division at NASA/GSFC and of the Smithsonian Astrophysical Observatory's High Energy Astrophysics Division. \n\nThis research has made use of ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/). \n\nFacilities: RXTE (PCA; Jahoda et al. 1996), HEASARC. \n\nSoftware: XSPEC v.12.10.1c (Arnaud 1996), XILLVER (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), RELXILL (v1.2.0; Garc\u00eda et al. 2014; Dauser et al. 2014).\n\nPublished - Connors_2020_ApJ_892_47.pdf
Accepted Version - 2002.11873.pdf
",
"abstract": "We explore the accretion properties of the black hole X-ray binary XTE J1550\u2212564 during its outbursts in 1998/99 and 2000. We model the disk, corona, and reflection components of X-ray spectra taken with the Rossi X-ray Timing Explorer, using the relxill suite of reflection models. The key result of our modeling is that the reflection spectrum in the very soft state is best explained by disk self-irradiation, i.e., photons from the inner disk are bent by the strong gravity of the black hole and reflected off the disk surface. This is the first known detection of thermal disk radiation reflecting off the inner disk. There is also an apparent absorption line at ~6.9 keV, which may be evidence of an ionized disk wind. The coronal electron temperature (kT_e) is, as expected, lower in the brighter outburst of 1998/99, explained qualitatively by more efficient coronal cooling due to irradiating disk photons. The disk inner radius is consistent with being within a few times the innermost stable circular orbit throughout the bright-hard-to-soft states (10 s of r_g in gravitational units). The disk inclination is low during the hard state, disagreeing with the binary inclination value, and very close to 90\u00b0 in the soft state, recovering to a lower value when adopting a blackbody spectrum as the irradiating continuum.",
"date": "2020-03-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "892",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 47",
"id_number": "CaltechAUTHORS:20200327-150029432",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200327-150029432",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX15AV31G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "Margarete von Wrangell Fellowship"
},
{
"agency": "European Social Fund"
},
{
"agency": "Ministry of Science, Research and the Arts (Baden-W\u00fcrttemberg)"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab7afc",
"primary_object": {
"basename": "2002.11873.pdf",
"url": "https://authors.library.caltech.edu/records/m4nw6-sj350/files/2002.11873.pdf"
},
"related_objects": [
{
"basename": "Connors_2020_ApJ_892_47.pdf",
"url": "https://authors.library.caltech.edu/records/m4nw6-sj350/files/Connors_2020_ApJ_892_47.pdf"
}
],
"pub_year": "2020",
"author_list": "Connors, Riley M. T.; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kzpaf-knc78",
"eprint_id": 101925,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:20:17",
"lastmod": "2026-03-30 06:18:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Jaodand-Amruta-D",
"name": {
"family": "Jaodand",
"given": "Amruta"
},
"orcid": "0000-0002-3850-6651"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "Matthew J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "Timothy P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Sathyaprakash-Rajath",
"name": {
"family": "Sathyaprakash",
"given": "Rajath"
},
"orcid": "0000-0002-5254-3969"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "The (Re)appearance of NGC 925 ULX-3, a New Transient ULX",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Accretion; Neutron stars; X-ray binary stars; Light curves; Black holes; X-ray transient sources",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 November 20; revised 2020 January 31; accepted 2020 February 17; published 2020 March 16. \n\nWe thank our anonymous referee for useful comments on this paper. This work was supported under NASA contract NNG08FD60C. D.J.W. and M.J.M. acknowledge support from STFC in the form of Ernest Rutherford Fellowships. T.P.R. was funded as part of the STFC consolidated grant ST/K000861/1, and R.S. was funded by STFC studentship grant ST/N50404X/1. The scientific results reported in this article are based on observations made by the Chandra X-ray Observatory, as well as archival observations by XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, archival observations by the NuSTAR mission, a project led by the California Institute of Technology, managed by JPL, and funded by NASA, and observations from the Swift data archive. \n\nFacilities: XMM - Newton X-Ray Multimirror Mission satellite, CXO - , Swift(XRT) - , NuSTAR. - \n\nSoftware: astropy (Astropy Collaboration et al. 2013), CIAO (Fruscione et al. 2006), FTOOLS (Nasa High Energy Astrophysics Science Archive Research Center (Heasarc), 2014), XMM-Newton SAS.\n\nPublished - Earnshaw_2020_ApJ_891_153.pdf
Accepted Version - 2001.00642.pdf
",
"abstract": "We report the discovery of a third ULX in NGC 925 (ULX-3), detected in 2017 November by Chandra at a luminosity of L_X = (7.8 \u00b1 0.8) \u00d7 10\u00b3\u2079 erg s\u207b\u00b9. Examination of archival data for NGC 925 reveals that ULX-3 was detected by Swift at a similarly high luminosity in 2011, as well as by XMM-Newton in 2017 January at a much lower luminosity of L_X = (3.8 \u00b1 0.5) \u00d7 10\u00b3\u2078 erg s\u207b\u00b9. With an additional Chandra nondetection in 2005, this object demonstrates a high dynamic range of flux of factor \u227326. In its high-luminosity detections, ULX-3 exhibits a hard power-law spectrum with \u0393 = 1.6 \u00b1 0.1, whereas the XMM-Newton detection is slightly softer, with \u0393 = 1.8_(-0.1)^(+0.2), and is also well-fitted with a broadened disk model. The long-term light curve is sparsely covered and could be consistent either with the propeller effect or with a large-amplitude superorbital period, both of which are seen in ULXs, in particular those with neutron star accretors. Further systematic monitoring of ULX-3 will allow us to determine the mechanism by which ULX-3 undergoes its extreme variability and to better understand the accretion processes of ULXs.",
"date": "2020-03-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "891",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 153",
"id_number": "CaltechAUTHORS:20200316-150528314",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200316-150528314",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K000861/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/N50404X/1"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab77b8",
"primary_object": {
"basename": "2001.00642.pdf",
"url": "https://authors.library.caltech.edu/records/kzpaf-knc78/files/2001.00642.pdf"
},
"related_objects": [
{
"basename": "Earnshaw_2020_ApJ_891_153.pdf",
"url": "https://authors.library.caltech.edu/records/kzpaf-knc78/files/Earnshaw_2020_ApJ_891_153.pdf"
}
],
"pub_year": "2020",
"author_list": "Earnshaw, Hannah P.; Heida, Marianne; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nnppg-35092",
"eprint_id": 96483,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:17:05",
"lastmod": "2026-03-29 00:39:46",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Maccarone-T-J",
"name": {
"family": "Maccarone",
"given": "Thomas J."
},
"orcid": "0000-0003-0976-4755"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Brumback-M-C",
"name": {
"family": "Brumback",
"given": "McKinley C."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Israel-G-L",
"name": {
"family": "Israel",
"given": "Gian Luca"
}
},
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "Matthew J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Webb-N-A",
"name": {
"family": "Webb",
"given": "Natalie A."
}
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "All at once: transient pulsations, spin down and a glitch from the Pulsating Ultraluminous X-ray Source M82 X-2",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Pulsars; Pulsar timing method; Accretion; X-ray astronomy; Orbital motion; Time series analysis; Fast Fourier transform; Neutron stars; Compact objects",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 May 15; revised 2020 January 11; accepted 2020 January 15; published 2020 March 3. \n\nM.B. thanks the Fulbright Visiting Scholar Program for supporting a 9 month visit at Caltech. M.M. appreciates support from an STFC Ernest Rutherford Fellowship. Part of the pulsar search and optimization software was developed in the framework of the Citizen Computing Pulsar Search (CICLOPS), a project supported by POR FESR Sardegna 20142020 Asse 1 Azione 1.1.3 (code RICERCA_1C-181), call for proposal \"Aiuti per Progetti di Ricerca e Sviluppo 2017,\" managed by Sardegna Ricerche. The authors wish to thank Jim Fuller for insightful conversations on stellar pulsations, Georgios Vasilopoulos for comments on the manuscript, Sergei Popov for pointing out alternative models for magnetar evolution, and Wynn Ho for pointing out an incorrect citation about glitch models in the first version posted on the arXiv. Thanks also to Deepto Chakrabarty, Fred Lamb, Juri Poutanen, Alexander Mushtukov, and Andrew King for multiple insights on accretion theories and competing models for PULXs. \n\nFacilities: NuSTAR (Harrison et al. 2013), Chandra (Weisskopf et al. 2002), ATNF pulsar catalog (Manchester et al. 2005). \n\nSoftware: HEAsoft (HEASARC 2014), FTOOLS (Blackburn et al. 1999; Blackburn 1995), Stingray (Huppenkothen et al. 2016, 2019), HENDRICS (Bachetti 2018), astropy (Astropy Collaboration et al. 2018), PINT (Luo et al. 2019), PRESTO (Ransom 2011).\n\nPublished - Bachetti_2020_ApJ_891_44.pdf
Submitted - 1905.06423.pdf
",
"abstract": "The first pulsating ultraluminous X-ray source (PULX) to be identified is M82 X-2. After the discovery in 2014, NuSTAR observed the M82 field 15 times throughout 2015 and 2016. In this paper, we report the results of pulsation searches in all of these data sets and find only one new detection. This new detection allows us to refine the orbital period of the source and measure an average spin-down rate between 2014 and 2016 of ~\u22126 \u00d7 10\u207b\u00b9\u00b9 Hz s\u207b\u00b9, which is in contrast to the strong spin-up seen during the 2014 observations, representing the first detection of spin-down in a PULX system. Thanks to the improved orbital solution allowed by this new detection, we are also able to detect pulsations in additional segments of the original 2014 data set. We find a glitch superimposed on the very strong and variable spin-up already reported\u2014the first positive glitch identified in a PULX system. We discuss the new findings in the context of current leading models for PULXs.",
"date": "2020-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "891",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 44",
"id_number": "CaltechAUTHORS:20190617-152050717",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190617-152050717",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fulbright Foundation"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Sardegna Ricerche",
"grant_number": "20142020 Asse 1 Azione 1.1.3"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab6d00",
"primary_object": {
"basename": "1905.06423.pdf",
"url": "https://authors.library.caltech.edu/records/nnppg-35092/files/1905.06423.pdf"
},
"related_objects": [
{
"basename": "Bachetti_2020_ApJ_891_44.pdf",
"url": "https://authors.library.caltech.edu/records/nnppg-35092/files/Bachetti_2020_ApJ_891_44.pdf"
}
],
"pub_year": "2020",
"author_list": "Bachetti, Matteo; Maccarone, Thomas J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/50z5b-nh090",
"eprint_id": 101828,
"eprint_status": "archive",
"datestamp": "2023-08-19 20:17:38",
"lastmod": "2026-03-29 15:08:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Deprince-J\u00e9r\u00f4me",
"name": {
"family": "Deprince",
"given": "J."
},
"orcid": "0000-0002-3409-8232"
},
{
"id": "Bautista-M-A",
"name": {
"family": "Bautista",
"given": "M. A."
}
},
{
"id": "Fritzsche-Stephan",
"name": {
"family": "Fritzsche",
"given": "S."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Kallman-Timothy-R",
"name": {
"family": "Kallman",
"given": "T. R."
},
"orcid": "0000-0002-5779-6906"
},
{
"id": "Mendoza-C",
"name": {
"family": "Mendoza",
"given": "C."
}
},
{
"id": "Palmeri-P",
"name": {
"family": "Palmeri",
"given": "P."
}
},
{
"id": "Quinet-P",
"name": {
"family": "Quinet",
"given": "P."
}
}
]
},
"title": "Plasma-environment effects on K lines of astrophysical interest. III. IPs, K thresholds, radiative rates, and Auger widths in Fe\u202fIX \u2013 Fe\u202fXVI",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 plasmas \u2013 atomic data \u2013 X-rays: general",
"note": "\u00a9 2020 ESO. Article published by EDP Sciences. \n\nReceived 8 November 2019; Accepted 29 January 2020; Published online 09 March 2020. \n\nJD is Research Fellow of the Belgian Fund for Research Training in Industry and Agriculture (FRIA) while PP and PQ are, respectively, Research Associate and Research Director of the Belgian Fund for Scientific Research (F.R.S.-FNRS). Financial supports from these organizations, as well as from the NASA Astrophysics Research and Analysis Program (grant 80NSSC17K0345) are gratefully acknowledged. JAG acknowledges support from the Alexander von Humboldt Foundation.\n\nPublished - aa37088-19.pdf
Accepted Version - 2001.11915.pdf
",
"abstract": "Aims. In the context of black-hole accretion disks, we aim to compute the plasma-environment effects on the atomic parameters used to model the decay of K-vacancy states in moderately charged iron ions, namely Fe\u202fIX \u2013 Fe\u202fXVI. \n\nMethods. We used the fully relativistic multiconfiguration Dirac\u2013Fock method approximating the plasma electron\u2013nucleus and electron\u2013electron screenings with a time-averaged Debye\u2013H\u00fcckel potential. \n\nResults. We report modified ionization potentials, K-threshold energies, wavelengths, radiative emission rates, and Auger widths for plasmas characterized by electron temperatures and densities in the ranges 10\u2075\u221210\u2077 K and 10\u00b9\u2078\u221210\u00b2\u00b2 cm\u207b\u00b3. \n\nConclusions. This study confirms that the high-resolution X-ray spectrometers onboard the future XRISM and Athena space missions will be capable of detecting the lowering of the K edges of these ions due to the extreme plasma conditions occurring in accretion disks around compact objects.",
"date": "2020-03",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "635",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A70",
"id_number": "CaltechAUTHORS:20200310-133032776",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200310-133032776",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fonds pour la Formation \u00e0 la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium)"
},
{
"agency": "Fonds de la Recherche Scientifique (FNRS)"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0345"
},
{
"agency": "Alexander von Humboldt Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/201937088",
"primary_object": {
"basename": "aa37088-19.pdf",
"url": "https://authors.library.caltech.edu/records/50z5b-nh090/files/aa37088-19.pdf"
},
"related_objects": [
{
"basename": "2001.11915.pdf",
"url": "https://authors.library.caltech.edu/records/50z5b-nh090/files/2001.11915.pdf"
}
],
"pub_year": "2020",
"author_list": "Deprince, J.; Bautista, M. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8j2j7-avv76",
"eprint_id": 102129,
"eprint_status": "archive",
"datestamp": "2023-08-19 20:19:38",
"lastmod": "2026-03-30 06:18:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Parker-Michael-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Soria-Roberto",
"name": {
"family": "Soria",
"given": "R."
},
"orcid": "0000-0002-4622-796X"
},
{
"id": "Kosec-P",
"name": {
"family": "Kosec",
"given": "P."
}
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Guainazzi-Matteo",
"name": {
"family": "Guainazzi",
"given": "M."
}
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "Fuerst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Sathyaprakash-Rajath",
"name": {
"family": "Sathyaprakash",
"given": "R."
},
"orcid": "0000-0002-5254-3969"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
}
]
},
"title": "XMM-Newton campaign on ultraluminous X-ray source NGC 1313 X-1: wind versus state variability",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, X-rays: binaries, X-rays: individual: NGC 1313 X-1",
"note": "\u00a9 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nReceived: 08 November 2019; Revision received: 19 December 2019; Accepted: 12 January 2020; Published: 15 January 2020. \n\nThis work is based on observations obtained with XMM\u2013Newton, an ESA science mission funded by ESA Member States and USA (NASA). CP, MP, and FF are supported by European Space Agency (ESA) Research Fellowships. We acknowledge support from STFC and ERC Advanced Grant Feedback 340442 and the European Union's Horizon 2020 Programme under the AHEAD AO5 project (grant agreement n. 654215). We also thank J. de Plaa and M. Mehdipour for support in optimizing SPEX and I. Psaradaki for help with PYTHON. We thank the XMM\u2013Newton SOC and, in particular, Jan-Uwe Ness for excellent support in optimizing our observing campaign. We finally acknowledge the anonymous referee for useful comments that improved the clarity of the paper.\n\nPublished - staa118.pdf
Accepted Version - 1911.09568.pdf
",
"abstract": "Most ultraluminous X-ray sources (ULXs) are thought to be powered by neutron stars and black holes accreting beyond the Eddington limit. If the compact object is a black hole or a neutron star with a magnetic field \u227210\u00b9\u00b2\u2009G, the accretion disc is expected to thicken and launch powerful winds driven by radiation pressure. Evidence of such winds has been found in ULXs through the high-resolution spectrometers onboardXMM\u2013Newton, but several unknowns remain, such as the geometry and launching mechanism of these winds. In order to better understand ULX winds and their link to the accretion regime, we have undertaken a major campaign with XMM\u2013Newton to study the ULX NGC 1313 X-1, which is known to exhibit strong emission and absorption features from a mildly relativistic wind. The new observations show clear changes in the wind with a significantly weakened fast component (0.2c) and the rise of a new wind phase which is cooler and slower (0.06\u20130.08c). We also detect for the first time variability in the emission lines which indicates an origin within the accretion disc or in the wind. We describe the variability of the wind in the framework of variable super-Eddington accretion rate and discuss a possible geometry for the accretion disc.",
"date": "2020-03",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "492",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "4646-4665",
"id_number": "CaltechAUTHORS:20200326-143435397",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200326-143435397",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "ESA Member States"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "654215"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/staa118",
"primary_object": {
"basename": "1911.09568.pdf",
"url": "https://authors.library.caltech.edu/records/8j2j7-avv76/files/1911.09568.pdf"
},
"related_objects": [
{
"basename": "staa118.pdf",
"url": "https://authors.library.caltech.edu/records/8j2j7-avv76/files/staa118.pdf"
}
],
"pub_year": "2020",
"author_list": "Pinto, C.; Walton, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/s17b0-mxy83",
"eprint_id": 101591,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:04:56",
"lastmod": "2026-03-30 13:53:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pintore-F",
"name": {
"family": "Pintore",
"given": "F."
}
},
{
"name": {
"family": "Marelli",
"given": "M."
},
"orcid": "0000-0002-8017-0338"
},
{
"name": {
"family": "Salvaterra",
"given": "R."
},
"orcid": "0000-0002-9393-8078"
},
{
"name": {
"family": "Israel",
"given": "G. L."
},
"orcid": "0000-0001-5480-6438"
},
{
"name": {
"family": "Rodr\u00edguez Castillo",
"given": "G. A."
}
},
{
"name": {
"family": "Esposito",
"given": "P."
},
"orcid": "0000-0003-4849-5092"
},
{
"name": {
"family": "Belfiore",
"given": "A."
},
"orcid": "0000-0002-2526-1309"
},
{
"name": {
"family": "De Luca",
"given": "A."
}
},
{
"name": {
"family": "Wolter",
"given": "A."
}
},
{
"name": {
"family": "Mereghetti",
"given": "S."
},
"orcid": "0000-0003-3259-7801"
},
{
"name": {
"family": "Stella",
"given": "L."
},
"orcid": "0000-0002-0018-1687"
},
{
"name": {
"family": "Rigoselli",
"given": "M."
}
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"name": {
"family": "Bernardini",
"given": "F."
},
"orcid": "0000-0001-5326-2010"
},
{
"name": {
"family": "Haberl",
"given": "F."
},
"orcid": "0000-0002-0107-5237"
},
{
"name": {
"family": "Salvaggio",
"given": "C."
}
},
{
"name": {
"family": "Tiengo",
"given": "A."
},
"orcid": "0000-0002-6038-1090"
},
{
"name": {
"family": "Zampieri",
"given": "L."
},
"orcid": "0000-0002-6516-1329"
},
{
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"name": {
"family": "Casella",
"given": "P."
}
},
{
"name": {
"family": "D'Agostino",
"given": "D."
},
"orcid": "0000-0003-2649-0071"
},
{
"name": {
"family": "Dall'Osso",
"given": "S."
}
},
{
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Mapelli",
"given": "M."
},
"orcid": "0000-0001-8799-2548"
},
{
"name": {
"family": "Papitto",
"given": "A."
},
"orcid": "0000-0001-6289-7413"
},
{
"name": {
"family": "Middleton",
"given": "M."
},
"orcid": "0000-0002-8183-2970"
}
]
},
"title": "The Ultraluminous X-Ray Sources Population of the Galaxy NGC 7456",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-ray astronomy; X-ray binary stars; X-ray sources; Neutron stars; Pulsars",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 December 12; revised 2020 January 14; accepted 2020 January 20; published 2020 February 26. \n\nThe scientific results reported in this article are based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. L.S. acknowledges support from the research grant \"iPeska\" (P.I. Andrea Possenti) funded under the INAF national call Prin-SKA/CTA approved with the Presidential Decree 70/2016. G.R. acknowledges the support of high performance computing resources awarded by CINECA (MARCONI and GALILEO), under the ISCRA initiative and the INAF-CIENCA MoU; and also the computing centers of INAF\u2014Osservatorio Astronomico di Trieste and Osservatorio Astrofisico di Catania, under the coordination of the CHIPP project, for the availability of computing resources and support. C.P. is supported by ESA Research Fellowships. D.J.W. and M.M. acknowledges support from STFC in the form of an Ernest Rutherford Fellowship. H.P.E. acknowledges support under NASA contract NNG08FD60C. F.B. is funded by the European Union's Horizon 2020 research and innovation programme under the Marie Sk\u0142odowska Curie grant agreement No. 664931. This research was supported by high performance computing resources at New York University Abu Dhabi. H.P.E. acknowledges support under NASA contract NNG08FD60C. T.P.R. acknowledges support from STFC as part of the consolidated grant ST/K000861/1. A.P. acknowledges financial support from the Italian Space Agency and National Institute for Astrophysics, ASI/INAF, under agreements ASI\u2013INAF I/037/12/0 and ASI\u2013INAF n.2017-14-H.0. \n\nWe acknowledge funding in the framework of the project ULTraS ASI\u2013INAF contract No. 2017-14-H.0, and project ASI\u2013INAF contract I/037/12/0.\n\nPublished - Pintore_2020_ApJ_890_166.pdf
Accepted Version - 2001.08752.pdf
",
"abstract": "Ultraluminous X-ray sources (ULXs) are a class of accreting compact objects with X-ray luminosities above 10\u00b3\u2079 erg s\u207b\u00b9. The ULX population counts several hundred objects but only a fraction are well studied. Here we present a detailed analysis of all ULXs hosted in the galaxy NGC 7456. It was observed in X-rays only once in the past (in 2005) by XMM-Newton. but the observation was short and strongly affected by high background. In 2018, we obtained a new, deeper (~90 ks) XMM-Newton observation that allowed us to perform a detailed characterization of the ULXs hosted in the galaxy. ULX-1 and ULX-2, the two brightest objects (L_X ~ 6\u221210 \u00d7 10\u00b3\u2079 erg s\u207b\u00b9), have spectra that can be described by a model with two thermal components, as often found in ULXs. ULX-1 also shows one order of magnitude in flux variability on short-term timescales (hundreds to thousands of kiloseconds). The other sources (ULX-3 and ULX-4) show flux changes of at least an order of magnitude, and these objects may be candidate transient ULXs, although longer X-ray monitoring or further studies are required to ascribe them to the ULX population. In addition, we found a previously undetected source that might be a new candidate ULX (labeled as ULX-5), with a luminosity of ~10\u00b3\u2079 erg s\u207b\u00b9 and hard power-law spectral shape, whose nature is still unclear and for which a background active galactic nucleus cannot be excluded. We discuss the properties of all the ULXs in NGC 7456 within the framework of super-Eddington accretion onto stellar-mass compact objects. Although no pulsations were detected, we cannot exclude that the sources host neutron stars.",
"date": "2020-02-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "890",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 166",
"id_number": "CaltechAUTHORS:20200226-134844778",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200226-134844778",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "ESA Member States"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "CINECA"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K000861/1"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "664931"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab6ffd",
"primary_object": {
"basename": "2001.08752.pdf",
"url": "https://authors.library.caltech.edu/records/s17b0-mxy83/files/2001.08752.pdf"
},
"related_objects": [
{
"basename": "Pintore_2020_ApJ_890_166.pdf",
"url": "https://authors.library.caltech.edu/records/s17b0-mxy83/files/Pintore_2020_ApJ_890_166.pdf"
}
],
"pub_year": "2020",
"author_list": "Pintore, F.; Marelli, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/a9c0e-j1d30",
"eprint_id": 101247,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:00:59",
"lastmod": "2026-03-30 15:25:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Sridhar-Navin",
"name": {
"family": "Sridhar",
"given": "Navin"
},
"orcid": "0000-0002-5519-9550"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Steiner-James-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Connors-Riley-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Grinberg-Victoria",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Evolution of the Accretion Disk\u2013Corona during the Bright Hard-to-soft State Transition: A Reflection Spectroscopic Study with GX 339\u20134",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "High energy astrophysics; Compact objects; Black hole physics; Low-mass x-ray binary stars; Accretion; X-ray astronomy; Spectroscopy; Astronomy data modeling; X-ray sources; General relativity; Gravitation; Astrophysical black holes",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 September 9; revised 2019 December 18; accepted 2019 December 22; published 2020 February 12. \n\nN.S. acknowledges the support from DST-INSPIRE, Caltech SURF, and Columbia University Dean's fellowships. J.A.G. acknowledges the support from NASA grant 80NSSC19K1020 and from the Alexander von Humboldt Foundation. R.M.T.C. has been supported by NASA ADAP grant 80NSSC17K0515. V.G. is supported through the Margarete von Wrangell fellowship of the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. We also thank Ronald A. Remillard for his contribution toward processing the data, which have been used in our analysis. This work was partially supported under NASA contract No. NNG08FD60C. \n\nFacility: RXTE (PCA). \n\nSoftware: xspec v12.9.1q (Arnaud 1996), relxill v1.4 (Dauser et al. 2014; Garc\u00eda et al. 2014a), xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), pcacorr (Garc\u00eda et al. 2014b).\n\nPublished - Sridhar_2020_ApJ_890_53.pdf
Accepted Version - 1912.11447.pdf
Erratum - Sridhar_2020_ApJ_904_201.pdf
",
"abstract": "We present the analysis of several observations of the black hole binary GX 339\u20134 during its bright intermediate states from two different outbursts (2002 and 2004), as observed by the RXTE/Proportional Counter Array. We perform a consistent study of its reflection spectrum by employing the RELXILL family of relativistic reflection models to probe the evolutionary properties of the accretion disk including the inner disk radius (R_(in)), ionization parameter (\u03be), temperatures of the inner disk (T_(in)), corona (kT_e), and its optical depth (\u03c4). Our analysis indicates that the disk inner edge approaches the innermost stable circular orbit during the early onset of the bright hard state, and that the truncation radius of the disk remains low (<9 R_g) throughout the transition from hard to soft state. This suggests that the changes observed in the accretion disk properties during the state transition are driven by variation in accretion rate, and not necessarily due to changes in the inner disk's radius. We compare the aforementioned disk properties in two different outbursts with state transitions occurring at dissimilar luminosities and find identical evolutionary trends in the disk properties, with differences only seen in the corona's kT_e and \u03c4. We also perform an analysis by employing a self-consistent Comptonized accretion disk model accounting for the scatter of disk photons by the corona, and measure the low inner disk truncation radius across the bright intermediate states, using the temperature-dependent values of the spectral hardening factor, thereby independently confirming our results from the reflection analysis.",
"date": "2020-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "890",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 53",
"id_number": "CaltechAUTHORS:20200212-134110015",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200212-134110015",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Department of Science and Technology (India)"
},
{
"agency": "Caltech Summer Undergraduate Research Fellowship (SURF)"
},
{
"agency": "Columbia University"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1020"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "Baden-W\u00fcrttemberg Stiftung"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
}
]
},
"local_group": {
"items": [
{
"id": "Astronomy-Department"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab64f5",
"primary_object": {
"basename": "1912.11447.pdf",
"url": "https://authors.library.caltech.edu/records/a9c0e-j1d30/files/1912.11447.pdf"
},
"related_objects": [
{
"basename": "Sridhar_2020_ApJ_890_53.pdf",
"url": "https://authors.library.caltech.edu/records/a9c0e-j1d30/files/Sridhar_2020_ApJ_890_53.pdf"
},
{
"basename": "Sridhar_2020_ApJ_904_201.pdf",
"url": "https://authors.library.caltech.edu/records/a9c0e-j1d30/files/Sridhar_2020_ApJ_904_201.pdf"
}
],
"pub_year": "2020",
"author_list": "Sridhar, Navin; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/n30ph-h2c71",
"eprint_id": 101248,
"eprint_status": "archive",
"datestamp": "2023-08-22 04:01:07",
"lastmod": "2026-03-29 15:18:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hare-J",
"name": {
"family": "Hare",
"given": "Jeremy"
},
"orcid": "0000-0002-8548-482X"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Buisson-D-J-K",
"name": {
"family": "Buisson",
"given": "Douglas J. K."
}
},
{
"id": "Clavel-M",
"name": {
"family": "Clavel",
"given": "Ma\u00efca"
},
"orcid": "0000-0003-0724-2742"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "Poshak"
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
}
]
},
"title": "NuSTAR Observations of the Transient Galactic Black Hole Binary Candidate Swift J1858.6\u20130814: A New Sibling of V404 Cyg and V4641 Sgr?",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Stellar mass black holes; X-ray transient sources; Lowmass X-ray binary stars",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 November 4; revised 2019 December 27; accepted 2020 January 8; published 2020 February 12. \n\nThis work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). J.H. and J.A.T. acknowledge partial support from NuSTAR Guest Observer grant 80NSSC19K0404. J.H. acknowledges support from an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by the USRA through a contract with NASA. D.J.W. acknowledges support from STFC in the form of an Ernest Rutherford Fellowship. M.C. acknowledges support from the Centre National d'Etudes Spatiales (CNES). J.A.G. acknowledges support from NASA grant 80NSSC19K1020 and from the Alexander von Humboldt Foundation. We thank the anonymous referee for providing useful comments which have improved the quality of this paper. \n\nSoftware: XSPEC (v12.10.1; Arnaud 1996), NUSTARDAS (v1.8.0), NICERDAS (V005), Stingray (Huppenkothen et al. 2017), Xselect (v2.4e), Matplotlib (Hunter 2007), HEASOFT (v6.25), MWDust (Bovy et al. 2016), XILLVER (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), RELXILL (v1.2.0; Dauser et al. 2014; Garc\u00eda et al. 2014).\n\nPublished - Hare_2020_ApJ_890_57.pdf
Accepted Version - 2001.03214.pdf
",
"abstract": "Swift J1858.6\u22120814 was discovered by the Burst Alert Telescope on Swift on 2018 October 25. Here we report on the first follow-up Nuclear Spectroscopic Telescope Array (NuSTAR) observation of the source, which shows variability spanning two orders of magnitude in count rate on timescales of ~10\u2013100 s. The power spectrum of the source does not show any quasi-periodic oscillations or periodicity, but has a large fractional rms amplitude of 147% \u00b1 3%, exhibiting a number of large flares throughout the observation. The hardness ratio (defined as R_(10\u201379keV)/R_(3\u201310keV)) of the flares tends to be soft, while the source spans a range of hardness ratios during nonflaring periods. The X-ray spectrum of the source shows strong reflection features, which become more narrow and peaked during the nonflaring intervals. We fit an absorbed relativistic reflection model to the source spectra to place physical constraints on the system. Most notably, we find that the source exhibits a large and varying intrinsic absorbing column density (N_H = (1.4\u20134.2) \u00d7 10\u00b2\u00b3 cm\u207b\u00b2). This large intrinsic absorption is further supported by the energy spectra extracted from two flares observed simultaneously by NuSTAR and the Neutron Star Interior Composition Explorer. We find that the inner accretion disk of the source has a low inclination, I < 29\u2218 (3\u03c3 upper limit), while the iron abundance in the disk is close to solar, A_(Fe) = 1.0 \u00b1 0.3. We set a 90% confidence upper limit on the inner radius of the accretion disk of r_(in) < 8r_(ISCO) and, by fixing r_(in) to be at r_(ISCO), a 90% confidence lower limit on the spin of the black hole of a\u2217 > 0.0. Finally, we compare the properties of Swift J1858.6\u22120814 to those of V404 Cygni and V4641 Sgr, which both show rapid flaring and a strong and variable absorption.",
"date": "2020-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "890",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 57",
"id_number": "CaltechAUTHORS:20200212-140525387",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200212-140525387",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0404"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1020"
},
{
"agency": "Alexander von Humboldt Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab6a12",
"primary_object": {
"basename": "2001.03214.pdf",
"url": "https://authors.library.caltech.edu/records/n30ph-h2c71/files/2001.03214.pdf"
},
"related_objects": [
{
"basename": "Hare_2020_ApJ_890_57.pdf",
"url": "https://authors.library.caltech.edu/records/n30ph-h2c71/files/Hare_2020_ApJ_890_57.pdf"
}
],
"pub_year": "2020",
"author_list": "Hare, Jeremy; Tomsick, John A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dzhkn-p3e84",
"eprint_id": 101649,
"eprint_status": "archive",
"datestamp": "2023-08-19 19:48:46",
"lastmod": "2026-03-29 21:37:12",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rojas-A-F",
"name": {
"family": "Rojas",
"given": "A. F."
},
"orcid": "0000-0003-0006-8681"
},
{
"id": "Sani-E",
"name": {
"family": "Sani",
"given": "E."
}
},
{
"id": "Gavignaud-I",
"name": {
"family": "Gavignaud",
"given": "I."
}
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Lamperti-I",
"name": {
"family": "Lamperti",
"given": "I."
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Trakhtenbrot-B",
"name": {
"family": "Trakhtenbrot",
"given": "B."
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Schawinski-K",
"name": {
"family": "Schawinski",
"given": "K."
},
"orcid": "0000-0001-5464-0888"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "K."
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Bauer-F-E",
"name": {
"family": "Bauer",
"given": "F. E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Bischetti-M",
"name": {
"family": "Bischetti",
"given": "M."
}
},
{
"id": "Boissay-Malaquin-R",
"name": {
"family": "Boissay-Malaquin",
"given": "R."
}
},
{
"id": "Bongiorno-A",
"name": {
"family": "Bongiorno",
"given": "A."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kakkad-D",
"name": {
"family": "Kakkad",
"given": "D."
}
},
{
"id": "Masetti-N",
"name": {
"family": "Masetti",
"given": "N."
},
"orcid": "0000-0001-9487-7740"
},
{
"id": "Ricci-F",
"name": {
"family": "Ricci",
"given": "F."
},
"orcid": "0000-0001-5742-5980"
},
{
"id": "Shimizu-Taro",
"name": {
"family": "Shimizu",
"given": "T."
},
"orcid": "0000-0002-2125-4670"
},
{
"id": "Stalevski-M",
"name": {
"family": "Stalevski",
"given": "M."
},
"orcid": "0000-0001-5146-8330"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Vietri-G",
"name": {
"family": "Vietri",
"given": "G."
}
}
]
},
"title": "BAT AGN Spectroscopic Survey \u2013 XIX. Type\u20091 versus type\u20092 AGN dichotomy from the point of view of ionized outflows",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: nuclei \u2013 quasars: emission lines",
"note": "\u00a9 2019 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 November 27. Received 2019 October 30; in original form 2019 August 5. Published: 18 December 2019. \n\nThe authors thank the anonymous referee for the constructive comments and suggestions. We are grateful to Prof. M. Elitzur for fruitful discussion on outflow statistics. We acknowledge support from the Ministry of Education, Science, and Technological Development of the Republic of Serbia through the projects Astrophysical Spectroscopy of Extragalactic Objects #176001 (MS) and Gravitation and the Large Scale Structure of the Universe #176003 (MS); CONICYT grants Basal-CATA Basal AFB-170002 (FEB, FR), FONDECYT Postdoctorado 3180506 (FR); the Ministry of Economy, Development and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS (FEB); NASA through ADAP award NNH16CT03C (MK). KO acknowledges support from the Japan Society for the Promotion of Science (JSPS, ID: 17321). MB acknowledges financial support from ASI and INAF under the contract 2017-14-H.0 ASI-INAF. This research project was supported by the DFG Cluster of Excellence 'Origin and Structure of the Universe' (www.universe-cluster.de).\n\nPublished - stz3386.pdf
Accepted Version - 1911.12395.pdf
",
"abstract": "We present a detailed study of ionized outflows in a large sample of \u223c650 hard X-ray-detected active galactic neuclei (AGNs). Using optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS), we are able to reveal the faint wings of the [O\u2009III] emission lines associated with outflows covering, for the first time, an unexplored range of low AGN bolometric luminosity at low redshift (z \u223c0.05). We test if and how the incidence and velocity of ionized outflow is related to AGN physical parameters: black hole mass (\u2060M_(BH)\u2060), gas column density (\u2060N_H\u2060), Eddington ratio (\u2060\u03bb_(Edd)\u2060), [O\u2009III], X-ray, and bolometric luminosities. We find a higher occurrence of ionized outflows in type\u20091.9 (55 per\u2009cent) and type\u20091 AGNs (46 per\u2009cent) with respect to type\u20092 AGNs (24 per\u2009cent). While outflows in type\u20092 AGNs are evenly balanced between blue and red velocity offsets with respect to the [O\u2009III] narrow component, they are almost exclusively blueshifted in type\u20091 and type\u20091.9 AGNs. We observe a significant dependence between the outflow occurrence and accretion rate, which becomes relevant at high Eddington ratios [log(\u2060\u03bb_(Edd)\u2060) \u2273 \u22121.7]. We interpret such behaviour in the framework of covering factor-Eddington ratio dependence. We do not find strong trends of the outflow maximum velocity with AGN physical parameters, as an increase with bolometric luminosity can be only identified when including samples of AGNs at high luminosity and high redshift taken from literature.",
"date": "2020-02",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "491",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "5867-5880",
"id_number": "CaltechAUTHORS:20200302-105705001",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200302-105705001",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Ministry of Education and Science (Serbia)",
"grant_number": "176001"
},
{
"agency": "Ministry of Education and Science (Serbia)",
"grant_number": "176003"
},
{
"agency": "BASAL-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3180506"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "17321"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stz3386",
"primary_object": {
"basename": "1911.12395.pdf",
"url": "https://authors.library.caltech.edu/records/dzhkn-p3e84/files/1911.12395.pdf"
},
"related_objects": [
{
"basename": "stz3386.pdf",
"url": "https://authors.library.caltech.edu/records/dzhkn-p3e84/files/stz3386.pdf"
}
],
"pub_year": "2020",
"author_list": "Rojas, A. F.; Sani, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/d5f5n-73s57",
"eprint_id": 101638,
"eprint_status": "archive",
"datestamp": "2023-08-19 19:48:31",
"lastmod": "2026-03-30 14:01:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Canizares-C-R",
"name": {
"family": "Canizares",
"given": "C. R."
}
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Kosec-P",
"name": {
"family": "Kosec",
"given": "P."
}
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Soria-Roberto",
"name": {
"family": "Soria",
"given": "R."
},
"orcid": "0000-0002-4622-796X"
},
{
"id": "Tao-Lian",
"name": {
"family": "Tao",
"given": "L."
}
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "N. A."
}
}
]
},
"title": "Discovery of a soft X-ray lag in the ultraluminous X-ray source NGC\u00a01313\u00a0X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013X-rays: binaries \u2013 X-rays: individual: NGC 1313 X-1",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 November 24. Received 2019 November 21; in original form 2019 November 4. Published: 03 December 2019. \n\nAuthors thank the referee, Thomas Dauser, for helpful comments that improved this paper. EK acknowledges support from NASA Award Number 80NSSC19K0176. CP is supported by ESA Research Fellowships. TPR thanks STFC for support as part of the consolidated grant ST/K000861/1. CRC acknowledges support by the Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 to MIT, which is in turn supported by NASA under contract NAS8-03060.\n\nPublished - stz3318.pdf
Submitted - 1911.09582.pdf
",
"abstract": "Ultraluminous X-ray sources (ULXs) provide a unique opportunity to probe the geometry and energetics of super-Eddington accretion. The radiative processes involved in super-Eddington accretion are not well understood, and so studying correlated variability between different energy bands can provide insights into the causal connection between different emitting regions. We present a spectral-timing analysis of NGC 1313 X-1 from a recent XMM\u2013Newton campaign. The spectra can be decomposed into two thermal-like components, the hotter of which may originate from the inner accretion disc, and the cooler from an optically thick outflow. We find correlated variability between hard (2\u201310 keV) and soft (0.3\u20132 keV) bands on kilosecond time-scales, and find a soft lag of \u223c150 s. The covariance spectrum suggests that emission contributing to the lags is largely associated with the hotter of the two thermal-like components, likely originating from the inner accretion flow. This is only the third ULX to exhibit soft lags. The lags range over three orders of magnitude in amplitude, but all three are \u223c5\u201320 per cent of the corresponding characteristic variability time-scales. If these soft lags can be understood in the context of a unified picture of ULXs, then lag time-scales may provide constraints on the density and extent of radiatively driven outflows.",
"date": "2020-02",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "491",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "5172-5178",
"id_number": "CaltechAUTHORS:20200228-123042359",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200228-123042359",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC19K0176"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K000861/1"
},
{
"agency": "Smithsonian Astrophysical Observatory",
"grant_number": "SV3-73016"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stz3318",
"primary_object": {
"basename": "stz3318.pdf",
"url": "https://authors.library.caltech.edu/records/d5f5n-73s57/files/stz3318.pdf"
},
"related_objects": [
{
"basename": "1911.09582.pdf",
"url": "https://authors.library.caltech.edu/records/d5f5n-73s57/files/1911.09582.pdf"
}
],
"pub_year": "2020",
"author_list": "Kara, E.; Pinto, C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/87qdd-8eb27",
"eprint_id": 101069,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:54",
"lastmod": "2026-03-29 19:21:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R. L., Jr."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
}
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Ho",
"given": "G. C."
}
},
{
"name": {
"family": "Jian",
"given": "L. K."
},
"orcid": "0000-0002-6849-5527"
},
{
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Odstrcil",
"given": "D."
}
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Badman",
"given": "S. T."
},
"orcid": "0000-0002-6145-436X"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Korreck",
"given": "K. E."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Larson",
"given": "D. E."
}
},
{
"name": {
"family": "Livi",
"given": "Roberto"
}
},
{
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"name": {
"family": "Whittlesey",
"given": "Phyllis"
}
}
]
},
"title": "Energetic Particle Increases Associated with Stream Interaction Regions",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar activity; Fast solar wind",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 13; revised 2019 October 4; accepted 2019 October 7; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nThis work was supported by NASA's Parker Solar Probe Mission, contract NNN06AA01C. We thank all the scientists and engineers who have worked hard to make PSP a successful mission. In particular, we thank B. Kecman and W.R. Cook, without whom the EPI-Hi instrument would not be possible. S.D.B. acknowledges support of the Leverhulme Trust Visiting Professorship program. We gratefully acknowledge the test and calibration support provided by Michigan State University's National Superconducting Cyclotron Laboratory, Texas A&M University's Cyclotron Institute, and the Lawrence Berkeley National Laboratory's 88-inch Cyclotron Laboratory.\n\nPublished - pdf
Accepted Version - 1912.08244.pdf
",
"abstract": "The Parker Solar Probe was launched on 2018 August 12 and completed its second orbit on 2019 June 19 with perihelion of 35.7 solar radii. During this time, the Energetic Particle Instrument-Hi (EPI-Hi, one of the two energetic particle instruments comprising the Integrated Science Investigation of the Sun, IS\u2299IS) measured seven proton intensity increases associated with stream interaction regions (SIRs), two of which appear to be occurring in the same region corotating with the Sun. The events are relatively weak, with observed proton spectra extending to only a few MeV and lasting for a few days. The proton spectra are best characterized by power laws with indices ranging from \u22124.3 to \u22126.5, generally softer than events associated with SIRs observed at 1 au and beyond. Helium spectra were also obtained with similar indices, allowing He/H abundance ratios to be calculated for each event. We find values of 0.016\u20130.031, which are consistent with ratios obtained previously for corotating interaction region events with fast solar wind \u2264 600 km s\u207b\u00b9. Using the observed solar wind data combined with solar wind simulations, we study the solar wind structures associated with these events and identify additional spacecraft near 1 au appropriately positioned to observe the same structures after some corotation. Examination of the energetic particle observations from these spacecraft yields two events that may correspond to the energetic particle increases seen by EPI-Hi earlier.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 20",
"id_number": "CaltechAUTHORS:20200203-104219201",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-104219201",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Leverhulme Trust"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ab4c38",
"primary_object": {
"basename": "1912.08244.pdf",
"url": "https://authors.library.caltech.edu/records/87qdd-8eb27/files/1912.08244.pdf"
},
"related_objects": [
{
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/87qdd-8eb27/files/pdf"
}
],
"pub_year": "2020",
"author_list": "Cohen, C. M. S.; Christian, E. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/1bfnf-pry08",
"eprint_id": 101063,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:20",
"lastmod": "2026-03-28 20:48:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Joyce-C-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "McComas-D-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Schwadron-N-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "McNutt-R-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Mitchell-D-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Hill-M-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Roelof-E-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Szalay-J-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Rankin-J-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Desai-M-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Giacalone-J",
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"id": "Matthaeus-W-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
}
]
},
"title": "Energetic Particle Observations from the Parker Solar Probe Using Combined Energy Spectra from the IS\u2299IS Instrument Suite",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Interplanetary physics; Corotating streams; Interplanetary particle acceleration; Interplanetary shocks",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 20; revised 2019 November 6; accepted 2019 November 18; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nThis work was supported as a part of the Integrated Science Investigations of the Sun on NASA's Parker Solar Probe mission, under contract NNN06AA01C. The IS\u2299IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). Simulation results have been provided by the Community Coordinated Modeling Center at Goddard Space Flight Center through their public Runs on Request system (http://ccmc.gsfc.nasa.gov). The ENLIL Model was developed by D. Odstrcil at the University of Colorado at Boulder.\n\nPublished - pdf
Accepted Version - 1912.02339.pdf
",
"abstract": "The Integrated Science Investigations of the Sun (IS\u2299IS) instrument suite includes two Energetic Particle instruments: EPI-Hi, designed to measure ions from ~1 to 200 MeV nuc\u207b\u00b9, and EPI-Lo, designed to measure ions from ~20 to ~15 MeV nuc\u207b\u00b9. We present an analysis of eight energetic proton events observed across the energy range of both instruments during Parker Solar Probe's (PSP) first two orbits in order to examine their combined energy spectra. Background corrections are applied to help resolve spectral breaks between the two instruments and are shown to be effective. In doing so we demonstrate that even in the early stages of calibration, IS\u2299IS is capable of producing reliable spectral observations across broad energy ranges. In addition to making groundbreaking measurements very near the Sun, IS\u2299IS also characterizes energetic particle populations over a range of heliocentric distances inside 1 au. During the first two orbits, IS\u2299IS observed energetic particle events from a single corotating interaction region (CIR) at three different distances from the Sun. The events are separated by two Carrington rotations and just 0.11 au in distance; however, the relationship shown between proton intensities and proximity of the spacecraft to the source region shows evidence of the importance of transport effects on observations of energetic particles from CIRs. Future IS\u2299IS observations of similar events over larger distances will help disentangle the effects of CIR-related acceleration and transport. We apply similar spectral analyses to the remaining five events, including four that are likely related to stream interaction regions (SIRs) and one solar energetic particle (SEP) event.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 41",
"id_number": "CaltechAUTHORS:20200203-092721619",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092721619",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4365/ab5948",
"primary_object": {
"basename": "1912.02339.pdf",
"url": "https://authors.library.caltech.edu/records/1bfnf-pry08/files/1912.02339.pdf"
},
"related_objects": [
{
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/1bfnf-pry08/files/pdf"
}
],
"pub_year": "2020",
"author_list": "Joyce, C. J.; McComas, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z10mw-zq376",
"eprint_id": 101158,
"eprint_status": "archive",
"datestamp": "2023-08-19 19:45:29",
"lastmod": "2026-03-30 08:50:20",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jurewicz-Amy-J-G",
"name": {
"family": "Jurewicz",
"given": "A. J. G."
},
"orcid": "0000-0002-3282-5782"
},
{
"id": "Rieck-K-D",
"name": {
"family": "Rieck",
"given": "K. D."
}
},
{
"id": "Hervig-Richard",
"name": {
"family": "Hervig",
"given": "R."
},
"orcid": "0000-0001-7892-5423"
},
{
"id": "Burnett-D-S",
"name": {
"family": "Burnett",
"given": "D. S."
},
"orcid": "0000-0001-9521-8675"
},
{
"id": "Wadhwa-Meenakshi",
"name": {
"family": "Wadhwa",
"given": "M."
},
"orcid": "0000-0001-9187-1255"
},
{
"id": "Olinger-Chad-T",
"name": {
"family": "Olinger",
"given": "C. T."
},
"orcid": "0000-0002-9509-6345"
},
{
"id": "Wiens-Roger-C",
"name": {
"family": "Wiens",
"given": "R. C."
},
"orcid": "0000-0002-3409-7344"
},
{
"id": "Laming-J-Martin",
"name": {
"family": "Laming",
"given": "J. M."
},
"orcid": "0000-0002-3362-7040"
},
{
"id": "Guan-Yunbin",
"name": {
"family": "Guan",
"given": "Y."
},
"orcid": "0000-0002-7636-3735"
},
{
"id": "Huss-Gary-R",
"name": {
"family": "Huss",
"given": "G. R."
},
"orcid": "0000-0003-4281-7839"
},
{
"id": "Reisenfeld-Daniel-B",
"name": {
"family": "Reisenfeld",
"given": "D. B."
},
"orcid": "0000-0003-1874-9450"
},
{
"id": "Williams-P",
"name": {
"family": "Williams",
"given": "P."
}
}
]
},
"title": "Magnesium isotopes of the bulk solar wind from Genesis diamond\u2010like carbon films",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2020 The Authors. Meteoritics & Planetary Science published by Wiley Periodicals, Inc. on behalf of The Meteoritical Society (MET). This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nReceived 09 December 2018; revision accepted 10 December 2019. Version of Record online: 22 January 2020. \n\nSIMS analysis at Arizona State University National SIMS facility, was supported by EAR0622775. This work was initiated using Genesis Mission Funds, including JPL subcontract #1354958. Subsequent work was supported by NASA LARS Grants # NNX14AF26G and 80NSSC17K0025 (DSB, AJ); NNX17AE73G (GRH); NNH15AZ25I and NNH15AZ67I (RW); 80NSSC18K0740 (DBR), NNH16AC39I, NNH17AE96I, and NNH17AE60I (JML); as well as by basic research funds of the Chief of Naval Research (JML) and NASA Emerging Worlds award NNX15AH41G (MW). Thanks to J. Ziegler, USNA Annapolis for advice on SRIM, L. Williams for oversight using the ASU Cameca IMS 6f, Phil Janney for supporting M. Wadhwa in the Isotope Cosmochemistry and Geochronology Laboratory, and Stephen Romaniello for his discussions on Mg isotopes. Tom Friedmann provided significant insight into the material properties of the DLC made at Sandia National Laboratory. Bernard Marty and three anonymous reviewers made excellent suggestions that greatly improved the quality of this manuscript. Special thanks to associate editor Marc Caffee for his effort and patience.\n\nPublished - Jurewicz_et_al-2020-Meteoritics___Planetary_Science.pdf
Supplemental Material - maps13439-sup-0001-supinfo.zip
Supplemental Material - maps13439-sup-0002-text.pdf
",
"abstract": "NASA's Genesis Mission returned solar wind (SW) to the Earth for analysis to derive the composition of the solar photosphere from solar material. SW analyses control the precision of the derived solar compositions, but their ultimate accuracy is limited by the theoretical or empirical models of fractionation due to SW formation. Mg isotopes are \"ground truth\" for these models since, except for CAIs, planetary materials have a uniform Mg isotopic composition (within \u22641\u2030) so any significant isotopic fractionation of SW Mg is primarily that of SW formation and subsequent acceleration through the corona. This study analyzed Mg isotopes in a bulk SW diamond\u2010like carbon (DLC) film on silicon collector returned by the Genesis Mission. A novel data reduction technique was required to account for variable ion yield and instrumental mass fractionation (IMF) in the DLC. The resulting SW Mg fractionation relative to the DSM\u20103 laboratory standard was (\u221214.4\u2030, \u221230.2\u2030) \u00b1 (4.1\u2030, 5.5\u2030), where the uncertainty is 2\u01a1 SE of the data combined with a 2.5\u2030 (total) error in the IMF determination. Two of the SW fractionation models considered generally agreed with our data. Their possible ramifications are discussed for O isotopes based on the CAI nebular composition of McKeegan et al. (2011).",
"date": "2020-02",
"date_type": "published",
"publication": "Meteoritics and Planetary Science",
"volume": "55",
"number": "2",
"publisher": "Meteoritical Society",
"pagerange": "352-375",
"id_number": "CaltechAUTHORS:20200206-112311510",
"issn": "1086-9379",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200206-112311510",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "EAR-0622775"
},
{
"agency": "JPL",
"grant_number": "1354958"
},
{
"agency": "NASA",
"grant_number": "NNX14AF26G"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0025"
},
{
"agency": "NASA",
"grant_number": "NNX17AE73G"
},
{
"agency": "NASA",
"grant_number": "NNH15AZ25I"
},
{
"agency": "NASA",
"grant_number": "NNH15AZ67I"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0740"
},
{
"agency": "NASA",
"grant_number": "NNH16AC39I"
},
{
"agency": "NASA",
"grant_number": "NNH17AE96I"
},
{
"agency": "NASA",
"grant_number": "NNH17AE60I"
},
{
"agency": "Chief of Naval Research"
},
{
"agency": "NASA",
"grant_number": "NNX15AH41G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Division-of-Geological-and-Planetary-Sciences"
}
]
},
"doi": "10.1111/maps.13439",
"pmcid": "PMC7079557",
"primary_object": {
"basename": "Jurewicz_et_al-2020-Meteoritics___Planetary_Science.pdf",
"url": "https://authors.library.caltech.edu/records/z10mw-zq376/files/Jurewicz_et_al-2020-Meteoritics___Planetary_Science.pdf"
},
"related_objects": [
{
"basename": "maps13439-sup-0001-supinfo.zip",
"url": "https://authors.library.caltech.edu/records/z10mw-zq376/files/maps13439-sup-0001-supinfo.zip"
},
{
"basename": "maps13439-sup-0002-text.pdf",
"url": "https://authors.library.caltech.edu/records/z10mw-zq376/files/maps13439-sup-0002-text.pdf"
}
],
"pub_year": "2020",
"author_list": "Jurewicz, A. J. G.; Rieck, K. D.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/69xme-na075",
"eprint_id": 101066,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:41",
"lastmod": "2026-03-30 05:34:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bandyopadhyay-Riddhi",
"name": {
"family": "Bandyopadhyay",
"given": "Riddhi"
},
"orcid": "0000-0002-6962-0959"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "Parashar",
"given": "t. N."
},
"orcid": "0000-0003-0602-8381"
},
{
"name": {
"family": "Chhiber",
"given": "R."
},
"orcid": "0000-0002-7174-6948"
},
{
"name": {
"family": "Ruffolo",
"given": "D."
},
"orcid": "0000-0003-3414-9666"
},
{
"name": {
"family": "Goldstein",
"given": "M. L."
},
"orcid": "0000-0002-5317-988X"
},
{
"name": {
"family": "Maruca",
"given": "B. A."
},
"orcid": "0000-0002-2229-5618"
},
{
"name": {
"family": "Chasapis",
"given": "A."
},
"orcid": "0000-0001-8478-5797"
},
{
"name": {
"family": "Qudsi",
"given": "R."
},
"orcid": "0000-0001-8358-0482"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Bale",
"given": "Stuart D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Bonnell",
"given": "J. W."
}
},
{
"name": {
"family": "Dudok de Wit",
"given": "T."
},
"orcid": "0000-0002-4401-0943"
},
{
"name": {
"family": "Goetz",
"given": "Keith"
},
"orcid": "0000-0003-0420-3633"
},
{
"name": {
"family": "Harvey",
"given": "Peter R."
}
},
{
"name": {
"family": "MacDowall",
"given": "Robert J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Malaspina",
"given": "David M."
},
"orcid": "0000-0003-1191-1558"
},
{
"name": {
"family": "Pulupa",
"given": "Mark"
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Velli",
"given": "M."
},
"orcid": "0000-0002-2381-3106"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Korreck",
"given": "K. E."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Stevens",
"given": "M."
},
"orcid": "0000-0002-7728-0085"
},
{
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Raouafi",
"given": "N."
},
"orcid": "0000-0003-2409-3742"
}
]
},
"title": "Observations of Energetic-particle Population Enhancements along Intermittent Structures near the Sun from the Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Interplanetary turbulence; Interplanetary physics; Interplanetary magnetic fields; Solar wind; Slow solar wind",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 14; revised 2019 November 29; accepted 2019 December 16; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nParker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We are deeply indebted to everyone who helped make the PSP mission possible. In particular, we thank all of the outstanding scientists, engineers, technicians, and administrative support people across all of the IS\u2299IS institutions that produced and supported the IS\u2299IS instrument suite and support its operations and the scientific analysis of its data. We also thank the FIELDS and SWEAP teams for cooperation. The IS\u2299IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). This research was partially supported by the Parker Solar Probe Plus project through Princeton/IS\u2299IS subcontract SUB0000165, and in part by NSF-SHINE AGS-1460130, NASA Heliospheric Guest Investigator grant No. 80NSSC19K0284, and grant RTA6280002 from Thailand Science Research and Innovation. S.D.B. acknowledges the support of the Leverhulme Trust Visiting Professorship program.\n\nPublished - pdf
Accepted Version - 1912.03424.pdf
",
"abstract": "Observations at 1 au have confirmed that enhancements in measured energetic-particle (EP) fluxes are statistically associated with \"rough\" magnetic fields, i.e., fields with atypically large spatial derivatives or increments, as measured by the Partial Variance of Increments (PVI) method. One way to interpret this observation is as an association of the EPs with trapping or channeling within magnetic flux tubes, possibly near their boundaries. However, it remains unclear whether this association is a transport or local effect; i.e., the particles might have been energized at a distant location, perhaps by shocks or reconnection, or they might experience local energization or re-acceleration. The Parker Solar Probe (PSP), even in its first two orbits, offers a unique opportunity to study this statistical correlation closer to the corona. As a first step, we analyze the separate correlation properties of the EPs measured by the Integrated Science Investigation of the Sun (IS\u2299IS) instruments during the first solar encounter. The distribution of time intervals between a specific type of event, i.e., the waiting time, can indicate the nature of the underlying process. We find that the IS\u2299IS observations show a power-law distribution of waiting times, indicating a correlated (non-Poisson) distribution. Analysis of low-energy (~15 \u2013 200 keV/nuc) IS\u2299IS data suggests that the results are consistent with the 1 au studies, although we find hints of some unexpected behavior. A more complete understanding of these statistical distributions will provide valuable insights into the origin and propagation of solar EPs, a picture that should become clear with future PSP orbits.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 61",
"id_number": "CaltechAUTHORS:20200203-092722125",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092722125",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "SUB0000165"
},
{
"agency": "NSF",
"grant_number": "AGS-1460130"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0284"
},
{
"agency": "Ministry of Higher Education, Science, Research and Innovation (Thailand)",
"grant_number": "RTA6280002"
},
{
"agency": "Leverhulme Trust"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4365/ab6220",
"primary_object": {
"basename": "1912.03424.pdf",
"url": "https://authors.library.caltech.edu/records/69xme-na075/files/1912.03424.pdf"
},
"related_objects": [
{
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/69xme-na075/files/pdf"
}
],
"pub_year": "2020",
"author_list": "Bandyopadhyay, Riddhi; Matthaeus, W. H.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vr2bs-atw39",
"eprint_id": 101075,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:51:13",
"lastmod": "2026-03-28 22:34:14",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"name": {
"family": "Malandraki",
"given": "O."
},
"orcid": "0000-0002-4751-6835"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R. L., Jr."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Posner",
"given": "A."
},
"orcid": "0000-0003-1572-8734"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
}
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Korreck",
"given": "K. E."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Livi",
"given": "R."
},
"orcid": "0000-0002-0396-0547"
},
{
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"name": {
"family": "Whittlesey",
"given": "P."
},
"orcid": "0000-0002-7287-5098"
},
{
"name": {
"family": "Poduval",
"given": "B."
},
"orcid": "0000-0003-1258-0308"
}
]
},
"title": "Observations of the 2019 April 4 Solar Energetic Particle Event at the Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "The Sun; Solar energetic particles",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 27; revised 2019 October 31; accepted 2019 November 11; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nThis work was supported by NASA under contract NNN06AA01C. Parker Solar Probe was designed, built, and is now operated by the Johns Hopkins University Applied Physics Laboratory as part of NASA's Living With a Star (LWS) program. Support from the LWS management and technical team has played a critical role in the success of this mission. We appreciate the contributions of the many individuals who have made PSP the successful mission that it is, in particular the EPI-Hi engineers W. R. Cook, B. Kecman, G. Dirks, and N. Angold. We gratefully acknowledge the test and calibration support provided by Michigan State University's National Superconducting Cyclotron Laboratory, Texas A&M University's Cyclotron Institute, and the Lawrence Berkeley National Laboratory's 88-inch Cyclotron Laboratory. The IS\u0298IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).We thank the GONG and Wilcox Solar Observatory teams for making their data readily accessible online. S.D.B. acknowledges the support of the Leverhulme Trust Visiting Professorship program.\n\nPublished - pdf
Accepted Version - 1912.03384.pdf
Supplemental Material - apjsab5712f10_video.mp4
",
"abstract": "A solar energetic particle event was detected by the Integrated Science Investigation of the Sun (IS\u2299IS) instrument suite on Parker Solar Probe (PSP) on 2019 April 4 when the spacecraft was inside of 0.17 au and less than 1 day before its second perihelion, providing an opportunity to study solar particle acceleration and transport unprecedentedly close to the source. The event was very small, with peak 1 MeV proton intensities of ~0.3 particles (cm\u00b2 sr s MeV)\u207b\u00b9, and was undetectable above background levels at energies above 10 MeV or in particle detectors at 1 au. It was strongly anisotropic, with intensities flowing outward from the Sun up to 30 times greater than those flowing inward persisting throughout the event. Temporal association between particle increases and small brightness surges in the extreme-ultraviolet observed by the Solar TErrestrial RElations Observatory, which were also accompanied by type III radio emission seen by the Electromagnetic Fields Investigation on PSP, indicates that the source of this event was an active region nearly 80\u00b0 east of the nominal PSP magnetic footpoint. This suggests that the field lines expanded over a wide longitudinal range between the active region in the photosphere and the corona.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 35",
"id_number": "CaltechAUTHORS:20200203-131825142",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-131825142",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Leverhulme Trust"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ab5712",
"primary_object": {
"basename": "1912.03384.pdf",
"url": "https://authors.library.caltech.edu/records/vr2bs-atw39/files/1912.03384.pdf"
},
"related_objects": [
{
"basename": "apjsab5712f10_video.mp4",
"url": "https://authors.library.caltech.edu/records/vr2bs-atw39/files/apjsab5712f10_video.mp4"
},
{
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/vr2bs-atw39/files/pdf"
}
],
"pub_year": "2020",
"author_list": "Leske, R. A.; Christian, E. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/rqvtg-4ve60",
"eprint_id": 101065,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:34",
"lastmod": "2026-03-29 21:46:30",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Desai-M-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Mitchell-D-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Szalay-J-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Roelof-E-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Giacalone-J",
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"id": "Hill-M-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "McComas-D-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Schwadron-N-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "McNutt-R-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Joyce-C-J",
"name": {
"family": "Joyce",
"given": "C."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Ebert-R-W",
"name": {
"family": "Ebert",
"given": "R. W."
},
"orcid": "0000-0002-2504-4320"
},
{
"id": "Dayeh-M-A",
"name": {
"family": "Dayeh",
"given": "M. A."
},
"orcid": "0000-0001-9323-1200"
},
{
"id": "Allen-R-C",
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"id": "Krimigis-S-M",
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Matthaeus-W-H",
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "Malandraki-O-E",
"name": {
"family": "Malandraki",
"given": "O."
},
"orcid": "0000-0002-4751-6835"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Bale-S-D",
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"id": "Pulupa-M",
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"id": "MacDowall-R-J",
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"id": "Kasper-J-C",
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
}
]
},
"title": "Properties of Suprathermal-through-energetic He Ions Associated with Stream Interaction Regions Observed over the Parker Solar Probe's First Two Orbits",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar wind; Corotating streams; Interplanetary particle acceleration",
"note": "\u00a9 2020. The Author(s). Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2019 December 6; revised 2019 December 27; accepted 2019 December 27; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nThis work was supported by NASA's Parker Solar Probe Mission, contract NNN06AA01C. We thank all the scientists and engineers who have worked hard to make PSP a successful mission, in particular the engineers, scientists, and administrators who designed and built IS\u2299IS/EPI-Lo, IS\u2299IS/EPI-Hi, FIELDS, and SWEAP instrument suites and support their operations and the scientific analysis of its data. For their contributions to the scientific configuration and instrumental analysis, we owe special thanks to P. Kollmann, J. Peachy, and J. Vandegriff at JHU/APL for EPI-Lo and B. Kecman and W. R. Cook at Caltech for EPI-Hi. The IS\u2299IS data are available at http://spp-isois.sr.unh.edu/data_public/, as well as at the NASA Space Physics Data Facility. Work at SwRI is also supported in part under NASA grants 80NSSC17K0009, NNX15AG09G, 80NSSC18K0520, NNX17AI17G, 80NSSC19K0079, and NNX13AI75G. S.D.B. acknowledges support of the Leverhulme Trust Visiting Professorship program.\n\nPublished - pdf
",
"abstract": "The Integrated Science Investigation of the Sun (IS\u2299IS) suite on board NASA's Parker Solar Probe (PSP) observed six distinct enhancements in the intensities of suprathermal-through-energetic (~0.03\u20133 MeV nucleon\u207b\u00b9) He ions associated with corotating or stream interaction regions (CIR or SIR) during its first two orbits. Our results from a survey of the time histories of the He intensities, spectral slopes, and anisotropies and the event-averaged energy spectra during these events show the following: (1) In the two strongest enhancements, seen at 0.35 and 0.85 au, the higher-energy ions arrive and maximize later than those at lower energies. In the event seen at 0.35 au, the He ions arrive when PSP was away from the SIR trailing edge and entered the rarefaction region in the high-speed stream. (2) The He intensities either are isotropic or show sunward anisotropies in the spacecraft frame. (3) In all events, the energy spectra between ~0.2 and 1 MeV nucleon\u207b\u00b9 are power laws of the form \u221dE\u207b\u00b2. In the two strongest events, the energy spectra are well represented by flat power laws between ~0.03 and 0.4 MeV nucleon\u207b\u00b9 modulated by exponential rollovers between ~0.4 and 3 MeV nucleon\u207b\u00b9. We conclude that the SIR-associated He ions originate from sources or shocks beyond PSP's location rather than from acceleration processes occurring at nearby portions of local compression regions. Our results also suggest that rarefaction regions that typically follow the SIRs facilitate easier particle transport throughout the inner heliosphere such that low-energy ions do not undergo significant energy loss due to adiabatic deceleration, contrary to predictions of existing models.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 56",
"id_number": "CaltechAUTHORS:20200203-092721940",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092721940",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0009"
},
{
"agency": "NASA",
"grant_number": "NNX15AG09G"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0520"
},
{
"agency": "NASA",
"grant_number": "NNX17AI17G"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0079"
},
{
"agency": "NASA",
"grant_number": "NNX13AI75G"
},
{
"agency": "Leverhulme Trust"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4365/ab65ef",
"primary_object": {
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/rqvtg-4ve60/files/pdf"
},
"pub_year": "2020",
"author_list": "Desai, M. I.; Mitchell, D. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/thaks-ave64",
"eprint_id": 101060,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:07",
"lastmod": "2026-03-29 20:39:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Schwadron-N-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Bale",
"given": "S."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Bonnell",
"given": "J."
}
},
{
"name": {
"family": "Case",
"given": "A."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"name": {
"family": "Dudok de Wit",
"given": "T."
},
"orcid": "0000-0002-4401-0943"
},
{
"name": {
"family": "de Wet",
"given": "W."
}
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Goetz",
"given": "K."
}
},
{
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Goerby",
"given": "M."
}
},
{
"name": {
"family": "Harvey",
"given": "P."
}
},
{
"name": {
"family": "Heber",
"given": "B."
},
"orcid": "0000-0003-0960-5658"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Karavolos",
"given": "M."
}
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Korreck",
"given": "K."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Larson",
"given": "D."
}
},
{
"name": {
"family": "Livi",
"given": "R."
}
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "Malandraki",
"given": "O."
}
},
{
"name": {
"family": "MacDowall",
"given": "R."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Malaspina",
"given": "D."
},
"orcid": "0000-0003-1191-1558"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R. L., Jr."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Mays",
"given": "L."
}
},
{
"name": {
"family": "Niehof",
"given": "J. T."
}
},
{
"name": {
"family": "Odstrcil",
"given": "D."
}
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Poduval",
"given": "B."
}
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
}
},
{
"name": {
"family": "Stevens",
"given": "M."
},
"orcid": "0000-0002-7728-0085"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Winslow",
"given": "R."
}
},
{
"name": {
"family": "Whittlesey",
"given": "P."
}
}
]
},
"title": "Seed Population Preconditioning and Acceleration Observed by the Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar wind; Solar energetic particles; Solar coronal mass ejections",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 13; revised 2019 November 4; accepted 2019 November 5; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nWe are deeply indebted to everyone who helped make the Parker Solar Probe (PSP) mission possible. We thank all of the outstanding scientists, engineers, technicians, and administrative support people across all of the IS\u2299IS, FIELDS, and SWEAP institutions that produced and supported the IS\u2299IS, FIELDS, and SWEAP instrument suites, support its operations and the scientific analysis of its data. This work was supported as a part of the PSP mission under contract NNN06AA01C. The IS\u0298IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/). Parker Solar Probe was designed, built, and is now operatedby the Johns Hopkins Applied Physics Laboratory aspart of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. We thank and acknowledge Dr. X.P. Zhao for providing the CSSS model.\n\nPublished - pdf
Supplemental Material - apjsab5527f13_video.mp4
",
"abstract": "A series of solar energetic particle (SEP) events was observed by the Integrated Science Investigation of the Sun (IS\u2299IS) on the Parker Solar Probe (PSP) during the period from 2019 April 18 through 24. The PSP spacecraft was located near 0.48 au from the Sun on Parker spiral field lines that projected out to 1 au within ~25\u00b0 of the near-Earth spacecraft. These SEP events, though small compared to historically large SEP events, were among the largest observed thus far in the PSP mission and provide critical information about the space environment inside 1 au during SEP events. During this period, the Sun released multiple coronal mass ejections (CMEs). One of these CMEs observed was initiated on 2019 April 20 at 01:25 UTC, and the interplanetary CME (ICME) propagated out and passed over the PSP spacecraft. Observations by the Electromagnetic Fields Investigation show that the magnetic field structure was mostly radial throughout the passage of the compression region and the plasma that followed, indicating that PSP did not directly observe a flux rope internal to the ICME, consistent with the location of PSP on the ICME flank. Analysis using relativistic electrons observed near Earth by the Electron, Proton and Alpha Monitor on the Advanced Composition Explorer demonstrates the presence of electron seed populations (40\u2013300 keV) during the events observed. The energy spectrum of the IS\u2299IS-observed proton seed population below 1 MeV is close to the limit of possible stationary-state plasma distributions out of equilibrium. IS\u2299IS observations reveal the enhancement of seed populations during the passage of the ICME, which likely indicates a key part of the preacceleration process that occurs close to the Sun.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 33",
"id_number": "CaltechAUTHORS:20200203-092721301",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092721301",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4365/ab5527",
"primary_object": {
"basename": "apjsab5527f13_video.mp4",
"url": "https://authors.library.caltech.edu/records/thaks-ave64/files/apjsab5527f13_video.mp4"
},
"related_objects": [
{
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/thaks-ave64/files/pdf"
}
],
"pub_year": "2020",
"author_list": "Schwadron, N. A.; Bale, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ztyav-dyx73",
"eprint_id": 101067,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:46",
"lastmod": "2026-03-30 05:33:19",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hill-M-E",
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"id": "Mitchell-D-G",
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"id": "Allen-R-C",
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"id": "de-Nolfo-G-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Vourlidas-A",
"name": {
"family": "Vourlidas",
"given": "A."
},
"orcid": "0000-0002-8164-5948"
},
{
"id": "Brown-L-E",
"name": {
"family": "Brown",
"given": "L. E."
}
},
{
"id": "Jones-S-I",
"name": {
"family": "Jones",
"given": "S. I."
},
"orcid": "0000-0001-9498-460X"
},
{
"id": "McComas-D-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "McNutt-R-L-Jr",
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mitchell-J-G",
"name": {
"family": "Mitchell",
"given": "J. G."
},
"orcid": "0000-0003-4501-5452"
},
{
"id": "Szalay-J-R",
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"id": "Wallace-S",
"name": {
"family": "Wallace",
"given": "S."
},
"orcid": "0000-0002-1091-4688"
},
{
"id": "Arge-C-N",
"name": {
"family": "Arge",
"given": "C. N."
}
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Crew-A-B",
"name": {
"family": "Crew",
"given": "A. B."
},
"orcid": "0000-0002-7493-2682"
},
{
"id": "Desai-M-I",
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"id": "Giacalone-J",
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"id": "Henney-C-J",
"name": {
"family": "Henney",
"given": "C. J."
},
"orcid": "0000-0002-6038-6369"
},
{
"id": "Joyce-C-J",
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Krimigis-S-M",
"name": {
"family": "Krimigis",
"given": "S. M."
},
"orcid": "0000-0003-2781-2386"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Nelson-K-S",
"name": {
"family": "Nelson",
"given": "K. S."
},
"orcid": "0000-0003-3807-4518"
},
{
"id": "Roelof-E-C",
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"id": "Schwadron-N-A",
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Small, Low-energy, Dispersive Solar Energetic Particle Events Observed by Parker Solar Probe",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "The Sun; Interplanetary particle acceleration; Solar energetic particles; Space vehicle instruments; Solar flares; Michelson interferometers; Solar extreme ultraviolet emission; Solar filament eruptions; Quiet Sun; Solar telescopes; Solar coronal mass ejections; Space probes",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 October 4; revised 2019 November 15; accepted 2019 November 17; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nThis work was supported by NASA's Parker Solar Probe mission, contract NNN06AA01C. We are indebted to the exceptional, dedicated efforts of those who have made this mission and this experiment possible, in particular the engineers, scientist, and administrators who designed and built EPI-Lo. P. Kollmann, J. Peachy, and J. Vandegriff (at JHU/APL) are owed special thanks for their contribution to the scientific configuration and instrumental analysis of EPI-Lo. STEREO work is supported by NASA grant 80NSSC19K1261 (A.V.). This work utilizes data produced collaboratively between Air Force Research Laboratory (AFRL) and the National Solar Observatory. The ADAPT model development is supported by AFRL. The IS\u2299IS data and visualization tools are available to the community at https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - pdf
",
"abstract": "The Energetic Particle Instrument\u2013Low Energy (EPI-Lo) experiment has detected several weak, low-energy (~30\u2013300 keV nucleon\u207b\u00b9) solar energetic particle (SEP) events during its first two closest approaches to the Sun, providing a unique opportunity to explore the sources of low-energy particle acceleration. As part of the Parker Solar Probe (PSP) Integrated Science Investigation of the Sun (IS\u2299IS) suite, EPI-Lo was designed to investigate the physics of energetic particles; however, in the special lowest-energy \"time-of-flight only\" product used in this study, it also responds to solar photons in a subset of approximately sunward-looking apertures lacking special light-attenuating foils. During the first three perihelia, in a frame rotating with the Sun, PSP undergoes retrograde motion, covering a 17\u00b0 heliographic longitudinal range three times during the course of the ~11-day perihelion passes, permitting a unique spatial and temporal study into the location, correlation, and persistence of previously unmeasurable SEPs. We examine the signatures of these SEPs (during the first PSP perihelion pass only) and the connection to possible solar sources using remote observations from the Solar Dynamics Observatory (SDO), the Solar TErrestrial RElations Observatory (STEREO), and the ground-based Global Oscillation Network Group (GONG). The orientation of the Sun relative to STEREO, SDO, and GONG makes such identifications challenging, but we do have several candidates, including an equatorial coronal hole at a Carrington longitude of ~335\u00b0. To analyze observations from EPI-Lo, which is a new type of particle instrument, we examine instrumental effects and provide a preliminary separation of the ion signal from the photon background.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 65",
"id_number": "CaltechAUTHORS:20200203-092722235",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092722235",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K1261"
},
{
"agency": "Air Force Research Laboratory (AFRL)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4365/ab643d",
"primary_object": {
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/ztyav-dyx73/files/pdf"
},
"pub_year": "2020",
"author_list": "Hill, M. E.; Mitchell, D. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vqhhf-dwe11",
"eprint_id": 101059,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:00",
"lastmod": "2026-03-29 14:54:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Giacalone-J",
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "McNutt",
"given": "R. L., Jr."
}
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Rouillard",
"given": "A. P."
}
},
{
"name": {
"family": "Kouloumvakos",
"given": "A."
}
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Bale",
"given": "S."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Brown",
"given": "L. E."
}
},
{
"name": {
"family": "Case",
"given": "A."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Chen",
"given": "X."
}
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Joyce",
"given": "C."
},
"orcid": "0000-0002-3841-5020"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Klein",
"given": "K. G."
}
},
{
"name": {
"family": "Korreck",
"given": "K."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Larson",
"given": "D. E."
}
},
{
"name": {
"family": "Livi",
"given": "R."
}
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Nieves-Chinchilla",
"given": "T."
},
"orcid": "0000-0003-0565-4890"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
}
},
{
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"name": {
"family": "Szabo",
"given": "A."
},
"orcid": "0000-0003-3255-9071"
},
{
"name": {
"family": "Whittlesey",
"given": "P. L."
}
}
]
},
"title": "Solar Energetic Particles Produced by a Slow Coronal Mass Ejection at \u223c0.25 au",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Interplanetary particle acceleration; Interplanetary shocks",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 September 12; revised 2019 October 24; accepted 2019 October 27; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nParker Solar Probe was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. J.G. acknowledges useful conversations about the Parker transport equation with J. Kota and F. Fraschetti. A.K. and A.P.R. acknowledge financial support from the ANR project COROSHOCK ANR-17-CE31-0006-01 and from the ERC project SLOW_SOURCE\u2014DLV-819189. We thank Jon Linker and Pete Riley of Predictive Sciences for providing the background solar wind model exploited in this study. The STA/C2 images, which were analyzed for results presented in this paper, were obtained from the STEREO science center.\n\nPublished - pdf
",
"abstract": "We present an analysis of Parker Solar Probe (PSP) IS\u2299IS observations of ~30\u2013300 keV n\u207b\u00b9 ions on 2018 November 11 when PSP was about 0.25 au from the Sun. Five hours before the onset of a solar energetic particle (SEP) event, a coronal mass ejection (CME) was observed by STEREO-A/COR2, which crossed PSP about a day later. No shock was observed locally at PSP, but the CME may have driven a weak shock earlier. The SEP event was dispersive, with higher energy ions arriving before the lower energy ones. Timing suggests the particles originated at the CME when it was at ~7.4R_\u2299. SEP intensities increased gradually from their onset over a few hours, reaching a peak, and then decreased gradually before the CME arrived at PSP. The event was weak, having a very soft energy spectrum (\u22124 to \u22125 spectral index). The earliest arriving particles were anisotropic, moving outward from the Sun, but later, the distribution was observed to be more isotropic. We present numerical solutions of the Parker transport equation for the transport of 30\u2013300 keV n\u207b\u00b9 ions assuming a source comoving with the CME. Our model agrees well with the observations. The SEP event is consistent with ion acceleration at a weak shock driven briefly by the CME close to the Sun, which later dissipated before arriving at PSP, followed by the transport of ions in the interplanetary magnetic field.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 29",
"id_number": "CaltechAUTHORS:20200203-092721189",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092721189",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Agence Nationale pour la Recherche (ANR)",
"grant_number": "ANR-17-CE31-0006-01"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "819189"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ab5221",
"primary_object": {
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/vqhhf-dwe11/files/pdf"
},
"pub_year": "2020",
"author_list": "Giacalone, J.; Mitchell, D. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7mnh4-v1608",
"eprint_id": 101062,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:14",
"lastmod": "2026-03-30 05:04:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Allen-R-C",
"name": {
"family": "Allen",
"given": "R. C."
},
"orcid": "0000-0003-2079-5683"
},
{
"name": {
"family": "Lario",
"given": "D."
},
"orcid": "0000-0002-3176-8704"
},
{
"name": {
"family": "Odstrcil",
"given": "D."
}
},
{
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
},
{
"name": {
"family": "Jian",
"given": "L. K."
},
"orcid": "0000-0002-6849-5527"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Badman",
"given": "S. T."
},
"orcid": "0000-0002-6145-436X"
},
{
"name": {
"family": "Jones",
"given": "S. I."
},
"orcid": "0000-0001-9498-460X"
},
{
"name": {
"family": "Arge",
"given": "C. N."
}
},
{
"name": {
"family": "Mays",
"given": "M. L."
},
"orcid": "0000-0001-9177-8405"
},
{
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Bonnell",
"given": "J. W."
}
},
{
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"name": {
"family": "Dudok de Wit",
"given": "T."
},
"orcid": "0000-0002-4401-0943"
},
{
"name": {
"family": "Goetz",
"given": "K."
},
"orcid": "0000-0003-0420-3633"
},
{
"name": {
"family": "Harvey",
"given": "P. R."
},
"orcid": "0000-0002-6938-0166"
},
{
"name": {
"family": "Henney",
"given": "C. J."
},
"orcid": "0000-0002-6038-6369"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Korreck",
"given": "K. E."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Larson",
"given": "D."
},
"orcid": "0000-0001-5030-6030"
},
{
"name": {
"family": "Livi",
"given": "R."
},
"orcid": "0000-0002-0396-0547"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Malaspina",
"given": "D. M."
},
"orcid": "0000-0003-1191-1558"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R."
},
"orcid": "0000-0002-4722-9166"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Raouafi",
"given": "N."
},
"orcid": "0000-0003-2409-3742"
},
{
"name": {
"family": "Schwadron",
"given": "N."
},
"orcid": "0000-0002-3737-9283"
},
{
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
},
{
"name": {
"family": "Whittlesey",
"given": "P. L."
},
"orcid": "0000-0002-7287-5098"
},
{
"name": {
"family": "Wiedenbeck",
"given": "M."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Solar Wind Streams and Stream Interaction Regions Observed by the Parker Solar Probe with Corresponding Observations at 1 au",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Fast solar wind; Heliosphere; Interplanetary particle acceleration",
"note": "\u00a9 2020. The American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2019 September 15; revised 2019 October 19; accepted 2019 October 21; published 2020 February 3.\n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nThis work was supported under NASA contract NNN06AA01C. The ACE data are publicly available at the ACE mission website: http://www.srl.caltech.edu/ACE/. The STEREO SEPT data are available at http://www2.physik.uni-kiel.de/stereo/data/sept/, and STEREO magnetic field and plasma data can be found at the STEREO Science Center: https://stereo-ssc.nascom.nasa.gov. Wind data are available at https://cdaweb.gsfc.nasa.gov/. The authors would like to thank the Parker Solar Probe instrument teams for the years of work and preparation needed to allow for the new and exciting studies in this special issue and those that will be appearing for years to come. S.D.B. acknowledges the support of the Leverhulme Trust Visiting Professorship program. This work utilizes data produced collaboratively between the Air Force Research Laboratory (AFRL) and the National Solar Observatory. The ADAPT model development is supported by AFRL.\n\nPublished - pdf
",
"abstract": "Several fast solar wind streams and stream interaction regions (SIRs) were observed by the Parker Solar Probe (PSP) during its first orbit (2018 September\u20132019 January). During this time, several recurring SIRs were also seen at 1 au at both L1 (Advanced Composition Explorer (ACE) and Wind) and the location of the Solar Terrestrial Relations Observatory-Ahead (STEREO-A). In this paper, we compare four fast streams observed by PSP at different radial distances during its first orbit. For three of these fast stream events, measurements from L1 (ACE and Wind) and STEREO-A indicated that the fast streams were observed by both PSP and at least one of the 1 au monitors. Our associations are supported by simulations made by the ENLIL model driven by GONG-(ADAPT-)WSA, which allows us to contextualize the inner heliospheric conditions during the first orbit of PSP. Additionally, we determine which of these fast streams are associated with an SIR and characterize the SIR properties for these events. From these comparisons, we find that the compression region associated with the fast-speed streams overtaking the preceding solar wind can form at various radial distances from the Sun in the inner heliosphere inside 0.5 au, with the suprathermal ion population (energies between 30 and 586 keV) observed as isolated enhancements suggesting localized acceleration near the SIR stream interface at ~0.3 au, which is unlike those seen at 1 au, where the suprathermal enhancements extend throughout and behind the SIR. This suprathermal enhancement extends further into the fast stream with increasing distance from the Sun.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 36",
"id_number": "CaltechAUTHORS:20200203-092721505",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092721505",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Air Force Research Laboratory (AFRL)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/ab578f",
"primary_object": {
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/7mnh4-v1608/files/pdf"
},
"pub_year": "2020",
"author_list": "Allen, R. C.; Lario, D.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/sbf8x-a1b82",
"eprint_id": 101064,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:50:28",
"lastmod": "2026-03-28 20:14:07",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"name": {
"family": "Bu\u010dik",
"given": "R."
},
"orcid": "0000-0001-7381-6949"
},
{
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"name": {
"family": "Ho",
"given": "G. C."
},
"orcid": "0000-0003-1093-2066"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"name": {
"family": "Desai",
"given": "M. I."
},
"orcid": "0000-0002-7318-6008"
},
{
"name": {
"family": "Giacalone",
"given": "J."
}
},
{
"name": {
"family": "Haggerty",
"given": "D. K."
},
"orcid": "0000-0001-6395-8943"
},
{
"name": {
"family": "Hill",
"given": "M. E."
},
"orcid": "0000-0002-5674-4936"
},
{
"name": {
"family": "Joyce",
"given": "C. J."
},
"orcid": "0000-0002-3841-5020"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"name": {
"family": "Malandraki",
"given": "O."
},
"orcid": "0000-0002-4751-6835"
},
{
"name": {
"family": "Matthaeus",
"given": "W. H."
},
"orcid": "0000-0001-7224-6024"
},
{
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"name": {
"family": "McNutt",
"given": "R. L., Jr."
},
"orcid": "0000-0002-4722-9166"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"name": {
"family": "Mitchell",
"given": "D. G."
},
"orcid": "0000-0003-1960-2119"
},
{
"name": {
"family": "Posner",
"given": "A."
},
"orcid": "0000-0003-1572-8734"
},
{
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"name": {
"family": "Roelof",
"given": "E. C."
},
"orcid": "0000-0002-2270-0652"
},
{
"name": {
"family": "Schwadron",
"given": "N. A."
},
"orcid": "0000-0002-3737-9283"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"name": {
"family": "Szalay",
"given": "J. R."
},
"orcid": "0000-0003-2685-9801"
},
{
"name": {
"family": "Bale",
"given": "S. D."
},
"orcid": "0000-0002-1989-3596"
},
{
"name": {
"family": "Case",
"given": "A. W."
},
"orcid": "0000-0002-3520-4041"
},
{
"name": {
"family": "Kasper",
"given": "J. C."
},
"orcid": "0000-0002-7077-930X"
},
{
"name": {
"family": "Korreck",
"given": "K. E."
},
"orcid": "0000-0001-6095-2490"
},
{
"name": {
"family": "Larson",
"given": "D. E."
},
"orcid": "0000-0001-5030-6030"
},
{
"name": {
"family": "MacDowall",
"given": "R. J."
},
"orcid": "0000-0003-3112-4201"
},
{
"name": {
"family": "Pulupa",
"given": "M."
},
"orcid": "0000-0002-1573-7457"
},
{
"name": {
"family": "Stevens",
"given": "M. L."
},
"orcid": "0000-0002-7728-0085"
}
]
},
"title": "\u00b3He-rich Solar Energetic Particle Observations at the Parker Solar Probe and near Earth",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Solar energetic particles; Solar activity; Solar x-ray flares",
"note": "\u00a9 2020. The American Astronomical Society. \n\nReceived 2019 October 6; revised 2019 October 29; accepted 2019 October 30; published 2020 February 3. \n\nEarly Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration \n\nWe thank the large team of people responsible for developing the IS\u2609IS instruments and, particularly, the lead IS\u2609IS/EPI-Hi engineers, including Rick Cook, Branislav Kecman, Greg Dirks, and Nigel Angold. We gratefully acknowledge the test and calibration support provided by Michigan State University's National Superconducting Cyclotron Laboratory, Texas A&M University's Cyclotron Institute, and the Lawrence Berkeley National Laboratory's 88-inch Cyclotron Laboratory. PSP was designed, built, and is now operated by the Johns Hopkins Applied Physics Laboratory as part of NASA's Living with a Star (LWS) program (contract NNN06AA01C). Support from the LWS management and technical team has played a critical role in the success of the Parker Solar Probe mission. This study benefited from discussions within the International Space Science Institute (ISSI) team on \"Origins of \u00b3He-Rich Solar Energetic Particles.\" The ACE work was supported under NASA grant 80NSSC18K0223, and the PSP work was supported under NASA contract NNN06AA01C. The work of R.B. was supported by DFG grant BU 3115/4-1. S.D.B. acknowledges the support of the Leverhulme Trust Visiting Professorship program. \n\nThe IS\u2609IS data and visualization tools are available to the community at: https://spacephysics.princeton.edu/missions-instruments/isois; data are also available via the NASA Space Physics Data Facility (https://spdf.gsfc.nasa.gov/).\n\nPublished - pdf
Supplemental Material - apjsab5963f11_video.mp4
",
"abstract": "The Integrated Science Investigation of the Sun (IS\u2299IS) instrument suite on the Parker Solar Probe (PSP) spacecraft is making in situ observations of energetic ions and electrons closer to the Sun than any previous mission. Using data collected during its first two orbits, which reached perihelion distances of 0.17 au, we have searched for \u00b3He-rich solar energetic particle (SEP) events under very quiet solar minimum conditions. On 2019-110\u2013111 (April 20\u201321), \u00b3He-rich SEPs were observed at energies near 1 MeV nucleon \u207b\u00b9 in association with energetic protons, heavy ions, and electrons. This activity was also detected by the Ultra-Low-Energy Isotope Spectrometer and the Electron, Proton, and Alpha Monitor instruments on the Advanced Composition Explorer (ACE) spacecraft located near Earth, 0.99 au from the Sun. At that time, PSP and ACE were both magnetically connected to locations near the west limb of the Sun. Remote sensing measurements showed the presence of type III radio bursts and also helical jets from this region of the Sun. This combination of observations is commonly associated with \u00b3He-rich SEP acceleration on the Sun. AR 12738, which was located at Carrington coordinates from which numerous X-ray flares were observed over a period of more than 6 months, was identified as the source of the \u00b3He-rich events. This region was also the source of several other SEP events detected at PSP or ACE. Aside from the period in 2019 April, IS\u2299IS did not observe any other \u00b3He-rich SEPs during orbits 1 and 2.",
"date": "2020-02",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "246",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 42",
"id_number": "CaltechAUTHORS:20200203-092721818",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092721818",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0223"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "BU 3115/4-1"
},
{
"agency": "Leverhulme Trust"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4365/ab5963",
"primary_object": {
"basename": "apjsab5963f11_video.mp4",
"url": "https://authors.library.caltech.edu/records/sbf8x-a1b82/files/apjsab5963f11_video.mp4"
},
"related_objects": [
{
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/sbf8x-a1b82/files/pdf"
}
],
"pub_year": "2020",
"author_list": "Wiedenbeck, M. E.; Bu\u010dik, R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/69c5v-hg726",
"eprint_id": 100829,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:40:10",
"lastmod": "2026-03-30 14:19:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Fryer-C-L",
"name": {
"family": "Fryer",
"given": "C. L."
},
"orcid": "0000-0003-2624-0056"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Lopez-L-A",
"name": {
"family": "Lopez",
"given": "L. A."
},
"orcid": "0000-0002-1790-3148"
},
{
"id": "Reynolds-S",
"name": {
"family": "Reynolds",
"given": "S."
},
"orcid": "0000-0002-5365-5444"
},
{
"id": "Zoglauer-A",
"name": {
"family": "Zoglauer",
"given": "A."
},
"orcid": "0000-0001-9067-3150"
}
]
},
"title": "NuSTAR Observations of G11.2\u20130.3",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Rotation powered pulsars; Supernova remnants; Single X-ray stars; X-ray stars",
"note": "\u00a9 2020 The American Astronomical Society. \n\nReceived 2019 April 4; revised 2019 October 31; accepted 2019 November 4; published 2020 January 21. \n\nThis work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We would also like to thank Robert Archibald for his help with finding the timing solution. \n\nFacility: NuSTAR Chandra INTEGRAL - .\n\nPublished - Madsen_2020_ApJ_889_23.pdf
Accepted Version - 2002.12775.pdf
",
"abstract": "We present in this paper the hard X-ray view of the pulsar wind nebula in G11.2\u22120.3 and its central pulsar powered pulsar J1811\u22121925 as seen by NuSTAR. We complement the data with Chandra for a more complete picture and confirm the existence of a hard, power-law component in the shell with photon index \u0393 = 2.1 \u00b1 0.1, which we attribute to synchrotron emission. Our imaging observations of the shell show a slightly smaller radius at higher energies, consistent with Chandra results, and we find shrinkage as a function of increased energy along the jet direction, indicating that the electron outflow in the PWN may be simpler than that seen in other young PWNe. Combining NuSTAR with INTEGRAL, we find that the pulsar spectrum can be fit by a power law with \u0393 = 1.32 \u00b1 0.07 up to 300 keV without evidence of curvature.",
"date": "2020-01-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "889",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 23",
"id_number": "CaltechAUTHORS:20200122-085827125",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200122-085827125",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab54ca",
"primary_object": {
"basename": "2002.12775.pdf",
"url": "https://authors.library.caltech.edu/records/69c5v-hg726/files/2002.12775.pdf"
},
"related_objects": [
{
"basename": "Madsen_2020_ApJ_889_23.pdf",
"url": "https://authors.library.caltech.edu/records/69c5v-hg726/files/Madsen_2020_ApJ_889_23.pdf"
}
],
"pub_year": "2020",
"author_list": "Madsen, K. K.; Fryer, C. L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/djp6e-qb369",
"eprint_id": 100924,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:40:46",
"lastmod": "2026-03-30 06:20:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
}
]
},
"title": "Spectral Evolution of the Ultraluminous X-Ray Sources M82 X-1 and X-2",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astrophysical black holes; Intermediate-mass black holes; Stellar mass black holes; X-ray point sources; X-ray sources; Pulsars; Neutron\nstars",
"note": "\u00a9 2020 The Author(s). Published by IOP Publishing Ltd on behalf of the American Astronomical Society. \n\nReceived 2019 September 18; revised 2019 December 5; accepted 2019 December 15; published 2020 January 27. \n\nThis research has made use of data obtained with NuSTAR, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). Support for this work was provided by the National Aeronautics and Space Administration through Chandra Award Number GO6-17080X issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application package ciao. We also acknowledge the use of public data from the Swift data archive. D.J.W. acknowledges support from an STFC Ernest Rutherford Fellowship. \n\nFacilities: Chandra (ACIS) - , NuSTAR - , Swift (XRT). -\n\nPublished - Brightman_2020_ApJ_889_71.pdf
Submitted - 2001.07285.pdf
",
"abstract": "M82 hosts two well-known ultraluminous X-ray sources (ULXs). X-1, an intermediate-mass black hole (IMBH) candidate, and X-2, an ultraluminous X-ray pulsar. Here, we present a broadband X-ray spectral analysis of both sources based on 10 simultaneous observations made with Chandra and NuSTAR. Chandra provides the high spatial resolution to resolve the crowded field in the 0.5\u20138 keV band, and NuSTAR provides the sensitive hard X-ray spectral data, extending the bandpass of our study above 10 keV. These observations, taken in 2015\u20132016, cover a period of flaring from X-1, allowing us to study the spectral evolution of this source with luminosity. During four of these observations, X-2 was found to be at a low flux level, allowing an unambiguous view of the emission from X-1. We find that the broadband X-ray emission from X-1 is consistent with that seen in other ULXs observed in detail with NuSTAR, with a spectrum that includes a broadened disk-like component and a high-energy tail. We find that the luminosity of the disk scales with inner disk temperature as L \u221d T^(\u22123/2), contrary to expectations of a standard accretion disk and previous results. These findings rule out a thermal state for sub-Eddington accretion, and therefore do not support M82 X-1 as an IMBH candidate. We also find evidence that the neutral column density of the material in the line of sight increases with L_X, perhaps due to an increased mass outflow with accretion rate. For X-2, we do not find any significant spectral evolution, but we find the spectral parameters of the phase-averaged broadband emission are consistent with the pulsed emission at the highest X-ray luminosities.",
"date": "2020-01-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "889",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 71",
"id_number": "CaltechAUTHORS:20200127-074253356",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200127-074253356",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "GO6-17080X"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab629a",
"primary_object": {
"basename": "2001.07285.pdf",
"url": "https://authors.library.caltech.edu/records/djp6e-qb369/files/2001.07285.pdf"
},
"related_objects": [
{
"basename": "Brightman_2020_ApJ_889_71.pdf",
"url": "https://authors.library.caltech.edu/records/djp6e-qb369/files/Brightman_2020_ApJ_889_71.pdf"
}
],
"pub_year": "2020",
"author_list": "Brightman, Murray; Walton, Dominic J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zbnkg-1pe13",
"eprint_id": 100459,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:21:16",
"lastmod": "2026-03-31 05:55:54",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kamraj-N",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Assef-R-J",
"name": {
"family": "Assef",
"given": "Roberto J."
},
"orcid": "0000-0002-9508-3667"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "Michael J."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "Kyuseok"
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "The Broadband X-Ray Spectrum of the X-Ray-obscured Type 1 AGN 2MASX J193013.80+341049.5",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Active galactic nuclei; Seyfert galaxies; X-ray astronomy",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 September 19; revised 2019 November 4; accepted 2019 November 13; published 2019 December 26. \n\nWe have made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). M.B. acknowledges support from the Black Hole Initiative at Harvard University, through a grant from the John Templeton Foundation. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. D.J.W. acknowledges support from STFC in the form of an Ernest Rutherford fellowship. R.J.A was supported by FONDECYT grant No. 1191124. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift - , XMM-Newton - , Palomar DBSP. - \n\nSoftware: NuSTARDAS (v2.14.1), HEASOFT (v6.24), XMM SAS (v16.1.0), XSPEC (v12.8.2), Astropy, SciPy, NumPy, Matplotlib.\n\nPublished - Kamraj_2019_ApJ_887_255.pdf
Accepted Version - 1911.05820.pdf
",
"abstract": "We present results from modeling the broadband X-ray spectrum of the Type 1 active galactic nucleus (AGN) 2MASX J193013.80+341049.5 using NuSTAR, Swift, and archival XMM-Newton observations. We find this source to be highly X-ray obscured, with column densities exceeding 10\u00b2\u00b3 cm\u207b\u00b2 across all epochs of X-ray observations, spanning an 8 yr period. However, the source exhibits prominent broad optical emission lines, consistent with an unobscured Type 1 AGN classification. We fit the X-ray spectra with both phenomenological reflection models and physically motivated torus models to model the X-ray absorption. We examine the spectral energy distribution of this source and investigate some possible scenarios to explain the mismatch between X-ray and optical classifications. We compare the ratio of reddening to X-ray absorbing column density (E_(B\u2212V)/N_H) and find that 2MASX J193013.80+341049.5 likely has a much lower dust-to-gas ratio relative to the Galactic interstellar medium, suggesting that the broad line region itself could provide the source of extra X-ray obscuration, being composed of low-ionization, dust-free gas.",
"date": "2019-12-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "887",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 255",
"id_number": "CaltechAUTHORS:20200102-123811313",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200102-123811313",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Harvard University"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1191124"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab57fc",
"primary_object": {
"basename": "1911.05820.pdf",
"url": "https://authors.library.caltech.edu/records/zbnkg-1pe13/files/1911.05820.pdf"
},
"related_objects": [
{
"basename": "Kamraj_2019_ApJ_887_255.pdf",
"url": "https://authors.library.caltech.edu/records/zbnkg-1pe13/files/Kamraj_2019_ApJ_887_255.pdf"
}
],
"pub_year": "2019",
"author_list": "Kamraj, Nikita; Balokovi\u0107, Mislav; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0c97f-h2t19",
"eprint_id": 98275,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:18:23",
"lastmod": "2023-10-18 17:12:45",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-Alan-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-Andrew-J",
"name": {
"family": "Davis",
"given": "A. J."
},
"orcid": "0000-0002-9922-8915"
},
{
"id": "Labrador-Allan-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
}
]
},
"title": "Probing the energetic particle environment near the Sun",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Particle astrophysics; Solar physics",
"note": "\u00a9 2019 Springer Nature Limited. \n\nReceived 28 June 2019; Accepted 05 September 2019; Published 04 December 2019. \n\nWe are indebted to everyone who helped make the PSP mission possible. In particular, we thank all of the scientists, engineers, technicians, and administrative support people across all of the IS\u2609IS institutions that produced and supported the IS\u2609IS instrument suite and support its operations and the scientific analysis of its data. This work was supported as a part of the PSP mission under contract NNN06AA01C. S.D.B. acknowledges the support of the Leverhulme Trust Visiting Professorship programme and A.P.R. acknowledges financial support from the ANR project COROSHOCK ANR-17-CE31-0006-01 and from the ERC project SLOW_SOURCE \u2013 DLV-819189. \n\nData availability: All data used in this study is available to the public via NASA's Space Physics Data Facility (SPDF) at https://spdf.gsfc.nasa.gov/. \n\nAuthor Contributions: D.J.M. is IS\u2609IS Principal Investigator (PI) and led the data analysis and writing of the study. E.R.C. is IS\u2609IS Deputy PI, helped develop EPI-Hi, and participated in the data analysis. C.M.S.C. helped develop EPI-Hi and participated in the data analysis. A.C.C. helped develop EPI-Hi and participated in the data analysis. A.J.D. helped develop EPI-Hi and participated in the data analysis. M.I.D. participated in the data analysis. J.G. participated in the data analysis. M.E.H. helped develop EPI-Lo and participated in the data analysis. C.J.J. produced Figs. 3, 4 and participated in the data analysis. S.M.K. participated in the data analysis. A.W.L. helped develop EPI-Hi and participated in the data analysis. R.A.L. helped develop EPI-Hi and participated in the data analysis. O.M. participated in the data analysis. W.H.M. participated in the data analysis. R.L.M. led the development of EPI-Lo and participated in the data analysis. R.A.M. helped develop EPI-Hi and participated in the data analysis. D.G.M. helped develop EPI-Lo and participated in the data analysis. A.P. participated in the data analysis. J.S.R. helped develop EPI-Hi and participated in the data analysis. E.C.R. participated in the data analysis. N.A.S. led the development of the IS\u2609IS Science Operations Center and participated in the data analysis. E.C.S. helped develop EPI-Hi and participated in the data analysis. J.R.S. led the development of the analysis tool, produced Figs. 1, 2, and participated in the data analysis. M.E.W. led the development of EPI-Hi and participated in the data analysis. S.D.B. is FIELDS PI and participated in the data analysis. J.C.K. is SWEAP PI and participated in the data analysis. A.W.C. helped develop SWEAP and participated in the data analysis. K.E.K. helped develop SWEAP and participated in the data analysis. R.J.M. helped develop FIELDS and participated in the data analysis. M.P. helped develop FIELDS and participated in the data analysis. M.L.S. helped develop SWEAP and participated in the data analysis. A.P.R. led the CME simulation work and participated in the data analysis. \n\nThe authors declare no competing interests.\n\nAccepted Version - nihms-1539229.pdf
Supplemental Material - 41586_2019_1811_Fig5_ESM.jpg
Supplemental Material - 41586_2019_1811_Fig6_ESM.jpg
",
"abstract": "NASA's Parker Solar Probe mission recently plunged through the inner heliosphere of the Sun to its perihelia, about 24 million kilometres from the Sun. Previous studies farther from the Sun (performed mostly at a distance of 1 astronomical unit) indicate that solar energetic particles are accelerated from a few kiloelectronvolts up to near-relativistic energies via at least two processes: 'impulsive' events, which are usually associated with magnetic reconnection in solar flares and are typically enriched in electrons, helium-3 and heavier ions, and 'gradual' events, which are typically associated with large coronal-mass-ejection-driven shocks and compressions moving through the corona and inner solar wind and are the dominant source of protons with energies between 1 and 10 megaelectronvolts. However, some events show aspects of both processes and the electron\u2013proton ratio is not bimodally distributed, as would be expected if there were only two possible processes. These processes have been very difficult to resolve from prior observations, owing to the various transport effects that affect the energetic particle population en route to more distant spacecraft. Here we report observations of the near-Sun energetic particle radiation environment over the first two orbits of the probe. We find a variety of energetic particle events accelerated both locally and remotely including by corotating interaction regions, impulsive events driven by acceleration near the Sun, and an event related to a coronal mass ejection. We provide direct observations of the energetic particle radiation environment in the region just above the corona of the Sun and directly explore the physics of particle acceleration and transport.",
"date": "2019-12-12",
"date_type": "published",
"publication": "Nature",
"volume": "576",
"number": "7786",
"publisher": "Nature Publishing Group",
"pagerange": "223-227",
"id_number": "CaltechAUTHORS:20190827-123135234",
"issn": "0028-0836",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190827-123135234",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "Agence Nationale pour la Recherche (ANR)",
"grant_number": "ANR-17-CE31-0006-01"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "819189"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41586-019-1811-1",
"pmcid": "PMC6908744",
"primary_object": {
"basename": "41586_2019_1811_Fig5_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/0c97f-h2t19/files/41586_2019_1811_Fig5_ESM.jpg"
},
"related_objects": [
{
"basename": "41586_2019_1811_Fig6_ESM.jpg",
"url": "https://authors.library.caltech.edu/records/0c97f-h2t19/files/41586_2019_1811_Fig6_ESM.jpg"
},
{
"basename": "nihms-1539229.pdf",
"url": "https://authors.library.caltech.edu/records/0c97f-h2t19/files/nihms-1539229.pdf"
}
],
"pub_year": "2019",
"author_list": "McComas, D. J.; Cohen, C. M. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5gydx-ddp69",
"eprint_id": 100292,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:17:43",
"lastmod": "2026-03-31 14:46:38",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Relatores-N-C",
"name": {
"family": "Relatores",
"given": "Nicole C."
},
"orcid": "0000-0002-6041-6388"
},
{
"id": "Newman-A-B",
"name": {
"family": "Newman",
"given": "Andrew B."
},
"orcid": "0000-0001-7769-8660"
},
{
"id": "Simon-J-D",
"name": {
"family": "Simon",
"given": "Joshua D."
}
},
{
"id": "Ellis-R-S",
"name": {
"family": "Ellis",
"given": "Richard S."
},
"orcid": "0000-0001-7782-7071"
},
{
"id": "Truong-Phuongmai",
"name": {
"family": "Truong",
"given": "Phuongmai"
},
"orcid": "0000-0001-9248-6631"
},
{
"id": "Blitz-L",
"name": {
"family": "Blitz",
"given": "Leo"
},
"orcid": "0000-0002-4272-4432"
},
{
"id": "Bolatto-A-D",
"name": {
"family": "Bolatto",
"given": "Alberto"
},
"orcid": "0000-0002-5480-5686"
},
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "Christopher"
},
"orcid": "0000-0002-8650-1644"
},
{
"id": "Matuszewski-M",
"name": {
"family": "Matuszewski",
"given": "Matt"
}
},
{
"id": "Morrissey-P",
"name": {
"family": "Morrissey",
"given": "Patrick"
},
"orcid": "0000-0001-8177-1023"
},
{
"id": "Neill-J-D",
"name": {
"family": "Neill",
"given": "James D."
},
"orcid": "0000-0002-0466-1119"
}
]
},
"title": "The Dark Matter Distributions in Low-mass Disk Galaxies. II. The Inner Density Profiles",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galaxy structure; Galaxy kinematics; Dwarf galaxies; Dark matter",
"note": "\u00a9 2019. The American Astronomical Society. \n\nReceived 2019 June 19; revised 2019 October 28; accepted 2019 October 29; published 2019 December 13. \n\nWe would like to thank Alex Lazar and James Bullock for providing data used in Figure 11 in advance of publication, T. K. Chan for providing data used in Figure 11 and for helpful discussions, and Andrew Pontzen and J.A. Sellwood for their insightful comments. \n\nWe acknowledge the usage of the HyperLeda database (http://leda.univ-lyon1.fr). This research has made use of NASA's Astrophysics Data System.\n\nPublished - Relatores_2019_ApJ_887_94.pdf
Submitted - 1911.05836.pdf
",
"abstract": "Dark-matter-only simulations predict that dark matter halos have steep, cuspy inner density profiles, while observations of dwarf galaxies find a range of inner slopes that are often much shallower. There is debate whether this discrepancy can be explained by baryonic feedback or if it may require modified dark matter models. In Paper I of this series, we obtained high-resolution integral field H\u03b1 observations for 26 dwarf galaxies with M* = 10^(8.1)\u221210^(9.7) M_\u2299. We derived rotation curves from our observations, which we use here to construct mass models. We model the total mass distribution as the sum of a generalized Navarro\u2013Frenk\u2013White (NFW) dark matter halo and the stellar and gaseous components. Our analysis of the slope of the dark matter density profile focuses on the inner 300\u2013800 pc, chosen based on the resolution of our data and the region resolved by modern hydrodynamical simulations. The inner slope measured using ionized and molecular gas tracers is consistent, and it is additionally robust to the choice of stellar mass-to-light ratio. We find a range of dark matter profiles, including both cored and cuspy slopes, with an average of \u03c1}_(DM ~ r^(-0.74 \u00b1 0.07), shallower than the NFW profile, but steeper than those typically observed for lower-mass galaxies with M* ~ 10^(7.5) M_\u2299. Simulations that reproduce the observed slopes in those lower-mass galaxies also produce slopes that are too shallow for galaxies in our mass range. We therefore conclude that supernova feedback models do not yet provide a fully satisfactory explanation for the observed trend in dark matter slopes.",
"date": "2019-12-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "887",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 94",
"id_number": "CaltechAUTHORS:20191213-105055057",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191213-105055057",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab5305",
"primary_object": {
"basename": "1911.05836.pdf",
"url": "https://authors.library.caltech.edu/records/5gydx-ddp69/files/1911.05836.pdf"
},
"related_objects": [
{
"basename": "Relatores_2019_ApJ_887_94.pdf",
"url": "https://authors.library.caltech.edu/records/5gydx-ddp69/files/Relatores_2019_ApJ_887_94.pdf"
}
],
"pub_year": "2019",
"author_list": "Relatores, Nicole C.; Newman, Andrew B.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/s0bt8-xes74",
"eprint_id": 100153,
"eprint_status": "archive",
"datestamp": "2023-08-22 03:13:55",
"lastmod": "2026-03-31 05:18:44",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zhao-Lingling",
"name": {
"family": "Zhao",
"given": "L.-L."
},
"orcid": "0000-0002-4299-0490"
},
{
"id": "Zank-G-P",
"name": {
"family": "Zank",
"given": "G. P."
},
"orcid": "0000-0002-4642-6192"
},
{
"id": "Hu-Qiang",
"name": {
"family": "Hu",
"given": "Q."
},
"orcid": "0000-0002-7570-2301"
},
{
"id": "Chen-Yu",
"name": {
"family": "Chen",
"given": "Y."
},
"orcid": "0000-0002-0065-7622"
},
{
"id": "Adhikari-L",
"name": {
"family": "Adhikari",
"given": "L."
},
"orcid": "0000-0003-1549-5256"
},
{
"id": "leRoux-J-A",
"name": {
"family": "leRoux",
"given": "J. A."
},
"orcid": "0000-0001-9199-2890"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Burlaga-L-F",
"name": {
"family": "Burlaga",
"given": "L. F."
},
"orcid": "0000-0002-5569-1553"
}
]
},
"title": "ACR Proton Acceleration Associated with Reconnection Processes beyond the Heliospheric Termination Shock",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Interplanetary particle acceleration; Solar magnetic reconnection; Termination shock; Solar wind",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 August 26; revised 2019 October 10; accepted 2019 October 13; published 2019 December 2. \n\nWe acknowledge the partial support of the NSF EPSCoR RII-Track-1 Cooperative Agreement OIA-1655280, and partial support from an NSF/DOE Partnership in Basic Plasma Science and Engineering via NSF grant PHY-1707247, a NASA IBEX grant Sub0000167/80NSSC18K0237, NSF grant AGS 1650854 and NASA HGI-80NSSC19K0276, and a NASA grant NNX15AI65G. A.C. and E.S. are supported by NASA grant NNN12AA01C. L.F.B. acknowledges partial support from NASA/GSFC Contract 80GSFC19C0012.\n\nPublished - Zhao_2019_ApJ_886_144.pdf
",
"abstract": "One of the curious observations from the Voyagers is that the intensity of anomalous cosmic rays (ACRs) did not peak at the heliospheric termination shock (HTS) but instead a short distance (within ~1 au) downstream of the HTS. One possible explanation is that the interaction of the wavy heliospheric current sheet with the HTS enhances magnetic reconnection and generates numerous small-scale magnetic flux ropes in the heliosheath immediately downstream of the HTS. Charged particles are accelerated in this region due to Fermi acceleration and the reconnection electric field. In this work, we provide observational evidence of the presence of magnetic flux ropes in the heliosheath region just downstream of the HTS using a wavelet analysis of the reduced magnetic helicity and Grad\u2013Shafranov reconstruction techniques. The Zank et al. kinetic transport theory for particles propagating through the magnetic islands region is employed to fit the observed energetic proton intensities in the post-HTS region. Our modeling results agree reasonably well with the observations, which suggests that stochastic acceleration via reconnection processes can explain the ACR proton peak beyond the HTS.",
"date": "2019-12-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "886",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 144",
"id_number": "CaltechAUTHORS:20191202-155700225",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191202-155700225",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "OIA-1655280"
},
{
"agency": "NSF",
"grant_number": "PHY-1707247"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0237"
},
{
"agency": "NSF",
"grant_number": "AGS-1650854"
},
{
"agency": "NASA",
"grant_number": "80NSSC19K0276"
},
{
"agency": "NASA",
"grant_number": "NNX15AI65G"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
},
{
"agency": "NASA",
"grant_number": "80GSFC19C0012"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab4db4",
"primary_object": {
"basename": "Zhao_2019_ApJ_886_144.pdf",
"url": "https://authors.library.caltech.edu/records/s0bt8-xes74/files/Zhao_2019_ApJ_886_144.pdf"
},
"pub_year": "2019",
"author_list": "Zhao, L.-L.; Zank, G. P.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nszev-9rn54",
"eprint_id": 99763,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:59:13",
"lastmod": "2026-03-31 14:32:18",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mori-Kaya",
"name": {
"family": "Mori",
"given": "Kaya"
},
"orcid": "0000-0002-9709-5389"
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "Charles J."
}
},
{
"id": "Mandel-S",
"name": {
"family": "Mandel",
"given": "Shifra"
}
},
{
"id": "Schutt-Y-E",
"name": {
"family": "Schutt",
"given": "Yve E."
}
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Coerver-A",
"name": {
"family": "Coerver",
"given": "Anna"
}
},
{
"id": "Baganoff-F-K",
"name": {
"family": "Baganoff",
"given": "Frederick K."
}
},
{
"id": "Dykaar-H",
"name": {
"family": "Dykaar",
"given": "Hannah"
}
},
{
"id": "Grindlay-J-E",
"name": {
"family": "Grindlay",
"given": "Jonathan E."
},
"orcid": "0000-0002-1323-5314"
},
{
"id": "Haggard-D",
"name": {
"family": "Haggard",
"given": "Daryl"
},
"orcid": "0000-0001-6803-2138"
},
{
"id": "Heuer-K",
"name": {
"family": "Heuer",
"given": "Keri"
}
},
{
"id": "Hong-Jaesub",
"name": {
"family": "Hong",
"given": "Jaesub"
}
},
{
"id": "Hord-B-J",
"name": {
"family": "Hord",
"given": "Benjamin J."
}
},
{
"id": "Jin-Chichuan",
"name": {
"family": "Jin",
"given": "Chichuan"
},
"orcid": "0000-0002-2006-1615"
},
{
"id": "Nynka-M",
"name": {
"family": "Nynka",
"given": "Melania"
},
"orcid": "0000-0002-3310-1946"
},
{
"id": "Ponti-G",
"name": {
"family": "Ponti",
"given": "Gabriele"
},
"orcid": "0000-0003-0293-3608"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
}
]
},
"title": "NuSTAR and Chandra Observations of New X-Ray Transients in the Central Parsec of the Galaxy",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galactic center; X-ray transient sources; low-mass X-ray\nbinary stars; X-ray telescopes",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 August 14; revised 2019 October 3; accepted 2019 October 3; published 2019 November 11. \n\nThis work used data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. We made use of the NuSTAR Data Analysis Software (NuSTAR-DAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We acknowledge the scheduling, data processing, and archive teams from the Chandra X-ray Observatory Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration (NASA) under contract NAS8-03060. G.P. acknowledges financial contribution from the agreement ASI-INAF n.2017-14-H.0. C.J. acknowledges the National Natural Science Foundation of China through grant 11873054. D.H. acknowledges support from the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant and the Canadian Institute for Advanced Research (CIFAR) Azrieli Global Scholars program. We would like to thank Daniela Huppenkothen for insightful discussions on NuSTAR timing analysis and Stingray software. We acknowledge help from Ninad Nirgudkar and Gabriel Lewis Bridges for generating the Swift/XRT light curve plots. \n\nSoftware: NuSTARDAS (v.1.7.1), HEAsoft (v6.21; HEASARC 2014), Stingray (Huppenkothen et al. 2019), XSPEC (v12.10.1; Arnaud 1996), SAOImage DS9 (Joye & Mandel 2003).\n\nPublished - Mori_2019_ApJ_885_142.pdf
Accepted Version - 1910.03459.pdf
",
"abstract": "We report NuSTAR and Chandra observations of two X-ray transients, SWIFT J174540.7\u2212290015 (T15) and SWIFT J174540.2\u2212290037 (T37), which were discovered by the Neil Gehrels Swift Observatory in 2016 within r ~ 1 pc of Sgr A*. NuSTAR detected bright X-ray outbursts from T15 and T37, likely in the soft and hard states, with 3\u201379 keV luminosities of 8 \u00d7 10\u00b3\u2076 and 3 \u00d7 10\u00b3\u2077 erg s\u207b\u00b9, respectively. No X-ray outbursts have previously been detected from the two transients and our Chandra ACIS analysis puts an upper limit of L_X \u227e 2 \u00d7 10\u00b3\u00b9 erg s\u207b\u00b9 on their quiescent 2\u20138 keV luminosities. No pulsations, significant quasi-periodic oscillations, or type I X-ray bursts were detected in the NuSTAR data. While T15 exhibited no significant red noise, the T37 power density spectra are well characterized by three Lorentzian components. The declining variability of T37 above \u03bd ~ 10 Hz is typical of black hole (BH) transients in the hard state. NuSTAR spectra of both transients exhibit a thermal disk blackbody, X-ray reflection with broadened Fe atomic features, and a continuum component well described by Comptonization models. Their X-ray reflection spectra are most consistent with high BH spin (a* \u2273 0.9) and large disk density (n_e ~ 10\u00b2\u00b9 cm\u207b\u00b3). Based on the best-fit ionization parameters and disk densities, we found that X-ray reflection occurred near the inner-disk radius, which was derived from the relativistic broadening and thermal disk component. These X-ray characteristics suggest the outbursting BH-low-mass X-ray binary scenario for both transients and yield the first BH spin measurements from X-ray transients in the central 100 pc region.",
"date": "2019-11-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "885",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 142",
"id_number": "CaltechAUTHORS:20191111-074450523",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191111-074450523",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11873054"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "Canadian Institute for Advanced Research (CIFAR)"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab4b47",
"primary_object": {
"basename": "1910.03459.pdf",
"url": "https://authors.library.caltech.edu/records/nszev-9rn54/files/1910.03459.pdf"
},
"related_objects": [
{
"basename": "Mori_2019_ApJ_885_142.pdf",
"url": "https://authors.library.caltech.edu/records/nszev-9rn54/files/Mori_2019_ApJ_885_142.pdf"
}
],
"pub_year": "2019",
"author_list": "Mori, Kaya; Hailey, Charles J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/tgyhj-1tg34",
"eprint_id": 97736,
"eprint_status": "archive",
"datestamp": "2023-08-19 18:37:33",
"lastmod": "2026-03-31 06:05:19",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Sridhar-N",
"name": {
"family": "Sridhar",
"given": "Navin"
},
"orcid": "0000-0002-5519-9550"
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Connors-R-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Forster-K",
"name": {
"family": "Foster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
}
]
},
"title": "The 2017 Failed Outburst of GX 339-4: Relativistic X-ray Reflection near the Black Hole Revealed by NuSTAR and Swift Spectroscopy",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 atomic processes \u2013 black hole physics \u2013 line: formation \u2013 X-rays: individual (GX 339-4)",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 May 4; revised 2019 August 1; accepted 2019 August 2; published 2019 October 29. \n\nWe thank the anonymous referee for the careful revision of this paper. We also thank Erin Kara and Didier Barret for enlightening discussions on the implications of the dual-lamppost model. J.A.G. acknowledges support from NASA grant NNX17AJ65G and from the Alexander von Humboldt Foundation. R.M.T.C. has been supported by NASA ADAP grant 80NSSC177K0515. V.G. is supported through the Margarete von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. N.S. would like to acknowledge the support from DST-INSPIRE and Caltech SURF-2017 fellowships. This work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift. - \n\nSoftware: xspec (v12.10.0c; Arnaud 1996), xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), relxill (v1.2.0; Dauser et al. 2014; Garc\u00eda et al. 2014), nustradas (v1.6.0).\n\nPublished - Garc\u00eda_2019_ApJ_885_48.pdf
Submitted - 1908.00965.pdf
",
"abstract": "We report on the spectroscopic analysis of the black hole binary GX 339\u22124 during its recent 2017\u20132018 outburst, observed simultaneously by the Swift and NuSTAR observatories. Although during this particular outburst the source failed to make state transitions, and despite Sun constraints during the peak luminosity, we were able to trigger four different observations sampling the evolution of the source in the hard state. We show that even for the lowest-luminosity observations the NuSTAR spectra show clear signatures of X-ray reprocessing (reflection) in an accretion disk. Detailed analysis of the highest signal-to-noise spectra with our family of relativistic reflection models RELXILL indicates the presence of both broad and narrow reflection components. We find that a dual-lamppost model provides a superior fit when compared to the standard single lamppost plus distant neutral reflection. In the dual-lamppost model two sources at different heights are placed on the rotational axis of the black hole, suggesting that the narrow component of the Fe K emission is likely to originate in regions far away in the disk, but still significantly affected by its rotational motions. Regardless of the geometry assumed, we find that the inner edge of the accretion disk reaches a few gravitational radii in all our fits, consistent with previous determinations at similar luminosity levels. This confirms a very low degree of disk truncation for this source at luminosities above ~1% Eddington. Our estimates of R_(in) reinforce the suggested behavior for an inner disk that approaches the innermost regions as the luminosity increases in the hard state.",
"date": "2019-11-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "885",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 48",
"id_number": "CaltechAUTHORS:20190809-154849136",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190809-154849136",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX17AJ65G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "European Social Fund"
},
{
"agency": "Baden-W\u00fcrttemberg Ministry of Science, Research and the Arts"
},
{
"agency": "Caltech Summer Undergraduate Research Fellowship (SURF)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab384f",
"primary_object": {
"basename": "1908.00965.pdf",
"url": "https://authors.library.caltech.edu/records/tgyhj-1tg34/files/1908.00965.pdf"
},
"related_objects": [
{
"basename": "Garc\u00eda_2019_ApJ_885_48.pdf",
"url": "https://authors.library.caltech.edu/records/tgyhj-1tg34/files/Garc\u00eda_2019_ApJ_885_48.pdf"
}
],
"pub_year": "2019",
"author_list": "Garc\u00eda, Javier A.; Tomsick, John A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/85fpw-hjk26",
"eprint_id": 98892,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:51:37",
"lastmod": "2026-03-31 05:47:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Edward C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "Alan C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "Bryant C."
}
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "Nand"
}
}
]
},
"title": "Cosmic ray measurements from Voyager 2 as it crossed into interstellar space",
"ispublished": "pub",
"full_text_status": "restricted",
"keywords": "Astronomy and planetary science; Space physics",
"note": "\u00a9 2019 Springer Nature Limited. \n\nReceived 21 July 2019; Accepted 27 September 2019; Published 04 November 2019. \n\nData availability: Most of the CRS data can be obtained by clicking on the DATA link at https://voyager.gsfc.nasa.gov/ and following other links to obtain rate and flux data. All data that were used in the figures can be provided by the corresponding author on request. \n\nWe thank L. Burlaga for providing magnetic field data before publication. A.C.C. acknowledges support from the International Space Sciences Institute in Bern, Switzerland, to participate in the international team The Physics of the Very Local Interstellar Medium in the autumn of 2018. This work was supported by NASA under grant NNN12AA01C. \n\nAuthor Contributions: All authors contributed to the production of this manuscript. A.C.C. and E.C.S. wrote the text. A.C.C., B.C.H. and N.L. performed the data analysis and A.C.C. and B.C.H. prepared the figures. All authors participated in reviewing and commenting on the paper and on the editor's and referees' comments. \n\nThe authors declare no competing interests.",
"abstract": "The interaction of the interstellar and solar winds is complex, as revealed by differences in intensities and anisotropies of low-energy ions (>0.5\u2009MeV per nucleon) originating inside the heliosphere and those of higher-energy Galactic cosmic rays (>70\u2009MeV per nucleon) originating outside, in the Milky Way. On 5 November 2018, Voyager 2 observed a sharp decrease in the intensity of low-energy ions and a simultaneous increase in the intensity of cosmic rays, indicating that Voyager 2 had crossed the heliopause at 119\u2009au and entered interstellar space about six years after Voyager 1. Unlike Voyager 1, which found that two interstellar flux tubes had invaded the heliosheath and served as precursors to the heliopause, Voyager 2 found no similar precursors. However, just beyond the heliopause Voyager 2 discovered a boundary layer, in which low-energy particles streamed outward along the magnetic field and cosmic ray intensities were only 90% of those further out.",
"date": "2019-11",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "3",
"number": "11",
"publisher": "Nature Publishing Group",
"pagerange": "1013-1018",
"id_number": "CaltechAUTHORS:20190926-164717298",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190926-164717298",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41550-019-0928-3",
"pub_year": "2019",
"author_list": "Stone, Edward C.; Cummings, Alan C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/m6355-zdn43",
"eprint_id": 98683,
"eprint_status": "archive",
"datestamp": "2023-08-19 18:28:35",
"lastmod": "2026-03-31 00:16:42",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Buisson-D-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
}
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Shaw-A-W",
"name": {
"family": "Shaw",
"given": "A. W."
}
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "J. A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "MAXI J1820+070 with NuSTAR I. An increase in variability frequency but a stable reflection spectrum: coronal properties and implications for the inner disc in black hole binaries",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs - black hole physics - X-rays: binaries",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 September 20. Received 2019 September 19; in original form 2019 May 31. Published: 27 September 2019. \n\nWe thank Fiona Harrison for approval of these DDT observations and Karl Forster for their prompt scheduling. DJKB acknowledges financial support from the Science and Technology Facilities Council (STFC). ACF acknowledges support from the ERC Advanced Grant FEEDBACK 340442. AWS is supported by an NSERC Discovery Grant and a Discovery Accelerator Supplement. This work has used data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has used the NuSTARDAS jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - stz2681.pdf
Submitted - 1909.04688.pdf
",
"abstract": "MAXI J1820+070 (optical counterpart ASASSN-18ey) is a black hole candidate discovered through its recent very bright outburst. The low extinction column and long duration at high flux allow detailed measurements of the accretion process to be made. In this work, we compare the evolution of X-ray spectral and timing properties through the initial hard state of the outburst. We show that the inner accretion disc, as measured by relativistic reflection, remains steady throughout this period of the outburst. Nevertheless, subtle spectral variability is observed, which is well explained by a change in coronal geometry. However, characteristic features of the temporal variability \u2013 low-frequency roll-over and quasi-periodic oscillation frequency \u2013 increase drastically in frequency, as the outburst proceeds. This suggests that the variability time-scales are governed by coronal conditions rather than solely by the inner disc radius. We also find a strong correlation between X-ray luminosity and coronal temperature. This can be explained by electron pair production with a changing effective radius and a non-thermal electron fraction of \u223c20 per\u2009cent.",
"date": "2019-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "490",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "1350-1362",
"id_number": "CaltechAUTHORS:20190917-134739032",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-134739032",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stz2681",
"primary_object": {
"basename": "1909.04688.pdf",
"url": "https://authors.library.caltech.edu/records/m6355-zdn43/files/1909.04688.pdf"
},
"related_objects": [
{
"basename": "stz2681.pdf",
"url": "https://authors.library.caltech.edu/records/m6355-zdn43/files/stz2681.pdf"
}
],
"pub_year": "2019",
"author_list": "Buisson, D. J. K.; Fabian, A. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/qh946-0h079",
"eprint_id": 98668,
"eprint_status": "archive",
"datestamp": "2023-08-19 18:28:22",
"lastmod": "2026-03-31 05:57:55",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Longinotti-A-L",
"name": {
"family": "Longinotti",
"given": "A. L."
}
},
{
"id": "Schartel-N",
"name": {
"family": "Schartel",
"given": "N."
}
},
{
"id": "Grupe-D",
"name": {
"family": "Grupe",
"given": "D."
},
"orcid": "0000-0002-9961-3661"
},
{
"id": "Komossa-S",
"name": {
"family": "Komossa",
"given": "S."
}
},
{
"id": "Kriss-G-A",
"name": {
"family": "Kriss",
"given": "G."
}
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Gallo-L-C",
"name": {
"family": "Gallo",
"given": "L."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Jiang-J",
"name": {
"family": "Jiang",
"given": "J."
}
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Krongold-Y",
"name": {
"family": "Krongold",
"given": "Y."
}
},
{
"id": "Matzeu-G-A",
"name": {
"family": "Matzeu",
"given": "G. A."
}
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Santos-Lle\u00f3-M",
"name": {
"family": "Santos-Lle\u00f3",
"given": "M."
}
}
]
},
"title": "The nuclear environment of the NLS1 Mrk 335: obscuration of the X-ray line emission by a variable outflow",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013 black hole physics \u2013 galaxies: active \u2013 X-rays: individual:\nMrk 335",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 September 10. Received 2019 September 6; in original form 2019 July 30. Published: 13 September 2019. \n\nMLP, GAM, and CP are supported by European Space Agency (ESA) Research Fellowships. ACF acknowledges support from ERC Advanced Grant 340442. ALL is supported by CONACyT grant CB-2016-01-286316. JJ acknowledges support from the Cambridge Trust and the Chinese Scholarship Council joint scholarship (201604100032). DG acknowledges support by HST grant HST-GO-15439.002-A. Based on observations obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We acknowledge support from the Faculty of the European Space Astronomy Centre (ESAC). We thank the anonymous referee for their constructive feedback, which has significantly improved this work.\n\nPublished - stz2566.pdf
Submitted - 1909.04924.pdf
",
"abstract": "We present XMM\u2013Newton, NuSTAR, Swift, and Hubble Space Telescope observations of the Narrow-line Seyfert 1 galaxy Mrk 335 in a protracted low state in 2018 and 2019. The X-ray flux is at the lowest level so far observed, and the extremely low continuum flux reveals a host of soft X-ray emission lines from photoionized gas. The simultaneous UV flux drop suggests that the variability is intrinsic to the source, and we confirm this with broad-band X-ray spectroscopy. The dominance of the soft X-ray lines at low energies and distant reflection at high energies, is therefore due to the respective emission regions being located far enough from the X-ray source that they have not yet seen the flux drop. Between the two XMM\u2013Newton spectra, taken 6 months apart, the emission line ratio in the O\u2009VII triplet changes drastically. We attribute this change to a drop in the ionization of intervening warm absorption, which means that the absorber must cover a large fraction of the line emitting region, and extend much further from the black hole than previously assumed. The HST spectrum, taken in 2018, shows that new absorption features have appeared on the blue wings of C\u2009III*, Ly\u2009\u03b1, N\u2009V, Si\u2009IV, and C\u2009IV, likely due to absorbing gas cooling in response to the low flux state.",
"date": "2019-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "490",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "683-697",
"id_number": "CaltechAUTHORS:20190916-161112944",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190916-161112944",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "CB-2016-01-286316"
},
{
"agency": "Cambridge Trust"
},
{
"agency": "Chinese Scholarship Council",
"grant_number": "201604100032"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-GO-15439.002-A"
},
{
"agency": "ESA Member States"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Space Astronomy Centre"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stz2566",
"primary_object": {
"basename": "1909.04924.pdf",
"url": "https://authors.library.caltech.edu/records/qh946-0h079/files/1909.04924.pdf"
},
"related_objects": [
{
"basename": "stz2566.pdf",
"url": "https://authors.library.caltech.edu/records/qh946-0h079/files/stz2566.pdf"
}
],
"pub_year": "2019",
"author_list": "Parker, M. L.; Longinotti, A. L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xrmrx-xzk59",
"eprint_id": 98673,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:44:22",
"lastmod": "2026-03-31 15:57:54",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Gorgone-N-M",
"name": {
"family": "Gorgone",
"given": "Nicholas M."
}
},
{
"name": {
"family": "Kouveliotou",
"given": "Chryssa"
}
},
{
"name": {
"family": "Negoro",
"given": "Hitoshi"
}
},
{
"name": {
"family": "Wijers",
"given": "Ralph A. M. J."
}
},
{
"name": {
"family": "Bozzo",
"given": "Enrico"
}
},
{
"name": {
"family": "Guiriec",
"given": "Sylvain"
}
},
{
"name": {
"family": "Bult",
"given": "Peter"
}
},
{
"name": {
"family": "Huppenkothen",
"given": "Daniela"
}
},
{
"name": {
"family": "G\u00f6\u011f\u00fcs",
"given": "Ersin"
}
},
{
"name": {
"family": "Bahramian",
"given": "Arash"
}
},
{
"name": {
"family": "Kennea",
"given": "Jamie"
}
},
{
"name": {
"family": "Linford",
"given": "Justin D."
}
},
{
"name": {
"family": "Miller-Jones",
"given": "James"
}
},
{
"name": {
"family": "Baring",
"given": "Matthew G."
}
},
{
"name": {
"family": "Beniamini",
"given": "Paz"
}
},
{
"name": {
"family": "Chakrabarty",
"given": "Deepto"
}
},
{
"name": {
"family": "Granot",
"given": "Jonathan"
}
},
{
"name": {
"family": "Hailey",
"given": "Charles"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"name": {
"family": "Hartmann",
"given": "Dieter H."
}
},
{
"name": {
"family": "Iwakiri",
"given": "Wataru"
}
},
{
"name": {
"family": "Kaper",
"given": "Lex"
}
},
{
"name": {
"family": "Kara",
"given": "Erin"
}
},
{
"name": {
"family": "Mazzola",
"given": "Simona"
}
},
{
"name": {
"family": "Murata",
"given": "Katsuhiro"
}
},
{
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"name": {
"family": "Tomsick",
"given": "John A."
}
},
{
"name": {
"family": "van der Horst",
"given": "Alexander J."
},
"orcid": "0000-0001-9149-6707"
},
{
"name": {
"family": "Younes",
"given": "George A."
}
}
]
},
"title": "Discovery and Identification of MAXI J1621-501 as a Type I X-ray Burster with a Super-Orbital Period",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Low-mass X-ray binary stars; X-ray transient sources; X-ray bursters",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 June 27; revised 2019 August 15; accepted 2019 August 21; published 2019 October 22. \n\nWe thank the anonymous referee, whose comments improved the quality of this work. N.G., C.K., and P.B. acknowledge support from Chandra award number GO8-19061X and Swift award number NNH16ZDA001N-SWIFT. The IRSF project is supported by the Grants-in-Aid for Scientific Research on Priority Areas (A) (No. 10147207 and No. 10147214). H.N. acknowledges support from a Grant-in-Aid for Scientific Research (No. 16K05301). The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. Special thanks go to Nobuyuki Kawai, Christina Gilligan, and Jill Neeley for their indispensable roles in data acquisition for this project. D.H. acknowledges support from the DIRAC Institute in the Department of Astronomy at the University of Washington. The DIRAC Institute is supported through generous gifts from the Charles and Lisa Simonyi Fund for Arts and Sciences, and the Washington Research Foundation. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We thank all operations, software and calibration teams contributing to the facilities used in this study for support with the execution and analysis of these observations. \n\nFacilities: Swift - Swift Gamma-Ray Burst Mission, Chandra - , NuSTAR - , NICER - , MAXI - , INTEGRAL - , ATCA - , IRSF - , Gemini - , ADS - , HEASARC. - \n\nSoftware: MIRIAD (Sault et al. 1995), Stingray (Huppenkothen et al. 2016, 2019), emcee (Foreman-Mackey et al. 2013), CIAO (v4.9.3; Fruscione et al. 2006), HEAsoft (v624; HEASARC 2014), XSPEC (v12.10.0; Arnaud 1996).\n\nPublished - Gorgone_2019_ApJ_884_168.pdf
Submitted - 1908.03590.pdf
",
"abstract": "MAXI J1621-501 is the first Swift/XRT Deep Galactic Plane Survey transient that was followed up with a multitude of space missions (NuSTAR, Swift, Chandra, NICER, INTEGRAL, and MAXI) and ground-based observatories (Gemini, IRSF, and ATCA). The source was discovered with MAXI on 2017 October 19 as a new, unidentified transient. Further observations with NuSTAR revealed 2 Type I X-ray bursts, identifying MAXI J1621-501 as a Low Mass X-ray Binary (LMXB) with a neutron star primary. Overall, 24 Type I bursts were detected from the source during a 15 month period. At energies below 10 keV, the source spectrum was best fit with three components: an absorbed blackbody with kT = 2.3 keV, a cutoff power law with index \u0393 = 0.7, and an emission line centered on 6.3 keV. Timing analysis of the X-ray persistent emission and burst data has not revealed coherent pulsations from the source or an orbital period. We identified, however, a super-orbital period \u223c78 days in the source X-ray light curve. This period agrees very well with the theoretically predicted radiative precession period of \u223c82 days. Thus, MAXI J1621-501 joins a small group of sources characterized with super-orbital periods.",
"date": "2019-10-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "884",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 168",
"id_number": "CaltechAUTHORS:20190917-100259555",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-100259555",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "GO8-19061X"
},
{
"agency": "NASA",
"grant_number": "NNH16ZDA001N-SWIFT"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "10147207"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "10147214"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)",
"grant_number": "16K05301"
},
{
"agency": "Australian Government"
},
{
"agency": "Charles and Lisa Simonyi Fund for Arts and Sciences"
},
{
"agency": "Washington Research Foundation"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab3e43",
"primary_object": {
"basename": "1908.03590.pdf",
"url": "https://authors.library.caltech.edu/records/xrmrx-xzk59/files/1908.03590.pdf"
},
"related_objects": [
{
"basename": "Gorgone_2019_ApJ_884_168.pdf",
"url": "https://authors.library.caltech.edu/records/xrmrx-xzk59/files/Gorgone_2019_ApJ_884_168.pdf"
}
],
"pub_year": "2019",
"author_list": "Gorgone, Nicholas M.; Kouveliotou, Chryssa; et al."
},
{
"id": "https://authors.library.caltech.edu/records/be9za-1y628",
"eprint_id": 98670,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:39:20",
"lastmod": "2026-03-31 00:10:25",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Lau-Ryan-M",
"name": {
"family": "Lau",
"given": "R. M."
}
},
{
"id": "Davies-B",
"name": {
"family": "Davies",
"given": "B."
}
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Kennea-J-A",
"name": {
"family": "Kennea",
"given": "J. A."
},
"orcid": "0000-0002-6745-4790"
},
{
"id": "Tramper-F",
"name": {
"family": "Tramper",
"given": "F."
}
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Discovery of a red supergiant donor star in SN2010da/NGC 300 ULX-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "High-mass X-ray binary stars, Late-type supergiant stars; Neutron stars",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 August 1; revised 2019 August 27; accepted 2019 September 4; published 2019 September 25. \n\nM.H. would like to thank M. Bachetti, E. Levesque, G. Vasilopoulos, I. el Mellah, S. Guillot, and E. Quatart for useful discussions. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme(s) 102.D-0535(A). \n\nFacility: VLT(X-shooter). - \n\nSoftware: Astropy (Astropy Collaboration et al. 2013), Reflex (Freudling et al. 2013), Molecfit (Kausch et al. 2015; Smette et al. 2015), TURBOSPECTRUM (Plez 2012).\n\nPublished - Heida_2019_ApJL_883_L34.pdf
Submitted - 1909.02171.pdf
",
"abstract": "SN2010da/NGC 300 ULX-1 was first detected as a supernova impostor in 2010 May and was recently discovered to be a pulsating ultraluminous X-ray source. In this Letter, we present Very Large Telescope/X-shooter spectra of this source obtained in 2018 October, covering the wavelength range 350\u20132300 nm. The J- and H-bands clearly show the presence of a red supergiant (RSG) donor star that is best matched by a MARCS stellar atmosphere with T_(eff) = 3650\u20133900 K and log(L_(bol)/L\u2299) = 4.25 \u00b1 0.10, which yields a stellar radius R = 310 \u00b1 70R \u2299. To fit the full spectrum, two additional components are required: a blue excess that can be fitted either by a hot blackbody (T \u2273 20,000 K) or a power law (spectral index \u03b1 \u2248 4) and is likely due to X-ray emission reprocessed in the outer accretion disk or the donor star; and a red excess that is well fitted by a blackbody with a temperature of ~1100 K, and is likely due to warm dust in the vicinity of SN2010da. The presence of an RSG in this system implies an orbital period of at least 0.8\u20132.1 yr, assuming Roche-lobe overflow. Given the large donor-to-compact object mass ratio, orbital modulations of the radial velocity of the RSG are likely undetectable. However, the radial velocity amplitude of the neutron star is large enough (up to 40\u201360 km s^(\u22121)) to potentially be measured in the future, unless the system is viewed at a very unfavorable inclination.",
"date": "2019-10-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "883",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L34",
"id_number": "CaltechAUTHORS:20190917-093523828",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-093523828",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/2041-8213/ab4139",
"primary_object": {
"basename": "1909.02171.pdf",
"url": "https://authors.library.caltech.edu/records/be9za-1y628/files/1909.02171.pdf"
},
"related_objects": [
{
"basename": "Heida_2019_ApJL_883_L34.pdf",
"url": "https://authors.library.caltech.edu/records/be9za-1y628/files/Heida_2019_ApJL_883_L34.pdf"
}
],
"pub_year": "2019",
"author_list": "Heida, M.; Lau, R. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5b81k-dg856",
"eprint_id": 97799,
"eprint_status": "archive",
"datestamp": "2023-08-19 18:03:37",
"lastmod": "2026-03-31 15:46:38",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "L\u00f3pez-K-M",
"name": {
"family": "L\u00f3pez",
"given": "K. M."
}
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Roberts-T-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Moon-Dae-Sik",
"name": {
"family": "Moon",
"given": "D.-S."
},
"orcid": "0000-0003-4200-5064"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Discovery and analysis of a ULX nebula in NGC 3521",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "regions \u2013 infrared: stars \u2013 X-rays: binaries \u2013 X-rays: individual: [SST2011] J110545.62 + 000016.2",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 July 29. Received 2019 July 17; in original form 2019 June 4. Published: 05 August 2019. \n\nBased on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme 0100.D-0660(B).\n\nWe would like to thank the anonymous referee whose valuable comments helped improve the quality of this work. KML would like to thank Davide Lena for valuable discussions. PGJ and KML acknowledge funding from the European Research Council under ERC Consolidator Grant agreement no. 647208. TPR acknowledges funding from the Science and Technology Facilities Council (STFC) as part of the consolidated grant ST/L00075X/1. MAPT acknowledges support via a Ram\u00f3n y Cajal Fellowship (RYC-2015-17854). MAPT also acknowledges support by the Spanish Ministry of Economy, Industry and Competitiveness under grant AYA2017-83216-P. DJW acknowledges support from an STFC Ernest Rutherford Fellowship. We have made use of the SIMBAD data base, operated at CDS, Strasbourg, France; of the NASA/IPAC Extragalactic Data base (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration; and of data obtained from the Chandra Data Archive and the Chandra Source Catalogue, and software provided by the Chandra X-ray Center (CXC) in the application packages CIAO, ChIPS, and Sherpa.\n\nPublished - stz2127.pdf
Submitted - 1907.12814.pdf
",
"abstract": "We present Very Large Telescope/X-shooter and Chandra X-ray observatory/ACIS observations of the ULX [SST2011] J110545.62 + 000016.2 in the galaxy NGC 3521. The source identified as a candidate near-infrared counterpart to the ULX in our previous study shows an emission line spectrum of numerous recombination and forbidden lines in the visible and near-infrared spectral regime. The emission from the candidate counterpart is spatially extended (\u223c34\u2009pc) and appears to be connected with an adjacent H\u2009II region, located \u223c138\u2009pc to the NE. The measured velocities of the emission lines confirm that both the candidate counterpart and H\u2009II region reside in NGC 3521. The intensity ratios of the emission lines from the ULX counterpart show that the line emission originates from the combined effect of shock and photoionization of low metallicity (12 + log\u2009 (O/H) = 8.19 \u00b1 0.11) gas. Unfortunately, there is no identifiable spectral signature directly related to the photosphere of the mass-donor star in our spectrum. From the archival Chandra data, we derive the X-ray luminosity of the source in the 0.3\u20137\u2009keV range to be (1.9 \u00b1 0.8) \u00d7 10\u2074\u2070\u2009er\u2009g\u2009cm\u207b\u00b2\u2009s\u207b\u00b9, almost a factor of four higher than what is previously reported.",
"date": "2019-10",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "489",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "1249-1264",
"id_number": "CaltechAUTHORS:20190812-150823615",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190812-150823615",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/L00075X/1"
},
{
"agency": "Ram\u00f3n y Cajal Fellowship",
"grant_number": "RYC-2015-17854"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2017-83216-P"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stz2127",
"primary_object": {
"basename": "1907.12814.pdf",
"url": "https://authors.library.caltech.edu/records/5b81k-dg856/files/1907.12814.pdf"
},
"related_objects": [
{
"basename": "stz2127.pdf",
"url": "https://authors.library.caltech.edu/records/5b81k-dg856/files/stz2127.pdf"
}
],
"pub_year": "2019",
"author_list": "L\u00f3pez, K. M.; Jonker, P. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mb9vm-7x667",
"eprint_id": 96476,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:55:47",
"lastmod": "2026-03-31 14:41:50",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Trakhtenbrot-B",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Arcavi-I",
"name": {
"family": "Arcavi",
"given": "Iair"
},
"orcid": "0000-0001-7090-4898"
},
{
"id": "MacLeod-C-L",
"name": {
"family": "MacLeod",
"given": "Chelsea L."
}
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Graham-M-L",
"name": {
"family": "Graham",
"given": "Melissa L."
},
"orcid": "0000-0002-9154-3136"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Burke-J",
"name": {
"family": "Burke",
"given": "Jamison"
}
},
{
"id": "Hiramatsu-Daichi",
"name": {
"family": "Hiramatsu",
"given": "Daichi"
}
},
{
"id": "Hosseinzadeh-G",
"name": {
"family": "Hosseinzadeh",
"given": "Griffin"
},
"orcid": "0000-0002-0832-2974"
},
{
"id": "Howell-D-A",
"name": {
"family": "Howell",
"given": "D. Andrew"
},
"orcid": "0000-0003-4253-656X"
},
{
"id": "Smartt-S-J",
"name": {
"family": "Smartt",
"given": "Stephen J."
},
"orcid": "0000-0002-8229-1731"
},
{
"id": "Rest-A",
"name": {
"family": "Rest",
"given": "Armin"
}
},
{
"id": "Prieto-J-L-ASTRO",
"name": {
"family": "Prieto",
"given": "Jos\u00e9 L."
},
"orcid": "0000-0003-1072-2712"
},
{
"id": "Shappee-B-J",
"name": {
"family": "Shappee",
"given": "Benjamin J."
},
"orcid": "0000-0003-4631-1149"
},
{
"id": "Holoien-T-W-S",
"name": {
"family": "Holoien",
"given": "Thomas W.-S."
},
"orcid": "0000-0001-9206-3460"
},
{
"id": "Bersier-D",
"name": {
"family": "Bersier",
"given": "David"
}
},
{
"id": "Filippenko-A-V",
"name": {
"family": "Filippenko",
"given": "Alexei V."
},
"orcid": "0000-0003-3460-0103"
},
{
"id": "Brink-T-G",
"name": {
"family": "Brink",
"given": "Thomas G."
}
},
{
"id": "Zheng-Weikang",
"name": {
"family": "Zheng",
"given": "WeiKang"
},
"orcid": "0000-0002-2636-6508"
},
{
"id": "Li-Ruancun",
"name": {
"family": "Li",
"given": "Ruancun"
}
},
{
"id": "Remillard-R-A",
"name": {
"family": "Remillard",
"given": "Ronald A."
},
"orcid": "0000-0003-4815-0481"
},
{
"id": "Loewenstein-M",
"name": {
"family": "Loewenstein",
"given": "Michael"
}
}
]
},
"title": "1ES 1927+654: an AGN Caught Changing Look on a Timescale of Months",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: individual (1ES 1927+654) \u2013 galaxies: nuclei \u2013 quasars: emission lines \u2013 quasars: general",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 March 25; revised 2019 June 25; accepted 2019 July 13; published 2019 September 24. \n\nWe are grateful to the anonymous referee for helping us improve this manuscript. We thank Gwen Eadie, Bryce Bolin, and Dino Bekte\u0161evi\u0107 at UW for assistance with obtaining the APO spectra. We also thank Hagai Netzer, Dalya Baron, and Robert Antonucci for their insightful and constructive comments. R.L. was supported by the National Key R&D Program of China (2016YFA0400702) and the National Science Foundation of China (11721303). I.A. acknowledges support from the Israel Science Foundation (grant No. 2108/18). Support for J.L.P. is provided in part by FONDECYT through the grant 1191038 and by the Ministry of Economy, Development, and Tourisms Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. Support for A.V.F.'s research group has been provided by the TABASGO Foundation, the Christopher R. Redlich Fund, and the Miller Institute for Basic Research in Science (U.C. Berkeley). \n\nThis work made use of the MATLAB package for astronomy and astrophysics (Ofek 2014) and Astropy,30 a community-developed core Python package for Astronomy (The Astropy Collaboration et al. 2013, 2018). This research also made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. \n\nThis work made use of data from Las Cumbres Observatory; the All Sky Automated Survey for Supernovae (ASAS-SN); the Asteroid Terrestrial-impact Last Alert System (ATLAS) project; the Liverpool Telescope; the Lick Observatory; and the W. M. Keck Observatory. \n\nATLAS is primarily funded to search for near earth asteroids (NEOs) through NASA grants NN12AR55G, 80NSSC18K0284, and 80NSSC18K1575; byproducts of the NEO search include images and catalogs from the survey area. The ATLAS science products have been made possible through the contributions of the University of Hawaii Institute for Astronomy, the Queen's University Belfast, the Space Telescope Science Institute, and the South African Astronomical Observatory. ASAS-SN is supported by the Gordon and Betty Moore Foundation through grant GBMF5490 to the Ohio State University and NSF grant AST-1515927. Development of ASAS-SN has been supported by NSF grant AST-0908816, the Mt. Cuba Astronomical Foundation, the Center for Cosmology and AstroParticle Physics at the Ohio State University (CCAPP), the Chinese Academy of Sciences South America Center for Astronomy (CASSACA), the Villum Foundation, and George Skestos. We thank the Las Cumbres Observatory and its staff for its continuing support of the ASAS-SN project. The Liverpool Telescope is operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, with financial support from the UK Science and Technology Facilities Council. Research at Lick Observatory is partially supported by a generous gift from Google. The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA; the observatory was made possible by the generous financial support of the W. M. Keck Foundation. \n\nWe finally thank NASA HEASARC for making the Swift and NICER data available, and ESA for providing the XMM-Newton data. \n\nFacilities: HST (STIS) - , HST (COS) - , Swift (XRT and UVOT) - , NICER - , XMM - , ATLAS - , ASAS-SN - , MDM Observatory (OSMOS) - , Liverpool Telescope (SPRAT) - , Lick Observatory (Shane/Kast) - , Las Cumbres Observatory (FLOYDS) - , Keck (LRIS). -\n\nSoftware: astropy (The Astropy Collaboration et al. 2013, 2018), SExtractor (Bertin & Arnouts 1996), MAAT (Ofek 2014).\n\nPublished - Trakhtenbrot_2019_ApJ_883_94.pdf
Submitted - 1903.11084.pdf
",
"abstract": "We study the sudden optical and ultraviolet (UV) brightening of 1ES 1927+654, which until now was known as a narrow-line active galactic nucleus (AGN). 1ES 1927+654 was part of the small and peculiar class of \"true Type-2\" AGNs that lack broad emission lines and line-of-sight obscuration. Our high-cadence spectroscopic monitoring captures the appearance of a blue, featureless continuum, followed several weeks later by the appearance of broad Balmer emission lines. This timescale is generally consistent with the expected light travel time between the central engine and the broadline emission region in (persistent) broadline AGN. Hubble Space Telescope spectroscopy reveals no evidence for broad UV emission lines (e.g., C iv \u03bb1549, C iii] \u03bb1909, Mg ii \u03bb2798), probably owing to dust in the broadline emission region. To the best of our knowledge, this is the first case where the lag between the change in continuum and in broadline emission of a \"changing look\" AGN has been temporally resolved. The nature and timescales of the photometric and spectral evolution disfavor both a change in line-of-sight obscuration and a change of the overall rate of gas inflow as driving the drastic spectral transformations seen in this AGN. Although the peak luminosity and timescales are consistent with those of tidal disruption events seen in inactive galaxies, the spectral properties are not. The X-ray emission displays a markedly different behavior, with frequent flares on timescales of hours to days, and will be presented in a companion publication.",
"date": "2019-09-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "883",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 94",
"id_number": "CaltechAUTHORS:20190617-135726690",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190617-135726690",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Key Research and Development Program of China",
"grant_number": "2016YFA0400702"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11721303"
},
{
"agency": "Israel Science Foundation",
"grant_number": "2108/18"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1191038"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "TABASGO Foundation"
},
{
"agency": "Christopher R. Redlich Fund"
},
{
"agency": "Miller Institute for Basic Research in Science"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NN12AR55G"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0284"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K1575"
},
{
"agency": "Gordon and Betty Moore Foundation",
"grant_number": "GBMF5490"
},
{
"agency": "NSF",
"grant_number": "AST-1515927"
},
{
"agency": "NSF",
"grant_number": "AST-0908816"
},
{
"agency": "Mt. Cuba Astronomical Foundation"
},
{
"agency": "Ohio State University"
},
{
"agency": "Chinese Academy of Sciences South America Center for Astronomy (CASSACA)"
},
{
"agency": "Villum Foundation"
},
{
"agency": "George Skestos"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Google"
},
{
"agency": "W. M. Keck Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab39e4",
"primary_object": {
"basename": "1903.11084.pdf",
"url": "https://authors.library.caltech.edu/records/mb9vm-7x667/files/1903.11084.pdf"
},
"related_objects": [
{
"basename": "Trakhtenbrot_2019_ApJ_883_94.pdf",
"url": "https://authors.library.caltech.edu/records/mb9vm-7x667/files/Trakhtenbrot_2019_ApJ_883_94.pdf"
}
],
"pub_year": "2019",
"author_list": "Trakhtenbrot, Benny; Arcavi, Iair; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9b3bb-dny67",
"eprint_id": 98739,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:56:10",
"lastmod": "2026-03-31 00:02:14",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-R-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Shishkovsky-L",
"name": {
"family": "Shishkovsky",
"given": "L."
}
},
{
"id": "Bult-P-M",
"name": {
"family": "Bult",
"given": "P. M."
}
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Zoghbi-A",
"name": {
"family": "Zoghbi",
"given": "A."
},
"orcid": "0000-0002-0572-9613"
},
{
"id": "Strohmayer-T-E",
"name": {
"family": "Strohmayer",
"given": "T. E."
},
"orcid": "0000-0001-7681-5845"
},
{
"id": "Reynolds-M-T",
"name": {
"family": "Reynolds",
"given": "M."
}
},
{
"id": "Natalucci-L",
"name": {
"family": "Natalucci",
"given": "L."
},
"orcid": "0000-0002-6601-9543"
},
{
"id": "Miller-Jones-J-C-A",
"name": {
"family": "Miller-Jones",
"given": "J. C. A."
},
"orcid": "0000-0003-3124-2814"
},
{
"id": "Jaisawal-G-K",
"name": {
"family": "Jaisawal",
"given": "G. K."
},
"orcid": "0000-0002-6789-2723"
},
{
"id": "Guillot-S",
"name": {
"family": "Guillot",
"given": "S."
},
"orcid": "0000-0002-6449-106X"
},
{
"id": "Gendreau-K-C",
"name": {
"family": "Gendreau",
"given": "K. C."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Fiocchi-M",
"name": {
"family": "Fiocchi",
"given": "M."
},
"orcid": "0000-0001-5697-6019"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Chakrabarty-D",
"name": {
"family": "Chakrabarty",
"given": "D."
},
"orcid": "0000-0001-8804-8946"
},
{
"id": "Cackett-E-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Bahramian-A",
"name": {
"family": "Bahramian",
"given": "A."
},
"orcid": "0000-0003-2506-6041"
},
{
"id": "Arzoumanian-Z",
"name": {
"family": "Arzoumanian",
"given": "Z."
}
},
{
"id": "Altamirano-D",
"name": {
"family": "Altamirano",
"given": "D."
},
"orcid": "0000-0002-3422-0074"
}
]
},
"title": "Observations of the Ultra-compact X-Ray Binary 4U 1543-624 in Outburst with NICER, INTEGRAL, Swift, and ATCA",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 stars: neutron",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 June 18; revised 2019 July 26; accepted 2019 July 31; published 2019 September 18. \n\nThis work was supported by NASA through the NICER mission and the Astrophysics Explorers Program, and made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC). The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. R.M.L. acknowledges partial funding from a NASA Earth and Space Science Fellowship. E.M.C. gratefully acknowledges support through CAREER award number AST-1351222. M.F. acknowledges ASI financial/programmatic support via ASI-INAF agreement n. 2013-025.R1 and ASI-INAF N. 2017-14-H.0. J.A.G. acknowledges support from Chandra Theory grant TM8-19003X and from the Alexander von Humboldt Foundation. J.C.A. M.-J. is the recipient of an Australian Research Council Future Fellowship (FT 140101082), funded by the Australian Government.\n\nPublished - Ludlam_2019_ApJ_883_39.pdf
Accepted Version - 1908.00539.pdf
",
"abstract": "We report on X-ray and radio observations of the ultra-compact X-ray binary 4U 1543\u2212624 taken in August 2017 during an enhanced accretion episode. We obtained Neutron Star Interior Composition Explorer (NICER) monitoring of the source over a ~10 day period during which target-of-opportunity observations were also conducted with Swift, INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), and the Australia Telescope Compact Array. Emission lines were measured in the NICER X-ray spectrum at ~0.64 keV and ~6.4 keV that correspond to O and Fe, respectively. By modeling these line components, we are able to track changes in the accretion disk throughout this period. The innermost accretion flow appears to move inwards from hundreds of gravitational radii (R_g = GM/c^2) at the beginning of the outburst to <8.7 R g at peak intensity. We do not detect the source in radio, but are able to place a 3\u03c3 upper limit on the flux density at 27 \u03bcJy beam^(\u22121). Comparing the radio and X-ray luminosities, we find that the source lies significantly away from the range typical of black holes in the L_r-L_x plane, suggesting a neutron star primary. This adds to the evidence that neutron stars (NSs) do not follow a single track in the L_r-L_x plane, limiting its use in distinguishing between different classes of NSs based on radio and X-ray observations alone.",
"date": "2019-09-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "883",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 39",
"id_number": "CaltechAUTHORS:20190918-140450734",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190918-140450734",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Australian Government"
},
{
"agency": "NASA Earth and Space Science Fellowship"
},
{
"agency": "NSF",
"grant_number": "AST-1351222"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2013-025.R1"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
},
{
"agency": "NASA",
"grant_number": "TM8-19003X"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Australian Research Council",
"grant_number": "FT 140101082"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab3806",
"primary_object": {
"basename": "1908.00539.pdf",
"url": "https://authors.library.caltech.edu/records/9b3bb-dny67/files/1908.00539.pdf"
},
"related_objects": [
{
"basename": "Ludlam_2019_ApJ_883_39.pdf",
"url": "https://authors.library.caltech.edu/records/9b3bb-dny67/files/Ludlam_2019_ApJ_883_39.pdf"
}
],
"pub_year": "2019",
"author_list": "Ludlam, R. M.; Shishkovsky, L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0be4w-vzp04",
"eprint_id": 98660,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:49:58",
"lastmod": "2026-03-31 14:30:13",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Connors-R-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Sridhar-N",
"name": {
"family": "Sridhar",
"given": "Navin"
},
"orcid": "0000-0002-5519-9550"
},
{
"id": "Gatuzz-E",
"name": {
"family": "Gatuzz",
"given": "Efrain"
},
"orcid": "0000-0002-3252-9633"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John"
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Markoff-S-B",
"name": {
"family": "Markoff",
"given": "Sera B."
},
"orcid": "0000-0001-9564-0876"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Conflicting Disk Inclination Estimates for the Black Hole X-Ray Binary XTE J1500\u2212564",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 atomic processes \u2013 black hole physics",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 May 31; revised 2019 July 19; accepted 2019 July 23; published 2019 September 16. \n\nWe thank Kristin Madsen, Brian Grefenstette, Hiromasa Miyasaka, Yoshihiro Ueda, and Ken Ebisawa for very valuable discussions regarding the details of the X-ray data used in our analysis. \n\nJ.A.G. acknowledges support from NASA grant NNX15AV31G and the Alexander von Humboldt Foundation. R.M.T.C. has been supported by NASA grant 80NSSC177K0515. V.G. is supported through the Margarete von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg. \n\nThis research has made use of data, software, and/or web tools obtained from the High Energy Astrophysics Science Archive Research Center (HEASARC), a service of the Astrophysics Science Division at NASA/GSFC, and the Smithsonian Astrophysical Observatory's High Energy Astrophysics Division. \n\nThis work has also been conducted within the NuSTAR working group, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We are thankful for the support of its members in producing this research. \n\nFacility: RXTE - Rossi X-ray Timing Explorer (PCA, Jahoda et al. 1996; HEXTE, Rothschild et al. 1998), ASCA (GIS; Makishima et al. 1996), HEASARC. \n\nSoftware: XSPEC v.12.10.0c (Arnaud 1996), EMCEE (Foreman-Mackey et al. 2013b), XILLVER (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), RELXILL (v1.2.0; Dauser et al. 2014; Garc\u00eda et al. 2014).\n\nPublished - Connors_2019_ApJ_882_179.pdf
Submitted - 1907.12114.pdf
",
"abstract": "The dynamical characteristics of XTE J1550\u2212564, a black hole X-ray binary, are well established, and the broadband spectral evolution of the source has been well studied. Its orbital inclination is known to be high, at ~75\u00b0, with the jet estimated to align well with the orbital axis. We explore simultaneous observations made with the Advanced Satellite for Cosmology and Astrophysics and Rossi X-ray Timing Explorer covering the 1\u2013200 keV band during the early stages of the first outburst of XTE J1550\u2212564 in its hard-intermediate state on 1998 September 23/24. We show that the most up-to-date reflection models applied to these data yield an inclination estimate much lower than that found in previous studies at ~40\u00b0, grossly disagreeing with the dynamically estimated orbital inclination. We discuss the possible explanations for this disagreement and its implications for reflection models, including possible physical scenarios in which either the inner disk is misaligned with both the binary orbit and the outer jet or the inner accretion flow, corona, and/or jet have vertical structure that leads to lower inferred disk inclination through various physical means.",
"date": "2019-09-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "882",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 179",
"id_number": "CaltechAUTHORS:20190916-143938315",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190916-143938315",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX15AV31G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "European Social Fund"
},
{
"agency": "Ministry of Science, Research and the Arts (Baden-W\u00fcrttemberg)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab35df",
"primary_object": {
"basename": "1907.12114.pdf",
"url": "https://authors.library.caltech.edu/records/0be4w-vzp04/files/1907.12114.pdf"
},
"related_objects": [
{
"basename": "Connors_2019_ApJ_882_179.pdf",
"url": "https://authors.library.caltech.edu/records/0be4w-vzp04/files/Connors_2019_ApJ_882_179.pdf"
}
],
"pub_year": "2019",
"author_list": "Connors, Riley M. T.; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/1vxx0-cjb98",
"eprint_id": 97803,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:28:07",
"lastmod": "2026-03-31 05:34:25",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Casares-J",
"name": {
"family": "Casares",
"given": "J."
}
},
{
"id": "Jim\u00e9nez-Ibarra-F",
"name": {
"family": "Jim\u00e9nez-Ibarra",
"given": "F."
}
},
{
"id": "Mu\u00f1oz-Darias-T",
"name": {
"family": "Mu\u00f1oz-Darias",
"given": "T."
}
},
{
"id": "Armas-Padilla-M",
"name": {
"family": "Armas-Padilla",
"given": "M."
}
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
}
]
},
"title": "Dynamical confirmation of a black hole in MAXI J1820+070",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Astrophysical black holes; Low-mass X-ray binary stars; Stellar accretion disks; X-ray binary stars",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 July 8; revised 2019 July 25; accepted 2019 August 9; published 2019 September 6. \n\nWe are grateful to the GTC and ING staff, in particular Antonio L. Cabera Lavers and Ian Skillen, for their help to implement the observations presented in this work. We thank the referee for useful comments. We acknowledge support by the Spanish MINECO under grant AYA2017-83216-P. T.M.D. and M.A.P.T. acknowledge support via Ram\u00f3n y Cajal Fellowships RYC-2015-18148 and RYC-2015-17854. P.G.J. acknowledges funding from the European Research Council under ERC Consolidator grant agreement No. 647208. molly software developed by Tom Marsh is gratefully acknowledged. iraf is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. We dedicate this Letter to the memory of Jeff E. McClintock.\n\nPublished - Torres_2019_ApJL_882_L21.pdf
Accepted Version - 1907.00938.pdf
",
"abstract": "We present time-resolved 10.4 m Gran Telescopio Canarias and 4.2 m William Herschel Telescope intermediate resolution spectroscopy of the X-ray transient MAXI J1820+070 (=ASASSN-18ey) obtained during its decline to the quiescent state. Cross-correlation of the 21 individual spectra against late-type templates reveals a sinusoidal velocity modulation with a period of 0.68549 \u00b1 0.00001 day and semi-amplitude of 417.7 \u00b1 3.9 km s^(\u22121). We derive a mass function f(M) = 5.18 \u00b1 0.15 M\u2299, dynamically confirming the black hole (BH) nature of the compact object. Our analysis of the stellar absorption features supports a K3-5 spectral classification for the donor star, which contributes \u224820% of the total flux at 5200\u20136800 \u00c5. The photometric 0.703 \u00b1 0.003 day periodicity observed during outburst is 2.6% longer than the orbital period supporting the presence of a superhump modulation in the outburst light curves. In line with this interpretation, we constrain the binary mass ratio to be q \u2243 0.12. In addition, we observe a sharp increase in the H\u03b1 emission line equivalent width during inferior conjunction of the donor star that we interpret as a grazing eclipse of the accretion disk and allows us to constrain the binary inclination to i \u2273 69\u00b0. On the other hand, the absence of X-ray eclipses during outburst imply i \u227e 77\u00b0. These inclination limits, together with our dynamical solution, lead to a BH mass in the range 7\u20138 M\u2299. We also measure a systemic velocity \u03b3 = \u221221.6 \u00b1 2.3 km s^(\u22121), which, combined with the Gaia second data release proper motion and parallax, implies a large peculiar velocity ~100 km s^(\u22121).",
"date": "2019-09-10",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "882",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L21",
"id_number": "CaltechAUTHORS:20190812-160655506",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190812-160655506",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2017-83216-P"
},
{
"agency": "Ram\u00f3n y Cajal Fellowship",
"grant_number": "RYC-2015-18148"
},
{
"agency": "Ram\u00f3n y Cajal Fellowship",
"grant_number": "RYC-2015-17854"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/ab39df",
"primary_object": {
"basename": "1907.00938.pdf",
"url": "https://authors.library.caltech.edu/records/1vxx0-cjb98/files/1907.00938.pdf"
},
"related_objects": [
{
"basename": "Torres_2019_ApJL_882_L21.pdf",
"url": "https://authors.library.caltech.edu/records/1vxx0-cjb98/files/Torres_2019_ApJL_882_L21.pdf"
}
],
"pub_year": "2019",
"author_list": "Torres, M. A. P.; Casares, J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2tj66-ddk32",
"eprint_id": 97797,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:49:15",
"lastmod": "2026-03-31 16:00:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Masini-A",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Comastri-A",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Hickox-R-C",
"name": {
"family": "Hickox",
"given": "R. C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Civano-Francesca",
"name": {
"family": "Civano",
"given": "F."
},
"orcid": "0000-0002-2115-1137"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Brusa-Marcella",
"name": {
"family": "Brusa",
"given": "M."
},
"orcid": "0000-0002-5059-6848"
},
{
"id": "Lanzuisi-G",
"name": {
"family": "Lanzuisi",
"given": "G."
},
"orcid": "0000-0001-9094-0984"
}
]
},
"title": "Measuring the Obscuring Column of a Disk Megamaser AGN in a Nearby Merger",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 methods: observational \u2013 techniques: spectroscopic \u2013 X-rays: general",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 May 1; revised 2019 July 8; accepted 2019 July 11; published 2019 September 4. \n\nWe thank the anonymous referee for useful suggestions that improved the clarity of the paper, and M. Balokovi\u0107 for useful help and suggestions on Borus02 modeling. \n\nThis work was supported under NASA Contract NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has also made use of data obtained from the Chandra Data Archive and the Chandra Source Catalog, and software provided by the Chandra X-ray Center (CXC). A.M. and R.C.H. acknowledge support by the NSF through grant No. 1554584, and by NASA through grant No. NNX15AP24G and Chandra GO award GO7-18130X. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. A.C., M.B., and G.L. acknowledge support from the ASI/INAF grant I/037/12/0-011/13. \n\nFacilities: Chandra - , NuSTAR. - \n\nSoftware: CIAO (Fruscione et al. 2006), NuSTARDAS, XSPEC (Arnaud 1996).\n\nPublished - Masini_2019_ApJ_882_83.pdf
Submitted - 1907.05426.pdf
",
"abstract": "Active galactic nuclei (AGNs) hosting disk water megamasers are well known to be obscured by large amounts of gas, likely due to the presence along the line of sight of an almost edge-on disky structure orbiting the supermassive black hole. Correcting for the high obscuration is crucial to infer parameters intrinsic to the source, like its luminosity. We present a broadband X-ray spectral analysis of a water megamaser AGN in an early merger (NGC 5765B), combining Chandra and NuSTAR data. NGC 5765B is highly Compton-thick and reflection-dominated, following the general trend among disk megamasers. Combining the exquisite black hole mass from masers with our X-ray spectroscopy, the Eddington ratio of the megamaser is estimated to be in the 2%\u201314% range, and its robustness is confirmed through SED fitting.",
"date": "2019-09-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "882",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 83",
"id_number": "CaltechAUTHORS:20190812-145519174",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190812-145519174",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NSF",
"grant_number": "AST-1554584"
},
{
"agency": "NASA",
"grant_number": "NNX15AP24G"
},
{
"agency": "NASA",
"grant_number": "GO7-18130X"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0-011/13"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab3214",
"primary_object": {
"basename": "1907.05426.pdf",
"url": "https://authors.library.caltech.edu/records/2tj66-ddk32/files/1907.05426.pdf"
},
"related_objects": [
{
"basename": "Masini_2019_ApJ_882_83.pdf",
"url": "https://authors.library.caltech.edu/records/2tj66-ddk32/files/Masini_2019_ApJ_882_83.pdf"
}
],
"pub_year": "2019",
"author_list": "Masini, A.; Comastri, A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/pqtb9-1c684",
"eprint_id": 98601,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:46:11",
"lastmod": "2026-03-31 06:01:41",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hamden-E-T",
"name": {
"family": "Hamden",
"given": "Erika T."
}
},
{
"id": "Hoadley-K-L",
"name": {
"family": "Hoadley",
"given": "Keri"
},
"orcid": "0000-0002-8636-3309"
},
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "Christopher"
},
"orcid": "0000-0002-8650-1644"
},
{
"id": "Schiminovich-D",
"name": {
"family": "Schiminovich",
"given": "David"
}
},
{
"id": "Nikzad-S",
"name": {
"family": "Nikzad",
"given": "Shouleh"
}
},
{
"id": "Milliard-B",
"name": {
"family": "Milliard",
"given": "Bruno"
}
},
{
"id": "Kyne-G",
"name": {
"family": "Kyne",
"given": "Gillian"
}
}
]
},
"title": "2018 flight of the faint intergalactic medium redshifted emission balloon (FIREBall-2) (Conference Presentation)",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 Society of Photo-Optical Instrumentation Engineers (SPIE).",
"abstract": "In this talk, I will describe briefly the telescope, instrument, and flight of the Faint Intergalactic medium Redshifted Emission Balloon (FIREBall-2). FIREBall-2 is a UV multi-object spectrograph fed by a 1 meter parabola mirror. The instrument was designed to observe 4 pre-selected fields and uses a UV optimized delta-doped EMCCD. The telescope flew on September 22, 2018 from Fort Sumner, NM, as part of the fall CSBF balloon campaign. The telescope collected data for several night hours before being cut down. I will describe the testing, flight, and hardware performance with an emphasis on the in flight performance of the instrument, including resolution, throughput, and the overall operation of the UV optimized EMCCD. Additional talks will be presented on other aspects of the flight and data.",
"date": "2019-09-09",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 1111814",
"id_number": "CaltechAUTHORS:20190912-090006441",
"isbn": "9781510629295",
"book_title": "UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190912-090006441",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "Siegmund-O-H-W",
"name": {
"family": "Siegmund",
"given": "Oswald H."
}
}
]
},
"doi": "10.1117/12.2530083",
"pub_year": "2019",
"author_list": "Hamden, Erika T.; Hoadley, Keri; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4cqq5-fvw41",
"eprint_id": 98615,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:46:39",
"lastmod": "2024-01-14 21:56:38",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Smith-R-K",
"name": {
"family": "Smith",
"given": "Randall K."
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Arcus: the soft x-ray grating explorer",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nThe research leading to these results has in part received funding from NASA contract 80ARC018C0002 (Arcus Phase A) and the Smithsonian Astrophysical Observatory. SRON is supported financially by NWO, the Netherlands Organization for Scientific Research.\n\nPublished - 111180W.pdf
",
"abstract": "Arcus provides high-resolution soft X-ray spectroscopy in the 12-50 \u00c5 bandpass with unprecedented sensitivity, including spectral resolution < 2500 and effective area < 250 cm^2. The three top science goals for Arcus are (1) to measure the effects of structure formation imprinted upon the hot baryons that are predicted to lie in extended halos around galaxies, (2) to trace the propagation of outflowing mass, energy, and momentum from the vicinity of the black hole to extragalactic scales as a measure of their feedback, and (3) to explore how stars form and evolve. Arcus uses the same 12 m focal length grazing-incidence Silicon Pore X-ray Optics (SPOs) that ESA has developed for the Athena mission; the focal length is achieved on orbit via an extendable optical bench. The focused X-rays from these optics are diffracted by high-efficiency Critical-Angle Transmission (CAT) gratings, and the results are imaged with flight-proven CCD detectors and electronics. Combined with the high-heritage NGIS LEOStar-2 spacecraft and launched into 4:1 lunar resonant orbit, Arcus provides high sensitivity and high efficiency observing of a wide range of astrophysical sources.",
"date": "2019-09-09",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 111180W",
"id_number": "CaltechAUTHORS:20190912-133335405",
"isbn": "9781510629295",
"book_title": "UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190912-133335405",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80ARC018C0002"
},
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "Siegmund-O-H-W",
"name": {
"family": "Siegmund",
"given": "Oswald H."
}
}
]
},
"doi": "10.1117/12.2529499",
"primary_object": {
"basename": "111180W.pdf",
"url": "https://authors.library.caltech.edu/records/4cqq5-fvw41/files/111180W.pdf"
},
"pub_year": "2019",
"author_list": "Smith, Randall K. and Madsen, Kristin"
},
{
"id": "https://authors.library.caltech.edu/records/3ae0p-tys05",
"eprint_id": 98602,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:46:14",
"lastmod": "2026-03-31 05:58:42",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kyne-G",
"name": {
"family": "Kyne",
"given": "Gillian"
}
},
{
"id": "Hamden-E-T",
"name": {
"family": "Hamden",
"given": "Erika T."
}
},
{
"id": "Hoadley-K-L",
"name": {
"family": "Hoadley",
"given": "Keri"
},
"orcid": "0000-0002-8636-3309"
},
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "Christopher"
},
"orcid": "0000-0002-8650-1644"
},
{
"id": "Nikzad-S",
"name": {
"family": "Nikzad",
"given": "Shouleh"
}
},
{
"id": "Jewell-A-D",
"name": {
"family": "Jewell",
"given": "April"
},
"orcid": "0000-0001-8834-3769"
}
]
},
"title": "Ground- and space-based UV observations with EMCCDs (Conference Presentation)",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 Society of Photo-Optical Instrumentation Engineers (SPIE).",
"abstract": "I will present on-going detector developments in our joint NASA/CNES balloon-borne UV multi-object spectrograph, FIREBall-2, the Faint Intergalactic Redshifted Emission Balloon. FIREBall-2 is a path finding mission to test new technology (EMCCDs) and make new constraints on the temperature and density of this gas. This instrument has been designed to detect faint emission from the circumgalactic medium (CGM) around low redshift galaxies (z ~ 0.7). One major change from FIREBall-1 has been the use of a delta-doped Electron Multiplying CCD (EMCCD). EMCCDs can be used in photon-counting (PC) mode to achieve extremely low readout noise (< 1 electron). Our testing initially focused on reducing clock-induced-charge (CIC) through wave shaping and well depth optimisation with a NuVu CCD Controller for Counting Photons (CCCP). This optimisation also includes methods for reducing dark current, via cooling, and exploring substrate voltage levels. I will present some of our dark current results from laboratory testing. We recently launched FIREBall-2 from Fort Sumner, New Mexico on September 22nd, 2018. This was the first time an EMCCD has been used for UV/optical observations in flight! I will present performance data from the flight including cosmic ray rate measurements, and some of our preliminary on-sky UV results using our data reduction.",
"date": "2019-09-09",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 111150B",
"id_number": "CaltechAUTHORS:20190912-091213260",
"isbn": "9781510629233",
"book_title": "UV/Optical/IR Space Telescopes and Instruments: Innovative Technologies and Concepts IX",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190912-091213260",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "Barto-A-A",
"name": {
"family": "Barto",
"given": "Allison A."
}
},
{
"id": "Breckinridge-J-B",
"name": {
"family": "Breckinridge",
"given": "James B."
}
},
{
"id": "Stahl-H-P",
"name": {
"family": "Stahl",
"given": "H. Philip"
}
}
]
},
"doi": "10.1117/12.2530520",
"pub_year": "2019",
"author_list": "Kyne, Gillian; Hamden, Erika T.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/qzbms-fkx32",
"eprint_id": 98629,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:48:08",
"lastmod": "2026-03-31 15:48:01",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hoadley-K-L",
"name": {
"family": "Hoadley",
"given": "Keri"
},
"orcid": "0000-0002-8636-3309"
},
{
"id": "Hamden-E-T",
"name": {
"family": "Hamden",
"given": "Erika T."
}
},
{
"id": "Milliard-B",
"name": {
"family": "Milliard",
"given": "Bruno"
}
},
{
"id": "Khan-A-R",
"name": {
"family": "Khan",
"given": "Aafaque R."
}
},
{
"id": "Agarwal-S",
"name": {
"family": "Agarwal",
"given": "Simran"
}
},
{
"id": "Lin-Zeren",
"name": {
"family": "Lin",
"given": "Zeren"
}
},
{
"id": "Schiminovich-D",
"name": {
"family": "Schiminovich",
"given": "David"
}
},
{
"id": "Kyne-G",
"name": {
"family": "Kyne",
"given": "Gillian"
}
},
{
"id": "Evrard-J",
"name": {
"family": "Evrard",
"given": "Jean"
}
},
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "D. Christopher"
},
"orcid": "0000-0002-8650-1644"
}
]
},
"title": "The FIREBall-2 UV balloon telescope: 2018 flight and improvements for 2020",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "Scientific Ballooning, CGM, Galaxy Evolution, Optical Alignment",
"note": "\u00a9 2019 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nThis work was funded primarily through the APRA program for sub-orbital missions which funds the US side of FIREBall. CNES and CNRS provided support for the French side of the FIREBall collaboration. Dr. Hoadley is supported through the David & Ellen Lee Prize Postdoctoral Fellowship in Experimental Physics at Caltech. The FIREBall-2 collaboration would like thank the Columbia Scientific Ballooning Facility (CSBF) and Balloon Program Office (BPO/NASA) for their support throughout the 2017/2018 campaigned in Ft. Sumner, NM.\n\nPublished - 1111815.pdf
",
"abstract": "The Faint Intergalactic-medium Redshifted Emission Balloon (FIREBall-2, FB-2) is designed to discover and map faint UV emission from the circumgalactic medium around low redshift galaxies (z ~ 0.3 (C IV); z ~ 0.7 (Ly\u03b1); z ~ 1.0 (O VI)). FIREBall-2's first launch, on September 22nd 2018 out of Ft. Sumner, NM, was abruptly cut short due to a hole that developed in the balloon. FIREBall-2 was unable to observe above its minimum require altitude (25 km; nominal: 32 km) for its shortest required time (2 hours; nominal: 8+ hours). The shape of the deflated balloon, as well as a concurrent full moon close to our observed target field, revealed a severe, off-axis scattered light path directly to the UV science detector. Additional damage to FB-2 added complications to the ongoing effort to prepare FB-2 for a quick re-flight. Upon landing, several mirrors in the optical chain, including the two large telescope mirrors, were damaged, resulting in chunks of material broken off the sides and reflecting surfaces. The magnifying optical element, called the focal corrector, was discovered to be misaligned beyond tolerance after the 2018 flight, with one of its two mirrors damaged from the landing impact. We describe the steps taken thus far to mitigate the damage to the optics, as well as procedures and results from the ongoing efforts to re-align the focal corrector and spectrograph optics. We report the throughput of the spectrograph before and after the 2018 flight and plans for improving it. Finally, we describe several methods by which we address the scattered light issues seen from FIREBall-2's 2018 campaign and present the current status of FB-2 to fly during the summer campaign in Palestine, TX in 2020.",
"date": "2019-09-09",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 1111815",
"id_number": "CaltechAUTHORS:20190913-080236356",
"isbn": "9781510629295",
"book_title": "UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190913-080236356",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Advanced Research Projects Agency (ARPA)"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "David and Ellen Lee Postdoctoral Scholarship"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "Siegmund-O-H-W",
"name": {
"family": "Siegmund",
"given": "Oswald H."
}
}
]
},
"doi": "10.1117/12.2530047",
"primary_object": {
"basename": "1111815.pdf",
"url": "https://authors.library.caltech.edu/records/qzbms-fkx32/files/1111815.pdf"
},
"pub_year": "2019",
"author_list": "Hoadley, Keri; Hamden, Erika T.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/a5d9h-sj227",
"eprint_id": 98390,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:25:18",
"lastmod": "2026-03-30 23:43:52",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ghanbari-K",
"name": {
"family": "Ghanbari",
"given": "Keyvan"
}
},
{
"id": "Florinski-V",
"name": {
"family": "Florinski",
"given": "Vladimir"
},
"orcid": "0000-0001-5485-2872"
},
{
"id": "Guo-Xiaocheng",
"name": {
"family": "Guo",
"given": "Xiaocheng"
},
"orcid": "0000-0003-0541-0597"
},
{
"id": "Hu-Qiang",
"name": {
"family": "Hu",
"given": "Qiang"
},
"orcid": "0000-0002-7570-2301"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "Richard"
},
"orcid": "0000-0002-0156-2414"
}
]
},
"title": "Galactic Cosmic Rays Modulation in the Vicinity of Corotating Interaction Regions: Observations During the Last Two Solar Minima",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galactic cosmic rays; solar wind; corotating streams; interplanetary turbulence",
"note": "\u00a9 2019. The American Astronomical Society. \n\nReceived 2019 June 16; revised 2019 July 10; accepted 2019 July 10; published 2019 September 2. \n\nThis research was supported by NASA grant NNX17AB85G. The authors appreciate being granted access to the OMNI data obtained through the GSFC/SPDF OMNIWeb interface at (http://omniweb.gsfc.nasa.gov).\n\nPublished - Ghanbari_2019_ApJ_882_54.pdf
",
"abstract": "Corotating interaction regions (CIRs) are responsible for short-term recurrent cosmic-ray modulation, prominent near solar minima. Using the OMNI data sets for two periods of low solar activity near the beginning and end of solar cycle 24, superposed epoch analysis was performed on the solar wind plasma features for 53 and 43 events during periods 2007\u20132008 and 2017\u20132018, respectively. Turbulent properties of the solar wind were studied using the variance method for each CIR. Power spectra have been constructed for overlapped subintervals in the vicinity of stream interfaces (SIs). Using measured correlation lengths and turbulent energies, parallel and perpendicular diffusion mean free paths for cosmic-ray ions have been inferred based on two distinct theoretical formulations. For the two periods with opposite solar polarities, our results show that unlike solar wind speed, magnetic field strength, flow pressure, and proton density are relatively higher during the latest period. Increased turbulent energy and reduced parallel transport coefficients of energetic particles at the SIs are observed. The diffusion coefficients follow the same trends during both periods. The perpendicular diffusion starts increasing nearly a day before SIs and is higher in the fast wind. Superposed epoch analysis is performed on the >120 MeV proton count rate obtained from the CRIS instrument on board the ACE spacecraft for the same events. The recorded proton rates have peaks half a day before a SI and reach their minimum more than a day after a SI and have a high anticorrelation with the perpendicular diffusion coefficient.",
"date": "2019-09-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "882",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 54",
"id_number": "CaltechAUTHORS:20190903-130240306",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190903-130240306",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX17AB85G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab31a5",
"primary_object": {
"basename": "Ghanbari_2019_ApJ_882_54.pdf",
"url": "https://authors.library.caltech.edu/records/a5d9h-sj227/files/Ghanbari_2019_ApJ_882_54.pdf"
},
"pub_year": "2019",
"author_list": "Ghanbari, Keyvan; Florinski, Vladimir; et al."
},
{
"id": "https://authors.library.caltech.edu/records/81gjb-q9404",
"eprint_id": 98418,
"eprint_status": "archive",
"datestamp": "2023-08-22 02:25:47",
"lastmod": "2026-03-31 15:53:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Vievering-Juliana-T",
"name": {
"family": "Vievering",
"given": "Juliana T."
},
"orcid": "0000-0002-7407-6740"
},
{
"id": "Glesener-Lindsay",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Smith-David-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
}
]
},
"title": "New Star Observations with NuSTAR: Flares from Young Stellar Objects in the \u03c1 Ophiuchi Cloud Complex in Hard X-Rays",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Star forming regions; Stellar flares; Stellar x-ray flares; Pre-main sequence stars; Young stellar objects; Stellar activity",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 October 25; revised 2019 June 7; accepted 2019 June 26; published 2019 September 4. \n\nThis work was supported by NSF grants AGS-1429512 and AGS-1752268 and by NASA Headquarters under the NASA Earth and Space Science Fellowship Program Grant 80NSSC17K0430. The authors would like to acknowledge and thank Eric Feigelson for encouraging the NuSTAR team early on to make these observations and for contributing to discussions of this analysis. \n\nSoftware: NuSTARDAS (v1.6.0), nuskybgd (Wik et al. 2014), XSPEC (Arnaud 1996).\n\nPublished - Vievering_2019_ApJ_882_72.pdf
",
"abstract": "We study the structure and dynamics of extreme flaring events on young stellar objects (YSOs) observed in hard X-rays by the Nuclear Spectroscopic Telescope Array (NuSTAR). During 2015 and 2016, NuSTAR made three observations of the star-forming region \u03c1 Ophiuchi, each with an exposure ~50 ks. NuSTAR offers unprecedented sensitivity above ~7 keV, making this data set the first of its kind. Through improved coverage of hard X-rays, it is finally possible to directly measure the high-energy thermal continuum for hot plasmas and to sensitively search for evidence of nonthermal emission from YSO flares. During these observations, multiple flares were observed, and spectral and timing analyses were performed on three of the brightest flares. By fitting an optically thin thermal plasma model to each of these events, we found flare plasma heated to high temperatures (~40\u221280 MK) and determined that these events are ~1000 times brighter than the brightest flares observed on the Sun. Two of the studied flares showed excess emission at 6.4 keV, and this excess may be attributable to iron fluorescence in the circumstellar disk. No clear evidence for a nonthermal component was observed, but upper limits on nonthermal emission allow for enough nonthermal energy to account for the estimated thermal energy in the flare on protostar IRS 43, which is consistent with the standard model for solar and stellar flares.",
"date": "2019-09-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "882",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 72",
"id_number": "CaltechAUTHORS:20190904-152822673",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190904-152822673",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "AGS-1429512"
},
{
"agency": "NSF",
"grant_number": "AGS-1752268"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "80NSSC17K0430"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab2e0d",
"pmcid": "PMC8780732",
"primary_object": {
"basename": "Vievering_2019_ApJ_882_72.pdf",
"url": "https://authors.library.caltech.edu/records/81gjb-q9404/files/Vievering_2019_ApJ_882_72.pdf"
},
"pub_year": "2019",
"author_list": "Vievering, Juliana T.; Glesener, Lindsay; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2kcz7-hqx13",
"eprint_id": 94914,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:32:45",
"lastmod": "2026-03-31 05:22:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "D. Christopher"
},
"orcid": "0000-0002-8650-1644"
},
{
"id": "O'Sullivan-Donal",
"name": {
"family": "O'Sullivan",
"given": "Donal"
},
"orcid": "0000-0002-4959-9179"
},
{
"id": "Matuszewski-M",
"name": {
"family": "Matuszewski",
"given": "Mateusz"
}
},
{
"id": "Hamden-E-T",
"name": {
"family": "Hamden",
"given": "Erika T."
}
},
{
"id": "Dekel-Avishai",
"name": {
"family": "Dekel",
"given": "Avishai"
},
"orcid": "0000-0003-4174-0374"
},
{
"id": "Lapiner-Sharon",
"name": {
"family": "Lapiner",
"given": "Sharon"
}
},
{
"id": "Morrissey-P",
"name": {
"family": "Morrissey",
"given": "Patrick"
},
"orcid": "0000-0001-8177-1023"
},
{
"id": "Neill-J-D",
"name": {
"family": "Neill",
"given": "James D."
},
"orcid": "0000-0002-0466-1119"
},
{
"id": "Cantalupo-S",
"name": {
"family": "Cantalupo",
"given": "Sebastiano"
},
"orcid": "0000-0001-5804-1428"
},
{
"id": "Prochaska-J-X",
"name": {
"family": "Prochaska",
"given": "Jason Xavier"
},
"orcid": "0000-0002-7738-6875"
},
{
"id": "Steidel-C-C",
"name": {
"family": "Steidel",
"given": "Charles"
},
"orcid": "0000-0002-4834-7260"
},
{
"id": "Trainor-R-F",
"name": {
"family": "Trainor",
"given": "Ryan"
},
"orcid": "0000-0002-6967-7322"
},
{
"id": "Moore-A-M",
"name": {
"family": "Moore",
"given": "Anna"
},
"orcid": "0000-0002-2894-6936"
},
{
"id": "Ceverino-D",
"name": {
"family": "Ceverino",
"given": "Daniel"
},
"orcid": "0000-0002-8680-248X"
},
{
"id": "Primack-J-R",
"name": {
"family": "Primack",
"given": "Joel"
},
"orcid": "0000-0001-5091-5098"
},
{
"id": "Rizzi-L",
"name": {
"family": "Rizzi",
"given": "Luca"
},
"orcid": "0000-0003-0882-2327"
}
]
},
"title": "Multi-filament gas inflows fuelling young star-forming galaxies",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2019 Springer Nature Publishing AG. \n\nReceived 07 March 2019. Accepted 25 April 2019. Published 01 July 2019. \n\nThis work was supported by the National Science Foundation, the W. M. Keck Observatory and the California Institute of Technology. The VELA simulations were performed at NASA Advanced Supercomputing at NASA Ames Research Center. D.C. is funded by the ERC Advanced Grant, STARLIGHT: Formation of the First Stars (project number 339177). \n\nAuthor Contributions: D.C.M. is the Principal Investigator of KCWI, performed the analysis of the simulated galaxy, data and MFI models, and was principal author on the paper. D.O. and D.C.M. led the observations of UM287 and CSO 38. D.O. and M.M. reduced the data. D.O., M.M. and E.H. contributed to the paper writing. P.M., M.M., D.C.M., J.D.N., D.O. and A.M. designed, constructed and operated KCWI. J.D.N., M.M. and D.C.M. developed the KCWI data pipeline and produced the final data cubes. D.C. developed the VELA simulations. A.D. and S.L. provided the simulated galaxy VELA07 and contributed to the writing of the paper. D.C. and J.P. contributed the cosmological simulation. C.S., R.T., S.C. and J.X.P. contributed to the development of KCWI, to Keck data for the two protogalaxies, and to the editing of the paper. L.R. made major contributions to KCWI commissioning and participated in the observations of CSO 38. \n\nData availability: KCWI data on CSO38 and UM287 is publicly available. Data on UM287 will be available 18 months after the observation in Oct 2017. The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. \n\nCode availability: KCWI pipeline code is available on the W. M. Keck Observatory website. The authors declare no competing interests.\n\nAccepted Version - 1904.11465.pdf
Supplemental Material - 41550_2019_791_MOESM1_ESM.pdf
",
"abstract": "Theory suggests that there are two primary modes of accretion through which dark-matter halos acquire the gas to form and fuel galaxies: hot- and cold-flow accretion. In cold-flow accretion, gas streams along cosmic web filaments to the centre of the halo, allowing for the efficient delivery of star-forming fuel. Recently, two quasar-illuminated H\u2009I Lyman \u0251 (Ly\u03b1)-emitting objects were reported to have properties of cold, rotating structures. However, the spatial and spectral resolution available was insufficient to constrain the radial flows associated with connecting filaments. With the Keck Cosmic Web Imager (KCWI), we now have eight times the spatial resolution, permitting the detection of these inspiralling flows. To detect these inflows, we introduce a suite of models that incorporate zonal radial flows, demonstrate their performance on a numerical simulation that exhibits cold-flow accretion, and show that they are an excellent match to KCWI velocity maps of two Ly\u03b1 emitters observed around high-redshift quasars. These multi-filament inflow models kinematically isolate zones of radial inflow that correspond to extended filamentary emission. The derived gas flux and inflow path is sufficient to fuel the inferred central galaxy star-formation rate and angular momentum. Thus, our kinematic emission maps provide strong evidence that the inflow of gas from the cosmic web is building galaxies at the peak of star formation.",
"date": "2019-09",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "3",
"number": "9",
"publisher": "Nature Publishing Group",
"pagerange": "822-831",
"id_number": "CaltechAUTHORS:20190424-101356136",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190424-101356136",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF"
},
{
"agency": "W. M. Keck Observatory"
},
{
"agency": "Caltech"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "339177"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1038/s41550-019-0791-2",
"primary_object": {
"basename": "1904.11465.pdf",
"url": "https://authors.library.caltech.edu/records/2kcz7-hqx13/files/1904.11465.pdf"
},
"related_objects": [
{
"basename": "41550_2019_791_MOESM1_ESM.pdf",
"url": "https://authors.library.caltech.edu/records/2kcz7-hqx13/files/41550_2019_791_MOESM1_ESM.pdf"
}
],
"pub_year": "2019",
"author_list": "Martin, D. Christopher; O'Sullivan, Donal; et al."
},
{
"id": "https://authors.library.caltech.edu/records/09k36-2e445",
"eprint_id": 97725,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:35:32",
"lastmod": "2026-03-31 14:19:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Sathyaprakash-Rajath",
"name": {
"family": "Sathyaprakash",
"given": "R."
},
"orcid": "0000-0002-5254-3969"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "Fuerst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Pinto-Ciro",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Alston-William-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Fabian-Andrew-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Soria-Roberto",
"name": {
"family": "Soria",
"given": "R."
},
"orcid": "0000-0002-4622-796X"
}
]
},
"title": "The discovery of weak coherent pulsations in the ultraluminous X-ray source NGC 1313 X-2",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013 X-rays: binaries",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 May 30. Received 2019 May 28; in original form 2019 April 11. Published: 02 July 2019. \n\nThe authors wish to thank the referee for their useful comments that helped improve this paper. RS is grateful for the studentship from the STFC (ST/N50404X/1). TPR was funded as part of the STFC consolidated grant ST/K000861/1. HPE acknowledges support under NASA contract NNG08FD60C. CP is thankful for an ESA Research Fellowship, and DJW acknowledges support from an STFC ERF. This work is based on observations obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.\n\nPublished - slz086.pdf
Accepted Version - 1906.00640.pdf
",
"abstract": "We report the detection of weak pulsations from the archetypal ultraluminous X-ray source (ULX) NGC 1313 X-2. Acceleration searches reveal sinusoidal pulsations in segments of two out of six new deep observations of this object, with a period of \u223c1.5 s and a pulsed fraction of \u223c5 per cent\u2060. We use Monte Carlo simulations to demonstrate that the individual detections are unlikely to originate in false Poisson noise detections given their very close frequencies; their strong similarity to other pulsations detected from ULXs also argues they are real. The presence of a large bubble nebula surrounding NGC 1313 X-2 implies an age of order 1 Myr for the accreting phase of the ULX, which implies that the neutron star's (NS) magnetic field has not been suppressed over time by accreted material, nor has the NS collapsed into a black hole, despite an average energy output into the nebula two orders of magnitude above Eddington. This argues that most of the accreted material has been expelled over the lifetime of the ULX, favouring physical models including strong winds and/or jets for NS ULXs.",
"date": "2019-09",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society: Letters",
"volume": "488",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "L35-L40",
"id_number": "CaltechAUTHORS:20190809-141259403",
"issn": "1745-3925",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190809-141259403",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/N50404X/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K000861/1"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnrasl/slz086",
"primary_object": {
"basename": "1906.00640.pdf",
"url": "https://authors.library.caltech.edu/records/09k36-2e445/files/1906.00640.pdf"
},
"related_objects": [
{
"basename": "slz086.pdf",
"url": "https://authors.library.caltech.edu/records/09k36-2e445/files/slz086.pdf"
}
],
"pub_year": "2019",
"author_list": "Sathyaprakash, R.; Roberts, T. P.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/qhrb3-4a778",
"eprint_id": 97734,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:35:39",
"lastmod": "2026-03-31 16:03:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Buchner-J",
"name": {
"family": "Buchner",
"given": "Johannes"
},
"orcid": "0000-0003-0426-6634"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Nandra-K",
"name": {
"family": "Nandra",
"given": "Kirpal"
},
"orcid": "0000-0002-7150-9192"
},
{
"id": "Nikutta-R",
"name": {
"family": "Nikutta",
"given": "Robert"
},
"orcid": "0000-0002-7052-6900"
},
{
"id": "Bauer-F-E",
"name": {
"family": "Bauer",
"given": "Franz E."
},
"orcid": "0000-0002-8686-8737"
}
]
},
"title": "X-ray spectral and eclipsing model of the clumpy obscurer in active galactic nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 X-rays: galaxies \u2013 methods: numerical",
"note": "\u00a9 2019 ESO. Article published by EDP Sciences. \n\nReceived 3 December 2018; Accepted 18 July 2019; Published online 27 August 2019. \n\nWe thank the anonymous referee for careful reading of the manuscript and their insightful comments. JB thanks Marc Schartmann and Leonard Burtscher for discussions on tori in the infrared. JB thanks Eva Lefa for sharing her Monte Carlo code to verify our Compton scattering implementation. JB thanks Mislav Balokovi\u0107 for insightful conversations. We acknowledge support from the CONICYT-Chile grants Basal-CATA PFB-06/2007 & AFB-170002 (JB, FEB), FONDECYT Regular 1141218 (FEB), FONDECYT Postdoctorados 3160439 (JB) and the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS (JB, FEB). This research was supported by the DFG cluster of excellence \"Origin and Structure of the Universe\".\n\nPublished - aa34771-18.pdf
Submitted - 1907.13137.pdf
",
"abstract": "We present a unification model for a clumpy obscurer in active galactic nuclei (AGN) and investigate the properties of the resulting X-ray spectrum. Our model is constructed to reproduce the column density distribution of the AGN population and cloud eclipse events in terms of their angular sizes and frequency. We developed and released a generalised Monte Carlo X-ray radiative transfer code, XARS, to compute X-ray spectra of obscurer models. The geometry results in strong Compton scattering, causing soft photons to escape also along Compton-thick sight lines. This makes our model spectra very similar to our TORUS previous model. However, only if we introduce an additional Compton-thick reflector near the corona, we achieve good fits to NuSTAR spectra. This additional component in our model can be interpreted as part of the dust-free broad-line region, an inner wall or rim, or a warped disk. It cannot be attributed to a simple disk because the reflector must simultaneously block the line of sight to the corona and reflect its radiation. We release our model as an Xspec table model and present corresponding CLUMPY infrared spectra, paving the way for self-consistent multi-wavelength analyses.",
"date": "2019-09",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "629",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A16",
"id_number": "CaltechAUTHORS:20190809-153450175",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190809-153450175",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Basal-CATA",
"grant_number": "PFB-06/2007"
},
{
"agency": "Basal-CATA",
"grant_number": "AFB-170002"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1141218"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3160439"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/201834771",
"primary_object": {
"basename": "1907.13137.pdf",
"url": "https://authors.library.caltech.edu/records/qhrb3-4a778/files/1907.13137.pdf"
},
"related_objects": [
{
"basename": "aa34771-18.pdf",
"url": "https://authors.library.caltech.edu/records/qhrb3-4a778/files/aa34771-18.pdf"
}
],
"pub_year": "2019",
"author_list": "Buchner, Johannes; Brightman, Murray; et al."
},
{
"id": "https://authors.library.caltech.edu/records/17s09-jwc60",
"eprint_id": 97434,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:23:48",
"lastmod": "2026-03-31 16:01:42",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Paliya-V-S",
"name": {
"family": "Paliya",
"given": "Vaidehi S."
},
"orcid": "0000-0001-7774-5308"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Trakhtenbrot-B",
"name": {
"family": "Trakhtenbrot",
"given": "B."
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "K."
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Ajello-M",
"name": {
"family": "Ajello",
"given": "M."
},
"orcid": "0000-0002-6584-1703"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Powell-M-C",
"name": {
"family": "Powell",
"given": "M. C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Urry-C-M",
"name": {
"family": "Urry",
"given": "C. M."
},
"orcid": "0000-0002-0745-9792"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Lamperti-I",
"name": {
"family": "Lamperti",
"given": "I."
},
"orcid": "0000-0003-3336-5498"
},
{
"id": "Mushotzky-R-F",
"name": {
"family": "Mushotzky",
"given": "R."
},
"orcid": "0000-0002-7962-5446"
},
{
"id": "Marcotulli-L",
"name": {
"family": "Marcotulli",
"given": "L."
}
},
{
"id": "Mej\u00eda-Restrepo-J-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "J."
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Hartmann-D-H",
"name": {
"family": "Hartmann",
"given": "D."
}
}
]
},
"title": "BAT AGN Spectroscopic Survey: XVI. General Physical Characteristics of BAT Blazars",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: jets",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 May 28; revised 2019 June 24; accepted 2019 July 1; published 2019 August 22. \n\nWe are grateful to the journal referee for a constructive criticism. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. C.R. acknowledges support from the CONICYT+PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080. K.O. is an International Research Fellow of the Japan Society for the Promotion of Science (JSPS, ID: P17321). We are grateful to the Fermi-LAT Collaboration internal referee Raniere Menezes for useful suggestions and Alberto Dom\u00ednguez, Judith Recusin and Philippe Bruel for their critical reading of the manuscript. The Fermi LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analyses. These include the National Aeronautics and Space Administration and the Department of Energy in the United States; the Commissariat \u00e0 l'Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucl\u00e9aire et de Physique des Particules in France; the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy; the Ministry of Education, Culture, Sports, Science and Technology (MEXT); High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan; and the K. A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d'\u00c9tudes Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515. We acknowledge the work of the Swift-BAT team to make this study possible. \n\nThis research has made use of data obtained through the High Energy Astrophysics Science Archive Research Center Online Service, provided by the NASA/Goddard Space Flight Center. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. Part of this work is based on archival data, software, or online services provided by the ASI Data Center (ASDC). \n\nSoftware: fermiPy (Wood et al. 2017).\n\nPublished - Paliya_2019_ApJ_881_154.pdf
Submitted - 1907.01082.pdf
",
"abstract": "The recently released 105-month Swift-Burst Alert Telescope (BAT) all-sky hard X-ray survey catalog presents an opportunity to study astrophysical objects detected in the deepest look at the entire hard X-ray (14\u2013195 keV) sky. Here we report the results of a multifrequency study of 146 blazars from this catalog, quadrupling the number compared to past studies, by utilizing recent data from the Fermi-Large Area Telescope (LAT), Swift-BAT, and archival measurements. In our \u03b3-ray analysis of ~10 yr of the LAT data, 101 are found as \u03b3-ray emitters, whereas, 45 remains LAT undetected. We model the broadband spectral energy distributions with a synchrotron-inverse Compton radiative model. On average, BAT detected sources host massive black holes (M_(bh) ~ 10^9 M \u2299) and luminous accretion disks (L_d ~ 10^(46) erg s^(\u22121)). At high redshifts (z > 2), BAT blazars host more powerful jets with luminous accretion disks compared to those detected only with Fermi-LAT. We find good agreement in the black hole masses derived from the single-epoch optical spectroscopic measurements and standard accretion disk modeling approaches. Other physical properties of BAT blazars are similar to those known for Fermi-LAT detected objects.",
"date": "2019-08-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "881",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 154",
"id_number": "CaltechAUTHORS:20190726-091428531",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190726-091428531",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PAI77170080"
},
{
"agency": "Japan Society for the Promotion of Science (JSPS)",
"grant_number": "P17321"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC02-76SF00515"
},
{
"agency": "Commissariat \u00e0 l'Energie Atomique (CEA)"
},
{
"agency": "Centre National de la Recherche Scientifique (CNRS)"
},
{
"agency": "Institut National de Physique Nucl\u00e9aire et de Physique des Particules (IN2P3)"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)"
},
{
"agency": "High Energy Accelerator Research Organization (KEK)"
},
{
"agency": "Japan Aerospace Exploration Agency (JAXA)"
},
{
"agency": "Knut and Alice Wallenberg Foundation"
},
{
"agency": "Swedish Research Council"
},
{
"agency": "Swedish National Space Board (SNSB)"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab2f8b",
"primary_object": {
"basename": "1907.01082.pdf",
"url": "https://authors.library.caltech.edu/records/17s09-jwc60/files/1907.01082.pdf"
},
"related_objects": [
{
"basename": "Paliya_2019_ApJ_881_154.pdf",
"url": "https://authors.library.caltech.edu/records/17s09-jwc60/files/Paliya_2019_ApJ_881_154.pdf"
}
],
"pub_year": "2019",
"author_list": "Paliya, Vaidehi S.; Koss, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/v3ayc-8xq09",
"eprint_id": 97866,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:23:55",
"lastmod": "2026-03-31 14:05:29",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hannah-I-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Kleint-L",
"name": {
"family": "Kleint",
"given": "Lucia"
}
},
{
"id": "Krucker-S",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
}
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Glesener-L",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Hudson-H-S",
"name": {
"family": "Hudson",
"given": "Hugh S."
},
"orcid": "0000-0001-5685-1283"
},
{
"id": "White-S-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
},
{
"id": "Smith-D-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
}
]
},
"title": "Joint X-ray, EUV and UV Observations of a Small Microflare",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: activity \u2013 Sun: corona \u2013 Sun: transition region \u2013 Sun: UV radiation \u2013 Sun: X-rays, gamma rays",
"note": "\u00a9 2019 The American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2018 December 21; revised 2019 June 20; accepted 2019 June 28; published 2019 August 20. \n\nThis paper made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NUSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy), and the California Institute of Technology (USA). \n\nIRIS is a NASA small explorer mission developed and operated by LMSAL with mission operations executed at NASA Ames Research center and major contributions to downlink communications funded by ESA and the Norwegian Space Centre. \n\nI.G.H. is supported by a Royal Society University Fellowship. The authors thank the International Space Science Institute (ISSI) for support for P. Testa's team \"New Diagnostics of Particle Acceleration in Solar Coronal Nanoflares from Chromospheric Observations and Modeling,\" where this work benefited from productive discussions. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, IRIS - , SDO/AIA - , GOES. -\n\nPublished - Hannah_2019_ApJ_881_109.pdf
Accepted Version - 1812.09214.pdf
",
"abstract": "We present the first joint observation of a small microflare in X-rays with the Nuclear Spectroscopic Telescope ARray (NuSTAR), in UV with the Interface Region Imaging Spectrograph (IRIS), and in EUV with the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA). These combined observations allow us to study the hot coronal and cooler chromospheric/transition region emission from the microflare. This small microflare peaks from 2016 July 26 23:35 to 23:36 UT, in both NuSTAR, SDO/AIA, and IRIS. Spatially, this corresponds to a small loop visible in the SDO/AIA Fe XVIII emission, which matches a similar structure lower in the solar atmosphere seen by IRIS in SJI1330 and 1400 \u00c5. The NuSTAR emission in both 2.5\u20134 and 4\u20136 keV is located in a source at this loop location. The IRIS slit was over the microflaring loop, and fits show little change in Mg II but do show intensity increases, slight width enhancements, and redshifts in Si IV and O IV, indicating that this microflare had most significance in and above the upper chromosphere. The NuSTAR microflare spectrum is well fitted by a thermal component of 5.1 MK and 6.2 \u00d7 10^(44) cm^(\u22123), which corresponds to a thermal energy of 1.5 \u00d7 10^(26) erg, making it considerably smaller than previously studied active region microflares. No non-thermal emission was detected but this could be due to the limited effective exposure time of the observation. This observation shows that even ordinary features seen in UV can remarkably have a higher-energy component that is clear in X-rays.",
"date": "2019-08-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "881",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 109",
"id_number": "CaltechAUTHORS:20190814-073445942",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190814-073445942",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Royal Society"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab2dfa",
"primary_object": {
"basename": "1812.09214.pdf",
"url": "https://authors.library.caltech.edu/records/v3ayc-8xq09/files/1812.09214.pdf"
},
"related_objects": [
{
"basename": "Hannah_2019_ApJ_881_109.pdf",
"url": "https://authors.library.caltech.edu/records/v3ayc-8xq09/files/Hannah_2019_ApJ_881_109.pdf"
}
],
"pub_year": "2019",
"author_list": "Hannah, Iain G.; Kleint, Lucia; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nsq55-cbr24",
"eprint_id": 96507,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:17:33",
"lastmod": "2026-03-31 14:05:52",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "Hannah P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Barret-Didier",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Webb-Natalie-A",
"name": {
"family": "Webb",
"given": "Natalie A."
}
}
]
},
"title": "A broadband look at the old and new ULXs of NGC 6946",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 stars: black holes \u2013 stars: neutron \u2013 X-rays: binaries \u2013 X-rays: general",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 April 5; revised 2019 May 7; accepted 2019 May 8; published 2019 August 9. \n\nWe thank our anonymous referee for useful comments on this paper. This work was supported under NASA contract NNG08FD60C. D.J.W. acknowledges financial support from STFC in the form of an Ernest Rutherford fellowship. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This work has also made use of observations by XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. Results reported in this article are based in part on public data obtained from the Chandra and Swift data archives, and on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, XMM - , CXO - , Swift(XRT) - , HST. - \n\nSoftware: astropy (Astropy Collaboration et al. 2013, 2018), CIAO (Fruscione et al. 2006), HENDRICS (Bachetti 2015), HEASoft (NASA's High Energy Astrophysics Science Archive Research Center (HEASARC), 2014), NuSTARDAS, XMM-Newton SAS.\n\nPublished - Earnshaw_2019_ApJ_881_38.pdf
Submitted - 1905.03383.pdf
",
"abstract": "Two recent observations of the nearby galaxy NGC 6946 with NuSTAR, one simultaneous with an XMM-Newton observation, provide an opportunity to examine its population of bright accreting sources from a broadband perspective. We study the three known ultraluminous X-ray sources (ULXs) in the galaxy, and find that ULX-1 and ULX-2 have very steep power-law spectra with \u0393=3.6^(+0.4)_(\u22120.3) in both cases. Their properties are consistent with being super-Eddington accreting sources with the majority of their hard emission obscured and down-scattered. ULX-3 (NGC 6946 X-1) is significantly detected by both XMM-Newton and NuSTAR at L_X = (6.5 \u00b1 0.1) \u00d7 10^(39) erg s^(\u22121), and has a power-law spectrum with \u0393 = 2.51 \u00b1 0.05. We are unable to identify a high-energy break in its spectrum like that found in other ULXs, but the soft spectrum likely hinders our ability to detect one. We also characterize the new source, ULX-4, which is only detected in the joint XMM-Newton and NuSTAR observation, at L X = (2.27 \u00b1 0.07) \u00d7 10^(39) erg s^(\u22121), and is absent in a Chandra observation 10 days later. It has a very hard cutoff power-law spectrum with \u0393 = 0.7 \u00b1 0.1 and E_(cut)=11^(+9)_(\u22124) keV. We do not detect pulsations from ULX-4, but its transient nature can be explained either as a neutron star ULX briefly leaving the propeller regime or as a micro-tidal disruption event induced by a stellar-mass compact object.",
"date": "2019-08-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "881",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 38",
"id_number": "CaltechAUTHORS:20190618-153955252",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190618-153955252",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
},
{
"agency": "NASA",
"grant_number": "NAS 5-26555"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab20cd",
"primary_object": {
"basename": "1905.03383.pdf",
"url": "https://authors.library.caltech.edu/records/nsq55-cbr24/files/1905.03383.pdf"
},
"related_objects": [
{
"basename": "Earnshaw_2019_ApJ_881_38.pdf",
"url": "https://authors.library.caltech.edu/records/nsq55-cbr24/files/Earnshaw_2019_ApJ_881_38.pdf"
}
],
"pub_year": "2019",
"author_list": "Earnshaw, Hannah P.; Grefenstette, Brian W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dr10m-m0362",
"eprint_id": 96446,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:11:39",
"lastmod": "2026-03-31 16:13:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Repetto-S",
"name": {
"family": "Repetto",
"given": "S."
},
"orcid": "0000-0001-5029-0059"
},
{
"id": "Wevers-T",
"name": {
"family": "Wevers",
"given": "T."
}
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Hynes-R-I",
"name": {
"family": "Hynes",
"given": "R. I."
}
},
{
"id": "Nelemans-G",
"name": {
"family": "Nelemans",
"given": "G."
}
},
{
"id": "Kostrzewa-Rutkowska-Z",
"name": {
"family": "Kostrzewa-Rutkowska",
"given": "Z."
}
},
{
"id": "Wyrzykowski-L",
"name": {
"family": "Wyrzykowski",
"given": "L."
}
},
{
"id": "Britt-C-T",
"name": {
"family": "Britt",
"given": "C. T."
}
},
{
"id": "Heinke-C-O",
"name": {
"family": "Heinke",
"given": "C. O."
},
"orcid": "0000-0003-3944-6109"
},
{
"id": "Casares-J",
"name": {
"family": "Casares",
"given": "J."
}
},
{
"id": "Johnson-C-B",
"name": {
"family": "Johnson",
"given": "C. B."
}
},
{
"id": "Maccarone-T-J",
"name": {
"family": "Maccarone",
"given": "T. J."
},
"orcid": "0000-0003-0976-4755"
},
{
"id": "Steeghs-D-T-H",
"name": {
"family": "Steeghs",
"given": "D. T. H."
}
}
]
},
"title": "Constraining the nature of the accreting binary in CXOGBS J174623.5\u2212310550",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "binaries: close, stars: individual: CXOGBS J174623.5\u2212310550, X-rays: binaries",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nAccepted 2019 May 16. Received 2019 April 23; in original form 2018 November 5. Published: 05 June 2019.\n\nBased on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 088.D-0096(A) and 095.D-0973(A). This research has used the SIMBAD data base, operated at CDS, Strasbourg, France, and of the NASA's Astrophysics Data System. IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. Tom Marsh is thanked for developing and sharing his package MOLLY. We thank the anonymous referee for constructive comments. MAPT and JC acknowledge support by the Spanish Ministry of Economy, Industry, and Competitiveness (MINECO) under grant AYA2017-83216-P. MAPT also acknowledges support via a Ram\u00f3n y Cajal Fellowship (RYC-2015-17854). The work of SR was supported by the Netherlands Research School for Astronomy (NOVA). PGJ and ZKR acknowledge support from European Research Council Consolidator grant 647208. RIH and CBJ acknowledge support from NASA through Chandra Award Number AR3-14002X issued by the Chandra X-ray Observatory Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. The work of LW has been supported by the Polish National Science Centre grant no.DEC-2011/03/B/ST9/02573. The OGLE project has received funding from the National Science Centre, Poland, grant MAESTRO 2014/14/A/ST9/00121 and 2015/18/M/ST9/00544 to Andrzej Udalski. COH is supported by NSERC Discovery grant RGPIN-2016-04602, and a Discovery Accelerator Supplement. SR is thankful to Hagai Perets for his insights on the triple scenario.\n\nPublished - stz1405.pdf
Accepted Version - 1905.08107.pdf
",
"abstract": "We report optical and infrared observations of the X-ray source CXOGBS J174623.5\u2212310550. This Galactic object was identified as a potential quiescent low-mass X-ray binary accreting from an M-type donor on the basis of optical spectroscopy and the broad H\u2009\u03b1 emission line. The analysis of X-shooter spectroscopy covering three consecutive nights supports an M2/3-type spectral classification. Neither radial velocity variations nor rotational broadening is detected in the photospheric lines. No periodic variability is found in I- and r\u2032-band light curves. We derive r\u2032 = 20.8, I = 19.2, and K_s \u2248 16.6 for the optical and infrared counterparts with the M-type star contributing \u224890 per cent to the I-band light. We estimate its distance to be 1.3\u20131.8 kpc. The lack of radial velocity variations implies that the M-type star is not the donor star in the X-ray binary. This could be an interloper or the outer body in a hierarchical triple. We constrain the accreting binary to be a \u22722.2 h orbital period eclipsing cataclysmic variable or a low-mass X-ray binary lying in the foreground of the Galactic bulge.",
"date": "2019-08-01",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "487",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2296-2306",
"id_number": "CaltechAUTHORS:20190614-111556752",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190614-111556752",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2017-83216-P"
},
{
"agency": "Ram\u00f3n y Cajal Programme",
"grant_number": "RYC-2015-17854"
},
{
"agency": "Nederlandse Onderzoekschool Voor Astronomie (NOVA)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "NASA",
"grant_number": "AR3-14002X"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "DEC-2011/03/B/ST9/02573"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2014/14/A/ST9/00121"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2015/18/M/ST9/00544"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)",
"grant_number": "RGPIN-2016-04602"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stz1405",
"primary_object": {
"basename": "1905.08107.pdf",
"url": "https://authors.library.caltech.edu/records/dr10m-m0362/files/1905.08107.pdf"
},
"related_objects": [
{
"basename": "stz1405.pdf",
"url": "https://authors.library.caltech.edu/records/dr10m-m0362/files/stz1405.pdf"
}
],
"pub_year": "2019",
"author_list": "Torres, M. A. P.; Repetto, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3wgyr-pb932",
"eprint_id": 97760,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:02:28",
"lastmod": "2026-03-31 00:11:27",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Irrgang-A",
"name": {
"family": "Irrgang",
"given": "A."
},
"orcid": "0000-0002-0465-3725"
},
{
"id": "Geier-S",
"name": {
"family": "Geier",
"given": "S."
},
"orcid": "0000-0002-3948-9339"
},
{
"id": "Heber-U",
"name": {
"family": "Heber",
"given": "U."
},
"orcid": "0000-0001-7798-6769"
},
{
"id": "Kupfer-T",
"name": {
"family": "Kupfer",
"given": "T."
},
"orcid": "0000-0002-6540-1484"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
}
]
},
"title": "PG 1610+062: a runaway B star challenging classical ejection mechanisms",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: abundances \u2013 stars: individual: HD137366 \u2013 stars: kinematics and dynamics \u2013 stars: individual: PG 1610+062 \u2013 stars: early-type",
"note": "\u00a9 2019 ESO. Article published by EDP Sciences. \n\nReceived 7 March 2019; Accepted 10 July 2019; Published online 06 August 2019. \n\nWe thank John E. Davis for the development of the SLXFIG module used to prepare the figures in this paper. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 091.C-0713(A). Based on data from the CAHA Archive at CAB (INTA-CSIC). Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. The SDSS web site is www.sdss.org. SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration including the Brazilian Participation Group, the Carnegie Institution for Science, Carnegie Mellon University, the Chilean Participation Group, the French Participation Group, Harvard-Smithsonian Center for Astrophysics, Instituto de Astrof\u00edsica de Canarias, The Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe (IPMU)/University of Tokyo, Lawrence Berkeley National Laboratory, Leibniz Institut f\u00fcr Astrophysik Potsdam (AIP), Max-Planck-Institut f\u00fcr Astronomie (MPIA Heidelberg), Max-Planck-Institut f\u00fcr Astrophysik (MPA Garching), Max-Planck-Institut f\u00fcr Extraterrestrische Physik (MPE), National Astronomical Observatories of China, New Mexico State University, New York University, University of Notre Dame, Observat\u00f3rio Nacional/MCTI, The Ohio State University, Pennsylvania State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, Universidad Nacional Aut\u00f3noma de M\u00e9xico, University of Arizona, University of Colorado Boulder, University of Oxford, University of Portsmouth, University of Utah, University of Virginia, University of Washington, University of Wisconsin, Vanderbilt University, and Yale University. Based on observations made with the NASA Galaxy Evolution Explorer. GALEX is operated for NASA by the California Institute of Technology under NASA contract NAS5-98034. The Pan-STARRS1 Surveys (PS1) and the PS1 public science archive have been made possible through contributions by the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, the Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under Grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation Grant No. AST-1238877, the University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos National Laboratory, and the Gordon and Betty Moore Foundation. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration.\n\nPublished - aa35429-19.pdf
Accepted Version - 1907.06375.pdf
",
"abstract": "Hypervelocity stars are rare objects, mostly main-sequence (MS) B stars, traveling so fast that they will eventually escape from the Milky Way. Recently, it has been shown that the popular Hills mechanism, in which a binary system is disrupted via a close encounter with the supermassive black hole at the Galactic center, may not be their only ejection mechanism. The analyses of Gaia data ruled out a Galactic center origin for some of them, and instead indicated that they are extreme disk runaway stars ejected at velocities exceeding the predicted limits of classical scenarios (dynamical ejection from star clusters or binary supernova ejection). We present the discovery of a new extreme disk runaway star, PG 1610+062, which is a slowly pulsating B star bright enough to be studied in detail. A quantitative analysis of spectra taken with ESI at the Keck Observatory revealed that PG 1610+062 is a late B-type MS star of 4\u20135 M\u2299with low projected rotational velocity. Abundances (C, N, O, Ne, Mg, Al, Si, S, Ar, and Fe) were derived differentially with respect to the normal B star HD 137366 and indicate that PG 1610+062 is somewhat metal rich. A kinematic analysis, based on our spectrophotometric distance (17.3 kpc) and on proper motions from Gaia's second data release, shows that PG 1610+062 was probably ejected from the Carina-Sagittarius spiral arm at a velocity of 550 \u00b1 40 km s^(\u22121), which is beyond the classical limits. Accordingly, the star is in the top five of the most extreme MS disk runaway stars and is only the second among the five for which the chemical composition is known.",
"date": "2019-08",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "628",
"publisher": "EDP Sciences",
"pagerange": "Art. No. L5",
"id_number": "CaltechAUTHORS:20190812-094248032",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190812-094248032",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "Gaia Multilateral Agreement"
},
{
"agency": "Alfred P. Sloan Foundation"
},
{
"agency": "Department of Energy (DOE)"
},
{
"agency": "Participating Institutions"
},
{
"agency": "NASA",
"grant_number": "NAS5-98034"
},
{
"agency": "NASA",
"grant_number": "NNX08AR22G"
},
{
"agency": "NSF",
"grant_number": "AST-1238877"
},
{
"agency": "Gordon and Betty Moore Foundation"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/201935429",
"primary_object": {
"basename": "aa35429-19.pdf",
"url": "https://authors.library.caltech.edu/records/3wgyr-pb932/files/aa35429-19.pdf"
},
"related_objects": [
{
"basename": "1907.06375.pdf",
"url": "https://authors.library.caltech.edu/records/3wgyr-pb932/files/1907.06375.pdf"
}
],
"pub_year": "2019",
"author_list": "Irrgang, A.; Geier, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gntgc-q8p32",
"eprint_id": 97935,
"eprint_status": "archive",
"datestamp": "2023-08-19 17:06:11",
"lastmod": "2026-03-31 14:02:40",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Bharali-P",
"name": {
"family": "Bharali",
"given": "Priya"
}
},
{
"id": "Chandra-S",
"name": {
"family": "Chandra",
"given": "Sunil"
},
"orcid": "0000-0002-8776-1835"
},
{
"id": "Chauhan-J",
"name": {
"family": "Chauhan",
"given": "Jaiverdhan"
},
"orcid": "0000-0003-0330-1901"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Roy-J",
"name": {
"family": "Roy",
"given": "Jayashree"
},
"orcid": "0000-0002-2329-5863"
},
{
"id": "Boettcher-M",
"name": {
"family": "Boettcher",
"given": "Markus"
}
},
{
"id": "Boruah-K",
"name": {
"family": "Boruah",
"given": "Kalyanee"
}
}
]
},
"title": "Re-awakening of GRS 1716\u2013249 after 23\u00a0yr, observed by Swift/XRT and NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013 black hole physics \u2013X-rays: binaries \u2013 X-rays: individual: GRS 1716\u2013249",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 May 28. Received 2019 May 28; in original form 2017 July 18. Published: 04 June 2019. \n\nThis research has made use of the software and/or data obtained through the High Energy Astrophysics Science Archive Research Center (HEASARC) online service, provided by the NASA/Goddard Space Flight Center and the SWIFT data center. We thank NuSTAR team for making NuSTAR data public. MAXI data are obtained from MAXI team, RIKEN, JAXA. The authors gratefully acknowledge the anonymous referee for constructive comments that improved the paper. The authors are also thankful to PI's for proposing these observations. JC and SC are also grateful to Prof. H. M. Antia, Prof. A. R. Rao, and Prof. S. Bhattacharyya for constructive discussions about diagnostics and interpretations. The work by MB is supported by the Department of Science and Technology and National Research Foundation (NRF) of South Africa through the South African Research Chairs Initiative (SARChI), grant no. 64789. SC acknowledges the supports by CSR-NWU and NRF.\n\nPublished - stz1492.pdf
Accepted Version - 1905.12657.pdf
",
"abstract": "In this work, we present a spectral and temporal analysis of Swift/XRT and NuSTAR observations of GRS 1716\u2013249 during its recent 2016\u20132017 outburst. This low-mass X-ray binary underwent an extraordinary outburst after a long quiescence of 23 yr, since its last major outburst in 1993. The source was observed over two different epochs during 2017 April 7 and 10. The best-fitting joint spectral fitting in the energy range 0.5\u201379.0 keV indicates that the spectrum is best described by relatively cold, weak disc blackbody emission, dominant thermal Comptonization emission, and a relativistically broadened fluorescent iron K \u03b1 emission line. We observed a clear indication of a Compton hump around 30 keV. We also detected an excess feature of 1.3 keV. Assuming a lamp-post geometry of the corona, we constrained the inner disc radius for both observations to 11.92^(+8.62)_(\u221211.92) R_(ISCO) (i.e. an upper limit) and 10.39^(+9.51)_(\u22123.02) R_(ISCO)(where R_(ISCO) \u2261 radius of the innermost stable circular orbit) for the first epoch (E1) and second epoch (E2), respectively. A significant (5\u03c3) type C quasi-periodic oscillation (QPO) at 1.20 \u00b1 0.04 Hz is detected for the first time for GRS 1716\u2013249, which drifts to 1.55 \u00b1 0.04 Hz (6\u03c3) at the end of the second observation. The derived spectral and temporal properties show a positive correlation between the QPO frequency and the photon index.",
"date": "2019-08",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "487",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3150-3161",
"id_number": "CaltechAUTHORS:20190816-075233072",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190816-075233072",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Department of Science and Technology (South Africa)"
},
{
"agency": "National Research Foundation (South Africa)"
},
{
"agency": "South African Research Chairs Initiative (SARChI)",
"grant_number": "64789"
},
{
"agency": "North-West University Potchefstroom"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stz1492",
"primary_object": {
"basename": "1905.12657.pdf",
"url": "https://authors.library.caltech.edu/records/gntgc-q8p32/files/1905.12657.pdf"
},
"related_objects": [
{
"basename": "stz1492.pdf",
"url": "https://authors.library.caltech.edu/records/gntgc-q8p32/files/stz1492.pdf"
}
],
"pub_year": "2019",
"author_list": "Bharali, Priya; Chandra, Sunil; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3cqeg-yq742",
"eprint_id": 96517,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:43:45",
"lastmod": "2026-03-31 05:49:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "Poshak"
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "Jon M."
}
},
{
"id": "Uttley-P",
"name": {
"family": "Uttley",
"given": "Phil"
}
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Broadband X-ray Spectral and Timing Analyses of the Black Hole Binary Candidate Swift J1658.2-4242: Rapid Flux Variation and the Turn-on of a Transient QPO",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 X-rays: binaries \u2013 X-rays: individual (Swift J1658.2-4242)",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 February 27; revised 2019 May 1; accepted 2019 May 23; published 2019 July 10. \n\nWe thank the anonymous referee for the helpful comments that improved the paper. We thank Tom Russell and James Miller-Jones for providing information about ATCA radio observations. D.J.W. acknowledges support from the STFC Ernest Rutherford Fellowship. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR operations, software, and calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has also made use of data obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States, and Swift, a NASA mission with participation of the Italian Space Agency (ASI) and the Particle Physics and Astronomy Research Council in the United Kingdom.\n\nPublished - Xu_2019_ApJ_879_93.pdf
Submitted - 1905.10909.pdf
",
"abstract": "We report results from joint Nuclear Spectroscopic Telescope Array, Swift, and XMM-Newton observations of the newly discovered black hole X-ray binary candidate Swift J1658.2\u20134242 in the intermediate state. We observe a peculiar event in this source, with its X-ray flux rapidly decreasing by ~45% in ~40 s, accompanied by only subtle changes in the shape of the broadband X-ray spectrum. In addition, we find a sudden turn-on of a transient quasi-periodic oscillation (QPO) with a frequency of 6\u20137 Hz around the time of the flux change, and the total fractional rms amplitude of the power spectrum increases from ~2% to ~10%. The X-ray spectral and timing analyses indicate that the flux decrease is driven by intrinsic changes in the accretion flow around the black hole, rather than intervening material along the line of sight. In addition, we do not significantly detect any relativistic disk reflection component, indicating it is much weaker than previously observed while the source was in the bright hard state. We propose accretion disk instabilities triggered at a large disk radius as the origin of the fast transition in spectral and timing properties, and discuss possible causes of the unusual properties observed in Swift J1658.2\u20134242. The prompt flux variation detected along with the emergence of a QPO makes the event an interesting case for investigating QPO mechanisms in black hole X-ray binaries.",
"date": "2019-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "879",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 93",
"id_number": "CaltechAUTHORS:20190619-085644567",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190619-085644567",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab24bf",
"primary_object": {
"basename": "1905.10909.pdf",
"url": "https://authors.library.caltech.edu/records/3cqeg-yq742/files/1905.10909.pdf"
},
"related_objects": [
{
"basename": "Xu_2019_ApJ_879_93.pdf",
"url": "https://authors.library.caltech.edu/records/3cqeg-yq742/files/Xu_2019_ApJ_879_93.pdf"
}
],
"pub_year": "2019",
"author_list": "Xu, Yanjun; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/cx7sq-wc626",
"eprint_id": 98059,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:35:11",
"lastmod": "2026-03-18 04:49:23",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "von-Rosenvinge-T-T",
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "27-Day Modulation of Cosmic Ray Intensities During the Last Two Solar Minima",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nPre-published on: 2019 July 22. \n\nThis work was supported by NASA under grant 80NSSC18K0223. We thank the ACE/SWEPAM and MAG instrument teams and the ACE Science Center (http://www.srl.caltech.edu/ACE/ASC) for making their solar wind and magnetic field data publicly available. We acknowledge the NMDB database (www.nmdb.eu), founded under the European Union's FP7 program (contract 213007) for hosting and distributing the Newark neutron monitor data from the Bartol Research Institute, supported by the NSF under grants ANT-0739620 and ANT-0838839. We thank Todd Hoeksema and the Wilcox Solar Observatory (http://wso.stanford.edu) for providing the HCS and coronal field map data.\n\nPublished - ICRC2019_1105.pdf
",
"abstract": "Variations in both anomalous cosmic ray (ACR) and galactic cosmic ray (GCR) intensities at the solar rotation period (\u223c27 days) are often observed, and appear throughout much of 2016 into 2019 during the present A>0 polarity solar minimum. During the previous A<0 solar minimum, such variations were evident at energies from a few MeV to many GeV from mid-2007 through late 2008, and were much larger for ACRs than for GCRs at comparable energy. The particle intensities had an inverse power-law correlation with the solar wind speed, intensity peaks occurred only near alternate crossings of the heliospheric current sheet, and the variations in amplitudes were larger than typical for an A<0 epoch. The heliospheric environment was unusual compared with earlier cycles, with lower solar wind dynamic pressure, weaker interplanetary magnetic field strength, and record-setting GCR intensities. The present high-energy GCR intensities are higher than ever before reported in an A>0 cycle (although lower than in several A<0 cycles), indicating that unusual modulation conditions still prevail. \nUsing high statistical precision measurements from the ACE spacecraft along with neutron monitor data, we present observations of the 27-day intensity variations in both ACRs and GCRs during the last two solar minima and describe how they depend on particle energy, rigidity, and spectrum, and on interplanetary conditions such as solar wind speed, magnetic field strength, andmcurrent sheet tilt. We compare the variations observed in this cycle with those in the previous opposite polarity cycle and discuss implications for particle transport in the heliosphere.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190821-075835551",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190821-075835551",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC18K0223"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "213007"
},
{
"agency": "NSF",
"grant_number": "ANT-0739620"
},
{
"agency": "NSF",
"grant_number": "ANT-0838839"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"primary_object": {
"basename": "ICRC2019_1105.pdf",
"url": "https://authors.library.caltech.edu/records/cx7sq-wc626/files/ICRC2019_1105.pdf"
},
"pub_year": "2019",
"author_list": "Leske, R. A.; Cummings, A. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/y2zab-jyc23",
"eprint_id": 97479,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:33:24",
"lastmod": "2026-03-18 04:49:25",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Binns-W-R",
"name": {
"family": "Binns",
"given": "W. R."
},
"orcid": "0000-0001-6110-3407"
},
{
"id": "Israel-M-H",
"name": {
"family": "Israel",
"given": "M. H."
},
"orcid": "0000-0002-8104-208X"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "de-Nolfo-G-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "von-Rosenvinge-T-T",
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
}
]
},
"title": "Elemental Source Composition Measurements and the Origin of Galactic Cosmic Rays",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nPre-published on: 2019 July 22. \n\nThis research is supported by NASA under Grant #80NSSC18K0223.\n\nPublished - pdf
",
"abstract": "We present measurements of the elemental abundances of ultra-heavy (Z>29) cosmic rays made by the CRIS instrument on NASA's ACE satellite. The data set corresponds to 7406 days of data collection from December 4, 1997 through Feb. 18, 2019. We detected a total of 1205 ultra-heavy nuclei in the charge range of Z=30-40. The charge resolution that we obtain shows essentially complete separation of the elements over this charge range. We derive preliminary source abundances from these measurements. These source abundances show that the ordering of refractory and volatile elements with atomic mass is greatly improved when compared to a mix of massive star outflow plus SN ejecta with normal ISM, rather than with only normal ISM. Additionally, in this ordering the refractory and volatile elements have similar slopes and refractory elements are preferentially accelerated by a factor of ~4. The measured abundances support a model in which cosmic ray source material is a mix of massive star outflow plus supernova ejecta and normal ISM, consistent with conclusions reached from the SuperTIGER high-altitude balloon measurements.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190729-091757335",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190729-091757335",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC18K0223"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"primary_object": {
"basename": "pdf",
"url": "https://authors.library.caltech.edu/records/y2zab-jyc23/files/pdf"
},
"pub_year": "2019",
"author_list": "Binns, W. R.; Israel, M. H.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/h97fs-baa58",
"eprint_id": 98057,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:35:06",
"lastmod": "2026-03-18 04:49:49",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Binns-W-R",
"name": {
"family": "Binns",
"given": "W. R."
},
"orcid": "0000-0001-6110-3407"
},
{
"id": "Rose-R-G",
"name": {
"family": "Rose",
"given": "R. G."
}
},
{
"id": "Brandt-T-J",
"name": {
"family": "Brandt",
"given": "T. J."
},
"orcid": "0000-0003-4087-1786"
},
{
"id": "Dowkontt-P-F",
"name": {
"family": "Dowkontt",
"given": "P. F."
}
},
{
"id": "Hams-T",
"name": {
"family": "Hams",
"given": "T."
}
},
{
"id": "Israel-M-H",
"name": {
"family": "Israel",
"given": "M. H."
},
"orcid": "0000-0002-8104-208X"
},
{
"id": "Link-J-T",
"name": {
"family": "Link",
"given": "J. T."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Mitchell-J-W",
"name": {
"family": "Mitchell",
"given": "J. W."
}
},
{
"id": "Murphy-R-P",
"name": {
"family": "Murphy",
"given": "R. P."
}
},
{
"id": "Rauch-B-F",
"name": {
"family": "Rauch",
"given": "B. F."
}
},
{
"id": "Sakai-Kenichi",
"name": {
"family": "Sakai",
"given": "K."
}
},
{
"id": "Sasaki-Makoto",
"name": {
"family": "Sasaki",
"given": "M."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Waddington-C-J",
"name": {
"family": "Waddington",
"given": "C. J."
}
},
{
"id": "Walsh-N-E",
"name": {
"family": "Walsh",
"given": "N. E."
}
},
{
"id": "Ward-J-E",
"name": {
"family": "Ward",
"given": "J. E."
}
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Galactic Cosmic Ray Energy Spectra for Heavy Elements (Ne to Zn) from \u223c0.8 to \u223c10 GeV/nuc with the SuperTIGER Instrument",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nPre-published on: 2019 July 22. \n\nThis work was supported by NASA under grants NNX09AC17G, NNX09AC18G, NNX14AB24G, NNX14AB25G, and NNX15AC15G, by the Peggy and Steve Fossett Foundation, and by the McDonnell Center for the Space Sciences at Washington University in St. Louis. We thank the ACE/CRIS instrument team and the ACE Science Center for providing ACE data.\n\nPublished - ICRC2019_095.pdf
",
"abstract": "SuperTIGER (Trans-Iron Galactic Element Recorder) is a large-area balloon-borne instrument built to measure the galactic cosmic-ray (GCR) abundances of elements from Z=10 (Ne) through Z=56 (Ba) at energies from ~0.8 to ~10 GeV/nuc. SuperTIGER flew over Antarctica for a record-breaking 55 days, from December 8, 2012 to February 1, 2013. We will report progress on calculations of galactic cosmic ray spectra corrected to the top of the atmosphere for abundant elements between Ne and Zn from the SuperTIGER flight data. The energy spectra calculations will include up to date refinements to the energy calibrations for the acrylic and aerogel Cherenkov detectors in the instrument, and we will report on new instrument and atmospheric corrections to the top of the atmosphere for energies and abundances. \n\nHeinz and Sunyaev (2002) suggested that microquasar jets like those observed in GRS 1915+105 and GRO J1655-40 may be observable as near monoenergetic peaks in heavy ion spectra in the 3-10 GeV/nuc energy range. The large area and long flight duration of SuperTIGER is particularly suited to looking for these microquasar signatures with good statistics. We will compare our SuperTIGER spectra with ACE/CRIS and HEAO-3 spectra and with model GCR spectra solar modulated for the time period of the flight, and we will search for features that may be produced by microquasar jets.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190821-073116292",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190821-073116292",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX09AC17G"
},
{
"agency": "NASA",
"grant_number": "NNX09AC18G"
},
{
"agency": "NASA",
"grant_number": "NNX14AB24G"
},
{
"agency": "NASA",
"grant_number": "NNX14AB25G"
},
{
"agency": "NASA",
"grant_number": "NNX15AC15G"
},
{
"agency": "Peggy and Steve Fossett Foundation"
},
{
"agency": "Washington University"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"primary_object": {
"basename": "ICRC2019_095.pdf",
"url": "https://authors.library.caltech.edu/records/h97fs-baa58/files/ICRC2019_095.pdf"
},
"pub_year": "2019",
"author_list": "Labrador, A. W.; Binns, W. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ngg8b-j8919",
"eprint_id": 98063,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:35:29",
"lastmod": "2024-01-14 21:52:49",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Krizmanic-J-F",
"name": {
"family": "Krizmanic",
"given": "John F."
}
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "Allan W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "Richard A."
},
"orcid": "0000-0003-2178-9111"
}
]
},
"title": "HNX/SuperTIGER Silicon Strip Detector Response to Nuclei in Lead Primary and Fragmented Test Beams",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.\n\nPre-published on: 2019 July 22. \n\nWe thank Mark Wiedenbeck (CalTech/SRL/JPL) for the use of the silicon calibration detectors, the Rel-Labs preamplifier electronics, and the Canberra shaping amplifiers used in this beam test. We also thank Marco Ricci (INFN/Frascati) for help in obtaining electronics and supplies from the CERN electronics pool. Finally, we thank CERN for the opportunity to perform this beam test and providing exceptional particle beams.\n\nPublished - ICRC2019_094.pdf
",
"abstract": "The response to 150 GeV/nuc primary lead (^(208)Pb) and fragmented (A/Z=2.4, 2.2, 2.0) beams measured a silicon strip detector, designed for use in the Heavy Nuclei eXplorer (HNX) and an upgrade of the Super Trans-Iron Galactic Element Recorder (SuperTIGER) balloon experiment, was evaluated in a CERN test beam (H8A) during Nov - Dec 2018. The 500 \u03bcm thick, single-sided silicon detectors have 32 DC-coupled strips with 3 mm pitch on the junction side with 9.6\u00d79.6 cm^2 active area. Discrete charge-preamplifiers and shaping amplifiers were used to read out the ohmic and junction side signals simultaneously using the SuperTIGER DAQ system. We report on the response in a configuration where all 32 strips were joined and read out together. The strip detector-under-test was situated \nbetween planar silicon detectors, which provided the charge selection as well as a comparison of the measured response of each detector. The combined data set shows excellent charge resolution and finely resolved elemental peaks from helium (Z=2) through lead (Z=82). In this paper, we provide a description of the test beam experiment and the results of the charge resolution analysis.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190821-083554328",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190821-083554328",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"primary_object": {
"basename": "ICRC2019_094.pdf",
"url": "https://authors.library.caltech.edu/records/ngg8b-j8919/files/ICRC2019_094.pdf"
},
"pub_year": "2019",
"author_list": "Krizmanic, John F.; Labrador, Allan W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/cr3kn-9tt37",
"eprint_id": 98061,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:35:19",
"lastmod": "2026-03-18 04:44:08",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walsh-N-E",
"name": {
"family": "Walsh",
"given": "N. E."
}
},
{
"id": "Binns-W-R",
"name": {
"family": "Binns",
"given": "W. R."
},
"orcid": "0000-0001-6110-3407"
},
{
"id": "Israel-M-H",
"name": {
"family": "Israel",
"given": "M. H."
},
"orcid": "0000-0002-8104-208X"
},
{
"id": "Murphy-R-P",
"name": {
"family": "Murphy",
"given": "R. P."
}
},
{
"id": "Rauch-B-F",
"name": {
"family": "Rauch",
"given": "B. F."
}
},
{
"id": "Ward-J-E",
"name": {
"family": "Ward",
"given": "J. E."
}
},
{
"id": "Brandt-T-J",
"name": {
"family": "Brandt",
"given": "T. J."
},
"orcid": "0000-0003-4087-1786"
},
{
"id": "Link-J-T",
"name": {
"family": "Link",
"given": "J. T."
}
},
{
"id": "Mitchell-J-W",
"name": {
"family": "Mitchell",
"given": "J. W."
}
},
{
"id": "Hams-T",
"name": {
"family": "Hams",
"given": "T."
}
},
{
"id": "Sakai-Kenichi",
"name": {
"family": "Sakai",
"given": "K."
}
},
{
"id": "Sasaki-Makoto",
"name": {
"family": "Sasaki",
"given": "M."
}
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Waddington-C-J",
"name": {
"family": "Waddington",
"given": "C. J."
}
}
]
},
"title": "SuperTIGER Abundances of Galactic Cosmic-Rays for the Charge Interval Z=41-56",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nPre-published on: 2019 July 22.\n\nPublished - ICRC2019_147.pdf
",
"abstract": "On December 8, 2012 the SuperTIGER (Super Trans-Iron Galactic Element Recorder) instrument was launched from Williams Field, Antarctica on a long-duration balloon flight that lasted 55 days and maintained a mean altitude of 125,000 feet. SuperTIGER measured the relative abundances of Galactic cosmic-ray nuclei with high statistical precision and well resolved individual element peaks from Neon to Zirconium (charges Z=10-40). SuperTIGER also made exploratory measurements of the relative abundances up to Barium (Z=56). Although the statistics are low for elements heavier than Zirconium, we will show how the relative abundances of charges Z=41-56 compare to those reported by HEAO3-HNE during 1979-81. The relative abundances of elements Zirconium through Neodymium (Z=60) are of particular interest because they are likely formed both by supernova explosions and by binary neutron star mergers. A well resolved measurement of this range of elements can constrain the contributions to the Galactic cosmic-ray composition from both of these possible sources.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190821-081636867",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190821-081636867",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"primary_object": {
"basename": "ICRC2019_147.pdf",
"url": "https://authors.library.caltech.edu/records/cr3kn-9tt37/files/ICRC2019_147.pdf"
},
"pub_year": "2019",
"author_list": "Walsh, N. E.; Binns, W. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/53tha-mfx51",
"eprint_id": 98062,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:35:24",
"lastmod": "2024-01-14 21:52:47",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rauch-B-F",
"name": {
"family": "Rauch",
"given": "B. F."
}
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
}
]
},
"title": "SuperTIGER-2 2018 Flight Payload Recovery and Preliminary Instrument Assessment",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nPre-published on: 2019 July 22. \n\nThis work was supported by NASA Grant #NNX15AC23G, the Peggy and Steve Fossett Foundation and the McDonnell Center for the Space Sciences. \n\nWe thank the NASA Columbia Scientific Balloon Facility (CSBF), the NASA Balloon Program Office, and the NSF United States Antarctic Program for the excellent and highly professional efforts that resulted in the record long-duration balloon flight for SuperTIGER and the successful recovery efforts for SuperTIGER and SuperTIGER-2. We also wish to thank Raven Aerostar, the manufacturer of the amazing balloon-craft we rely on for our science, as well as the Antarctic Support Contract (ASC) Team. Finally, we are particularly appreciative of the efforts of Scott Battaion (NASA/CSBF) and Kaija Webster (ASC) that made the recovery of SuperTIGER-2 and planned subsequent flight possible.\n\nPublished - ICRC2019_131.pdf
",
"abstract": "The SuperTIGER (Trans-Iron Galactic Element Recorder) experiment was launched for the second time from the Long Duration Balloon (LDB) site near McMurdo Station, Antarctica on December 20, 2018 at 1:36 AM NZDT. The balloon reached a peak altitude of \u223c79,300 ft before it began to descend, and the flight had to be terminated after just over six hours aloft. The payload landed at 8:17 AM NZDT approximately 150 miles from McMurdo Station at 75.80 S and 161.68 E. Satellite imagery of the site revealed that it was in a crevasse field, but a Twin Otter reconnaissance flight showed none in the immediate vicinity. A subsequent site survey by a team flown in by helicopter with ground penetrating radar was able to flag a safe zone including helicopter landing sites. The SuperTIGER-2 payload was recovered in two days with two Bell 212 helicopters followed by one day with a Basler, which involved transferring the payload to a safe fixed wing landing site roughly two miles away in three helicopter sling loads. After return to the LDB site the instrument modules were reassembled, rewired and tested prior to their being shipped north. The instrument was found to be in overall good condition, with all testable electronics channels working, and minimal mechanical damage. SuperTIGER-2 could be refurbished to fly again as early as this next Antarctic season.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190821-082409473",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190821-082409473",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX15AC23G"
},
{
"agency": "Peggy and Steve Fossett Foundation"
},
{
"agency": "McDonnell Center for the Space Sciences"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"primary_object": {
"basename": "ICRC2019_131.pdf",
"url": "https://authors.library.caltech.edu/records/53tha-mfx51/files/ICRC2019_131.pdf"
},
"pub_year": "2019",
"author_list": "Rauch, B. F.; Labrador, A. W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/eg4ca-pqa21",
"eprint_id": 98060,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:35:15",
"lastmod": "2024-01-14 21:52:44",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "B. C."
}
},
{
"id": "Lai-N",
"name": {
"family": "Lai",
"given": "N."
}
},
{
"id": "Richardson-J-D",
"name": {
"family": "Richardson",
"given": "J. D."
},
"orcid": "0000-0003-4041-7540"
}
]
},
"title": "Voyager 2 Observations of the Anisotropy of Anomalous Cosmic Rays in the Heliosheath",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2019 owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nPre-published on: 2019 July 22. \n\nVoyager data analysis is supported by NASA Grant NNN12AA01C.\n\nPublished - ICRC2019_1071.pdf
",
"abstract": "We have analyzed data collected from the Cosmic Ray Subsystem (CRS) instrument (Stone et al., 1977) on the Voyager 2 (V2) spacecraft during calibration manuevers for the magnetic field instrument while the spacecraft was located in the inner heliosheath of the heliosphere. We find that there is a diffusive anisotropy in the intensity of \u223c0.5-35 MeV particles (mostly protons) that indicates that there exists a diffusive flow of these particles from the flank or tail of the heliosphere towards the nose and is slightly equatorward as well. This work supports the conclusion of an earlier, similar, but more restricted study (Stone et al., 2017) that the acceleration site of anomalous cosmic rays is back along the flank or tail of the solar wind termination shock.",
"date": "2019-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20190821-080755739",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190821-080755739",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"primary_object": {
"basename": "ICRC2019_1071.pdf",
"url": "https://authors.library.caltech.edu/records/eg4ca-pqa21/files/ICRC2019_1071.pdf"
},
"pub_year": "2019",
"author_list": "Cummings, A. C.; Stone, E. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z3kwe-azj32",
"eprint_id": 96270,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:19:04",
"lastmod": "2026-03-31 05:51:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Liu-Honghui",
"name": {
"family": "Liu",
"given": "Honghui"
}
},
{
"id": "Abdikamalov-A-B",
"name": {
"family": "Abdikamalov",
"given": "Askar B."
}
},
{
"id": "Ayzenberg-D",
"name": {
"family": "Ayzenberg",
"given": "Dimitry"
}
},
{
"id": "Bambi-C",
"name": {
"family": "Bambi",
"given": "Cosimo"
},
"orcid": "0000-0002-3180-9502"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Nampalliwar-S",
"name": {
"family": "Nampalliwar",
"given": "Sourabh"
}
}
]
},
"title": "Testing the Kerr hypothesis using x-ray reflection spectroscopy with NuSTAR data of Cygnus X-1 in the soft state",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2019 American Physical Society. \n\nReceived 19 April 2019; published 11 June 2019. \n\nWe thank Dominic Walton for providing us his xstar table. This work was supported by the Innovation Program of the Shanghai Municipal Education Commission, Grant No. 2019-01-07-00-07-E00035, and Fudan University, Grant No. IDH1512060. A.\u2009B.\u2009A. also acknowledges the support from the Shanghai Government Scholarship (SGS). J.\u2009A.\u2009G. and S.\u2009N. acknowledge support from the Alexander von Humboldt Foundation. S.\u2009N. also acknowledges support from the Excellence Initiative at Eberhard-Karls Universit\u00e4t T\u00fcbingen.\n\nPublished - PhysRevD.99.123007.pdf
Submitted - 1904.08027.pdf
",
"abstract": "We continue exploring the constraining capabilities of x-ray reflection spectroscopy to test the Kerr-nature of astrophysical black holes, and we present the results of our analysis of two NuSTAR observations of Cygnus X-1 in the soft state. We find that the final measurement can strongly depend on the assumption of the intensity profile. We conclude that Cygnus X-1 is not suitable for tests of general relativity using x-ray reflection spectroscopy, and we discuss the desired properties of a source to be a good candidate for our studies.",
"date": "2019-06-15",
"date_type": "published",
"publication": "Physical Review D",
"volume": "99",
"number": "12",
"publisher": "American Physical Society",
"pagerange": "Art. No. 123007",
"id_number": "CaltechAUTHORS:20190611-092516240",
"issn": "2470-0010",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190611-092516240",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Shanghai Municipal Education Commission",
"grant_number": "2019-01-07-00-07-E00035"
},
{
"agency": "Fudan University",
"grant_number": "IDH1512060"
},
{
"agency": "Shanghai Government Scholarship"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Eberhard-Karls Universit\u00e4t T\u00fcbingen"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1103/PhysRevD.99.123007",
"primary_object": {
"basename": "1904.08027.pdf",
"url": "https://authors.library.caltech.edu/records/z3kwe-azj32/files/1904.08027.pdf"
},
"related_objects": [
{
"basename": "PhysRevD.99.123007.pdf",
"url": "https://authors.library.caltech.edu/records/z3kwe-azj32/files/PhysRevD.99.123007.pdf"
}
],
"pub_year": "2019",
"author_list": "Liu, Honghui; Abdikamalov, Askar B.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5985r-xd694",
"eprint_id": 93184,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:00:22",
"lastmod": "2026-03-31 14:45:16",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Pintore-F",
"name": {
"family": "Pintore",
"given": "F."
}
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "On the magnetic field in M51 ULX-8",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013X-rays: binaries",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 February 7. Received 2019 February 7; in original form 2018 June 13. Published: 19 February 2019. \n\nThe authors thank the anonymous referee. MJM and DJW appreciate support from Ernest Rutherford STFC fellowships.\n\nPublished - stz436.pdf
Submitted - 1902.04058.pdf
",
"abstract": "The reported discovery of a cyclotron resonance scattering feature (CRSF) in the spectrum of M51 ULX-8 may provide an important clue as to the nature of the magnetic field in those ultraluminous X-ray sources hosting neutron stars. In this paper, we present the covariance (linearly correlated variability) spectrum of M51 ULX-8 on long (>2000\u2009s) time-scales. This allows us to unambiguously decompose the spectrum which requires multiple components in order to explain the broadband emission. Having a clearer picture of the spectral decomposition leads to various tests for the dipole field strength of the neutron star which can be extended to other ULXs when certain criteria are met. In the case of M51 ULX-8, we rule out a very strong (10^(15) G) dipole solution with either a sub- or supercritical disc. Instead, our tests indicate an upper limit on the dipole field of 10^(12) G and a classical supercritical inflow, similar to that inferred in other ULXs found to harbour neutron stars, although we do not rule out the presence of an additional, strong (10^(15) G) multipole field falling off steeply with distance from the neutron star.",
"date": "2019-06",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "486",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "2-9",
"id_number": "CaltechAUTHORS:20190222-103643130",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190222-103643130",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stz436",
"primary_object": {
"basename": "1902.04058.pdf",
"url": "https://authors.library.caltech.edu/records/5985r-xd694/files/1902.04058.pdf"
},
"related_objects": [
{
"basename": "stz436.pdf",
"url": "https://authors.library.caltech.edu/records/5985r-xd694/files/stz436.pdf"
}
],
"pub_year": "2019",
"author_list": "Middleton, M. J.; Brightman, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7gsz0-epj14",
"eprint_id": 97411,
"eprint_status": "archive",
"datestamp": "2023-08-19 16:06:06",
"lastmod": "2026-03-31 16:17:57",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Grupe-D",
"name": {
"family": "Grupe",
"given": "Dirk"
},
"orcid": "0000-0002-9961-3661"
},
{
"id": "Komossa-S",
"name": {
"family": "Komossa",
"given": "S."
}
},
{
"id": "Gallo-L-C",
"name": {
"family": "Gallo",
"given": "Luigi"
}
},
{
"id": "Schartel-N",
"name": {
"family": "Schartel",
"given": "Norbert"
}
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "Michael"
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Santos-Lleo-M",
"name": {
"family": "Santos-Lleo",
"given": "Maria"
}
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Miniutti-G",
"name": {
"family": "Miniutti",
"given": "Giovanni"
}
}
]
},
"title": "Swift, NuStar and XMM-Newton observations of the NLS1 galaxy RX\u00a0J2317.8-4422 in an extreme X-ray low flux state",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: nuclei, quasars: individual: RX J2317.8\u20134422, galaxies: Seyfert",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nAccepted 2019 March 18. Received 2019 March 16; in original form 2019 January 17. \n\nWe thank our referee, Chris Done, for useful comments and suggestions that improved this paper. We would like to thank Neil Gehrels and Brad Cenko for approving our Target of Opportunity (ToO) requests and the Swift team for performing the ToO observations of RX J2317\u20134422. We also want to thank our Morehead State University students Mason Bush, Chelsea Pruett, Sonny Ernst, and Taylor Barber for looking through the Swift data to find AGNs in low X-ray flux states. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, Caltech, under contract with the National Aeronautics and Space Administration. Based on observations obtained with XMM-Newton, an European Space Agency (ESA) science mission with instruments and contributions directly funded by ESA Member States and NASA. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. ACF acknowledges European Research Council Advanced Grant 340442.\n\nPublished - stz819.pdf
Accepted Version - 1903.07689.pdf
",
"abstract": "We report the discovery of RX J2317.8\u20134422 in an extremely low X-ray flux state by the Neil Gehrels Swift observatory in 2014 April/May. In total, the low-energy X-ray emission dropped by a factor of 100. We have carried out multiwavelength follow-up observations of this narrow-line Seyfert 1 galaxy. Here we present observations with Swift, XMM\u2013Newton, and NuSTAR in 2014 October and November and further monitoring observations by Swift from 2015 to 2018. Compared with the beginning of the Swift observations in 2005, in the November 2014 XMM\u2013Newton and NuSTAR observations RX J2317\u20134422.8 dropped by a factor of about 80 in the 0.3\u201310\u2009keV band. While the high-state Swift observations can be interpreted by a partial covering absorption model with a moderate absorption column density of N_H = 5.4 \u00d7 10^(22)\u2009cm^(\u22122) or blurred reflection, due to the dominating background at energies above 2\u2009keV the low-state XMM\u2013Newton data cannot distinguish between different multicomponent models and were adequately fitted with a single power-law model. We discuss various scenarios like a long-term change of the accretion rate or absorption as the cause for the strong variability seen in RX J2317.8\u20134422.",
"date": "2019-06",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "486",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "227-235",
"id_number": "CaltechAUTHORS:20190725-125943820",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190725-125943820",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stz819",
"primary_object": {
"basename": "1903.07689.pdf",
"url": "https://authors.library.caltech.edu/records/7gsz0-epj14/files/1903.07689.pdf"
},
"related_objects": [
{
"basename": "stz819.pdf",
"url": "https://authors.library.caltech.edu/records/7gsz0-epj14/files/stz819.pdf"
}
],
"pub_year": "2019",
"author_list": "Grupe, Dirk; Komossa, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5exb9-thj37",
"eprint_id": 96552,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:56:54",
"lastmod": "2026-03-31 13:24:22",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hickox-R-C",
"name": {
"family": "Hickox",
"given": "R. C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Civano-Francesca",
"name": {
"family": "Civano",
"given": "F."
},
"orcid": "0000-0002-2115-1137"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Boorman-P-G",
"name": {
"family": "Boorman",
"given": "P. G."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Brandt-W-N",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "Canning-R-E-A",
"name": {
"family": "Canning",
"given": "R. E. A."
}
},
{
"id": "Fornasini-F",
"name": {
"family": "Fornasini",
"given": "F."
},
"orcid": "0000-0002-9286-9963"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Jones-M-L",
"name": {
"family": "Jones",
"given": "M. L."
}
},
{
"id": "Lansbury-G-B",
"name": {
"family": "Lansbury",
"given": "G. B."
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Lanz-L",
"name": {
"family": "Lanz",
"given": "L."
},
"orcid": "0000-0002-3249-8224"
},
{
"id": "Lanzuisi-G",
"name": {
"family": "Lanzuisi",
"given": "G."
},
"orcid": "0000-0001-9094-0984"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Marchesi-S",
"name": {
"family": "Marchesi",
"given": "S."
},
"orcid": "0000-0001-5544-0749"
},
{
"id": "Masini-A",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Ananna-T",
"name": {
"family": "Ananna",
"given": "T."
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
}
]
},
"title": "Resolving the cosmic X-ray background with a next-generation high-energy X-ray observatory",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Submitted - 1905.11439.pdf
",
"abstract": "The cosmic X-ray background (CXB), which peaks at an energy of \u224830 keV, is produced primarily by emission from accreting supermassive black holes (SMBHs). The CXB therefore serves as a constraint on the integrated SMBH growth in the Universe and the accretion physics and obscuration in active galactic nuclei (AGNs). This paper gives an overview of recent progress in understanding the high-energy (>~10 keV) X-ray emission from AGNs and the synthesis of the CXB, with an emphasis on results from NASA's NuSTAR hard X-ray mission. We then discuss remaining challenges and open questions regarding the nature of AGN obscuration and AGN physics. Finally, we highlight the exciting opportunities for a next-generation, high-resolution hard X-ray mission to achieve the long-standing goal of resolving and characterizing the vast majority of the accreting SMBHs that produce the CXB.",
"date": "2019-05-27",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20190619-095513937",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190619-095513937",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1905.11439",
"primary_object": {
"basename": "1905.11439.pdf",
"url": "https://authors.library.caltech.edu/records/5exb9-thj37/files/1905.11439.pdf"
},
"pub_year": "2019",
"author_list": "Hickox, R. C.; Civano, F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/759r9-q6z09",
"eprint_id": 100345,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:30:36",
"lastmod": "2026-03-31 14:39:31",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "D. Christopher"
},
"orcid": "0000-0002-8650-1644"
},
{
"id": "O'Sullivan-Donal",
"name": {
"family": "O'Sullivan",
"given": "Donal"
},
"orcid": "0000-0002-4959-9179"
},
{
"id": "Matuszweski-M",
"name": {
"family": "Matuszweski",
"given": "Mateusz"
}
},
{
"id": "Hamden-E-T",
"name": {
"family": "Hamden",
"given": "Erika"
},
"orcid": "0000-0002-3131-7372"
},
{
"id": "Dekel-A",
"name": {
"family": "Dekel",
"given": "Avishai"
},
"orcid": "0000-0003-4174-0374"
},
{
"id": "Lapiner-Sharon",
"name": {
"family": "Lapiner",
"given": "Sharon"
}
},
{
"id": "Morrissey-P",
"name": {
"family": "Morrissey",
"given": "Patrick"
},
"orcid": "0000-0001-8177-1023"
},
{
"id": "Neill-J-D",
"name": {
"family": "Neill",
"given": "James D."
},
"orcid": "0000-0002-0466-1119"
},
{
"id": "Cantalupo-S",
"name": {
"family": "Cantalupo",
"given": "Sebastiano"
},
"orcid": "0000-0001-5804-1428"
},
{
"id": "Prochaska-J-X",
"name": {
"family": "Prochaska",
"given": "J. Xavier"
},
"orcid": "0000-0002-7738-6875"
},
{
"id": "Steidel-C-C",
"name": {
"family": "Steidel",
"given": "Charles"
},
"orcid": "0000-0002-4834-7260"
},
{
"id": "Trainor-R-F",
"name": {
"family": "Trainor",
"given": "Ryan"
},
"orcid": "0000-0002-6967-7322"
},
{
"id": "Moore-A-M",
"name": {
"family": "Moore",
"given": "Anna"
},
"orcid": "0000-0002-2894-6936"
},
{
"id": "Ceverino-D",
"name": {
"family": "Ceverino",
"given": "Daniel"
},
"orcid": "0000-0002-8680-248X"
},
{
"id": "Primack-J-R",
"name": {
"family": "Primack",
"given": "Joel"
},
"orcid": "0000-0001-5091-5098"
},
{
"id": "Rizzi-L",
"name": {
"family": "Rizzi",
"given": "Luca"
},
"orcid": "0000-0003-0882-2327"
}
]
},
"title": "Multi-Filament Inflows Fueling Young Star Forming Galaxies",
"ispublished": "unpub",
"full_text_status": "public",
"note": "This work was supported by the National Science Foundation, the W. M Keck Observatory and the California Institute of Technology. The VELA simulations were performed at NASA Advanced Supercomputing (NAS) at NASA Ames Research Center. D.C. is funded by the ERC Advanced Grant, STARLIGHT: Formation of the First Stars (project number 339177). \n\nAuthor Contributions: D.C.M. is the Principal Investigator of KCWI, performed the analysis of the simulated galaxy, data and MFI models, and was principal author on the paper. D.O. and D.C.M led the observations of UM287 and CSO 38. D.O., M.M. reduced the data. D. O., M. M., and E. H. contributed to the paper writing. P.M., M.M., D.C.M., D.N., D.O., and A.M. designed, constructed, and operated KCWI. D.N., M.M. and D.C.M. developed the KCWI data pipeline and produced the final data cubes. D. C. developed the VELA simulations. A.D. and S. L. provided the simulated galaxy VELA07 and contributed to the paper. D.C. and J.P. contributed the cosmological simulation. C.S, R.T., S.C., and J.X.P. contributed to the development of KCWI, Keck data for the two protogalaxies, and to the editing of the paper. L. R. made major contributions to KCWI commissioning and participated in the observations of CSO 38. \n\nCode and Data Availability: KCWI pipeline code is available on the W. M. Keck Observatory website. KCWI data on CSO38 and UM287 is publically available. Data on UM287 will be available 18 months after the observation in Oct 2017. The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.\n\nSubmitted - 1904.11465.pdf
",
"abstract": "Theory suggests that there are two primary modes of accretion through which dark matter halos acquire the gas to form and fuel galaxies, hot and cold mode accretion. In cold mode accretion, gas streams along cosmic web filaments to the center of the halo, allowing for the efficient delivery of star-forming fuel. Recently, two QSO-illuminated HI Lyman alpha (Ly{\\alpha}) emitting objects were reported to have properties of cold, rotating structures (Martin et al. 2015, Martin et al. 2016). However, the spatial and spectral resolution available was insufficient to constrain radial flows associated with connecting filaments. With the Keck Cosmic Web Imager (KCWI) we now have eight times the spatial resolution, permitting the detection of these in-spiraling flows. In order to detect these inflows, we introduce a suite of models which incorporate zonal radial flows, demonstrate their performance on a numerical simulation that exhibits coldflow accretion, and show that they are an excellent match to KCWI velocity maps of two Ly{\\alpha} emitters observed around high-redshift quasars. These Multi-Filament Inflow models kinematically isolate zones of radial inflow that correspond to extended filamentary emission. The derived gas flux and inflow path is sufficient to fuel the inferred central galaxy star formation rate and angular momentum. Thus, our kinematic emission maps provide strong evidence for the inflow of gas from the cosmic web building galaxies at the peak of star formation.",
"date": "2019-04-25",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20191218-101527501",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191218-101527501",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF"
},
{
"agency": "W. M. Keck Observatory"
},
{
"agency": "Caltech"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "339177"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.48550/arXiv.1904.11465",
"primary_object": {
"basename": "1904.11465.pdf",
"url": "https://authors.library.caltech.edu/records/759r9-q6z09/files/1904.11465.pdf"
},
"pub_year": "2019",
"author_list": "Martin, D. Christopher; O'Sullivan, Donal; et al."
},
{
"id": "https://authors.library.caltech.edu/records/bx3tn-d5v69",
"eprint_id": 94889,
"eprint_status": "archive",
"datestamp": "2023-08-22 01:26:07",
"lastmod": "2026-03-31 15:04:21",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Li-Qiong",
"name": {
"family": "Li",
"given": "Qiong"
},
"orcid": "0000-0002-3119-9003"
},
{
"id": "Cai-Zheng",
"name": {
"family": "Cai",
"given": "Zheng"
},
"orcid": "0000-0001-8467-6478"
},
{
"id": "Prochaska-J-X",
"name": {
"family": "Prochaska",
"given": "J. Xavier"
},
"orcid": "0000-0002-7738-6875"
},
{
"id": "Arrigoni-Battaia-F",
"name": {
"family": "Arrigoni-Battaia",
"given": "Fabrizio"
},
"orcid": "0000-0002-4770-6137"
},
{
"id": "Ivison-R-J",
"name": {
"family": "Ivison",
"given": "R. J."
},
"orcid": "0000-0001-5118-1313"
},
{
"id": "Falgarone-E",
"name": {
"family": "Falgarone",
"given": "Edith"
}
},
{
"id": "Cantalupo-S",
"name": {
"family": "Cantalupo",
"given": "Sebastiano"
},
"orcid": "0000-0001-5804-1428"
},
{
"id": "Matuszewski-M",
"name": {
"family": "Matuszewski",
"given": "Mateusz"
}
},
{
"id": "Neill-J-D",
"name": {
"family": "Neill",
"given": "James Don"
},
"orcid": "0000-0002-0466-1119"
},
{
"id": "Wang-Ran",
"name": {
"family": "Wang",
"given": "Ran"
},
"orcid": "0000-0003-4956-5742"
},
{
"id": "Martin-D-Christopher",
"name": {
"family": "Martin",
"given": "Christopher"
},
"orcid": "0000-0002-8650-1644"
},
{
"id": "Moore-A-M",
"name": {
"family": "Moore",
"given": "Anna"
},
"orcid": "0000-0002-2894-6936"
}
]
},
"title": "Discovery of a Ly\u03b1-emitting Dark Cloud within the z \u223c 2.8 SMM J02399-0136 System",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "cosmology: observations; galaxies: formation; galaxies: high-redshift; intergalactic medium; quasars: general",
"note": "\u00a9 2019. The American Astronomical Society. \n\nReceived 2018 April 9; revised 2019 March 6; accepted 2019 March 7; published 2019 April 23. \n\nThis work was supported by National Key Program for Science and Technology Research and Development (grant 2016YFA0400703) and the National Science Foundation of China (11721303). We are thankful for the support from the National Science Foundation of China (NSFC) grants No. 11373008, 11533001. Q.L. gratefully acknowledges financial support from China Scholarship Council. Z.C. acknowledges the supports provided by NASA through the Hubble Fellowship grant HST-HF2-51370 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5-26555. E.F. gratefully acknowledges funding from the European Research Council, under the European Community's Seventh framework Programme, through the Advanced Grant MIST (FP7/2017-2022, No. 742719). S.C. gratefully acknowledges support from Swiss National Science Foundation grant PP00P2_163824. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.\n\nPublished - Li_2019_ApJ_875_130.pdf
",
"abstract": "We present Keck/Keck Cosmic Web Imager (KCWI) integral field spectrograph observations of the complex system surrounding SMM J02399\u22120136 (a lensed z = 2.8 sub-mm galaxy), including an associated Ly\u03b1 nebula, a dust-obscured, broad-absorption-line quasar, and neighboring galaxies. At a 3\u03c3 surface brightness contour of 1.6 \u00d7 10^(\u221217) erg s^(\u22121) cm^(\u22122) arcsec^(\u22122), the Ly\u03b1 nebula extends over 17 arcsec (\u2273 140 physical kpc) and has a total Ly\u03b1 luminosity of 2.5 \u00d7 10^(44) erg s^(-1) (uncorrected for lensing). The nebula exhibits a kinematic shear of ~ 1000 km s^(-1) over 100 pkpc with lowest velocities east of SMM J02399\u22120136 and increasing to the southwest. We also discover a bright, Ly\u03b1 emitter, separated spatially and kinematically from the nebula, at a projected separation of \u224860 kpc from the quasar. This source has no clear central counterpart in deep Hubble Space Telescope imaging, giving an intrinsic Ly\u03b1 rest-frame equivalent width greater than 312 \u00c5 (5\u03c3). We argue that this \"dark cloud\" is illuminated by the quasar with a UV flux that is orders of magnitude brighter than the emission along our sightline. This result confirms statistical inferences that luminous quasars at z > 2 emit UV radiation anisotropically. Future KCWI observations of other lines, e.g., Ly\u03b2, He ii, C iv, etc, and with polarimetry will further reveal the origin of the Ly\u03b1 nebula and nature of the dark cloud.",
"date": "2019-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "875",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 130",
"id_number": "CaltechAUTHORS:20190423-095739444",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190423-095739444",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Key Basic Research Program of China",
"grant_number": "2016YFA0400703"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11721303"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11373008"
},
{
"agency": "National Natural Science Foundation of China",
"grant_number": "11533001"
},
{
"agency": "China Scholarship Council"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF2-51370"
},
{
"agency": "NASA",
"grant_number": "NAS 5-26555"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "742719"
},
{
"agency": "Swiss National Science Foundation (SNSF)",
"grant_number": "PP00P2_163824"
},
{
"agency": "W. M. Keck Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab0e6f",
"primary_object": {
"basename": "Li_2019_ApJ_875_130.pdf",
"url": "https://authors.library.caltech.edu/records/bx3tn-d5v69/files/Li_2019_ApJ_875_130.pdf"
},
"pub_year": "2019",
"author_list": "Li, Qiong; Cai, Zheng; et al."
},
{
"id": "https://authors.library.caltech.edu/records/yz7y9-qrd86",
"eprint_id": 94952,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:28:15",
"lastmod": "2026-03-31 15:49:17",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Brumback-M-C",
"name": {
"family": "Brumback",
"given": "McKinley C."
},
"orcid": "0000-0002-4024-6967"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix S."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
}
]
},
"title": "Observing the Transient Pulsations of SMC X-1 with NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 stars: neutron \u2013 X-rays: binaries \u2013 X-rays: individual (SMC X-1)",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 October 8; revised 2019 March 10; accepted 2019 March 11; published 2019 April 24. \n\nThis work was supported under NASA grant No. NNG08FD60C, and made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). We would also like to thank the anonymous referee for providing helpful comments that helped to improve the quality of this paper. \n\nSoftware: Stingray (Huppenkothen et al. 2016), HENDRICS (Bachetti 2015), NUSTARDAS, MaLTPyNT (Bachetti 2015), DS9 (Joye & Mandel 2003).\n\nPublished - Pike_2019_ApJ_875_144.pdf
Accepted Version - 1903.06306.pdf
",
"abstract": "We report on Nuclear Spectroscopic Telescope Array observations of transient pulsations in the neutron star X-ray binary SMC X-1. The transition from nonpulsing to pulsing states was not accompanied by a large change in flux. Instead, both pulsing and nonpulsing states were observed in a single observation during the low-flux super-orbital state. During the high state, we measure a pulse period of P = 0.70117(9) s at T_(ref) = 56145 MJD. Spectral analysis during nonpulsing and pulsing states reveals that the observations can be consistently modeled by an absorbed power law with a phenomenological cutoff resembling a Fermi\u2013Dirac distribution, or by a partially obscured cutoff power law. The shapes of the underlying continua show little variability between epochs, while the covering fraction and column density vary between super-orbital states. The strength of pulsations also varies, leading us to infer that the absence and reemergence of pulsations are related to changing obscuration, such as by a warped accretion disk. SMC X-1 is accreting near or above its Eddington limit, reaching an unabsorbed X-ray luminosity of L_X(2\u201310 keV) \u2248 5 \u00d7 10^(38) erg s^(\u22121). This suggests that SMC X-1 may be a useful local analog to ultraluminous X-ray pulsars (ULXPs), which likewise exhibit strong variability in their pulsed fractions, as well as flux variability on similar timescales. In particular, the gradual pulse turn-on, which has been observed in M82 X-2, is similar to the behavior we observe in SMC X-1. Thus we propose that pulse fraction variability of ULXPs may also be due to variable obscuration.",
"date": "2019-04-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "875",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 144",
"id_number": "CaltechAUTHORS:20190424-160205673",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190424-160205673",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab0f2b",
"primary_object": {
"basename": "1903.06306.pdf",
"url": "https://authors.library.caltech.edu/records/yz7y9-qrd86/files/1903.06306.pdf"
},
"related_objects": [
{
"basename": "Pike_2019_ApJ_875_144.pdf",
"url": "https://authors.library.caltech.edu/records/yz7y9-qrd86/files/Pike_2019_ApJ_875_144.pdf"
}
],
"pub_year": "2019",
"author_list": "Pike, Sean N.; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vbzca-bev16",
"eprint_id": 94366,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:18:01",
"lastmod": "2026-03-30 23:53:57",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Gotthelf-E-V",
"name": {
"family": "Gotthelf",
"given": "E. V."
},
"orcid": "0000-0003-3847-3957"
},
{
"id": "Halpern-J-P",
"name": {
"family": "Halpern",
"given": "J. P."
}
},
{
"id": "Alford-J-A-J",
"name": {
"family": "Alford",
"given": "J. A. J."
}
},
{
"id": "Mihara-T",
"name": {
"family": "Mihara",
"given": "T."
}
},
{
"id": "Negoro-H",
"name": {
"family": "Negoro",
"given": "H."
}
},
{
"id": "Kawai-Nobuyuki",
"name": {
"family": "Kawai",
"given": "N."
},
"orcid": "0000-0001-9656-0261"
},
{
"id": "Dai-Y-Sophia",
"name": {
"family": "Dai",
"given": "S."
},
"orcid": "0000-0002-7928-416X"
},
{
"id": "Lower-M-E",
"name": {
"family": "Lower",
"given": "M. E."
},
"orcid": "0000-0001-9208-0009"
},
{
"id": "Johnston-S",
"name": {
"family": "Johnston",
"given": "S."
}
},
{
"id": "Bailes-M",
"name": {
"family": "Bailes",
"given": "M."
},
"orcid": "0000-0003-3294-3081"
},
{
"id": "Os\u0142owski-S",
"name": {
"family": "Os\u0142owski",
"given": "S."
},
"orcid": "0000-0003-0289-0732"
},
{
"id": "Camilo-F",
"name": {
"family": "Camilo",
"given": "F."
},
"orcid": "0000-0002-1873-3718"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "H."
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "2018 X-Ray and Radio Outburst of Magnetar XTE J1810\u2013197",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "pulsars: general \u2013 pulsars: individual (XTE J1810\u2013197) \u2013 stars: neutron \u2013 X-rays: stars",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 February 21; revised 2019 March 14; accepted 2019 March 15; published 2019 April 2. \n\nThe NuSTAR mission is a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Director for timely approval of this observation of XTE J1810\u2212197, and the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of the observation. We thank the UTMOST team and the University of Sydney for maintaining the Molonglo Observatory. E.V.G. acknowledges NASA ADAP Grant NNX16AF30G. M.B. acknowledges ARC grant LF150100148. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research also made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. We also acknowledge use of the Astronomer's Telegram (ATel) and the NASA Astrophysics Data Service (ADS).\n\nPublished - Gotthelf_2019_ApJL_874_L25.pdf
Submitted - 1902.08358.pdf
",
"abstract": "We present the earliest X-ray observations of the 2018 outburst of XTE J1810\u2212197, the first outburst since its 2003 discovery as the prototypical transient and radio-emitting anomalous X-ray pulsar (AXP). The Monitor of All-sky X-ray Image (MAXI) detected XTE J1810\u2212197 immediately after a November 20\u201326 visibility gap, contemporaneous with its reactivation as a radio pulsar, first observed on December 8. On December 13 the Nuclear Spectroscopic Telescope Array (NuSTAR) detected X-ray emission up to at least 30 keV, with a spectrum well-characterized by a blackbody plus power-law model with temperature kT = 0.74 \u00b1 0.02 keV and photon index \u0393 = 4.4 \u00b1 0.2 or by a two-blackbody model with kT = 0.59 \u00b1 0.04 keV and kT = 1.0 \u00b1 0.1 keV, both including an additional power-law component to account for emission above 10 keV, with \u0393_h = \u22120.2 \u00b1 1.5 and \u0393_h = 1.5 \u00b1 0.5, respectively. The latter index is consistent with hard X-ray flux reported for the nontransient magnetars. In the 2\u201310 keV bandpass, the absorbed flux is 2 \u00d7 10^(\u221210) erg s^(\u22121) cm^(\u22122), a factor of 2 greater than the maximum flux extrapolated for the 2003 outburst. The peak of the sinusoidal X-ray pulse lags the radio pulse by \u22480.13 cycles, consistent with their phase relationship during the 2003 outburst. This suggests a stable geometry in which radio emission originates on magnetic field lines containing currents that heat a spot on the neutron star surface. However, a measured energy-dependent phase shift of the pulsed X-rays suggests that all X-ray emitting regions are not precisely coaligned.",
"date": "2019-04-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "874",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L25",
"id_number": "CaltechAUTHORS:20190402-112157216",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190402-112157216",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NNX16AF30G"
},
{
"agency": "Australian Research Council",
"grant_number": "LF150100148"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/ab101a",
"primary_object": {
"basename": "1902.08358.pdf",
"url": "https://authors.library.caltech.edu/records/vbzca-bev16/files/1902.08358.pdf"
},
"related_objects": [
{
"basename": "Gotthelf_2019_ApJL_874_L25.pdf",
"url": "https://authors.library.caltech.edu/records/vbzca-bev16/files/Gotthelf_2019_ApJL_874_L25.pdf"
}
],
"pub_year": "2019",
"author_list": "Gotthelf, E. V.; Halpern, J. P.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ad9jg-fmw54",
"eprint_id": 93175,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:17:38",
"lastmod": "2026-03-31 15:54:48",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Nardini-E",
"name": {
"family": "Nardini",
"given": "E."
},
"orcid": "0000-0001-9226-8992"
},
{
"id": "Gallo-L-C",
"name": {
"family": "Gallo",
"given": "L. C."
}
},
{
"id": "Reynolds-M-T",
"name": {
"family": "Reynolds",
"given": "M. T."
}
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Risaliti-G",
"name": {
"family": "Risaliti",
"given": "G."
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
}
]
},
"title": "A low-flux state in IRAS\u200900521\u22127054 seen with NuSTAR and XMM\u2013Newton: relativistic reflection and an ultrafast outflow",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: active \u2013 X-rays: individual: (IRAS 00521\u22127054)",
"note": "\u00a9 2019 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 January 1. Received 2018 December 19; in original form 2018 November 8. Published: 16 January 2019. \n\nThe authors would like to thank the reviewer for their feedback, which helped improve the clarity of the final version of the manuscript, and C. Done for useful discussion. DJW acknowledges support from an STFC Ernest Rutherford Fellowship; EN acknowledges funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sk\u0142odowska-Curie grant agreement no. 664931; CR acknowledges the CONICYT + PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a\u00f1o 2017 PAI77170080; ACF acknowledges support from ERC Advanced Grant 340442; JAG acknowledges support from NASA grant NNX17AJ65G and from the Alexander von Humboldt Foundation. \n\nThis research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). This research has also made use of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States.\n\nPublished - stz115.pdf
Accepted Version - 1901.05016.pdf
",
"abstract": "We present results from a deep, coordinated XMM\u2013Newton + NuSTARobservation of the Seyfert 2 galaxy IRAS\u200900521\u22127054. The NuSTAR data provide the first detection of this source in high-energy X-rays (E > 10\u2009keV), and the broad-band data show this to be a highly complex source which exhibits relativistic reflection from the inner accretion disc, further reprocessing by more distant material, neutral absorption, and evidence for ionized absorption in an extreme, ultrafast outflow (\u2060v_(out) \u223c 0.4c). Based on lamppost disc reflection models, we find evidence that the central supermassive black hole is rapidly rotating (a > 0.77), consistent with previous estimates from the profile of the relativistic iron line, and that the accretion disc is viewed at a fairly high inclination (i \u223c 59\u00b0). Based on extensive simulations, we find the ultrafast outflow is detected at \u223c4\u03c3 significance (or greater). We also estimate that the extreme outflow should be sufficient to power galaxy-scale feedback, and may even dominate the energetics of the total output from the system.",
"date": "2019-04-01",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "484",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2544-2555",
"id_number": "CaltechAUTHORS:20190222-073613522",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190222-073613522",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "664931"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PAI77170080"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "NASA",
"grant_number": "NNX17AJ65G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stz115",
"primary_object": {
"basename": "1901.05016.pdf",
"url": "https://authors.library.caltech.edu/records/ad9jg-fmw54/files/1901.05016.pdf"
},
"related_objects": [
{
"basename": "stz115.pdf",
"url": "https://authors.library.caltech.edu/records/ad9jg-fmw54/files/stz115.pdf"
}
],
"pub_year": "2019",
"author_list": "Walton, D. J.; Nardini, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3mmw8-84f32",
"eprint_id": 94308,
"eprint_status": "archive",
"datestamp": "2023-08-22 01:18:13",
"lastmod": "2026-03-30 23:33:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Tripathi-A",
"name": {
"family": "Tripathi",
"given": "Ashutosh"
},
"orcid": "0000-0002-3960-5870"
},
{
"id": "Yan-Jinli",
"name": {
"family": "Yan",
"given": "Jinli"
}
},
{
"id": "Yang-Yuchan",
"name": {
"family": "Yang",
"given": "Yuchan"
}
},
{
"id": "Yan-Yunfeng",
"name": {
"family": "Yan",
"given": "Yunfeng"
}
},
{
"id": "Garnham-M",
"name": {
"family": "Garnham",
"given": "Marcus"
}
},
{
"id": "Yao-Yu",
"name": {
"family": "Yao",
"given": "Yu"
}
},
{
"id": "Li-Songcheng",
"name": {
"family": "Li",
"given": "Songcheng"
}
},
{
"id": "Ding-Ziyu",
"name": {
"family": "Ding",
"given": "Ziyu"
}
},
{
"id": "Abdikamalov-A-B",
"name": {
"family": "Abdikamalov",
"given": "Askar B."
}
},
{
"id": "Ayzenberg-D",
"name": {
"family": "Ayzenberg",
"given": "Dimitry"
}
},
{
"id": "Bambi-C",
"name": {
"family": "Bambi",
"given": "Cosimo"
},
"orcid": "0000-0002-3180-9502"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Nampalliwar-S",
"name": {
"family": "Nampalliwar",
"given": "Sourabh"
}
}
]
},
"title": "Constraints on the Spacetime Metric around Seven \"Bare\" AGNs Using X-Ray Reflection Spectroscopy",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks; black hole physics; gravitation",
"note": "\u00a9 2019. The American Astronomical Society. \n\nReceived 2019 January 12; revised 2019 February 15; accepted 2019 February 23; published 2019 April 1. \n\nThis work was supported by the National Natural Science Foundation of China (NSFC), grant No. U1531117, and Fudan University, grant No. IDH1512060. A.T. also acknowledges support from the China Scholarship Council (CSC), grant No. 2016GXZR89. A.B.A. also acknowledges the support from the Shanghai Government Scholarship (SGS). J.A.G. acknowledges support from the Alexander von Humboldt Foundation. J.J. is supported by the Cambridge Trust and the Chinese Scholarship Council Joint Scholarship Programme (201604100032). S.N. acknowledges support from the Excellence Initiative at Eberhard-Karls Universit\u00e4t T\u00fcbingen.\n\nPublished - Tripathi_2019_ApJ_874_135.pdf
Submitted - 1901.03064.pdf
",
"abstract": "We present the study of a sample of seven \"bare\" active galactic nuclei observed with Suzaku. We interpret the spectrum of these sources with a relativistic reflection component and we employ our model relxill_nk to test the Kerr nature of their supermassive black holes. We constrain the Johannsen deformation parameters \u03b1_(13) and \u03b1_(22), in which the Kerr metric is recovered when \u03b1_(13) = \u03b1_(22) = 0. All our measurements are consistent with the hypothesis that the spacetime geometry around these supermassive objects is described by the Kerr solution. For some sources, we obtain quite strong constraints on \u03b1_(13) and \u03b1_(22) when compared to those found in our previous studies. We discuss the systematic uncertainties in our tests and the implications of our results.",
"date": "2019-04-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "874",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 135",
"id_number": "CaltechAUTHORS:20190401-084307071",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190401-084307071",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1531117"
},
{
"agency": "Fudan University",
"grant_number": "IDH1512060"
},
{
"agency": "China Scholarship Council",
"grant_number": "2016GXZR89"
},
{
"agency": "Shanghai Government Scholarship"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "China Scholarship Council",
"grant_number": "201604100032"
},
{
"agency": "Cambridge Trust"
},
{
"agency": "Eberhard-Karls Universit\u00e4t T\u00fcbingen"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab0a00",
"primary_object": {
"basename": "1901.03064.pdf",
"url": "https://authors.library.caltech.edu/records/3mmw8-84f32/files/1901.03064.pdf"
},
"related_objects": [
{
"basename": "Tripathi_2019_ApJ_874_135.pdf",
"url": "https://authors.library.caltech.edu/records/3mmw8-84f32/files/Tripathi_2019_ApJ_874_135.pdf"
}
],
"pub_year": "2019",
"author_list": "Tripathi, Ashutosh; Yan, Jinli; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3xwe9-g3r14",
"eprint_id": 94729,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:12:01",
"lastmod": "2026-03-31 00:05:57",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Wang-Jingyi",
"name": {
"family": "Wang",
"given": "Jingyi"
},
"orcid": "0000-0002-1742-2125"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
}
]
},
"title": "High-density reflection spectroscopy: I. A case study of GX\u00a0339-4",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013X-rays: binaries \u2013 X-rays: individual (GX 339-4)",
"note": "\u00a9 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2019 January 6. Received 2019 January 6; in original form 2018 November 26. Published: 10 January 2019. \n\nJJ acknowledges support by the Cambridge Trust and the Chinese Scholarship Council Joint Scholarship Programme (201604100032). DJW acknowledges support from an STFC Ernest Rutherford Fellowship. ACF acknowledges support by the ERC Advanced Grant 340442. MLP is supported by European Space Agency (ESA) Research Fellowships. JFS has been supported by NASA Einstein Fellowship grant No. PF5-160144. JAG acknowledges support from the Alexander von Humboldt Foundation. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center and the California Institute of Technology. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. We acknowledge support from European Space Astronomy Center (ESAC).\n\nPublished - stz095.pdf
Accepted Version - 1901.01739.pdf
",
"abstract": "We present a broad-band spectral analysis of the black hole binary GX 339-4 with NuSTAR and Swift using high-density reflection model. The observations were taken when the source was in low-flux (LF) hard states during the outbursts in 2013 and 2015, and in a very high-flux (HF) soft state in 2015. The high-density reflection model can explain its LF spectra with no requirement for an additional low temperature thermal component. This model enables us to constrain the density in the disc surface of GX 339-4 in different flux states. The disc density in the LF state is log\u2009(ne/\u2009cm^(\u22123)) \u2248 21, 100 times higher than the density in the HF state (log\u2009(n_e/\u2009cm^(\u22123)) = 18.93^(+0.12)_(\u22120.16). A close-to-solar iron abundance is obtained by modelling the LF and HF broad-band spectra with variable density reflection model (\u2060Z_(Fe) = 1.50^(+0.12)_(\u22120.04)Z\u2299 and Z_(Fe) = 1.05^(+0.17)_(\u22120.15)Z\u2299, respectively).",
"date": "2019-04",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "484",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "1972-1982",
"id_number": "CaltechAUTHORS:20190416-083122873",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190416-083122873",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Cambridge Trust"
},
{
"agency": "Chinese Scholarship Council",
"grant_number": "201604100032"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA Einstein Fellowship",
"grant_number": "PF5-160144"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stz095",
"primary_object": {
"basename": "stz095.pdf",
"url": "https://authors.library.caltech.edu/records/3xwe9-g3r14/files/stz095.pdf"
},
"related_objects": [
{
"basename": "1901.01739.pdf",
"url": "https://authors.library.caltech.edu/records/3xwe9-g3r14/files/1901.01739.pdf"
}
],
"pub_year": "2019",
"author_list": "Jiang, Jiachen; Fabian, Andrew C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/079rp-w0723",
"eprint_id": 96495,
"eprint_status": "archive",
"datestamp": "2023-08-19 15:01:45",
"lastmod": "2026-03-31 00:07:37",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Vulic-N",
"name": {
"family": "Vulic",
"given": "N."
},
"orcid": "0000-0001-7855-8336"
},
{
"id": "Hornschemeier-A-E",
"name": {
"family": "Hornschemeier",
"given": "A. E."
},
"orcid": "0000-0001-8667-2681"
},
{
"id": "Antoniou-V",
"name": {
"family": "Antoniou",
"given": "V."
},
"orcid": "0000-0001-7539-1593"
},
{
"id": "Basu-Zych-A-R",
"name": {
"family": "Basu-Zych",
"given": "A. R."
}
},
{
"id": "Binder-B",
"name": {
"family": "Binder",
"given": "B."
}
},
{
"id": "Fornasini-F-M",
"name": {
"family": "Fornasini",
"given": "F. M."
}
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Haberl-F",
"name": {
"family": "Haberl",
"given": "F."
}
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Lehmer-B-D",
"name": {
"family": "Lehmer",
"given": "B. D."
},
"orcid": "0000-0003-2192-3296"
},
{
"id": "Maccarone-T-J",
"name": {
"family": "Maccarone",
"given": "T. J."
},
"orcid": "0000-0003-0976-4755"
},
{
"id": "Ptak-A",
"name": {
"family": "Ptak",
"given": "A. F."
},
"orcid": "0000-0001-5655-1440"
},
{
"id": "Sivakoff-G-R",
"name": {
"family": "Sivakoff",
"given": "G. R."
},
"orcid": "0000-0001-6682-916X"
},
{
"id": "Tzanavaris-P",
"name": {
"family": "Tzanavaris",
"given": "P."
},
"orcid": "0000-0001-5737-5055"
},
{
"id": "Wik-D-R",
"name": {
"family": "Wik",
"given": "D. R."
},
"orcid": "0000-0001-8952-676X"
},
{
"id": "Williams-B-F",
"name": {
"family": "Williams",
"given": "B. F."
},
"orcid": "0000-0002-7502-0597"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Yukita-Mihoko",
"name": {
"family": "Yukita",
"given": "M."
},
"orcid": "0000-0001-6366-3459"
},
{
"id": "Zezas-A",
"name": {
"family": "Zezas",
"given": "A."
},
"orcid": "0000-0001-8952-676X"
}
]
},
"title": "Astro 2020 Science White Paper: Time Domain Studies of Neutron Star and Black Hole Populations: X-ray Identification of Compact Object Types",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Submitted - 1903.09858.pdf
",
"abstract": "What are the most important conditions and processes governing the growth of stellar-origin compact objects? The identification of compact object type as either black hole (BH) or neutron star (NS) is fundamental to understanding their formation and evolution. To date, time-domain determination of compact object type remains a relatively untapped tool. Measurement of orbital periods, pulsations, and bursts will lead to a revolution in the study of the demographics of NS and BH populations, linking source phenomena to accretion and galaxy parameters (e.g., star formation, metallicity). To perform these measurements over sufficient parameter space, a combination of a wide-field (>5000 deg^2) transient X-ray monitor over a dynamic energy range (~1-100 keV) and an X-ray telescope for deep surveys with <5 arcsec PSF half-energy width (HEW) angular resolution are required. Synergy with multiwavelength data for characterizing the underlying stellar population will transform our understanding of the time domain properties of transient sources, helping to explain details of supernova explosions and gravitational wave event rates.",
"date": "2019-03-23",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20190618-092213251",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190618-092213251",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.09858",
"primary_object": {
"basename": "1903.09858.pdf",
"url": "https://authors.library.caltech.edu/records/079rp-w0723/files/1903.09858.pdf"
},
"pub_year": "2019",
"author_list": "Vulic, N.; Hornschemeier, A. E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5cv6k-38w78",
"eprint_id": 98681,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:57:21",
"lastmod": "2026-03-31 05:38:53",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Reynolds-C-S",
"name": {
"family": "Reynolds",
"given": "Christopher"
}
},
{
"id": "Petre-R",
"name": {
"family": "Petre",
"given": "Robert"
}
},
{
"id": "Corcoran-M-F",
"name": {
"family": "Corcoran",
"given": "Michael"
}
},
{
"id": "Arnaud-K",
"name": {
"family": "Arnaud",
"given": "Keith"
}
},
{
"id": "Brandt-N",
"name": {
"family": "Brandt",
"given": "Niel"
}
},
{
"id": "Brenneman-L-W",
"name": {
"family": "Brenneman",
"given": "Laura"
}
},
{
"id": "Cornish-N-J",
"name": {
"family": "Cornish",
"given": "Neil"
}
},
{
"id": "Gonzales-G",
"name": {
"family": "Gonzales",
"given": "Gabriela"
}
},
{
"id": "Lopez-L-A",
"name": {
"family": "Lopez",
"given": "Laura"
},
"orcid": "0000-0002-1790-3148"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "High-Energy Astrophysics in the 2020s and Beyond",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Submitted - 1903.07760.pdf
",
"abstract": "With each passing decade, we gain new appreciation for the dynamic, connected, and often violent nature of the Universe. This reality necessarily places the study of high-energy processes at the very heart of modern astrophysics. This White Paper illustrates the central role of high-energy astrophysics to some of the most pressing astrophysical problems of our time, the formation/evolution of galaxies, the origin of the heavy elements, star and planet formation, the emergence of life on exoplanets, and the search for new physics. We also highlight the new connections that are growing between astrophysicists and plasma physicists. We end with a discussion of the challenges that must be addressed to realize the potential of these connections, including the need for integrated planning across physics and astronomy programs in multiple agencies, and the need to foster the creativity and career aspirations of individual scientists in this era of large projects.",
"date": "2019-03-18",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20190917-133815385",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-133815385",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.07760",
"primary_object": {
"basename": "1903.07760.pdf",
"url": "https://authors.library.caltech.edu/records/5cv6k-38w78/files/1903.07760.pdf"
},
"pub_year": "2019",
"author_list": "Reynolds, Christopher; Petre, Robert; et al."
},
{
"id": "https://authors.library.caltech.edu/records/byx2b-pjy19",
"eprint_id": 96557,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:56:54",
"lastmod": "2026-03-30 23:51:03",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "David R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Brenneman-L-W",
"name": {
"family": "Brenneman",
"given": "Laura"
}
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Connors-R-M-T",
"name": {
"family": "Connors",
"given": "Riley M."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "Fuerst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "Poshak"
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Kamraj-N",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "Jon M."
}
},
{
"id": "Nowak-M-A",
"name": {
"family": "Nowak",
"given": "Michael"
},
"orcid": "0000-0001-6923-1315"
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Reynolds-C-S",
"name": {
"family": "Reynolds",
"given": "Christopher"
}
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James"
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Taylor-C",
"name": {
"family": "Taylor",
"given": "Corbin"
}
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John"
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic"
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Zoghbi-A",
"name": {
"family": "Zoghbi",
"given": "Abderahmen"
},
"orcid": "0000-0002-0572-9613"
}
]
},
"title": "Probing the Black Hole Engine with Measurements of the Relativistic X-ray Reflection Component",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Submitted - 1903.07130.pdf
",
"abstract": "Over the last decades X-ray spectroscopy has proven to be a powerful tool for the estimation of black hole spin and several other key parameters in dozens of AGN and black hole X-ray binaries. In this White Paper, we discuss the observational and theoretical challenges expected in the exploration, discovery, and study of astrophysical black holes in the next decade. We focus on the case of accreting black holes and their electromagnetic signatures, with particular emphasis on the measurement of the relativistic reflection component in their X-ray spectra.",
"date": "2019-03-17",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20190619-103025261",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190619-103025261",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.07130",
"primary_object": {
"basename": "1903.07130.pdf",
"url": "https://authors.library.caltech.edu/records/byx2b-pjy19/files/1903.07130.pdf"
},
"pub_year": "2019",
"author_list": "Garc\u00eda, Javier A.; Bachetti, Matteo; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xmn7m-rrr02",
"eprint_id": 96477,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:55:49",
"lastmod": "2026-03-31 05:36:22",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Bachetti-Matteo",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "F\u00fcrst-Felix",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "B."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Heida-Marianne",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Kara-Erin",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Middleton-Matthew-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Tombesi-Francesco",
"name": {
"family": "Tombesi",
"given": "F."
},
"orcid": "0000-0002-6562-8654"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Breaking the limit: Super-Eddington accretion onto black holes and neutron stars",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Submitted - 1903.06844.pdf
",
"abstract": "With the recent discoveries of massive and highly luminous quasars at high redshifts (z\u223c7; e.g. Mortlock et al. 2011), the question of how black holes (BHs) grow in the early Universe has been cast in a new light. In order to grow BHs with M_(BH) > 10^9 M\u2299 by less than a billion years after the Big Bang, mass accretion onto the low-mass seed BHs needs to have been very rapid (Volonteri & Rees, 2005). Indeed, for any stellar remnant seed, the rate required would need to exceed the Eddington limit. This is the point at which the outward force produced by radiation pressure is equal to the gravitational attraction experienced by the in-falling matter. In principle, this implies that there is a maximum luminosity an object of mass M can emit; assuming spherical accretion and that the opacity is dominated by Thompson scattering, this Eddington luminosity is L_E = 1.38\u00d710^(38)(M/M\u2299) erg s^(\u22121). In reality, it is known that this limit can be violated, due to non-spherical geometry or various kinds of instabilities. Nevertheless, the Eddington limit remains an important reference point, and many of the details of how accretion proceeds above this limit remain unclear. Understanding how this so-called super-Eddington accretion occurs is of clear cosmological importance, since it potentially governs the growth of the first supermassive black holes (SMBHs) and the impact this growth would have had on their host galaxies ('feedback') and the epoch of reionization, as well as improving our understanding of accretion physics more generally.",
"date": "2019-03-15",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20190617-141021193",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190617-141021193",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.06844",
"primary_object": {
"basename": "1903.06844.pdf",
"url": "https://authors.library.caltech.edu/records/xmn7m-rrr02/files/1903.06844.pdf"
},
"pub_year": "2019",
"author_list": "Brightman, M.; Bachetti, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3zamc-51v78",
"eprint_id": 98682,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:51:28",
"lastmod": "2026-03-31 05:57:12",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kamraj-N",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "Anne"
}
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Probing the Physical Properties of the Corona in Accreting Black Holes",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "Formation and Evolution of Compact Objects, Galaxy Evolution",
"note": "Submitted - 1903.05241.pdf
",
"abstract": "The corona is a key component of most luminous accreting black holes, carrying 5 - 30 % of the power and in non-jetted Active Galactic Nuclei (AGN), creating all the X-ray emission above \u22431\u22122 keV. Its emission illuminates the inner accretion disc, creating the atomic line-rich reflection spectrum used to diagnose and map the accretion flow and measure black hole spin. The corona is likely powered magnetically by the strong differential rotation of the accretion disc and it may be intimately related to relativistic jets. Recent work shows that many black hole coronae may be dominated by electron-positron pairs produced by photon-photon collisions in the compact coronal environment. Despite the corona being an integral component of AGN and black hole binary systems, much is still unknown about the nature of the corona, such as its geometry, location, and the physical mechanisms powering the emission. In this white paper we explore our current understanding of coronal properties, such as its temperature, obtained from measurements with existing hard X-ray telescopes such as NuSTAR, and discuss important questions to be addressed in the coming decade surrounding the nature of the corona. Hard X-ray observations will continue to dispel the mystery of coronae and open up this part of the quasar engine to full understanding.",
"date": "2019-03-12",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20190917-134419227",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-134419227",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.05241",
"primary_object": {
"basename": "1903.05241.pdf",
"url": "https://authors.library.caltech.edu/records/3zamc-51v78/files/1903.05241.pdf"
},
"pub_year": "2019",
"author_list": "Kamraj, Nikita; Fabian, Andrew; et al."
},
{
"id": "https://authors.library.caltech.edu/records/dgec5-qdf76",
"eprint_id": 101099,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:50:35",
"lastmod": "2025-02-02 21:03:41",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Fields-B-D",
"name": {
"family": "Fields",
"given": "Brian D."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "Richard A."
},
"orcid": "0000-0003-2178-9111"
}
]
},
"title": "Near-Earth Supernova Explosions: Evidence, Implications, and Opportunities",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Astro2020 Science White Paper submitted to the 2020 Decadal Survey on Astronomy and Astrophysics.\n\nSubmitted - 1903.04589.pdf
",
"abstract": "There is now solid experimental evidence of at least one supernova explosion within 100 pc of Earth within the last few million years, from measurements of the short-lived isotope \u2076\u2070Fe in widespread deep-ocean samples, as well as in the lunar regolith and cosmic rays. This is the first established example of a specific dated astrophysical event outside the Solar System having a measurable impact on the Earth, offering new probes of stellar evolution, nuclear astrophysics, the astrophysics of the solar neighborhood, cosmic-ray sources and acceleration, multi-messenger astronomy, and astrobiology. Interdisciplinary connections reach broadly to include heliophysics, geology, and evolutionary biology. Objectives for the future include pinning down the nature and location of the established near-Earth supernova explosions, seeking evidence for others, and searching for other short-lived isotopes such as \u00b2\u2076Al and \u00b2\u2074\u2074Pu. The unique information provided by geological and lunar detections of radioactive \u2076\u2070Fe to assess nearby supernova explosions make now a compelling time for the astronomy community to advocate for supporting multi-disciplinary, cross-cutting research programs.",
"date": "2019-03-11",
"date_type": "published",
"id_number": "CaltechAUTHORS:20200204-081236612",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200204-081236612",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.04589",
"primary_object": {
"basename": "1903.04589.pdf",
"url": "https://authors.library.caltech.edu/records/dgec5-qdf76/files/1903.04589.pdf"
},
"pub_year": "2019",
"author_list": "Fields, Brian D. and Mewaldt, Richard A."
},
{
"id": "https://authors.library.caltech.edu/records/ashjm-6t581",
"eprint_id": 93194,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:48:29",
"lastmod": "2026-03-31 05:54:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Ptak-A",
"name": {
"family": "Ptak",
"given": "Andrew"
},
"orcid": "0000-0001-5655-1440"
},
{
"id": "Yukita-Mihoko",
"name": {
"family": "Yukita",
"given": "Mihoko"
},
"orcid": "0000-0001-6366-3459"
},
{
"id": "Zezas-A",
"name": {
"family": "Zezas",
"given": "Andreas"
},
"orcid": "0000-0001-8952-676X"
}
]
},
"title": "A ~60-day super-orbital period originating from the ultraluminous X-ray pulsar in M82",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: individual (M82) \u2013 stars: neutron \u2013 X-rays: binaries",
"note": "\u00a9 2019 The American Astronomical Society.\n\nReceived 2017 June 15; revised 2019 January 23; accepted 2019 January 24; published 2019 March 11.\n\nWe thank the anonymous referees and the statistics referee for their critical reviews and input on this paper, which improved it greatly. We would also like to thank Matthew Graham for valuable insight and discussion. M. Bachetti acknowledges support from the Fulbright Scholar Program and A. Zezas acknowledges funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007\u20132013)/ERC grant Agreement No. 617001. This project has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie RISE action, grant agreement No. 691164 (ASTROSTAT). The scientific results reported in this article are based on observations made by the Chandra X-ray Observatory. Support for this work was provided by the National Aeronautics and Space Administration through Chandra Award Number GO6-17080X issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application package ciao. We also acknowledge the use of public data from the Swift data archive.\n\nFacilities: Chandra (ACIS) - , Swift (XRT). -\n\nPublished - Brightman_2019_ApJ_873_115.pdf
Accepted Version - 1901.10491.pdf
",
"abstract": "Ultraluminous X-ray (ULX) pulsars are a new class of object powered by apparent super-critical accretion onto magnetized neutron stars. Three sources in this class have been identified so far; M82 X-2, NGC 5907 ULX-1, and NGC 7793 P13 have been found to have two properties in common; ~1 s spin periods, and for NGC 5907 ULX-1 and NGC 7793 P13 periodic X-ray flux modulations on timescales of ~60\u201380 days. M82 X-2 resides in a crowded field that includes the ULX M82 X-1 separated from X-2 by 5'', as well as other bright point sources. A 60 day modulation has been observed from the region, but the origin has been difficult to identify; both M82 X-1 and X-2 have been suggested as the source. In this paper we present the analysis of a systematic monitoring campaign by Chandra, the only X-ray telescope capable of resolving the crowded field. From a simple Lomb\u2013Scargle periodogram analysis and a more sophisticated Gaussian Process analysis we find that only X-2 exhibits a periodic signal around 60 days, supporting previous claims that it is the origin. We also construct a phase-averaged flux profile of the modulations from higher-cadence Swift/XRT data and find that the flux variations in the Chandra data are fully consistent with the flux profile. Since the orbit of the neutron star and its companion is known to be 2.5 days, the ~60 day period must be super-orbital in origin. The flux of the modulations varies by a factor of ~100 from the minimum to the maximum, with no evidence for spectral variations, making the origin difficult to explain.",
"date": "2019-03-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "873",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 115",
"id_number": "CaltechAUTHORS:20190225-080110226",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190225-080110226",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fulbright Foundation"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "617001"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "691164"
},
{
"agency": "NASA",
"grant_number": "GO6-17080X"
},
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab0215",
"primary_object": {
"basename": "1901.10491.pdf",
"url": "https://authors.library.caltech.edu/records/ashjm-6t581/files/1901.10491.pdf"
},
"related_objects": [
{
"basename": "Brightman_2019_ApJ_873_115.pdf",
"url": "https://authors.library.caltech.edu/records/ashjm-6t581/files/Brightman_2019_ApJ_873_115.pdf"
}
],
"pub_year": "2019",
"author_list": "Brightman, Murray; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/z0k54-jzg77",
"eprint_id": 98675,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:46:37",
"lastmod": "2025-02-02 20:59:14",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ray-P-S",
"name": {
"family": "Ray",
"given": "Paul S."
},
"orcid": "0000-0002-5297-5278"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "Fuerst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
}
]
},
"title": "STROBE-X: X-ray Timing and Spectroscopy on Dynamical Timescales from Microseconds to Years",
"ispublished": "unpub",
"full_text_status": "public",
"note": "The STROBE-X mission concept study is funded by the NASA Astrophysics Probes program (16-APROBES16-0008). The Italian authors acknowledge support from ASI, under agreement ASI-INAF n.2017-14-H.O, INAF and INFN. The Spanish authors acknowledge support from MINECO grant ESP2017-82674-R and FEDER funds. A.L.S. is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-1801792. A.L.W. acknowledges support from ERC Starting Grant 639217. \n\nWe gratefully acknowledge the superb engineering teams at the NASA/GSFC Instrument Design Lab and Mission Design Lab, Steve Kenyon, and Takashi Okajima, for their important contributions\nto the STROBE-X technical concept. We thank Lorenzo Amati and Giulia Stratta for useful discussions.\n\nSubmitted - 1903.03035.pdf
",
"abstract": "We present the Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X), a probe-class mission concept selected for study by NASA. It combines huge collecting area, high throughput, broad energy coverage, and excellent spectral and temporal resolution in a single facility. STROBE-X offers an enormous increase in sensitivity for X-ray spectral timing, extending these techniques to extragalactic targets for the first time. It is also an agile mission capable of rapid response to transient events, making it an essential X-ray partner facility in the era of time-domain, multi-wavelength, and multi-messenger astronomy. Optimized for study of the most extreme conditions found in the Universe, its key science objectives include: (1) Robustly measuring mass and spin and mapping inner accretion flows across the black hole mass spectrum, from compact stars to intermediate-mass objects to active galactic nuclei. (2) Mapping out the full mass-radius relation of neutron stars using an ensemble of nearly two dozen rotation-powered pulsars and accreting neutron stars, and hence measuring the equation of state for ultradense matter over a much wider range of densities than explored by NICER. (3) Identifying and studying X-ray counterparts (in the post-Swift era) for multiwavelength and multi-messenger transients in the dynamic sky through cross-correlation with gravitational wave interferometers, neutrino observatories, and high-cadence time-domain surveys in other electromagnetic bands. (4) Continuously surveying the dynamic X-ray sky with a large duty cycle and high time resolution to characterize the behavior of X-ray sources over an unprecedentedly vast range of time scales. STROBE-X's formidable capabilities will also enable a broad portfolio of additional science.",
"date": "2019-03-07",
"date_type": "published",
"id_number": "CaltechAUTHORS:20190917-110443914",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-110443914",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "16-APROBES16-0008"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "2017-14-H.0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "Istituto Nazionale di Fisica Nucleare (INFN)"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "ESP2017-82674-R"
},
{
"agency": "Fondo Europeo de Desarrollo Regional (FEDER)"
},
{
"agency": "NSF Astronomy and Astrophysics Fellowship",
"grant_number": "AST-1801792"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "639217"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1903.03035",
"primary_object": {
"basename": "1903.03035.pdf",
"url": "https://authors.library.caltech.edu/records/z0k54-jzg77/files/1903.03035.pdf"
},
"pub_year": "2019",
"author_list": "Ray, Paul S.; Fuerst, Felix; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4bqp6-1fh76",
"eprint_id": 94021,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:42:45",
"lastmod": "2026-03-31 16:10:04",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Rankin-J-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "McComas-D-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "N."
}
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "B. C."
}
}
]
},
"title": "Galactic Cosmic-Ray Anisotropies: Voyager 1 in the Local Interstellar Medium",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "astroparticle physics \u2013 cosmic rays \u2013 ISM: magnetic fields \u2013 scattering \u2013 shock waves \u2013 turbulence",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 December 4; revised 2019 January 22; accepted 2019 January 31; published 2019 March 4. \n\nWe thank E. Roelof for first suggesting particle trapping as a means for generating the anisotropy, R. Decker and the LECP team for providing background-corrected data, and E. Zirnstein for providing model-based information about the field enhancement toward the heliopause. This work was supported by NASA grant No. NNN12AA01C. J.S.R. and D.M. were also supported by the Interstellar Boundary Explorer (IBEX) mission, which is part of NASA's Explorer Program.\n\nPublished - Rankin_2019_ApJ_873_46.pdf
Accepted Version - 1905.11990.pdf
",
"abstract": "Since crossing the heliopause on 2012 August 25, Voyager 1 observed reductions in galactic cosmic ray count rates caused by a time-varying depletion of particles with pitch angles near 90\u00b0, while intensities of particles with other pitch angles remain unchanged. Between late 2012 and mid-2017, three large-scale events occurred, lasting from ~100 to ~630 days. Omnidirectional and directional high-energy data from Voyager 1's Cosmic Ray Subsystem are used to report cosmic ray intensity variations. Omnidirectional (\u227320 MeV) proton-dominated measurements show up to a 3.8% intensity reduction. Bidirectional (\u227370 MeV) proton-dominated measurements taken from various spacecraft orientations provide insight about the depletion region's spatial properties. We characterize the anisotropy as a \"notch\" in an otherwise uniform pitch angle distribution of varying depth and width centered about 90\u00b0 in pitch angle space. The notch averages 22\u00b0 wide and 15% deep, signifying a depletion region that is broad and shallow. There are indications that the anisotropy is formed by a combination of magnetic trapping and cooling downstream of solar-induced transient disturbances in a region that is also likely influenced by the highly compressed fields near the heliopause.",
"date": "2019-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "873",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 46",
"id_number": "CaltechAUTHORS:20190321-114830889",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190321-114830889",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/ab041f",
"primary_object": {
"basename": "1905.11990.pdf",
"url": "https://authors.library.caltech.edu/records/4bqp6-1fh76/files/1905.11990.pdf"
},
"related_objects": [
{
"basename": "Rankin_2019_ApJ_873_46.pdf",
"url": "https://authors.library.caltech.edu/records/4bqp6-1fh76/files/Rankin_2019_ApJ_873_46.pdf"
}
],
"pub_year": "2019",
"author_list": "Rankin, J. S.; Stone, E. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xm1rg-xjj17",
"eprint_id": 93193,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:41:53",
"lastmod": "2026-03-30 23:44:45",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-R-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Cackett-E-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Coughenour-B-M",
"name": {
"family": "Coughenour",
"given": "B. M."
}
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Degenaar-N",
"name": {
"family": "Degenaar",
"given": "N."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Paerels-F",
"name": {
"family": "Paerels",
"given": "F."
}
}
]
},
"title": "NuSTAR Observations of the Accreting Atolls GX 3+1, 4U 1702-429, 4U 0614+091, and 4U 1746-371",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 stars: neutron \u2013 stars: individual (GX 3+1, 4U 1746-371, 4U 1702-429, 4U\n0614+091) \u2013 X-rays: binaries",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 July 12; revised 2019 January 30; accepted 2019 January 31; published 2019 March 7. \n\nWe thank the referee for their comments that have improved this work. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (Caltech, USA). R.M.L. is funded through a NASA Earth and Space Science Fellowship. E.M.C. gratefully acknowledges NSF CAREER award AST-1351222. We thank J. van den Eijnden for verifying the unabsorbed flux of IGR J17062\u22126143.\n\nPublished - Ludlam_2019_ApJ_873_99.pdf
Submitted - 1902.00520.pdf
",
"abstract": "Atoll sources are accreting neutron star (NS) low-mass X-ray binaries. We present a spectral analysis of four persistent atoll sources (GX 3+1, 4U 1702\u2212429, 4U 0614+091, and 4U 1746\u2212371) observed for ~20 ks each with NuSTAR to determine the extent of the inner accretion disk. These sources range from an apparent luminosity of 0.006\u20130.11 of the Eddington limit (assuming the empirical limit of 3.8 \u00d7 10^(38) erg s^(\u22121)). Broad Fe emission features shaped by Doppler and relativistic effects close to the NS were firmly detected in three of these sources. The position of the disk appears to be close to the innermost stable circular orbit (ISCO) in each case. For GX 3+1, we determine R_(in) = 1.8^(+0.2)_(\u22120.6) R_(ISCO) (90% confidence level) and an inclination of 27\u00b0\u201331\u00b0. For 4U 1702\u2212429, we find a R_(in) = 1.5^(+1.6)_(\u22120.4) R_(ISCO) and inclination of 53\u00b0\u201364\u00b0. For 4U 0614+091, the disk has a position of R_(in) = 1.3^(+5.4)_(\u22120.2) R_(ISCO) and inclination of 50\u00b0\u201362\u00b0. If the disk does not extend to the innermost stable circular orbit, we can place conservative limits on the magnetic field strength in these systems in the event that the disk is truncated at the Alfv\u00e9n radius. This provides the limit at the poles of B \u2264 6.7 \u00d7 10^8 G, 3.3 \u00d7 10^8 G, and 14.5 \u00d7 10^8 G for GX 3+1, 4U 1702\u2212429, and 4U 0614+091, respectively. For 4U 1746\u2212371, we argue that the most plausible explanation for the lack of reflection features is a combination of source geometry and strong Comptonization. We place these sources among the larger sample of NSs that have been observed with NuSTAR.",
"date": "2019-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "873",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 99",
"id_number": "CaltechAUTHORS:20190225-075539902",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190225-075539902",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Earth and Space Science Fellowship"
},
{
"agency": "NSF",
"grant_number": "AST-1351222"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/ab0414",
"primary_object": {
"basename": "1902.00520.pdf",
"url": "https://authors.library.caltech.edu/records/xm1rg-xjj17/files/1902.00520.pdf"
},
"related_objects": [
{
"basename": "Ludlam_2019_ApJ_873_99.pdf",
"url": "https://authors.library.caltech.edu/records/xm1rg-xjj17/files/Ludlam_2019_ApJ_873_99.pdf"
}
],
"pub_year": "2019",
"author_list": "Ludlam, R. M.; Miller, J. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/w4y5v-z5d28",
"eprint_id": 93609,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:42:37",
"lastmod": "2026-03-31 14:06:42",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pearlman-A-B",
"name": {
"family": "Pearlman",
"given": "Aaron B."
},
"orcid": "0000-0002-8912-0732"
},
{
"id": "Coley-J-B",
"name": {
"family": "Coley",
"given": "Joel B."
},
"orcid": "0000-0001-7532-8359"
},
{
"id": "Corbet-R-H-D",
"name": {
"family": "Corbet",
"given": "Robin H. D."
},
"orcid": "0000-0002-3396-651X"
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
}
]
},
"title": "The Orbital Parameters of the Eclipsing High-mass X-Ray Binary Pulsar IGR J16493\u20134348 from Pulsar Timing",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "pulsars: individual (IGR J16493\u20134348) \u2013 stars: neutron \u2013 X-rays: binaries \u2013 X-rays: stars",
"note": "\u00a9 2019. The American Astronomical Society. \n\nReceived 2018 July 11; revised 2018 October 11; accepted 2018 November 9; published 2019 March 7. \n\nWe thank the referee for useful suggestions that helped us improve this paper. A. B. Pearlman acknowledges support by the Department of Defense (DoD) through the National Defense Science and Engineering Graduate (NDSEG) Fellowship Program and by the National Science Foundation (NSF) Graduate Research Fellowship under Grant No. DGE-1144469. This work was partially supported by NASA grant NNX15AI74G.\n\nPublished - Pearlman_2019_ApJ_873_86.pdf
Accepted Version - 1811.06543.pdf
",
"abstract": "IGR J16493\u20134348 is an eclipsing supergiant high-mass X-ray binary (sgHMXB), where accretion onto the compact object occurs via the radially outflowing stellar wind of its early B-type companion. We present an analysis of the system's X-ray variability and periodic modulation using pointed observations (2.5\u201325 keV) and Galactic bulge scans (2\u201310 keV) from the Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA), along with Swift Burst Alert Telescope (BAT) 70-month snapshot (14\u2013195 keV) and transient monitor (15\u201350 keV) observations. The orbital eclipse profiles from the PCA scan and BAT light curves are modeled using asymmetric and symmetric step and ramp functions. We obtain an improved orbital period measurement of 6.7828 \u00b1 0.0004 days from an observed minus calculated (O\u2013C) analysis of mid-eclipse times derived from the BAT transient monitor and PCA scan data. No evidence is found for the presence of a strong photoionization or accretion wake. We refine the superorbital period to 20.067 \u00b1 0.009 days from the discrete Fourier transform (DFT) of the BAT transient monitor light curve. A pulse period of 1093.1036 \u00b1 0.0004 s is measured from a pulsar timing analysis using pointed PCA observations spanning ~1.4 binary orbits. We present pulse times of arrival (ToAs), circular and eccentric timing models, and calculations of the system's Keplerian binary orbital parameters. We derive an X-ray mass function of f_x(M) = 13.2_(-2.5)^(+2.4) M_\u2299 and find a spectral type of B0.5 Ia for the supergiant companion through constraints on the mass and radius of the donor. Measurements of the eclipse half-angle and additional parameters describing the system geometry are provided.",
"date": "2019-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "873",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 86",
"id_number": "CaltechAUTHORS:20190307-081606911",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190307-081606911",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship"
},
{
"agency": "NSF Graduate Research Fellowship",
"grant_number": "DGE-1144469"
},
{
"agency": "NASA",
"grant_number": "NNX15AI74G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aaf001",
"primary_object": {
"basename": "Pearlman_2019_ApJ_873_86.pdf",
"url": "https://authors.library.caltech.edu/records/w4y5v-z5d28/files/Pearlman_2019_ApJ_873_86.pdf"
},
"related_objects": [
{
"basename": "1811.06543.pdf",
"url": "https://authors.library.caltech.edu/records/w4y5v-z5d28/files/1811.06543.pdf"
}
],
"pub_year": "2019",
"author_list": "Pearlman, Aaron B.; Coley, Joel B.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/vwdy6-1ah10",
"eprint_id": 96447,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:38:17",
"lastmod": "2026-03-31 05:59:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Trakhtenbrot-B",
"name": {
"family": "Trakhtenbrot",
"given": "Benny"
},
"orcid": "0000-0002-3683-7297"
},
{
"id": "Arcavi-I",
"name": {
"family": "Arcavi",
"given": "Iair"
},
"orcid": "0000-0001-7090-4898"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Tacchella-S",
"name": {
"family": "Tacchella",
"given": "Sandro"
},
"orcid": "0000-0002-8224-4505"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Netzer-H",
"name": {
"family": "Netzer",
"given": "Hagai"
}
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "Peter G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Horesh-A",
"name": {
"family": "Horesh",
"given": "Assaf"
},
"orcid": "0000-0002-5936-1156"
},
{
"id": "Mej\u00eda-Restrepo-J-E",
"name": {
"family": "Mej\u00eda-Restrepo",
"given": "Juli\u00e1n Esteban"
},
"orcid": "0000-0001-8450-7463"
},
{
"id": "Hosseinzadeh-G",
"name": {
"family": "Hosseinzadeh",
"given": "Griffin"
},
"orcid": "0000-0002-0832-2974"
},
{
"id": "Hallefors-V",
"name": {
"family": "Hallefors",
"given": "Valentina"
}
},
{
"id": "Howell-D-A",
"name": {
"family": "Howell",
"given": "D. Andrew"
},
"orcid": "0000-0003-4253-656X"
},
{
"id": "McCully-C",
"name": {
"family": "McCully",
"given": "Curtis"
},
"orcid": "0000-0001-5807-7893"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "Marianne"
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Kamraj-N",
"name": {
"family": "Kamraj",
"given": "Nikita"
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Lansbury-G-B",
"name": {
"family": "Lansbury",
"given": "George Benjamin"
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Wyrzykowski-\u0141",
"name": {
"family": "Wyrzykowski",
"given": "\u0141ukasz"
}
},
{
"id": "Gromadzki-M",
"name": {
"family": "Gromadzki",
"given": "Mariusz"
},
"orcid": "0000-0002-1650-1518"
},
{
"id": "Hamanowicz-A",
"name": {
"family": "Hamanowicz",
"given": "Aleksandra"
}
},
{
"id": "Cenko-S-B",
"name": {
"family": "Cenko",
"given": "S. Bradley"
},
"orcid": "0000-0003-1673-970X"
},
{
"id": "Sand-D-J",
"name": {
"family": "Sand",
"given": "David J."
},
"orcid": "0000-0003-4102-380X"
},
{
"id": "Hsiao-Eric-Y-Astro",
"name": {
"family": "Hsiao",
"given": "Eric Y."
}
},
{
"id": "Phillips-M-M",
"name": {
"family": "Phillips",
"given": "Mark M."
},
"orcid": "0000-0003-2734-0796"
},
{
"id": "Diamond-T-R",
"name": {
"family": "Diamond",
"given": "Tiara R."
}
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Gendreau-K-C",
"name": {
"family": "Gendreau",
"given": "Keith C."
}
},
{
"id": "Arzoumanian-Z",
"name": {
"family": "Arzoumanian",
"given": "Zaven"
}
},
{
"id": "Remillard-R-A",
"name": {
"family": "Remillard",
"given": "Ron"
},
"orcid": "0000-0003-4815-0481"
}
]
},
"title": "A new class of flares from accreting supermassive black holes",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2019. \n\nReceived: 23 November 2017; Accepted: 21 November 2018; Published online: 14 January 2019. \n\nB.T. is a Zwicky Fellow. I.A. is an Einstein Fellow. E.K. is a Hubble Fellow. We thank N. Caplar, J. Guillochon, Z. Haiman, E. Lusso, and K. Schawinski for useful discussions. We thank C. Tadhunter for providing the spectrum of the F01004-2237 transient and his helpful comments. Part of this work was inspired by discussions within International Team #371, 'Using Tidal Disruption Events to Study Super-Massive Black Holes', hosted at the International Space Science Institute in Bern, Switzerland. We thank all the participants of the team meeting for their beneficial comments. Support for I.A. was provided by NASA through the Einstein Fellowship Program, grant PF6-170148. C.R. acknowledges support from the CONICYT\u2009+\u2009PAI Convocatoria Nacional subvencion a instalacion en la academia convocatoria a no 2017 PAI77170080. P.G.J. acknowledges support from European Research Council Consolidator Grant 647208. A. Horesh acknowledges support by the I-Core Program of the Planning and Budgeting Committee and the Israel Science Foundation. G.H., D.A.H. and C.M. acknowledge support from NSF grant AST-1313484. M.B. acknowledges support from the Black Hole Initiative at Harvard University, which is funded by a grant from the John Templeton Foundation. G.L. acknowledges support from a Herchel Smith Research Fellowship of the University of Cambridge. \u0141.W., M.G. and A. Hamanowicz acknowledge Polish National Science Centre grant OPUS no 2015/17/B/ST9/03167 to \u0141.W. Research by D.J.S. is supported by NSF grants AST-1412504 and AST-1517649. E.Y.H. acknowledges the support provided by the National Science Foundation under Grant No. AST-1613472 and by the Florida Space Grant Consortium. This work makes use of observations from the Las Cumbres Observatory network. This publication also makes use of data products from the Wide-field Infrared Survey Explorer. WISE and NEOWISE are funded by the National Aeronautics and Space Administration. \n\nThis work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR operations, software and calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nWe thank the Swift, NuSTAR and NICER teams for scheduling and performing the target-of-opportunity observations presented here on short notice. The LRIS spectrum presented herein was obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The observatory was made possible by the generous financial support of the W. M. Keck Foundation. We recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. \n\nThese results made use of the Discovery Channel Telescope (DCT) at Lowell Observatory. Lowell is a private, non-profit institution dedicated to astrophysical research and public appreciation of astronomy and operates the DCT in partnership with Boston University, the University of Maryland, the University of Toledo, Northern Arizona University and Yale University. The upgrade of the DeVeny optical spectrograph has been funded by a generous grant from John and Ginger Giovale. \n\nThe FLAMINGOS-2 spectrum was obtained at the Gemini Observatory under program GS-2017A-Q-33 (PI: Sand), which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the National Science Foundation (USA), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n Productiva (Argentina) and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00e3o (Brazil). \n\nAuthor Contributions: B.T. and I.A. led the data collection, analysis and interpretation, as well as the manuscript preparation. C.R. performed the analysis and modelling of archival and new X-ray data. S.T. performed the morphological and SED modelling of the host galaxy. D.S., M.B., M.H., N.K. and G.B.L. took part in obtaining and calibrating the Palomar and Keck spectra. H.N. contributed to the identification and interpretation of the Bowen fluorescence spectral features. P.G.J. and A. Horesh contributed to the interpretation of multi-wavelength data and to pursuing follow-up observations. J.E.M.-R. contributed to the analysis of optical spectra. G.H., V.H. and C.M. contributed to collecting, calibrating and analysing the Las Cumbres Observatory and Swift/UVOT data. D.A.H. helped schedule and monitor the data from the Las Cumbres Observatory. \u0141.W., M.G. and A. Hamanowicz contributed to NIR line identification and provided the optical spectrum of OGLE17aaj. S.B.C. provided the the DCT spectrum. D.J.S. provided the the Gemini-South/FLAMINGOS-2 NIR spectrum. E.Y.H., M.M.P. and T.R.D. provided the Magellan/FIRE NIR spectrum. E.K. contributed to the X-ray data analysis and interpretation. K.C.G., Z.A. and R.R. contributed to the NICER data acquisition and calibration. \n\nData availability: The data that support the findings of this study are available from the corresponding author upon reasonable request. All of our spectra are publicly available on the Weizmann Interactive Supernova data REPository (WISeREP). The data used to prepare Supplementary Fig. 1 are available from the ASAS-SN Light Curve Server (https://asas-sn.osu.edu/). \n\nThe authors declare no competing interests.\n\nAccepted Version - 1901.03731.pdf
Supplemental Material - 41550_2018_661_MOESM1_ESM.pdf
",
"abstract": "Accreting supermassive black holes (SMBHs) can exhibit variable emission across the electromagnetic spectrum and over a broad range of timescales. The variability of active galactic nuclei (AGNs) in the ultraviolet and optical is usually at the few tens of per cent level over timescales of hours to weeks. Recently, rare, more dramatic changes to the emission from accreting SMBHs have been observed, including tidal disruption events, 'changing look' AGNs and other extreme variability objects. The physics behind the 're-ignition', enhancement and 'shut-down' of accretion onto SMBHs is not entirely understood. Here we present a rapid increase in ultraviolet\u2013optical emission in the centre of a nearby galaxy, marking the onset of sudden increased accretion onto a SMBH. The optical spectrum of this flare, dubbed AT 2017bgt, exhibits a mix of emission features. Some are typical of luminous, unobscured AGNs, but others are likely driven by Bowen fluorescence\u2014robustly linked here with high-velocity gas in the vicinity of the accreting SMBH. The spectral features and increased ultraviolet flux show little evolution over a period of at least 14 months. This disfavours the tidal disruption of a star as their origin, and instead suggests a longer-term event of intensified accretion. Together with two other recently reported events with similar properties, we define a new class of SMBH-related flares. This has important implications for the classification of different types of enhanced accretion onto SMBHs.",
"date": "2019-03",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "3",
"number": "3",
"publisher": "Nature Publishing Group",
"pagerange": "242-250",
"id_number": "CaltechAUTHORS:20190614-111557235",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190614-111557235",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "ETH Zurich"
},
{
"agency": "NASA Einstein Fellowship",
"grant_number": "PF6-170148"
},
{
"agency": "NASA Hubble Fellowship"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "2017 PAI77170080"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "I-CORE Program of the Planning and Budgeting Committee"
},
{
"agency": "Israel Science Foundation"
},
{
"agency": "NSF",
"grant_number": "AST-1313484"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "University of Cambridge"
},
{
"agency": "OPUS Program",
"grant_number": "2015/17/B/ST9/03167"
},
{
"agency": "NSF",
"grant_number": "AST-1412504"
},
{
"agency": "NSF",
"grant_number": "AST-1517649"
},
{
"agency": "NSF",
"grant_number": "AST-1613472"
},
{
"agency": "Florida Space Grant Consortium"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "John and Ginger Giovale"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1038/s41550-018-0661-3",
"primary_object": {
"basename": "1901.03731.pdf",
"url": "https://authors.library.caltech.edu/records/vwdy6-1ah10/files/1901.03731.pdf"
},
"related_objects": [
{
"basename": "41550_2018_661_MOESM1_ESM.pdf",
"url": "https://authors.library.caltech.edu/records/vwdy6-1ah10/files/41550_2018_661_MOESM1_ESM.pdf"
}
],
"pub_year": "2019",
"author_list": "Trakhtenbrot, Benny; Arcavi, Iair; et al."
},
{
"id": "https://authors.library.caltech.edu/records/swfqw-mq584",
"eprint_id": 92711,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:16:42",
"lastmod": "2026-03-31 00:10:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Marchesi-S",
"name": {
"family": "Marchesi",
"given": "S."
},
"orcid": "0000-0001-5544-0749"
},
{
"id": "Ajello-M",
"name": {
"family": "Ajello",
"given": "M."
},
"orcid": "0000-0002-6584-1703"
},
{
"id": "Zhao-X",
"name": {
"family": "Zhao",
"given": "X."
}
},
{
"id": "Marcotulli-L",
"name": {
"family": "Marcotulli",
"given": "L."
}
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Comastri-A",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Cusumano-G",
"name": {
"family": "Cusumano",
"given": "G."
}
},
{
"id": "Lanzuisi-G",
"name": {
"family": "Lanzuisi",
"given": "G."
},
"orcid": "0000-0001-9094-0984"
},
{
"id": "La-Parola-V",
"name": {
"family": "La Parola",
"given": "V."
},
"orcid": "0000-0002-8087-6488"
},
{
"id": "Segreto-A",
"name": {
"family": "Segreto",
"given": "A."
}
},
{
"id": "Vignali-C",
"name": {
"family": "Vignali",
"given": "C."
},
"orcid": "0000-0002-8853-9611"
}
]
},
"title": "Compton-thick AGNs in the NuSTAR Era. III. A Systematic Study of the Torus Covering Factor",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: nuclei \u2013 X-rays: galaxies",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 July 15; revised 2018 November 23; accepted 2018 December 20; published 2019 February 6. \n\nWe thank an anonymous referee for the useful comments, which helped in improving the paper. \n\nS.M., M.A., and X.Z. acknowledge funding under NASA contract 80NSSC17K0635. Mi.Ba. acknowledges support from the Black Hole Initiative at Harvard University, which is funded by a grant from the John Templeton Foundation. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester, as well as of the TOPCAT software (Taylor 2005) for the analysis of data tables.\n\nPublished - Marchesi_2019_ApJ_872_8.pdf
Accepted Version - 1812.09217.pdf
",
"abstract": "We present the analysis of a sample of 35 candidate Compton-thick active galactic nuclei (AGNs) selected in the nearby universe (average redshift \u3008z\u3009 ~ 0.03) with the Swift-BAT 100-month survey. All sources have available NuSTAR data, thus allowing us to constrain with unprecedented quality important spectral parameters such as the obscuring torus line-of-sight column density (N_(H,z)), the average torus column density (N H,tor), and the torus covering factor (f_c ). We compare the best-fit results obtained with the widely used MYTorus (Murphy & Yaqoob 2009) model with those of the recently published borus02 model (Balokovi\u0107 et al. 2018) used in the same geometrical configuration of MYTorus (i.e., with f_c = 0.5). We find a remarkable agreement between the two, although with increasing dispersion in N_(H,z) moving toward higher column densities. We then use borus02 to measure f_c . High-f c sources have, on average, smaller offset between N_(H,z) and N_(H,tor) than low-f_c ones. Therefore, low f c values can be linked to a \"patchy torus\" scenario, where the AGN is seen through an overdense region in the torus, while high-f c objects are more likely to be obscured by a more uniform gas distribution. Finally, we find potential evidence of an inverse trend between f c and the AGN 2\u201310 keV luminosity, i.e., sources with higher f c values have on average lower luminosities.",
"date": "2019-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "872",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 8",
"id_number": "CaltechAUTHORS:20190206-100219625",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190206-100219625",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "80NSSC17K0635"
},
{
"agency": "Harvard University"
},
{
"agency": "John Templeton Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aafbeb",
"primary_object": {
"basename": "1812.09217.pdf",
"url": "https://authors.library.caltech.edu/records/swfqw-mq584/files/1812.09217.pdf"
},
"related_objects": [
{
"basename": "Marchesi_2019_ApJ_872_8.pdf",
"url": "https://authors.library.caltech.edu/records/swfqw-mq584/files/Marchesi_2019_ApJ_872_8.pdf"
}
],
"pub_year": "2019",
"author_list": "Marchesi, S.; Ajello, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/j4bnz-h8464",
"eprint_id": 98680,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:15:59",
"lastmod": "2025-06-30 18:18:50",
"type": "publication_whitepaper",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Fryer-C-L",
"name": {
"family": "Fryer",
"given": "Chris L."
},
"orcid": "0000-0003-2624-0056"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin"
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Catching Element Formation In The Act - The Case for a New MeV Gamma-Ray Mission: Radionuclide Astronomy in the 2020s",
"ispublished": "unpub",
"full_text_status": "public",
"note": "A White Paper for the 2020 Decadal Survey.\n\nSubmitted - 1902.02915.pdf
",
"abstract": "Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects and phenomena: stars, supernovae, novae, neutron stars, stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays and relativistic-particle acceleration, and the evolution of galaxies. MeV gamma-rays provide a unique probe of nuclear processes in astronomy, directly measuring radioactive decay, nuclear de-excitation, and positron annihilation. The substantial information carried by gamma-ray photons allows us to see deeper into these objects, the bulk of the power is often emitted at gamma-ray energies, and radioactivity provides a natural physical clock that adds unique information. New science will be driven by time-domain population studies at gamma-ray energies. This science is enabled by next-generation gamma-ray instruments with one to two orders of magnitude better sensitivity, larger sky coverage, and faster cadence than all previous gamma-ray instruments. This transformative capability permits: (a) the accurate identification of the gamma-ray emitting objects and correlations with observations taken at other wavelengths and with other messengers; (b) construction of new gamma-ray maps of the Milky Way and other nearby galaxies where extended regions are distinguished from point sources; and (c) considerable serendipitous science of scarce events -- nearby neutron star mergers, for example. Advances in technology push the performance of new gamma-ray instruments to address a wide set of astrophysical questions.",
"date": "2019-02-08",
"date_type": "published",
"id_number": "CaltechAUTHORS:20190917-133401954",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-133401954",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.48550/arXiv.1902.02915",
"primary_object": {
"basename": "1902.02915.pdf",
"url": "https://authors.library.caltech.edu/records/j4bnz-h8464/files/1902.02915.pdf"
},
"pub_year": "2019",
"author_list": "Fryer, Chris L.; Grefenstette, Brian; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ce2ja-w1524",
"eprint_id": 92620,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:12:43",
"lastmod": "2026-03-31 14:15:27",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Searching for the Donor Stars of ULX Pulsars",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "infrared: stars \u2013 stars: neutron \u2013 X-rays: individual (M82 X-2, NGC 5907 X-1, NGC 5907 ULX-2)",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 October 2; revised 2018 December 18; accepted 2018 December 19; published 2019 February 4. \n\nWe would like to thank the anonymous referee whose comments helped to significantly improve the paper. \n\nThis work is based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program 15074. Support for Program number 15074 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS 5-26555. The scientific results reported in this article are based in part on data obtained from the Chandra Data Archive. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. The work of DS was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. \n\nFacilities: HST (WFPC2 and WFC3) - , Chandra (ACIS) - , Gaia - . \n\nSoftware: astropy (Astropy Collaboration et al. 2013), DOLPHOT (Dolphin 2000), MESA (Paxton et al. 2011, 2013, 2015), CIAO (Fruscione et al. 2006).\n\nPublished - Heida_2019_ApJ_871_231.pdf
Accepted Version - 1901.03776.pdf
",
"abstract": "We report on our search for the optical counterparts of two ultraluminous X-ray pulsars with known orbital periods, M82 X-2 and NGC 5907 X-1, in new and archival Hubble Space Telescope observations, in an effort to characterize the donor stars in these systems. We detect five near-infrared sources consistent with the position of M82 X-2 that are too bright to be single stars. We also detect seven sources in the WFC3/UVIS F336W image whose photometry matches that of 10\u201315 M \u2299 stars turning off the main sequence. Such stars have densities consistent with the properties of the donor star of M82 X-2 as inferred from X-ray timing analysis, although it is also possible that the donor is a lower-mass star below our detection limit or that there is a significant contribution from the accretion disk to the optical emission. We detect three candidate counterparts to NGC 5907 X-1 in the near-infrared. All of these are too bright to be the donor star of the ultraluminous X-ray source (ULX), which, based on its orbital period, is a red giant. The high background at the location of NGC 5907 X-1 precludes us from detecting this expected donor star. The recently discovered NGC 5907 ULX-2 also falls within the field of view of the near-infrared imaging; we detect four sources in the error circle, with photometry that matches asymptotic giant branch stars. The star suggested to be the counterpart of NGC 5907 ULX-2 by Pintore et al. falls outside our 2\u03c3 error circle.",
"date": "2019-02-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "871",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 231",
"id_number": "CaltechAUTHORS:20190204-095332991",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190204-095332991",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NAS 5-26555"
},
{
"agency": "Gaia Multilateral Agreement"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aafa77",
"primary_object": {
"basename": "1901.03776.pdf",
"url": "https://authors.library.caltech.edu/records/ce2ja-w1524/files/1901.03776.pdf"
},
"related_objects": [
{
"basename": "Heida_2019_ApJ_871_231.pdf",
"url": "https://authors.library.caltech.edu/records/ce2ja-w1524/files/Heida_2019_ApJ_871_231.pdf"
}
],
"pub_year": "2019",
"author_list": "Heida, M.; Harrison, F. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6efdy-91e51",
"eprint_id": 98432,
"eprint_status": "archive",
"datestamp": "2023-08-19 14:10:23",
"lastmod": "2026-03-31 13:24:31",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Schartel-N",
"name": {
"family": "Schartel",
"given": "N."
}
},
{
"id": "Grupe-D",
"name": {
"family": "Grupe",
"given": "D."
},
"orcid": "0000-0002-9961-3661"
},
{
"id": "Komossa-S",
"name": {
"family": "Komossa",
"given": "S."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kollatschny-W",
"name": {
"family": "Kollatschny",
"given": "W."
}
},
{
"id": "Mikula-R",
"name": {
"family": "Mikula",
"given": "R."
}
},
{
"id": "Santos-Lle\u00f3-M",
"name": {
"family": "Santos-Lle\u00f3",
"given": "M."
}
},
{
"id": "Tom\u00e1s-L",
"name": {
"family": "Tom\u00e1s",
"given": "L."
}
}
]
},
"title": "X-ray spectra reveal the reawakening of the repeat changing-look AGN NGC 1566",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, galaxies: active, galaxies: individual: NGC 1566, galaxies: Seyfert",
"note": "\u00a9 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). \n\nAccepted 2018 November 23. Received 2018 November 13; in original form 2018 October 19. Published: 27 November 2018. \n\nMLP is supported by an ESA Research Fellowship. We thank the anonymous referee for detailed and constructive feedback. We thank J. Lewis for editing the manuscript. Based on observations obtained with XMM\u2013Newton, an ESA science mission funded by ESA Member States and NASA, and the NuSTAR mission, a project led by Caltech, managed by JPL, and funded by NASA. This work has been supported by the Deutsche Forschungsgemeinschaft (DFG) grant Ko 857/33-1. We thank the Swift team for carrying out our ToO requests.\n\nPublished - sly224.pdf
Accepted Version - 1811.10289.pdf
",
"abstract": "We present simultaneous XMM\u2013Newton and NuSTAR observations of the repeat changing-look AGN NGC 1566, which dramatically increased in brightness in the IR to X-ray bands in 2018. The broad-band X-ray spectrum was taken at the peak of the outburst and is typical of Seyfert 1 AGN. The spectrum shows a soft excess, Compton hump, warm absorption and reflection, ruling out tidal disruption as the cause of the outburst and demonstrating that a 'standard' accretion disk can develop very rapidly. The high-resolution grating spectrum reveals that the outburst has launched a \u223c500\u2009km s^(\u22121) outflow, and shows photoionized emission lines from rest-frame gas. We discuss possible mechanisms for the outburst, and conclude that it is most likely caused by a disk instability.",
"date": "2019-02",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society: Letters",
"volume": "483",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "L88-L92",
"id_number": "CaltechAUTHORS:20190905-110449716",
"issn": "1745-3925",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190905-110449716",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "857/33-1"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnrasl/sly224",
"primary_object": {
"basename": "1811.10289.pdf",
"url": "https://authors.library.caltech.edu/records/6efdy-91e51/files/1811.10289.pdf"
},
"related_objects": [
{
"basename": "sly224.pdf",
"url": "https://authors.library.caltech.edu/records/6efdy-91e51/files/sly224.pdf"
}
],
"pub_year": "2019",
"author_list": "Parker, M. L.; Schartel, N.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/m8vy1-48w82",
"eprint_id": 92453,
"eprint_status": "archive",
"datestamp": "2023-08-19 13:57:20",
"lastmod": "2026-03-31 05:43:52",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "Erin"
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic"
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Beuchert-T",
"name": {
"family": "Beuchert",
"given": "Tobias"
}
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Gatuzz-E",
"name": {
"family": "Gatuzz",
"given": "Efrain"
},
"orcid": "0000-0002-3252-9633"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "Mislav"
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Tombesi-F",
"name": {
"family": "Tombesi",
"given": "Francesco"
},
"orcid": "0000-0002-6562-8654"
},
{
"id": "Connors-R-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "Kallman-Timothy-R",
"name": {
"family": "Kallman",
"given": "Timothy R."
},
"orcid": "0000-0002-5779-6906"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Lanz-L",
"name": {
"family": "Lanz",
"given": "Lauranne"
},
"orcid": "0000-0002-3249-8224"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "David R."
},
"orcid": "0000-0001-8128-6976"
}
]
},
"title": "Implications of the Warm Corona and Relativistic Reflection Models for the Soft Excess in Mrk 509",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 black hole physics \u2013 galaxies: active \u2013 galaxies: individual (Mrk 509) \u2013 galaxies: nuclei",
"note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2018 September 24; revised 2018 November 26; accepted 2018 December 7; published 2019 January 24. \n\nWe thank P.O. Petrucci, J. Malzac, B. Czerny, A. R\u00f3\u017ca\u0144ska, C. Done, and the members of the FERO collaboration for insightful discussions that promoted many aspects of this paper. We also thank F. Ursini for comments that improved the manuscript. \n\nJ.A.G. acknowledges support from NASA grant NNX15AV31G and the Alexander von Humboldt Foundation. R.M.T.C. has been supported by NASA grant 80NSSC177K0515. M.B. acknowledges support from the black hole initiative at Harvard University, which is funded by a grant from the John Templeton Foundation. J.F.S. has been supported by NASA Einstein Fellowship grant PF5-160144. F.T. acknowledges support by the Programma per Giovani Ricercatori\u2014anno 2014 \"Rita Levi Montalcini.\" L.L. acknowledges support from NASA through grant No. NNX15AP24G C.R. acknowledges support from the CONICYT+PAI Convocatoria Nacional subvenci\u00f3n a instalaci\u00f3n en la academia convocatoria a\u00f1o 2017 PAI77170080. \n\nThis work was partially supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Suzaku (XIS) - . \n\nSoftware: xspec (v12.9.0d; Arnaud 1996), MYtorus (Murphy & Yaqoob 2009), borus02 (Balokovi\u0107 et al. 2018), xillver (Garc\u00eda & Kallman 2010; Garc\u00eda et al. 2013), relxill (v1.2.0; Garc\u00eda et al. 2014; Dauser et al. 2014), xstar (v2.41; Kallman & Bautista 2001), nustardas (v1.6.0).\n\nPublished - Garc\u00eda_2019_ApJ_871_88.pdf
Accepted Version - 1812.03194.pdf
",
"abstract": "We present the analysis of the first Nuclear Spectroscopic Telescope Array observations (~220 ks), simultaneous with the last Suzaku observations (~50 ks), of the active galactic nucleus of the bright Seyfert 1 galaxy Mrk 509. The time-averaged spectrum in the 1\u201379 keV X-ray band is dominated by a power-law continuum (\u0393 ~ 1.8\u20131.9), a strong soft excess around 1 keV, and signatures of X-ray reflection in the form of Fe K emission (~6.4 keV), an Fe K absorption edge (~7.1 keV), and a Compton hump due to electron scattering (~20\u201330 keV). We show that these data can be described by two very different prescriptions for the soft excess: a warm (kT ~ 0.5\u20131 keV) and optically thick (\u03c4 ~ 10\u201320) Comptonizing corona or a relativistically blurred ionized reflection spectrum from the inner regions of the accretion disk. While these two scenarios cannot be distinguished based on their fit statistics, we argue that the parameters required by the warm corona model are physically incompatible with the conditions of standard coronae. Detailed photoionization calculations show that even in the most favorable conditions, the warm corona should produce strong absorption in the observed spectrum. On the other hand, while the relativistic reflection model provides a satisfactory description of the data, it also requires extreme parameters, such as maximum black hole spin, a very low and compact hot corona, and a very high density for the inner accretion disk. Deeper observations of this source are thus necessary to confirm the presence of relativistic reflection and further understand the nature of its soft excess.",
"date": "2019-01-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "871",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 88",
"id_number": "CaltechAUTHORS:20190124-112047031",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190124-112047031",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX15AV31G"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "NASA Einstein Fellowship",
"grant_number": "PF5-160144"
},
{
"agency": "Programma per Giovani Ricercatori",
"grant_number": "anno 2014"
},
{
"agency": "NASA",
"grant_number": "NNX15AP24G"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "PAI77170080"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aaf739",
"primary_object": {
"basename": "1812.03194.pdf",
"url": "https://authors.library.caltech.edu/records/m8vy1-48w82/files/1812.03194.pdf"
},
"related_objects": [
{
"basename": "Garc\u00eda_2019_ApJ_871_88.pdf",
"url": "https://authors.library.caltech.edu/records/m8vy1-48w82/files/Garc\u00eda_2019_ApJ_871_88.pdf"
}
],
"pub_year": "2019",
"author_list": "Garc\u00eda, Javier A.; Kara, Erin; et al."
},
{
"id": "https://authors.library.caltech.edu/records/epwf1-62d41",
"eprint_id": 92331,
"eprint_status": "archive",
"datestamp": "2023-08-22 00:41:51",
"lastmod": "2026-03-31 16:16:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "L\u00f3pez-K-M",
"name": {
"family": "L\u00f3pez",
"given": "K. M."
}
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Rau-A",
"name": {
"family": "Rau",
"given": "A."
},
"orcid": "0000-0001-5990-6243"
},
{
"id": "Steeghs-D-T-H",
"name": {
"family": "Steeghs",
"given": "D."
}
}
]
},
"title": "Quiescent NIR and optical counterparts to candidate black hole X-ray binaries",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: black holes \u2013 infrared: stars \u2013 X-rays: individual: XTE J1818\u2212245; IGR\nJ17451\u22123022; XTE J1726\u2212476; XTE J2012+381; XTE J1752\u2212223; MAXI J1543\u2212564",
"note": "\u00a9 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.\nThis article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model).\n\nAccepted 2018 October 12. Received 2018 October 12; in original form 2018 August 7. Published: 16 October 2018.\n\nThis study is based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programmes 099.A-9025(A) and 1101.D-0105(A). PGJ and KML acknowledge funding from the European Research Council under ERC Consolidator Grant agreement no 647208. Part of the funding for GROND (both hardware as well as personnel) was generously granted from the Deutsche Forschungsgemeinschaft Gottfried Wilhelm Leibniz Prize to Prof. G. Hasinger (DFG grant HA 1850/28-1). MAPT acknowledges support via a Ram\u00f3n y Cajal Fellowship (RYC-2015-17854). MAPT also acknowledges support by the Spanish Ministry of Economy, Industry and Competitiveness under grant AYA2017-83216-P. This research is based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof\u00edsica de Canarias; with the Keck Telescope at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. We have made use of the SIMBAD data base, operated at CDS, Strasbourg, France, of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.\n\nPublished - sty2793.pdf
Accepted Version - 1810.06070.pdf
",
"abstract": "We present near-infrared and optical imaging of 15 candidate black hole X-ray binaries. In addition to quiescent observations for all sources, we also observed two of these sources (IGR J17451\u22123022 and XTE J1818\u2212245) in outburst. We detect the quiescent counterpart for 12 out of 15 sources, and for the remaining 3, we report limiting magnitudes. The magnitudes of the detected counterparts range between K_s = 17.59 and K_s = 22.29 mag. We provide (limits on) the absolute magnitudes and finding charts of all sources. Of these 12 detections in quiescence, 7 detections represent the first quiescent reported values (for MAXI J1543\u2212564, XTE J1726\u2212476, IGR J17451\u22123022, XTE J1818\u2212245, MAXI J1828\u2212249, MAXI J1836\u2212194, Swift J1910.2\u22120546), and 2 detections show fainter counterparts to XTE J1752\u2212223 and XTE J2012+381 than previously reported. We used theoretical arguments and observed trends, for instance between the outburst and quiescent X-ray luminosity and orbital period P_(orb) to derive an expected trend between \u0394K_s and P_(orb) of \u0394K_s \u221d log P^(0.565)_(orb)\u2060. Comparing this to observations, we find a different behaviour. We discuss possible explanations for this result.",
"date": "2019-01-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "482",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2149-2165",
"id_number": "CaltechAUTHORS:20190117-074855191",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190117-074855191",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "HA 1850/28-1"
},
{
"agency": "Ram\u00f3n y Cajal Fellowship",
"grant_number": "RYC-2015-17854"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2017-83216-P"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/sty2793",
"primary_object": {
"basename": "1810.06070.pdf",
"url": "https://authors.library.caltech.edu/records/epwf1-62d41/files/1810.06070.pdf"
},
"related_objects": [
{
"basename": "sty2793.pdf",
"url": "https://authors.library.caltech.edu/records/epwf1-62d41/files/sty2793.pdf"
}
],
"pub_year": "2019",
"author_list": "L\u00f3pez, K. M.; Jonker, P. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/561ys-ycf54",
"eprint_id": 90369,
"eprint_status": "archive",
"datestamp": "2023-08-22 00:24:07",
"lastmod": "2023-10-18 23:24:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "McComas-David-J",
"name": {
"family": "McComas",
"given": "D. J."
},
"orcid": "0000-0001-6160-1158"
},
{
"id": "Cohen-Christina-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Leske-Richard-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
}
]
},
"title": "Interstellar Mapping and Acceleration Probe (IMAP): A New NASA Mission",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliosphere; Interstellar medium; IBEX; IMAP; ENA; Energetic particle",
"note": "\u00a9 2018 The Author(s). This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. \n\nReceived: 11 September 2018; Accepted: 5 October 2018; First Online: 22 October 2018. \n\nWe are deeply indebted to all the other outstanding IMAP team members at all of our institutions that supported our proposal and continue to support development of this revolutionary mission. We also thank NASA and their review teams for their careful evaluation of our proposal in response to AO NNH17ZDA007O, as well as supporting the publication of this paper.\n\nPublished - McComas2018_Article_InterstellarMappingAndAccelera.pdf
Supplemental Material - 11214_2018_550_MOESM1_ESM.eps
",
"abstract": "The Interstellar Mapping and Acceleration Probe (IMAP) is a revolutionary mission that simultaneously investigates two of the most important overarching issues in Heliophysics today: the acceleration of energetic particles and interaction of the solar wind with the local interstellar medium. While seemingly disparate, these are intimately coupled because particles accelerated in the inner heliosphere play critical roles in the outer heliospheric interaction. Selected by NASA in 2018, IMAP is planned to launch in 2024. The IMAP spacecraft is a simple sun-pointed spinner in orbit about the Sun-Earth L1 point. IMAP's ten instruments provide a complete and synergistic set of observations to simultaneously dissect the particle injection and acceleration processes at 1 AU while remotely probing the global heliospheric interaction and its response to particle populations generated by these processes. In situ at 1 AU, IMAP provides detailed observations of solar wind electrons and ions; suprathermal, pickup, and energetic ions; and the interplanetary magnetic field. For the outer heliosphere interaction, IMAP provides advanced global observations of the remote plasma and energetic ions over a broad energy range via energetic neutral atom imaging, and precise observations of interstellar neutral atoms penetrating the heliosphere. Complementary observations of interstellar dust and the ultraviolet glow of interstellar neutrals further deepen the physical understanding from IMAP. IMAP also continuously broadcasts vital real-time space weather observations. Finally, IMAP engages the broader Heliophysics community through a variety of innovative opportunities. This paper summarizes the IMAP mission at the start of Phase A development.",
"date": "2018-12",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "214",
"number": "12",
"publisher": "Springer",
"pagerange": "Art. No. 116",
"id_number": "CaltechAUTHORS:20181023-130433363",
"issn": "0038-6308",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181023-130433363",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1007/s11214-018-0550-1",
"primary_object": {
"basename": "11214_2018_550_MOESM1_ESM.eps",
"url": "https://authors.library.caltech.edu/records/561ys-ycf54/files/11214_2018_550_MOESM1_ESM.eps"
},
"related_objects": [
{
"basename": "McComas2018_Article_InterstellarMappingAndAccelera.pdf",
"url": "https://authors.library.caltech.edu/records/561ys-ycf54/files/McComas2018_Article_InterstellarMappingAndAccelera.pdf"
}
],
"pub_year": "2018",
"author_list": "McComas, D. J.; Cohen, C. M. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ehwb0-9t616",
"eprint_id": 92017,
"eprint_status": "archive",
"datestamp": "2023-08-19 13:02:27",
"lastmod": "2026-04-01 03:04:55",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Falkner-S",
"name": {
"family": "Falkner",
"given": "S."
},
"orcid": "0000-0001-5209-991X"
},
{
"id": "Marcu-Cheatham-D-M",
"name": {
"family": "Marcu-Cheatham",
"given": "D."
},
"orcid": "0000-0001-8061-611X"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "J."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "K."
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Natalucci-L",
"name": {
"family": "Natalucci",
"given": "L."
},
"orcid": "0000-0002-6601-9543"
},
{
"id": "Kretschmar-P",
"name": {
"family": "Kretschmar",
"given": "P."
},
"orcid": "0000-0001-9840-2048"
}
]
},
"title": "Multiple cyclotron line-forming regions in GX 301\u22122",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks / magnetic fields / X-rays: binaries / stars: neutron / pulsars: individual: GX 301-2",
"note": "\u00a9 ESO 2018. \n\nReceived 19 October 2017 / Accepted 13 September 2018. \n\nWe thank the referee for their helpful comments. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We would like to thank John E. Davis for the slxfig module, which was used to produce all figures in this work. The Swift/BAT transient monitor results were provided by the Swift/BAT team. This research has made use of data obtained from the Suzaku satellite, a collaborative mission between the space agencies of Japan (JAXA) and the USA (NASA). L.N. acknowledges support by ASI/INAF grant I/037/12/0 and PRIN-INAF 2014 grant \"Towards a unified picture of accretion in High Mass X-Ray Binaries\".\n\nPublished - aa32132-17.pdf
Accepted Version - 1809.05691.pdf
",
"abstract": "We present two observations of the high-mass X-ray binary GX 301\u22122 with NuSTAR, taken at different orbital phases and different luminosities. We find that the continuum is well described by typical phenomenological models, like a very strongly absorbed NPEX model. However, for a statistically acceptable description of the hard X-ray spectrum we require two cyclotron resonant scattering features (CRSF), one at \u223c35 keV and the other at \u223c50 keV. Even though both features strongly overlap, the good resolution and sensitivity of NuSTAR allows us to disentangle them at \u226599.9% significance. This is the first time that two CRSFs have been seen in GX 301\u22122. We find that the CRSFs are very likely independently formed, as their energies are not harmonically related and, if the observed feature were due to a single line, the deviation from a Gaussian shape would be very large. We compare our results to archival Suzaku data and find that our model also provides a good fit to those data. We study the behavior of the continuum as well as the CRSF parameters as function of pulse phase in seven phase bins. We find that the energy of the 35 keV CRSF varies smoothly as a function of phase, between 30 and 38 keV. To explain this variation, we apply a simple model of the accretion column, taking into account the altitude of the line-forming region, the velocity of the in-falling material, and the resulting relativistic effects. We find that in this model the observed energy variation can be explained as being simply due to a variation of the projected velocity and beaming factor of the line-forming region towards us.",
"date": "2018-12",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "620",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A153",
"id_number": "CaltechAUTHORS:20190102-155139776",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190102-155139776",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)",
"grant_number": "PRIN-INAF 2014"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1051/0004-6361/201732132",
"primary_object": {
"basename": "1809.05691.pdf",
"url": "https://authors.library.caltech.edu/records/ehwb0-9t616/files/1809.05691.pdf"
},
"related_objects": [
{
"basename": "aa32132-17.pdf",
"url": "https://authors.library.caltech.edu/records/ehwb0-9t616/files/aa32132-17.pdf"
}
],
"pub_year": "2018",
"author_list": "F\u00fcrst, F.; Falkner, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7xc68-5r269",
"eprint_id": 90668,
"eprint_status": "archive",
"datestamp": "2023-08-19 12:40:53",
"lastmod": "2026-03-31 19:57:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Balokovi\u0107-Mislav",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Alexander-David-M",
"name": {
"family": "Alexander",
"given": "D. M."
},
"orcid": "0000-0002-5896-6313"
},
{
"id": "Annuar-Adlyka",
"name": {
"family": "Annuar",
"given": "A."
},
"orcid": "0000-0003-0387-1429"
},
{
"id": "Earnshaw-Hannah-P",
"name": {
"family": "Earnshaw",
"given": "H. P."
},
"orcid": "0000-0001-5857-5622"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Hornschemeier-Ann-E",
"name": {
"family": "Hornschemeier",
"given": "A. E."
},
"orcid": "0000-0001-8667-2681"
},
{
"id": "Lehmer-Bret-D",
"name": {
"family": "Lehmer",
"given": "B."
},
"orcid": "0000-0003-2192-3296"
},
{
"id": "Powell-Meredith-C",
"name": {
"family": "Powell",
"given": "M. C."
},
"orcid": "0000-0003-2284-8603"
},
{
"id": "Ptak-Andrew",
"name": {
"family": "Ptak",
"given": "A."
},
"orcid": "0000-0001-5655-1440"
},
{
"id": "Rangelov-Blagoy",
"name": {
"family": "Rangelov",
"given": "B."
},
"orcid": "0000-0002-9282-5207"
},
{
"id": "Roberts-Timothy-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Zezas-Andreas",
"name": {
"family": "Zezas",
"given": "A."
},
"orcid": "0000-0001-8952-676X"
}
]
},
"title": "A Long Hard-X-Ray Look at the Dual Active Galactic Nuclei of M51 with NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: individual (M51) \u2013 galaxies: nuclei \u2013 X-rays: binaries \u2013 X-rays: galaxies",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2018 May 29; revised 2018 September 6; accepted 2018 September 12; published 2018 November 5. \n\nThe authors thank the anonymous referee for the thorough and detailed review of our manuscript, which improved it. M. Balokovi\u0107 acknowledges support from the Black Hole Initiative at Harvard University, through the grant from the John Templeton Foundation. M.K. acknowledges support from NASA through ADAP award NNH16CT03C. D.M.A. acknowledges the Science and Technology Facilities Council (STFC) through grant ST/P000541/1. The work of D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. A.Z. acknowledges funding from the European Research Council under the European Unions Seventh Framework Programme (FP/2007\u20132013)/ERC Grant Agreement n. 617001. Support for this work was provided by the National Aeronautics and Space Administration through Chandra Award Number GO7-18105X issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. This work was also supported under NASA contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacilities: Chandra (ACIS) - , NuSTAR - , Hale (DBSP) - .\n\nPublished - Brightman_2018_ApJ_867_110.pdf
Accepted Version - 1805.12140.pdf
",
"abstract": "We present a broadband X-ray spectral analysis of the M51 system, including the dual active galactic nuclei (AGNs) and several off-nuclear point sources. Using a deep observation by NuSTAR, new high-resolution coverage of M51b by Chandra, and the latest X-ray torus models, we measure the intrinsic X-ray luminosities of the AGNs in these galaxies. The AGN of M51a is found to be Compton-thick, and both AGNs have very low accretion rates (\u03bb_Edd) < 10^(-4)). The latter is surprising considering that the galaxies of M51 are in the process of merging, which is generally predicted to enhance nuclear activity. We find that the covering factor of the obscuring material in M51a is 0.26 \u00b1 0.03, consistent with the local AGN obscured fraction at L_X ~10^(40) erg s^(\u22121). The substantial obscuring column does not support theories that the torus, presumed responsible for the obscuration, disappears at these low accretion luminosities. However, the obscuration may have resulted from the gas infall driven by the merger rather than the accretion process. We report on several extranuclear sources with L_X > 10^(-39) erg s^(\u22121) and find that a spectral turnover is present below 10 keV in most such sources, in line with recent results on ultraluminous X-ray sources.",
"date": "2018-11-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "867",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 110",
"id_number": "CaltechAUTHORS:20181106-105511630",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181106-105511630",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Harvard University"
},
{
"agency": "John Templeton Foundation"
},
{
"agency": "NASA",
"grant_number": "NNH16CT03C"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/P000541/1"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "617001"
},
{
"agency": "NASA",
"grant_number": "GO7-18105X"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aae1ae",
"primary_object": {
"basename": "1805.12140.pdf",
"url": "https://authors.library.caltech.edu/records/7xc68-5r269/files/1805.12140.pdf"
},
"related_objects": [
{
"basename": "Brightman_2018_ApJ_867_110.pdf",
"url": "https://authors.library.caltech.edu/records/7xc68-5r269/files/Brightman_2018_ApJ_867_110.pdf"
}
],
"pub_year": "2018",
"author_list": "Brightman, M.; Balokovi\u0107, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/h06d2-kny41",
"eprint_id": 90865,
"eprint_status": "archive",
"datestamp": "2023-08-22 00:18:19",
"lastmod": "2026-03-31 22:33:25",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Masini-A",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Comastri-A",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Civano-Francesca",
"name": {
"family": "Civano",
"given": "F."
},
"orcid": "0000-0002-2115-1137"
},
{
"id": "Hickox-R-C",
"name": {
"family": "Hickox",
"given": "R. C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Carroll-C-M",
"name": {
"family": "Carroll",
"given": "C. M."
},
"orcid": "0000-0003-3574-2963"
},
{
"id": "Suh-Hyewon",
"name": {
"family": "Suh",
"given": "H."
},
"orcid": "0000-0002-2536-1633"
},
{
"id": "Brandt-W-N",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "DiPompeo-M-A",
"name": {
"family": "DiPompeo",
"given": "M. A."
},
"orcid": "0000-0001-6788-1701"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
}
]
},
"title": "The NuSTAR Extragalactic Surveys: Unveiling Rare, Buried AGNs and Detecting the Contributors to the Peak of the Cosmic X-Ray Background",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active; galaxies: Seyfert",
"note": "\u00a9 2018. The American Astronomical Society. \n\nReceived 2018 July 20; revised 2018 August 31; accepted 2018 September 27; published 2018 November 12. \n\nWe thank the anonymous referee, whose comments helped improve the quality and clarity of the paper. This work was supported under NASA Contract NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has also made use of data obtained from the Chandra Data Archive and the Chandra Source Catalog, and software provided by the Chandra X-ray Center (CXC). Figure 4 is partially based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under ESO programme ID 179.A-2005 and on data products produced by TERAPIX and the Cambridge Astronomy Survey Unit on behalf of the UltraVISTA consortium. The DEIMOS spectrum presented herein was obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. This research made use of Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013; The Astropy Collaboration et al. 2018), and XSPEC (Arnaud 1996). \n\nA.M. and A.C. acknowledge support from the ASI/INAF grant I/037/12/0011/13. R.C.H. acknowledges support from the National Science Foundation through CAREER award 1554584, and from NASA through grant number NNX15AP24G. W.N.B. acknowledges support from Caltech NuSTAR subcontract 44A-1092750. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Chandra - . \n\nSoftware: NuSTARDAS, FTOOLS.\n\nPublished - Masini_2018_ApJ_867_162.pdf
Accepted Version - 1810.00010
",
"abstract": "We report on the results of active galactic nuclei (AGNs) detection by NuSTAR performed in three extragalactic survey fields (COSMic Evolutionary Survey field (COSMOS), Ultra Deep Survey (UDS), and Extended Chandra Deep Field-South (ECDFS)) in three hard bands, namely H1 (8\u201316 keV), H2 (16\u201324 keV), and VH (35\u201355 keV). The aggregated area of the surveys is ~2.7 deg^2. While a large number of sources is detected in the H1 band (72 at the 97% level of reliability), the H2 band directly probing close to the peak of the Cosmic X-ray Background (CXB) returns four significant detections, and two tentative (although not significant) detections are found in the VH-band. All of the sources detected above 16 keV are also detected at lower energies. We compute the integral number counts for sources in such bands, which show broad consistency with population-synthesis models of the CXB. We furthermore identify two Compton-thick AGNs, one in the COSMOS field, associated with a hard and faint Chandra source, and one in the UDS field, never detected in the X-ray band before. Both sources are at the same redshift z ~ 1.25, which shifts their Compton-hump into the H1 band, and were previously missed in the usually employed NuSTAR bands, confirming the potential for using the H1 band to discover obscured AGNs at z > 1 in deep surveys.",
"date": "2018-11-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "867",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 162",
"id_number": "CaltechAUTHORS:20181113-112609358",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181113-112609358",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "W. M. Keck Foundation"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0011/13"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
},
{
"agency": "NSF",
"grant_number": "AST-1554584"
},
{
"agency": "NASA",
"grant_number": "NNX15AP24G"
},
{
"agency": "Caltech NuSTAR subcontract",
"grant_number": "44A-1092750"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aae539",
"primary_object": {
"basename": "1810.00010",
"url": "https://authors.library.caltech.edu/records/h06d2-kny41/files/1810.00010"
},
"related_objects": [
{
"basename": "Masini_2018_ApJ_867_162.pdf",
"url": "https://authors.library.caltech.edu/records/h06d2-kny41/files/Masini_2018_ApJ_867_162.pdf"
}
],
"pub_year": "2018",
"author_list": "Masini, A.; Comastri, A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/sz2gq-etx80",
"eprint_id": 91318,
"eprint_status": "archive",
"datestamp": "2023-08-19 12:27:19",
"lastmod": "2026-04-01 00:06:02",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Buisson-D-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
}
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Vasudevan-R-V",
"name": {
"family": "Vasudevan",
"given": "R. V."
}
},
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "A. M."
}
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "S. E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "F. E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "W. W."
}
},
{
"id": "Farrah-D",
"name": {
"family": "Farrah",
"given": "D."
},
"orcid": "0000-0003-1748-2010"
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "C. J."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "W. W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "NuSTAR observations of Mrk 766: distinguishing reflection from absorption",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs, black hole physics, galaxies: individual: Mrk 766, galaxies: Seyfert",
"note": "\u00a9 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) \n\nAccepted 2018 July 30. Received 2018 July 27; in original form 2017 May 23. \n\nDJKB, MLP, and RVV acknowledge financial support from the Science and Technology Facilities Council (STFC). ACF, AML, CP, and MLP acknowledge support from the ERC Advanced Grant FEEDBACK 340442. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This work has made use of observations obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. We acknowledge support from the Faculty of the European Space Astronomy Centre (ESAC).\n\nPublished - sty2081.pdf
Accepted Version - 1808.00014
",
"abstract": "We present two new NuSTAR observations of the narrow-line Seyfert 1 (NLS1) galaxy Mrk 766 and give constraints on the two scenarios previously proposed to explain its spectrum and that of other NLS1s: relativistic reflection and partial covering. The NuSTAR spectra show a strong hard (>15 \u2009keV) X-ray excess, while simultaneous soft X-ray coverage of one of the observations provided by XMM\u2013Newton constrains the ionized absorption in the source. The pure reflection model requires a black hole of high spin (a > 0.92) viewed at a moderate inclination (\u2060i=46^(+1)_(\u22124)\u2218\u2060). The pure partial covering model requires extreme parameters: the cut-off of the primary continuum is very low (\u206022^(+7)_(\u22125)\u2009keV) in one observation and the intrinsic X-ray emission must provide a large fraction (75 per cent) of the bolometric luminosity. Allowing a hybrid model with both partial covering and reflection provides more reasonable absorption parameters and relaxes the constraints on reflection parameters. The fractional variability reduces around the iron K band and at high energies including the Compton hump, suggesting that the reflected emission is less variable than the continuum.",
"date": "2018-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "480",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3689-3701",
"id_number": "CaltechAUTHORS:20181128-153100321",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181128-153100321",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Space Astronomy Centre"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/sty2081",
"primary_object": {
"basename": "1808.00014",
"url": "https://authors.library.caltech.edu/records/sz2gq-etx80/files/1808.00014"
},
"related_objects": [
{
"basename": "sty2081.pdf",
"url": "https://authors.library.caltech.edu/records/sz2gq-etx80/files/sty2081.pdf"
}
],
"pub_year": "2018",
"author_list": "Buisson, D. J. K.; Parker, M. L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5x61c-yn009",
"eprint_id": 90417,
"eprint_status": "archive",
"datestamp": "2023-09-15 06:09:01",
"lastmod": "2026-03-31 20:52:12",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Richardson-J-D",
"name": {
"family": "Richardson",
"given": "John D."
},
"orcid": "0000-0003-4041-7540"
},
{
"id": "Belcher-J-W",
"name": {
"family": "Belcher",
"given": "John W."
}
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "Alan C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Decker-R",
"name": {
"family": "Decker",
"given": "Robert"
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Edward C."
},
"orcid": "0000-0002-2010-5462"
}
]
},
"title": "Voyager 2 Observations of Plasma and Pressure Pulses",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2018 Published under licence by IOP Publishing Ltd. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nAccepted papers received: 7 September 2018; Published online: 24 October 2018. \n\nWe thank SPDF for the Voyager 2 magnetometer data and CRS (P.I., E. C. Stone) and LECP (P.I., S. M. Krimigis) for providing data through their web sites. JDR was supported under NASA contract 959203 from the Jet Propulsion Laboratory to the Massachusetts Institute of Technology. RBD was supported by NASA contract NNN06AA01C. ECS and ACE were supported by NASA grant NNN12AA01C.\n\nPublished - Richardson_2018_J._Phys._3A_Conf._Ser._1100_012019.pdf
",
"abstract": "This paper provides the latest data from Voyager 2 on plasma characteristics in the heliosheath including the observations of pressure waves in the plasma and particle data. Models and observations show that solar transients drive pressure waves through the heliosphere. Pressure pulses that could drive heliosheath waves are observed near the previous solar maximum upstream of the termination shock. We show that the most recent data is consistent with the presence of pressure waves and compare the heliosheath waves with the pressure increases in the heliosheath. The magnetic field is better correlated with density and galactic cosmic ray intensities in the supersonic solar wind than in the heliosheath. The galactic cosmic rays are correlated with the plasma and particles with a ~30-day lag in both the supersonic wind and heliosheath.",
"date": "2018-10-24",
"date_type": "published",
"publication": "Journal of Physics: Conference Series",
"volume": "1100",
"publisher": "IOP",
"pagerange": "Art. No. 012019",
"id_number": "CaltechAUTHORS:20181025-112020309",
"issn": "1742-6596",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181025-112020309",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "959203"
},
{
"agency": "NASA",
"grant_number": "NNN06AA01C"
},
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1088/1742-6596/1100/1/012019",
"primary_object": {
"basename": "Richardson_2018_J._Phys._3A_Conf._Ser._1100_012019.pdf",
"url": "https://authors.library.caltech.edu/records/5x61c-yn009/files/Richardson_2018_J._Phys._3A_Conf._Ser._1100_012019.pdf"
},
"pub_year": "2018",
"author_list": "Richardson, John D.; Belcher, John W.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jr44y-7pg86",
"eprint_id": 90350,
"eprint_status": "archive",
"datestamp": "2023-08-19 12:02:44",
"lastmod": "2026-03-31 21:07:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kamraj-N",
"name": {
"family": "Kamraj",
"given": "N."
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "A."
}
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
}
]
},
"title": "Coronal Properties of Swift/BAT-selected Seyfert 1 AGNs Observed with NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: active \u2013 X-rays: galaxies",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2018 April 20; revised 2018 August 23; accepted 2018 August 24; published 2018 October 19. \n\nWe would like to thank the referee for comments that helped improve the final version of the manuscript. We have made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). M.B. acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program (grant NNX14AQ07H) and support from the black hole Initiative at Harvard University, through the grant from the John Templeton Foundation. \n\nFacility: NuSTAR. -\n\nPublished - Kamraj_2018_ApJ_866_124.pdf
Accepted Version - 1809.01757.pdf
",
"abstract": "The NuSTAR observatory, with its high sensitivity in hard X-rays, has enabled detailed broadband modeling of the X-ray spectra of active galactic nuclei (AGNs), thereby allowing constraints to be placed on the high-energy cutoff of the X-ray coronal continuum. We investigate the spectral properties of a sample of 46 NuSTAR-observed Seyfert 1 AGNs selected from the Swift/Burst Alert Telescope 70 month hard X-ray survey. Our measurements of the high-energy cutoff of the continuum from modeling the NuSTAR X-ray spectra are used to map out the temperature\u2013compactness (\u03b8\u2013l) plane for AGN coronae. We find that most of the coronae lie clustered near the boundary for runaway pair production, suggesting that annihilation and pair production act to regulate the temperature of the corona. We discuss the implications of coronae whose high-energy cutoff may indicate a low coronal temperature on the heating and thermalization mechanisms in the corona.",
"date": "2018-10-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "866",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 124",
"id_number": "CaltechAUTHORS:20181023-091921294",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181023-091921294",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
},
{
"agency": "Harvard University"
},
{
"agency": "John Templeton Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aadd0d",
"primary_object": {
"basename": "1809.01757.pdf",
"url": "https://authors.library.caltech.edu/records/jr44y-7pg86/files/1809.01757.pdf"
},
"related_objects": [
{
"basename": "Kamraj_2018_ApJ_866_124.pdf",
"url": "https://authors.library.caltech.edu/records/jr44y-7pg86/files/Kamraj_2018_ApJ_866_124.pdf"
}
],
"pub_year": "2018",
"author_list": "Kamraj, N.; Harrison, F. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/q9pr8-k2f81",
"eprint_id": 90401,
"eprint_status": "archive",
"datestamp": "2023-08-19 12:03:16",
"lastmod": "2026-04-01 03:07:35",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pearlman-A-B",
"name": {
"family": "Pearlman",
"given": "Aaron B."
},
"orcid": "0000-0002-8912-0732"
},
{
"id": "Majid-W",
"name": {
"family": "Majid",
"given": "Walid A."
},
"orcid": "0000-0002-4694-4221"
},
{
"id": "Prince-T-A",
"name": {
"family": "Prince",
"given": "Thomas A."
},
"orcid": "0000-0002-8850-3627"
},
{
"id": "Kocz-J",
"name": {
"family": "Kocz",
"given": "Jonathon"
},
"orcid": "0000-0003-0249-7586"
},
{
"id": "Horiuchi-Shinji",
"name": {
"family": "Horiuchi",
"given": "Shinji"
}
}
]
},
"title": "Pulse Morphology of the Galactic Center Magnetar PSR J1745\u20132900",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Galaxy: center \u2013 pulsars: individual (PSR J1745\u20132900) \u2013 scattering \u2013 stars: magnetars \u2013 stars: neutron",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2018 April 30; revised 2018 August 23; accepted 2018 August 30; published 2018 October 24. \n\nWe thank the referee for valuable comments that helped us improve this paper. We also thank Professor Roger Blandford for insightful discussions and suggestions. \n\nA. B. Pearlman acknowledges support by the Department of Defense (DoD) through the National Defense Science and Engineering Graduate Fellowship (NDSEG) Program and by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469. \n\nWe thank the Jet Propulsion Laboratory and Caltech's President's and Director's Fund for partial support at JPL and the Caltech campus. We also thank Joseph Lazio and Charles Lawrence for providing programmatic support for this work. A portion of this research was performed at the Jet Propulsion Laboratory, California Institute of Technology and the Caltech campus, under a Research and Technology Development Grant through a contract with the National Aeronautics and Space Administration. U.S. government sponsorship is acknowledged.\n\nPublished - Pearlman_2018_ApJ_866_160.pdf
Accepted Version - 1809.02140.pdf
",
"abstract": "We present results from observations of the Galactic Center magnetar, PSR J1745\u20132900, at 2.3 and 8.4 GHz with the NASA Deep Space Network 70 m antenna, DSS-43. We study the magnetar's radio profile shape, flux density, radio spectrum, and single pulse behavior over a ~1 year period between MJDs 57233 and 57621. In particular, the magnetar exhibits a significantly negative average spectral index of \u27e8\u03b1\u27e9 = -1.86 \u00b1 0.02 when the 8.4 GHz profile is single-peaked, which flattens considerably when the profile is double-peaked. We have carried out an analysis of single pulses at 8.4 GHz on MJD 57479 and find that giant pulses and pulses with multiple emission components are emitted during a significant number of rotations. The resulting single pulse flux density distribution is incompatible with a log-normal distribution. The typical pulse width of the components is ~1.8 ms, and the prevailing delay time between successive components is ~7.7 ms. Many of the single pulse emission components show significant frequency structure over bandwidths of ~100 MHz, which we believe is the first observation of such behavior from a radio magnetar. We report a characteristic single pulse broadening timescale of \u27e8\u03c4_d\u27e9 = 6.9 \u00b1 0.2 at 8.4 GHz. We find that the pulse broadening is highly variable between emission components and cannot be explained by a thin scattering screen at distances \u22731 kpc. We discuss possible intrinsic and extrinsic mechanisms for the magnetar's emission and compare our results to other magnetars, high magnetic field pulsars, and fast radio bursts.",
"date": "2018-10-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "866",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 160",
"id_number": "CaltechAUTHORS:20181024-142448369",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181024-142448369",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship"
},
{
"agency": "NSF Graduate Research Fellowship",
"grant_number": "DGE-1144469"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "JPL President and Director's Fund"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aade4d",
"primary_object": {
"basename": "1809.02140.pdf",
"url": "https://authors.library.caltech.edu/records/q9pr8-k2f81/files/1809.02140.pdf"
},
"related_objects": [
{
"basename": "Pearlman_2018_ApJ_866_160.pdf",
"url": "https://authors.library.caltech.edu/records/q9pr8-k2f81/files/Pearlman_2018_ApJ_866_160.pdf"
}
],
"pub_year": "2018",
"author_list": "Pearlman, Aaron B.; Majid, Walid A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/g4bc7-dqp55",
"eprint_id": 90071,
"eprint_status": "archive",
"datestamp": "2023-08-22 00:09:37",
"lastmod": "2026-03-31 22:52:46",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yerong",
"name": {
"family": "Xu",
"given": "Yerong"
}
},
{
"id": "Nampalliwar-S",
"name": {
"family": "Nampalliwar",
"given": "Sourabh"
}
},
{
"id": "Abdikamalov-A-B",
"name": {
"family": "Abdikamalov",
"given": "Askar B."
}
},
{
"id": "Ayzenberg-D",
"name": {
"family": "Ayzenberg",
"given": "Dimitry"
}
},
{
"id": "Bambi-C",
"name": {
"family": "Bambi",
"given": "Cosimo"
},
"orcid": "0000-0002-3180-9502"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Jiang-Jiachen",
"name": {
"family": "Jiang",
"given": "Jiachen"
},
"orcid": "0000-0002-9639-4352"
}
]
},
"title": "A Study of the Strong Gravity Region of the Black Hole in GS 1354\u2013645",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks; black hole physics; gravitation",
"note": "\u00a9 2018. The American Astronomical Society. \n\nReceived 2018 July 27; revised 2018 August 14; accepted 2018 August 18; published 2018 October 1. \n\nThis work was supported by the National Natural Science Foundation of China (NSFC), grant No. U1531117, and Fudan University, grant No. IDH1512060. S.N. acknowledges support from the Excellence Initiative at Eberhard-Karls Universit\u00e4t T\u00fcbingen. A.B.A. also acknowledges the support from the Shanghai Government Scholarship (SGS). C.B. and J.A.G. also acknowledge support from the Alexander von Humboldt Foundation. J.J. is supported by the Cambridge Trust and the Chinese Scholarship Council Joint Scholarship Program (201604100032).\n\nPublished - Xu_2018_ApJ_865_134.pdf
Submitted - 1807.10243
",
"abstract": "It is thought that the spacetime metric around astrophysical black holes is well described by the Kerr solution of Einstein's gravity. However, robust observational evidence of the Kerr nature of these objects is still lacking. Here we fit the X-ray spectrum of the stellar-mass black hole in GS 1354\u2013645 with a disk reflection model beyond Einstein's gravity in order test the Kerr black hole hypothesis. We consider the Johannsen metric with the deformation parameters \u03b1_(13) and \u03b1_(22). The Kerr metric is recovered for \u03b1_(13) = \u03b1_(22) = 0. For \u03b1_(22) = 0, our measurements of the black hole spin and of the deformation parameter \u03b1 13 are a_* > 0.975 and \u22120.34 < \u03b1_(13) < 0.16, respectively. For \u03b1 13 = 0, we find a_* > 0.975 and \u22120.09 < \u03b1_(22) < 0.42. All the reported uncertainties are at 99% of confidence level for two relevant parameters.",
"date": "2018-10-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "865",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 134",
"id_number": "CaltechAUTHORS:20181001-131357805",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181001-131357805",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "National Natural Science Foundation of China",
"grant_number": "U1531117"
},
{
"agency": "Fudan University",
"grant_number": "IDH1512060"
},
{
"agency": "Eberhard-Karls Universit\u00e4t T\u00fcbingen"
},
{
"agency": "Shanghai Government Scholarship"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "Cambridge Overseas Trust"
},
{
"agency": "Chinese Scholarship Council",
"grant_number": "201604100032"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aadb9d",
"primary_object": {
"basename": "1807.10243",
"url": "https://authors.library.caltech.edu/records/g4bc7-dqp55/files/1807.10243"
},
"related_objects": [
{
"basename": "Xu_2018_ApJ_865_134.pdf",
"url": "https://authors.library.caltech.edu/records/g4bc7-dqp55/files/Xu_2018_ApJ_865_134.pdf"
}
],
"pub_year": "2018",
"author_list": "Xu, Yerong; Nampalliwar, Sourabh; et al."
},
{
"id": "https://authors.library.caltech.edu/records/aswm5-sf592",
"eprint_id": 90251,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:43:27",
"lastmod": "2026-04-01 02:16:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
}
]
},
"title": "The Ground Level Enhancement Event of September 2017 and Other Large Solar Energetic Particle Events of Cycle 24",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2018 American Geophysical Union. \n\nReceived 6 JUL 2018; Accepted 2 OCT 2018; Accepted article online 10 OCT 2018; Published online 29 OCT 2018. \n\nWe are very grateful to Ingmar Sandberg for providing updated estimates of the effective energies for GOES\u20108, GOES\u201011, and GOES\u201013, and for discussions on their use. This work was supported by NSF grants 1156004 and 1156138 and NASA grants NNX11075G, 80NSSC18K0223, and NNX15AG09G. The GOES 8\u201015 particle data are produced in real time by the NOAA Space Weather Prediction Center (SWPC) and are distributed by the NOAA National Geophysical Data Center (NGDC). The ACE data are available through the ACE Science Center (www.srl.caltech.edu/ACE/ASC), and the STEREO data are available through the STEREO SEP Suite data pages (www.srl.caltech.edu/STEREO). The SOHO/EPHIN data are available at www2.physik.uni\u2010kiel.de/SOHO/phpeph/EPHIN.htm and the SAMPEX/PET data can be accessed at www.srl.caltech.edu/sampex/DataCenter/index.html and www.srl.caltech.edu/sampex/DataCenter/DATA/EventSpectra/index_ace.html.\n\nPublished - Cohen_et_al-2018-Space_Weather.pdf
",
"abstract": "The 10 September 2017 solar energetic particle (SEP) event was the largest since June 2015 and one of only two ground\u2010level enhancement (GLE) events of solar cycle 24. GLE events are subset of large SEP events (~15% of events identified by Space Weather Prediction Center) with particularly hard spectra, making them a substantial space weather hazard to space\u2010based instrumentation and exposed astronauts. We present analysis of the 10 September 2017 event and compare it to the other cycle 24 GLE events, to those of cycle 23, and also to two extreme SEP events observed by Solar Terrestrial Relations Observatory (STEREO). We find the 10 September 2017 event had a broken power law spectrum typical of GLE events but was softer than average at high energies. However, it was hard at low energies with a relatively high break energy, which led to 100\u2010MeV proton fluences within a factor of 4.5 of the largest cycle 23 GLE events. The composition was nominal, except for a low Fe/O ratio, which has also been seen in large SEP events this cycle, but is somewhat atypical of the cycle 23 GLE events. The extreme events seen by STEREO exhibited very hard high\u2010energy spectra, with one event producing ~80\u2010MeV proton fluences larger than the largest cycle 23 GLE event. However, even including STEREO events, the top 10 largest cycle 24 events are, on average, 2.4 times smaller than the top 10 of cycle 23 based on >10\u2010MeV proton fluences.",
"date": "2018-10",
"date_type": "published",
"publication": "Space Weather",
"volume": "16",
"number": "10",
"publisher": "American Geophysical Union",
"pagerange": "1616-1623",
"id_number": "CaltechAUTHORS:20181011-131543573",
"issn": "1542-7390",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181011-131543573",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "AGS-1156004"
},
{
"agency": "NSF",
"grant_number": "AGS-1156138"
},
{
"agency": "NASA",
"grant_number": "NNX11075G"
},
{
"agency": "NASA",
"grant_number": "80NSSC18K0223"
},
{
"agency": "NASA",
"grant_number": "NNX15AG09G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1029/2018SW002006",
"primary_object": {
"basename": "Cohen_et_al-2018-Space_Weather.pdf",
"url": "https://authors.library.caltech.edu/records/aswm5-sf592/files/Cohen_et_al-2018-Space_Weather.pdf"
},
"pub_year": "2018",
"author_list": "Cohen, C. M. S. and Mewaldt, R. A."
},
{
"id": "https://authors.library.caltech.edu/records/qm82v-7xj61",
"eprint_id": 85195,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:32:31",
"lastmod": "2023-10-18 17:57:14",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kosec-P",
"name": {
"family": "Kosec",
"given": "P."
}
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
}
]
},
"title": "Evidence for a Variable Ultrafast Outflow in the Newly Discovered Ultraluminous Pulsar NGC 300 ULX-1",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices). \n\nAccepted 2018 June 12. Received 2018 June 12; in original form 2018 March 5. Published: 20 June 2018. \n\nWe are grateful to the anonymous referee for useful comments that improved the clarity and quality of the paper. PK acknowledges support from the Science and Technology Facilities Council (STFC). CP and ACF acknowledge support from the European Research Council Advanced Grant Feedback 340442. DJW acknowledges support from STFC Ernest Rutherford fellowships. This work is based on observations obtained with XMM\u2013Newton, an ESA science mission funded by ESA Member States and USA (NASA). This research has used the NASA/IPAC Extragalactic Database (NED) that is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has used the SIMBAD database, operated at CDS, Strasbourg, France.\n\nPublished - sty1626.pdf
Submitted - 1803.02367v1.pdf
",
"abstract": "Ultraluminous pulsars are a definite proof that persistent super-Eddington accretion occurs in nature. They support the scenario according to which most Ultraluminous X-ray Sources (ULXs) are super-Eddington accretors of stellar mass rather than sub-Eddington intermediate mass black holes. An important prediction of theories of supercritical accretion is the existence of powerful outflows of moderately ionized gas at mildly relativistic speeds. In practice, the spectral resolution of X-ray gratings such as RGS onboard XMM\u2013Newton is required to resolve their observational signatures in ULXs. Using RGS, outflows have been discovered in the spectra of three ULXs (none of which are currently known to be pulsars). Most recently, the fourth ultraluminous pulsar was discovered in NGC 300. Here we report detection of an ultrafast outflow (UFO) in the X-ray spectrum of the object, with a significance of more than 3\u03c3, during one of the two simultaneous observations of the source by XMM\u2013Newton and NuSTAR in December 2016. The outflow has a projected velocity of\u200965 000\u2009km\u2009s^(\u22121)(0.22c) and a high ionization factor with a log value of 3.9. This is the first direct evidence for a UFO in a neutron star ULX and also the first time that this evidence in a ULX spectrum is seen in both soft and hard X-ray data simultaneously. We find no evidence of the UFO during the other observation of the object, which could be explained by either clumpy nature of the absorber or a slight change in our viewing angle of the accretion flow.",
"date": "2018-09-21",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "479",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3978-3986",
"id_number": "CaltechAUTHORS:20180308-083847600",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180308-083847600",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technologies Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Space Agency (ESA)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/sty1626",
"primary_object": {
"basename": "1803.02367v1.pdf",
"url": "https://authors.library.caltech.edu/records/qm82v-7xj61/files/1803.02367v1.pdf"
},
"related_objects": [
{
"basename": "sty1626.pdf",
"url": "https://authors.library.caltech.edu/records/qm82v-7xj61/files/sty1626.pdf"
}
],
"pub_year": "2018",
"author_list": "Kosec, P.; Pinto, C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ahn06-d5974",
"eprint_id": 89824,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:32:00",
"lastmod": "2026-03-31 22:15:29",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Israel-M-H",
"name": {
"family": "Israel",
"given": "M. H."
},
"orcid": "0000-0002-8104-208X"
},
{
"id": "Lave-K-A",
"name": {
"family": "Lave",
"given": "K. A."
}
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Binns-W-R",
"name": {
"family": "Binns",
"given": "W. R."
},
"orcid": "0000-0001-6110-3407"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"id": "de-Nolfo-G-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "von-Rosenvinge-T-T",
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
}
]
},
"title": "Elemental Composition at the Cosmic-Ray Source Derived from the ACE-CRIS Instrument. I. _6C to _(28)Ni",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "astroparticle physics \u2013 cosmic rays \u2013 ISM: abundances",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2018 January 29; revised 2018 July 16; accepted 2018 August 3; published 2018 September 21. \n\nNASA grants NNX08AI11G and NNX13AH66G supported the work performed at the California Institute of Technology, the Jet Propulsion Laboratory, and Washington University in St. Louis. The work done at Goddard Space Flight Center was funded by NASA through the ACE Project. We thank Nasser Barghouty for his private communication of updated partial interaction cross sections of protons on heavy nuclei, and we thank Christina Cohen for her editorial assistance in preparing this manuscript.\n\nPublished - Israel_2018_ApJ_865_69.pdf
",
"abstract": "We report new elemental source abundances from _6C to _(28)Ni for galactic cosmic rays, using observations from the Cosmic Ray Isotope Spectrometer (CRIS) on board the NASA Advanced Composition Explorer spacecraft. Abundances were calculated using CRIS energy spectra at energies below 550 MeV/nucleon from the 1997\u201398 and 2009\u201310 solar-minimum periods, as well as from the 2001\u201303 solar-maximum period. These new results, when combined with results for heavier elements reported in a forthcoming paper, are consistent with a model of galactic cosmic-ray origin where nuclei found in interstellar grains are accelerated preferentially over those found in interstellar gas, with this acceleration happening in OB associations.",
"date": "2018-09-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "865",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 69",
"id_number": "CaltechAUTHORS:20180921-095050945",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-095050945",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX08AI11G"
},
{
"agency": "NASA",
"grant_number": "NNX13AH66G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.3847/1538-4357/aad867",
"primary_object": {
"basename": "Israel_2018_ApJ_865_69.pdf",
"url": "https://authors.library.caltech.edu/records/ahn06-d5974/files/Israel_2018_ApJ_865_69.pdf"
},
"pub_year": "2018",
"author_list": "Israel, M. H.; Lave, K. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/r9vxs-49d20",
"eprint_id": 89696,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:31:54",
"lastmod": "2026-03-31 21:47:01",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kennea-J-A",
"name": {
"family": "Kennea",
"given": "Jamie A."
},
"orcid": "0000-0002-6745-4790"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "Jon M."
}
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "Poshak"
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
}
]
},
"title": "The Hard State of the Highly Absorbed High Inclination Black Hole Binary Candidate Swift J1658.2\u20134242 Observed by NuSTAR and Swift",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 X-rays: binaries \u2013 X-rays: individual (Swift J1658.2-4242)",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2018 May 18; revised 2018 July 30; accepted 2018 August 9; published 2018 September 18. \n\nWe thank the referee for helpful comments that improved this work. D.J.W. acknowledges support from STFC Ernest Rutherford Fellowship. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Xu_2018_ApJ_865_18.pdf
Accepted Version - 1805.07705.pdf
",
"abstract": "We present a spectral and timing analysis of the newly reported Galactic X-ray transient Swift J1658.2\u20134242 observed by Nuclear Spectroscopic Telescope Array (NuSTAR) and Swift. The broadband X-ray continuum is typical of a black hole binary in the bright hard state, with a photon index of \u0393 = 1.63 \u00b1 0.02 and a low coronal temperature of kT_e = 22 \u00b1 1 keV, corresponding to a low spectral cutoff well constrained by NuSTAR. Spectral modeling of the relativistic disk reflection features, consisting of a broad Fe K\u03b1 line and the Compton reflection hump, reveals that the black hole is rapidly spinning with the spin parameter of a* > 0.96, and the inner accretion disk is viewed at a high inclination angle of I = 64^(2 o)_(-3) (statistical errors, 90% confidence). The high inclination is independently confirmed by dips in the light curves, which can be explained by absorbing material located near the disk plane temporarily obscuring the central region. In addition, we detect an absorption line in the NuSTAR spectra centered at 7.03^(+0.04)_(-0.03) keV. If associated with ionized Fe K absorption lines, this provides evidence for the presence of outflowing material in the low/hard state of a black hole binary candidate. A timing analysis shows the presence of a type-C quasi-periodic oscillation in the power spectrum, with the frequency increasing from ~0.14 to ~0.21 Hz during the single NuSTAR exposure. Our analysis reveals that Swift J1658.2\u20134242 displays characteristics typical for a black hole binary that is viewed at a high inclination angle, making it a good system for studying the accretion geometry in black hole binaries.",
"date": "2018-09-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "865",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 18",
"id_number": "CaltechAUTHORS:20180918-091012752",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180918-091012752",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aada03",
"primary_object": {
"basename": "1805.07705.pdf",
"url": "https://authors.library.caltech.edu/records/r9vxs-49d20/files/1805.07705.pdf"
},
"related_objects": [
{
"basename": "Xu_2018_ApJ_865_18.pdf",
"url": "https://authors.library.caltech.edu/records/r9vxs-49d20/files/Xu_2018_ApJ_865_18.pdf"
}
],
"pub_year": "2018",
"author_list": "Xu, Yanjun; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nbzce-7pg44",
"eprint_id": 92093,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:27:29",
"lastmod": "2026-03-31 19:58:05",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Burnham-J-A",
"name": {
"family": "Burnham",
"given": "Jill A."
}
},
{
"id": "Cook-W-R",
"name": {
"family": "Cook",
"given": "Walter"
}
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Sanders-J-M",
"name": {
"family": "Sanders",
"given": "Julian M."
}
},
{
"id": "Sosanya-A-A",
"name": {
"family": "Sosanya",
"given": "Andrew A."
}
}
]
},
"title": "Characterization of Redlen CZT detectors for hard x-ray astronomy",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "CZT, Redlen Technologies, X-ray detectors, NuSTAR, astronomy",
"note": "\u00a9 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nThis work was supported under NASA grant NNX13AC55G.\n\nPublished - 1076214.pdf
",
"abstract": "We present the results of ongoing characterization of Cadmium Zinc Telluride (CZT) semiconductors produced by Redlen Technologies. In particular we hope to determine their viability for future X-ray astronomy missions such as the High Energy X-ray Probe (HEX-P). The fully fabricated hybrid detectors consist of CZT crystals with a collecting area of 2 cm \u00d7 2 cm and thickness of 3 mm mounted on a custom pixelated ASIC originally designed for the Nuclear Spectroscopic Telescope Array (NuSTAR) mission, which launched in 2012. We present the results of inter-pixel conductance and leakage current tests as well as spectral characterization using an 241Am source. Although further calibration and testing is necessary to determine the capabilities of these detectors, preliminary results indicate that Redlen CZT will be able to achieve spectral resolution and noise levels comparable to those of the CZT detectors currently in use aboard NuSTAR.",
"date": "2018-09-13",
"date_type": "published",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 1076214",
"id_number": "CaltechAUTHORS:20190104-094928664",
"isbn": "9781510620957",
"book_title": "Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XX",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190104-094928664",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX13AC55G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "Payne-S-A",
"name": {
"family": "Payne",
"given": "Stephen A."
}
},
{
"id": "James-R-B",
"name": {
"family": "James",
"given": "Ralph B."
}
},
{
"id": "Burger-A",
"name": {
"family": "Burger",
"given": "Arnold"
}
},
{
"id": "Fiederle-M",
"name": {
"family": "Fiederle",
"given": "Michael"
}
}
]
},
"doi": "10.1117/12.2321990",
"primary_object": {
"basename": "1076214.pdf",
"url": "https://authors.library.caltech.edu/records/nbzce-7pg44/files/1076214.pdf"
},
"pub_year": "2018",
"author_list": "Pike, Sean N.; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ajyj5-bw704",
"eprint_id": 89180,
"eprint_status": "archive",
"datestamp": "2023-09-29 01:32:46",
"lastmod": "2026-03-31 22:21:18",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "Thomas"
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Connors-R-M-T",
"name": {
"family": "Connors",
"given": "Riley M. T."
},
"orcid": "0000-0002-8908-759X"
},
{
"id": "McClintock-J-E",
"name": {
"family": "McClintock",
"given": "Jeffrey E."
}
},
{
"id": "Remillard-R-A",
"name": {
"family": "Remillard",
"given": "Ronald A."
},
"orcid": "0000-0003-4815-0481"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
}
]
},
"title": "Reflection Spectroscopy of the Black Hole Binary XTE J1752\u2212223 in Its Long-stable Hard State",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks; atomic processes; black hole physics; line: formation; X-rays: individual (XTE J1752\u2212223)",
"note": "\u00a9 2018. The American Astronomical Society. \n\nReceived 2018 May 11; revised 2018 July 2; accepted 2018 July 5; published 2018 August 27. \n\nThe authors dedicate the present work to the memory of our friend, colleague, and mentor Jeffrey E. McClintock, who passed on 2017 November 8. This paper grew from a program to explore black hole systems using RXTE under Jeff's leadership. We thank Jeff for his mentorship, his always open door, and for his friendship. Jeff's love for science inspired us, his relentless curiosity was a joy to share, and we miss him greatly. \n\nThis work was partially supported under NASA Contract No. NNG08FD60C. J.A.G. and R.M.T.C. acknowledge support from NASA Grant No. 80NSSC177K0515. J.A.G also acknowledges support from the Alexander von Humboldt Foundation. J.F.S has been supported by the NASA Einstein Fellowship, Grant No. PF5-160144. V.G. is supported through the Margarethe von Wrangell fellowship by the ESF and the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg.\n\nPublished - Garcia_2018_ApJ_864_25.pdf
Submitted - 1807_01949.pdf
",
"abstract": "We present a detailed spectral analysis of the black hole binary XTE J1752\u2212223 in the hard state of its 2009 outburst. Regular monitoring of this source by the Rossi X-ray Timing Explorer mission provided high signal-to-noise spectra along the outburst rise and decay. During one full month this source stalled at ~30% of its peak count rate at a constant hardness and intensity. By combining all the data in this exceptionally stable hard state, we obtained an aggregate proportional counter array spectrum (3\u201345 keV) with 100 million counts, and a corresponding high energy X-ray timing experiment spectrum (20\u2013140 keV) with 5.8 million counts. Implementing a version of our reflection code with a physical model for Comptonization, we obtain tight constraints on important physical parameters for this system. In particular, the inner accretion disk is measured very close in, at R_(in) = 1.7 \u00b1 0.4 R_g . Assuming R_(in_ = R_(ISCO), we find a relatively high black hole spin (a_* = 0.92 \u00b1 0.06). Imposing a lamppost geometry, we obtain a low inclination (i = 35\u00b0 \u00b1 4\u00b0), which agrees with the upper limit found in the radio (i < 49\u00b0). However, we note that this model cannot be statistically distinguished from a non-lamppost model with a free emissivity index, for which the inclination is markedly higher. Additionally, we find a relatively cool corona (57\u201370 keV) and large iron abundance (3.3\u20133.7 solar). We further find that properly accounting for Comptonization of the reflection emission improves the fit significantly and causes an otherwise low reflection fraction (~0.2\u20130.3) to increase by an order of magnitude, in line with geometrical expectations for a lamppost corona. We compare these results with similar investigations reported for GX 339\u22124 in its bright hard state.",
"date": "2018-09-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "864",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 25",
"id_number": "CaltechAUTHORS:20180827-144724340",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180827-144724340",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA Einstein Fellowship",
"grant_number": "PF5-160144"
},
{
"agency": "European Science Foundation"
},
{
"agency": "Ministry of Science, Research and the Arts (Baden-W\u00fcrttemberg)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aad231",
"primary_object": {
"basename": "1807_01949.pdf",
"url": "https://authors.library.caltech.edu/records/ajyj5-bw704/files/1807_01949.pdf"
},
"related_objects": [
{
"basename": "Garcia_2018_ApJ_864_25.pdf",
"url": "https://authors.library.caltech.edu/records/ajyj5-bw704/files/Garcia_2018_ApJ_864_25.pdf"
}
],
"pub_year": "2018",
"author_list": "Garc\u00eda, Javier A.; Steiner, James F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/g2c0w-jma56",
"eprint_id": 87517,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:15:00",
"lastmod": "2026-03-31 22:35:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hamaguchi-Kenji",
"name": {
"family": "Hamaguchi",
"given": "Kenji"
},
"orcid": "0000-0001-7515-2779"
},
{
"id": "Corcoran-M-F",
"name": {
"family": "Corcoran",
"given": "Michael F."
}
},
{
"id": "Pittard-J-M",
"name": {
"family": "Pittard",
"given": "Julian M."
},
"orcid": "0000-0003-2244-5070"
},
{
"id": "Sharma-N",
"name": {
"family": "Sharma",
"given": "Neetika"
}
},
{
"id": "Takahashi-Hiromitsu",
"name": {
"family": "Takahashi",
"given": "Hiromitsu"
},
"orcid": "0000-0001-6314-5897"
},
{
"id": "Russell-C-M-P",
"name": {
"family": "Russell",
"given": "Christopher M. P."
}
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Wik-D-R",
"name": {
"family": "Wik",
"given": "Daniel R."
},
"orcid": "0000-0001-8952-676X"
},
{
"id": "Gull-T-R",
"name": {
"family": "Gull",
"given": "Theodore R."
}
},
{
"id": "Richardson-N-D",
"name": {
"family": "Richardson",
"given": "Noel D."
},
"orcid": "0000-0002-2806-9339"
},
{
"id": "Madura-T-I",
"name": {
"family": "Madura",
"given": "Thomas I."
}
},
{
"id": "Moffat-A-F-J",
"name": {
"family": "Moffat",
"given": "Anthony F. J."
}
}
]
},
"title": "Non-thermal X-rays from colliding wind shock acceleration in the massive binary Eta Carinae",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2018 Macmillan Publishers Limited, part of Springer Nature. \n\nPublished: 02 July 2018. \n\nThis research has made use of data obtained from the High Energy Astrophysics Science Archive Research Center (HEASARC), provided by NASA's Goddard Space Flight Center. This research has made use of NASA's Astrophysics Data System Bibliographic Services. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. We appreciate M. Yukita, K. Madsen and M. Stuhlinger on helping resolve the NuSTAR and XMM-Newton data analysis. K.H. is supported by the Chandra grant GO4\u201315019A, GO7\u201318012A, the XMM-Newton grant NNX15AK62G, NNX16AN87G, NNX17AE67G, NNX17AE68G, and the ADAP grant NNX15AM96G. C.M.P.R. acknowledges initial support from Chandra Theory grant TM7-18003Z used in combination with an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by Universities Space Research Association under contract with NASA, and current support from FONDECYT grant 3170870. A.F.J.M. is supported by NSERC (Canada) and FQRNT (Quebec). \n\nAuthor Contributions: K.H. and M.F.C. led the project, from proposing and planning observations, analysing the data to composing the manuscript. J.M.P. constructed a theoretical model that explains the variation of the non-thermal component. N.S. performed initial analysis of the NuSTAR data in 2015. H.T analysed and discussed Fermi data of \u03b7 Car. C.M.P.R. performed theoretical simulations of \u03b7 Car's thermal X-ray emission. B.W.G. and D.R.W. discussed NuSTAR data analysis, especially the background characteristics. T.R.G. worked for the observation planning. T.R.G., N.D.R., T.I.M. and A.F.J.M. discussed the wind property of \u03b7 Car. All authors reviewed the manuscript and discussed the work. \n\nThe authors declare no competing interests. \n\nData availability: The raw data of the NuSTAR and XMM-Newton observations are available from the NASA HEASARC archive at https://heasarc.gsfc.nasa.gov.\n\nSubmitted - 1904.09219.pdf
Supplemental Material - 41550_2018_505_MOESM1_ESM.pdf
",
"abstract": "Cosmic-ray acceleration has been a long-standing mystery and, despite more than a century of study, we still do not have a complete census of acceleration mechanisms. The collision of strong stellar winds in massive binary systems creates powerful shocks that have been expected to produce high-energy cosmic rays through Fermi acceleration at the shock interface. The accelerated particles should collide with stellar photons or ambient material, producing non-thermal emission observable in X-rays and \u03b3-rays. The supermassive binary star Eta Carinae (\u03b7 Car) drives the strongest colliding wind shock in the solar neighbourhood. Observations with non-focusing high-energy observatories indicate a high-energy source near \u03b7 Car, but have been unable to conclusively identify \u03b7 Car as the source because of their relatively poor angular resolution. Here we present direct focussing observations of the non-thermal source in the extremely hard X-ray band, which is found to be spatially coincident with the star within several arc-seconds. These observations show that the source of non-thermal X-rays varies with the orbital phase of the binary, and that the photon index of the emission is similar to that derived through analysis of the \u03b3-ray spectrum. This is conclusive evidence that the high-energy emission indeed originates from non-thermal particles accelerated at colliding wind shocks.",
"date": "2018-09",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "2",
"number": "9",
"publisher": "Nature Publishing Group",
"pagerange": "731-736",
"id_number": "CaltechAUTHORS:20180702-110126214",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180702-110126214",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "GO4-15019A"
},
{
"agency": "NASA",
"grant_number": "GO7-18012A"
},
{
"agency": "NASA",
"grant_number": "NNX15AK62G"
},
{
"agency": "NASA",
"grant_number": "NNX16AN87G"
},
{
"agency": "NASA",
"grant_number": "NNX17AE67G"
},
{
"agency": "NASA",
"grant_number": "NNX17AE68G"
},
{
"agency": "NASA",
"grant_number": "NNX15AM96G"
},
{
"agency": "NASA Chandra",
"grant_number": "TM7-18003Z"
},
{
"agency": "NASA Postdoctoral Program"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "3170870"
},
{
"agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)"
},
{
"agency": "Fonds de recherche du Qu\u00e9bec - Nature et technologies (FRQNT)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41550-018-0505-1",
"primary_object": {
"basename": "1904.09219.pdf",
"url": "https://authors.library.caltech.edu/records/g2c0w-jma56/files/1904.09219.pdf"
},
"related_objects": [
{
"basename": "41550_2018_505_MOESM1_ESM.pdf",
"url": "https://authors.library.caltech.edu/records/g2c0w-jma56/files/41550_2018_505_MOESM1_ESM.pdf"
}
],
"pub_year": "2018",
"author_list": "Hamaguchi, Kenji; Corcoran, Michael F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/e0ft1-rpj02",
"eprint_id": 91582,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:01:49",
"lastmod": "2026-03-31 19:42:26",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Cook-W-R",
"name": {
"family": "Cook",
"given": "W. Rick"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kitaguchi-Takao",
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
}
]
},
"title": "Pushing the limits of the NuSTAR detectors",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nBG acknowledges valuable conversations with W. Rick Cook and Jill Burhnam during the development of this paper. This work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuS-TAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This work makes use of open source code produced by the community, including Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration, 2018) and the SciPy ecosystem. All graphics were produced using Veusz, Copyright (C) 2003-2018 Jeremy Sanders and contributors.\n\nPublished - 107092V.pdf
",
"abstract": "NuSTAR (the Nuclear Spectroscopic Telescope ARray) is a NASA Small Explorer (SMEX) mission launched in June of 2012. Since its launch, NuSTAR has been the preeminent instrument for spectroscopic analysis of the hard X-ray sky over the 3-80 keV bandpass. The low energy side of the bandpass is limited by the absorption along the photon path as well as by the ability of the pixels to trigger on incident photons. The on-board calibration source does not have a low-energy line that we can use to calibrate this part of the response, so instead we use the \"nearest-neighbor\" readout in the NuSTAR detector architecture to calibrate the individual pixel thresholds for all 8 flight detectors on both focal plane modules (FPMs). These threshold measurements feed back into the quantum efficiency of the detectors at low (<5 keV) energies and, once well-calibrated, may allow the use of NuSTAR data below the current 3 keV limit.",
"date": "2018-08-09",
"date_type": "published",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 107092V",
"id_number": "CaltechAUTHORS:20181207-145745237",
"isbn": "9781510619715",
"book_title": "High Energy, Optical, and Infrared Detectors for Astronomy VIII",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181207-145745237",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "Holland-A-D",
"name": {
"family": "Holland",
"given": "Andrew D."
}
},
{
"id": "Beletic-J",
"name": {
"family": "Beletic",
"given": "James"
}
}
]
},
"doi": "10.1117/12.2312844",
"primary_object": {
"basename": "107092V.pdf",
"url": "https://authors.library.caltech.edu/records/e0ft1-rpj02/files/107092V.pdf"
},
"pub_year": "2018",
"author_list": "Grefenstette, Brian W.; Cook, W. Rick; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kxgh5-n1e97",
"eprint_id": 88360,
"eprint_status": "archive",
"datestamp": "2023-08-19 11:00:21",
"lastmod": "2026-04-01 02:55:07",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Burnham-J-A",
"name": {
"family": "Burnham",
"given": "Jill A."
}
},
{
"id": "Cook-W-W",
"name": {
"family": "Cook",
"given": "Walter W."
}
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
}
]
},
"title": "Characterization of Redlen CZT detectors for x-ray astronomy",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "CZT, Redlen Technologies, X-ray detectors, NuSTAR, astronomy",
"note": "\u00a9 2018 Society of Photo-optical Instrumentation Engineers (SPIE). \n\nThis research was funded by NASA grant NNX13AC55G.\n\nPublished - 107091D.pdf
",
"abstract": "We present the results of ongoing characterization of Cadmium Zinc Telluride (CZT) semiconductors produced by Redlen Technologies for use in X-ray astronomy. The fully fabricated hybrid detectors consist of CZT crystals with a collecting area of 2 cm x 2 cm and thickness of 3mm mounted on a custom ASIC originally designed for the Nuclear Spectroscopic Telescope Array (NuSTAR) mission, which launched in 2012. We present the results of electronic noise, inter-pixel conductance, and leakage current tests as well as spectral calibration using an ^(241)Am source. Despite high electronic noise due to errors in fabrication, we are able to compare characteristics of the Redlen CZT detectors to those of the CZT detectors produced by eV Products aboard NuSTAR.",
"date": "2018-08-07",
"date_type": "published",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 107091D",
"id_number": "CaltechAUTHORS:20180730-135455343",
"isbn": "9781510619715",
"book_title": "High Energy, Optical, and Infrared Detectors for Astronomy VIII",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180730-135455343",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX13AC55G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "Holland-A-D",
"name": {
"family": "Holland",
"given": "Andrew D."
}
},
{
"id": "Beletic-J",
"name": {
"family": "Beletic",
"given": "James"
}
}
]
},
"doi": "10.1117/12.2313860",
"primary_object": {
"basename": "107091D.pdf",
"url": "https://authors.library.caltech.edu/records/kxgh5-n1e97/files/107091D.pdf"
},
"pub_year": "2018",
"author_list": "Pike, Sean N.; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zv5m2-mtx66",
"eprint_id": 86447,
"eprint_status": "archive",
"datestamp": "2023-08-19 10:40:26",
"lastmod": "2026-04-01 02:37:47",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Rana-V-R",
"name": {
"family": "Rana",
"given": "V."
},
"orcid": "0000-0003-1703-8796"
},
{
"id": "Tramper-F",
"name": {
"family": "Tramper",
"given": "F."
}
},
{
"id": "Webb-N-A",
"name": {
"family": "Webb",
"given": "N."
}
},
{
"id": "Kretschmar-P",
"name": {
"family": "Kretschmar",
"given": "P."
},
"orcid": "0000-0001-9840-2048"
}
]
},
"title": "A tale of two periods: determination of the orbital ephemeris of the super-Eddington pulsar NGC 7793 P13",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: neutron / X-rays: binaries / techniques: radial velocities / accretion / accretion disks / pulsars: individual: NGC 7793 P13",
"note": "\u00a9 ESO 2018. \n\nReceived 24 April 2018 / Accepted 17 May 2018. \n\nWe would like to thank the referee for the very helpful comments that helped to improve the manuscript. We thank M. K\u00fchnel and M. Nowak for the useful discussions. DJW and MJM acknowledge support from STFC Ernest Rutherford fellowships. This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the nustardas software package, jointly developed by ASDC (Italy) and Caltech (USA). This research has also made use of data obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States. This work has made use of data supplied by the UK Swift Science Data Centre at the University of Leicester, and also of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. This research has made use of a collection of ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/).\n\nPublished - aa33292-18.pdf
Accepted Version - 1805.05336.pdf
",
"abstract": "We present a timing analysis of multiple XMM-Newton and NuSTAR observations of the ultra-luminous pulsar NGC 7793 P13 spread over its 65 d variability period. We use the measured pulse periods to determine the orbital ephemeris, confirm a long orbital period with P_(orb) = 63.9^(+0.5)_(\u22120.6) d, and find an eccentricity of e \u2264 0.15. The orbital signature is imprinted on top of a secular spin-up, which seems to get faster as the source becomes brighter. We also analyze data from dense monitoring of the source with Swift and find an optical photometric period of 63.9 \u00b1 0.5 d and an X-ray flux period of 66.8 \u00b1 0.4 d. The optical period is consistent with the orbital period, while the X-ray flux period is significantly longer. We discuss possible reasons for this discrepancy, which could be due to a super-orbital period caused by a precessing accretion disk or an orbital resonance. We put the orbital period of P13 into context with the orbital periods implied for two other ultra-luminous pulsars, M82 X-2 and NGC 5907 ULX, and discuss possible implications for the system parameters.",
"date": "2018-08",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "616",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A186",
"id_number": "CaltechAUTHORS:20180517-190441870",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180517-190441870",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1051/0004-6361/201833292",
"primary_object": {
"basename": "1805.05336.pdf",
"url": "https://authors.library.caltech.edu/records/zv5m2-mtx66/files/1805.05336.pdf"
},
"related_objects": [
{
"basename": "aa33292-18.pdf",
"url": "https://authors.library.caltech.edu/records/zv5m2-mtx66/files/aa33292-18.pdf"
}
],
"pub_year": "2018",
"author_list": "F\u00fcrst, F.; Walton, D. J.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/qpr8n-r6t24",
"eprint_id": 88662,
"eprint_status": "archive",
"datestamp": "2023-08-19 10:32:59",
"lastmod": "2026-03-31 23:29:12",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lena-D",
"name": {
"family": "Lena",
"given": "D."
}
},
{
"id": "Panizo-Espinar-G",
"name": {
"family": "Panizo-Espinar",
"given": "G."
}
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
}
]
},
"title": "Characterization of a candidate dual AGN",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: interactions \u2013 galaxies: nuclei",
"note": "\u00a9 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices). \n\nAccepted 2018 April 30. Received 2018 April 30; in original form 2018 February 13. Published: 03 May 2018. \n\nThe authors thank K. L\u00f3pez-L\u00f3pez for carrying out the ACAM observations and the anonymous referee for valuable comments and suggestions. DL and PGJ acknowledge support from the European Research Council (ERC) under grant 647208 (PI Jonker). DL thanks the organizers and the participants of the Lorentz Center workshop 'The quest for multiple supermassive black holes: a multi-messenger view' for constructive and informative discussions; DL also thanks D. Merritt for constructive comments and C. Y. Peng and M. Cappellari for timely and clear assistance with the use of GALFIT and PPXF, respectively. MAPT acknowledges support via a Ram\u00f3n y Cajal Fellowship (RYC-2015-17854). \n\nThis research is based on observations made with the William Herschel Telescope, operated on the island of La Palma by the Isaac Newton Group of Telescopes in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof\u00edsica de Canarias. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This reasearch has also made use of data products from the Wide field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration.\n\nPublished - sty1147.pdf
Accepted Version - 1804.11232.pdf
",
"abstract": "We present Chandra and optical observations of a candidate dual active galactic nucleus (AGN) discovered serendipitously while searching for recoiling black holes via a cross-correlation between the serendipitous XMM source catalogue (2XMMi) and SDSS-DR7 galaxies with a separation no larger than 10 times the sum of their Petrosian radii. The system has a stellar mass ratio M_1/M_2 \u2248 0.7. One of the galaxies (Source 1) shows clear evidence for AGN activity in the form of hard X-ray emission and optical emission-line diagnostics typical of AGN ionization. The nucleus of the other galaxy (Source 2) has a soft X-ray spectrum, bluer colours, and optical emission-line ratios dominated by stellar photoionization with a 'composite' signature, which might indicate the presence of a weak AGN. When plotted on a diagram with X-ray luminosity versus [OIII] luminosity, both nuclei fall within the locus defined by local Seyfert galaxies. From the optical spectrum, we estimate the electron densities finding n_1 < 27 e\u2212\u2009cm^(\u22123) and n_2 \u2248 200 e\u2212\u2009cm^(\u22123). From a 2D decomposition of the surface brightness distribution, we infer that both galaxies host rotationally supported bulges (S\u00e9rsic index <1). While the active nature of Source 1 can be established with confidence, whether the nucleus of Source 2 is active remains a matter of debate. Evidence that a faint AGN might reside in its nucleus is, however, tantalizing.",
"date": "2018-07-21",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "478",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "1326-1340",
"id_number": "CaltechAUTHORS:20180808-132302455",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180808-132302455",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "Ram\u00f3n y Cajal Fellowship",
"grant_number": "RYC-2015-17854"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/sty1147",
"primary_object": {
"basename": "1804.11232.pdf",
"url": "https://authors.library.caltech.edu/records/qpr8n-r6t24/files/1804.11232.pdf"
},
"related_objects": [
{
"basename": "sty1147.pdf",
"url": "https://authors.library.caltech.edu/records/qpr8n-r6t24/files/sty1147.pdf"
}
],
"pub_year": "2018",
"author_list": "Lena, D.; Panizo-Espinar, G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jgbnh-1mt76",
"eprint_id": 88373,
"eprint_status": "archive",
"datestamp": "2023-08-19 10:21:36",
"lastmod": "2024-01-14 20:31:52",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ptak-A",
"name": {
"family": "Ptak",
"given": "Andrew F."
},
"orcid": "0000-0001-5655-1440"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Arcus: The X-ray Grating Spectrometer Explorer",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2018 Society of Photo-optical Instrumentation Engineers (SPIE).",
"abstract": "Arcus, a Medium Explorer (MIDEX) mission, was selected by NASA for a Phase A study in August 2017. The observatory provides high-resolution soft X-ray spectroscopy in the 12-50 \u00c5 bandpass with unprecedented sensitivity: effective areas of >350 cm^2 and spectral resolution >2500 at the energies of O VII and O VIII for z=0-0.3. The Arcus key science goals are (1) to measure the effects of structure formation imprinted upon the hot baryons that are predicted to lie in extended halos around galaxies, groups, and clusters, (2) to trace the propagation of outflowing mass, energy, and momentum from the vicinity of the black hole to extragalactic scales as a measure of their feedback and (3) to explore how stars, circumstellar disks and exoplanet atmospheres form and evolve. Arcus relies upon the same 12m focal length grazing-incidence silicon pore X-ray optics (SPO) that ESA has developed for the Athena mission; the focal length is achieved on orbit via an extendable optical bench. The focused X-rays from these optics are diffracted by high-efficiency Critical-Angle Transmission (CAT) gratings, and the results are imaged with flight-proven CCD detectors and electronics. The power and telemetry requirements on the spacecraft are modest. Arcus will be launched into an ~ 7 day 4:1 lunar resonance orbit, resulting in high observing efficiency, low particle background and a favorable thermal environment. Mission operations are straightforward, as most observations will be long (~100 ksec), uninterrupted, and pre-planned. The baseline science mission will be completed in <2 years, although the margin on all consumables allows for 5+ years of operation.",
"date": "2018-07-10",
"date_type": "published",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 1069926",
"id_number": "CaltechAUTHORS:20180731-102004948",
"isbn": "9781510619517",
"book_title": "Space Telescopes and Instrumentation 2018: Ultraviolet to Gamma Ray",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180731-102004948",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "den Herder-J-W-A",
"name": {
"family": "den Herder",
"given": "Jan-Willem A."
}
},
{
"id": "Nikzad-S",
"name": {
"family": "Nikzad",
"given": "Shouleh"
}
},
{
"id": "Nakazawa-Kazuhiro",
"name": {
"family": "Nakazawa",
"given": "Kazuhiro"
}
}
]
},
"doi": "10.1117/12.2313965",
"pub_year": "2018",
"author_list": "Ptak, Andrew F. and Madsen, Kristin K."
},
{
"id": "https://authors.library.caltech.edu/records/yqp1f-db065",
"eprint_id": 88367,
"eprint_status": "archive",
"datestamp": "2023-08-19 10:14:47",
"lastmod": "2026-03-31 23:12:35",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-Kristin-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Cook-W-R",
"name": {
"family": "Cook",
"given": "Walter R."
}
},
{
"id": "Forster-Karl",
"name": {
"family": "Forster",
"given": "Karl"
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-Brian-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Pike-Sean-N",
"name": {
"family": "Pike",
"given": "Sean N."
},
"orcid": "0000-0002-8403-0041"
}
]
},
"title": "Effective area calibration of the nuclear spectroscopic telescope array (NuSTAR)",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "NuSTAR, X-ray, Satellite",
"note": "\u00a9 2018 Society of Photo-optical Instrumentation Engineers (SPIE).\n\nPublished - 106991W.pdf
",
"abstract": "The Nuclear Spectroscopic Telescope ARray (NuSTAR) has been in orbit for 6 years, and with the calibration data accumulated over that period we have taken a new look at the effective area calibration. The NuSTAR 10-m focal length is achieved using an extendible mast, which flexes due to solar illumination. This results in individual observations sampling a range of off-axis angles rather than a particular off-axis angle. In our new approach, we have split over 50 individual Crab observations into segments at particular off-axis angles. We combine segments from different observations at the same off-axis angle to generate a new set of synthetic spectra, which we use to calibrate the vignetting function of the optics against the canonical Crab spectrum.",
"date": "2018-07-06",
"date_type": "published",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 106991W",
"id_number": "CaltechAUTHORS:20180731-083456479",
"isbn": "9781510619517",
"book_title": "Space Telescopes and Instrumentation 2018: Ultraviolet to Gamma Ray",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180731-083456479",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "den-Herder-Jan-Willem-A",
"name": {
"family": "den Herder",
"given": "Jan-Willem A."
}
},
{
"id": "Nikzad-Shouleh",
"name": {
"family": "Nikzad",
"given": "Shouleh"
}
},
{
"id": "Nakazawa-Kazuhiro",
"name": {
"family": "Nakazawa",
"given": "Kazuhiro"
}
}
]
},
"doi": "10.1117/12.2313675",
"primary_object": {
"basename": "106991W.pdf",
"url": "https://authors.library.caltech.edu/records/yqp1f-db065/files/106991W.pdf"
},
"pub_year": "2018",
"author_list": "Madsen, Kristin K.; Cook, Walter R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2we98-8d731",
"eprint_id": 88364,
"eprint_status": "archive",
"datestamp": "2023-08-19 10:14:37",
"lastmod": "2026-03-31 20:03:16",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "F. E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Hornschemeier-A-E",
"name": {
"family": "Hornschemeier",
"given": "Ann"
},
"orcid": "0000-0001-8667-2681"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "H."
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Okajima-Takashi",
"name": {
"family": "Okajima",
"given": "T."
}
},
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "S."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Saha-T-T",
"name": {
"family": "Saha",
"given": "T."
}
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "W."
},
"orcid": "0000-0002-1426-9698"
},
{
"id": "Pivovaroff-M-J",
"name": {
"family": "Pivovaroff",
"given": "M."
}
},
{
"id": "Vogel-J-K",
"name": {
"family": "Vogel",
"given": "J."
}
},
{
"id": "Descalle-M-A",
"name": {
"family": "Descalle",
"given": "M."
}
},
{
"id": "Broadway-D-M",
"name": {
"family": "Broadway",
"given": "D."
}
},
{
"id": "Gurgew-D",
"name": {
"family": "Gurgew",
"given": "D."
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Ferreira-D",
"name": {
"family": "Ferreira",
"given": "Desiree"
},
"orcid": "0000-0003-3243-9774"
},
{
"id": "Windt-D-L",
"name": {
"family": "Windt",
"given": "D."
}
}
]
},
"title": "Optical instrument design of the high-energy x-ray probe (HEX-P)",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "HEX-P, X-ray, Satellite",
"note": "\u00a9 2018 Society of Photo-optical Instrumentation Engineers (SPIE).\n\nPublished - 106996M.pdf
",
"abstract": "The High-Energy X-ray Probe (HEX-P) is a probe-class next-generation high-energy X-ray mission concept that will vastly extend the reach of broadband X-ray observations. Studying the 2-200 keV energy range, HEXP has 40 times the sensitivity of any previous mission in the 10-80 keV band, and will be the first focusing instrument in the 80-200 keV band. A successor to the Nuclear Spectroscopic Telescope Array (NuSTAR), a NASA Small Explorer launched in 2012, HEX-P addresses key NASA science objectives, and will serve as an important complement to ESA's L-class Athena mission. HEX-P will utilize multilayer coated X-ray optics, and in this paper we present the details of the optical design, and discuss the multilayer prescriptions necessary for the reflection of hard X-ray photons. We consider multiple module designs with the aim of investigating the tradeoff between high- and low-energy effective area, and review the technology development necessary to reach that goal within the next decade.",
"date": "2018-07-06",
"date_type": "published",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 106996M",
"id_number": "CaltechAUTHORS:20180730-154711488",
"isbn": "9781510619517",
"book_title": "Space Telescopes and Instrumentation 2018: Ultraviolet to Gamma Ray",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180730-154711488",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "den-Herder-J-W-A",
"name": {
"family": "den Herder",
"given": "Jan-Willem A."
}
},
{
"id": "Nikzad-S",
"name": {
"family": "Nikzad",
"given": "Shouleh"
}
},
{
"id": "Nakazawa-Kazuhiro",
"name": {
"family": "Nakazawa",
"given": "Kazuhiro"
}
}
]
},
"doi": "10.1117/12.2314117",
"primary_object": {
"basename": "106996M.pdf",
"url": "https://authors.library.caltech.edu/records/2we98-8d731/files/106996M.pdf"
},
"pub_year": "2018",
"author_list": "Madsen, Kristin K.; Christensen, F. E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zyewb-xrc17",
"eprint_id": 87282,
"eprint_status": "archive",
"datestamp": "2023-08-19 10:09:45",
"lastmod": "2026-03-31 20:17:24",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Jiang-Junle",
"name": {
"family": "Jiang",
"given": "J."
},
"orcid": "0000-0002-8796-5846"
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Alston-W-N",
"name": {
"family": "Alston",
"given": "W. N."
},
"orcid": "0000-0003-2658-6559"
},
{
"id": "Buisson-D-J-K",
"name": {
"family": "Buisson",
"given": "D. J. K."
}
},
{
"id": "Cackett-E-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Chiang-Chia-Ying",
"name": {
"family": "Chiang",
"given": "C.-Y."
},
"orcid": "0000-0002-9630-4003"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Gallo-L-C",
"name": {
"family": "Gallo",
"given": "L. C."
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "A. M."
}
},
{
"id": "De-Marco-B",
"name": {
"family": "De Marco",
"given": "B."
}
},
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Miniutti-G",
"name": {
"family": "Miniutti",
"given": "G."
}
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Wilkins-D-R",
"name": {
"family": "Wilkins",
"given": "D. R."
}
}
]
},
"title": "The 1.5\u2009Ms observing campaign on IRAS 13224\u22123809 \u2013 I. X-ray spectral analysis",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs\u2009\u2013\u2009black hole physics, galaxies: Seyfert, X-rays: galaxies",
"note": "\u00a9 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices) \n\nAccepted 2018 March 28. Received 2018 March 1; in original form 2017 September 11. \n\nJ.J. acknowledges support by the Cambridge Trust and the Chinese Scholarship Council Joint Scholarship Programme (201604100032). A.C.F., M.L.P., and C.P. acknowledge support by the ERC Advanced Grant 340442. B.D.M. acknowledges support by the Polish National Science Center grant Polonez 2016/21/P/ST9/04025. W.N.A. acknowledges support from the European Union Seventh Framework Program (FP7/2013\u20132017) under grant agreement no. 312789, StrongGravity. G.M. acknowledges support from the European Union Seventh Framework Program (FP7/2007\u20132013) under grant agreement no. 312789, StrongGravity and the Spanish grant ESP2015-65597-C4-1-R. D.J.K.B. is supported by the Science and Technology Facilities Council (STFC). J.A.G. acknowledges the support from the Alexander von Humboldt Foundation. D.R.W. is supported by NASA through Einstein Postdoctoral Fellowship grant number PF6-170160, awarded by the Chandra X-ray Center, operated by the Smithsonian Astrophysical Observatory for NASA under contract NAS8-03060. D.J.W. acknowledges support from an STFC Ernest Rutherford fellowship. Based on observations obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This project has made use of the Science Analysis Software (SAS), an extensive suite to process the data collected by the XMM\u2013Newton observatory. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center and the California Institute of Technology.\n\nPublished - sty836.pdf
Accepted Version - 1804.00349
",
"abstract": "We present a detailed spectral analysis of the recent 1.5\u2009Ms XMM\u2013Newton observing campaign on the narrow-line Seyfert 1 galaxy IRAS 13224\u22123809, taken simultaneously with 500\u2009ks of NuSTAR data. The X-ray light curve shows three flux peaks, registering at about 100 times the minimum flux seen during the campaign, and rapid variability with a time-scale of kiloseconds. The spectra are well fit with a primary power-law continuum, two relativistic-blurred reflection components from the inner accretion disc with very high iron abundance, and a simple blackbody-shaped model for the remaining soft excess. The spectral variability is dominated by the power-law continuum from a corona region within a few gravitational radii from the black hole. Additionally, blueshifted Ne\u2009X, Mg\u2009XII, Si\u2009XIV, and S\u2009XVI absorption lines are identified in the stacked low-flux spectrum, confirming the presence of a highly ionized outflow with velocity up to v = 0.267 and 0.225\u2009c. We fit the absorption features with xstar models and find a relatively constant velocity outflow through the whole observation. Finally, we replace the bbody and supersolar abundance reflection models by fitting the soft excess successfully with the extended reflection model relxillD, which allows for higher densities than the standard relxill model. This returns a disc electron density n_e > 10^(18.7)\u2009cm^(\u22123) and lowers the iron abundance from Z_(Fe) = 24^(+3)_(\u22124)Z_\u2299 with n-e = 10^(15) cm^(-3) to Z_(Fe) = 6.6^(+0.8)_(-2.1)Z_\u2299.",
"date": "2018-07-01",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "477",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3711-3726",
"id_number": "CaltechAUTHORS:20180620-154958509",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180620-154958509",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Cambridge Overseas Trust"
},
{
"agency": "Chinese Scholarship Council",
"grant_number": "201604100032"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2016/21/P/ST9/04025"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "312789"
},
{
"agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)",
"grant_number": "ESP2015-65597-C4-1-R"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA Einstein Fellowship",
"grant_number": "PF6-170160"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "ESA Member States"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/sty836",
"primary_object": {
"basename": "1804.00349",
"url": "https://authors.library.caltech.edu/records/zyewb-xrc17/files/1804.00349"
},
"related_objects": [
{
"basename": "sty836.pdf",
"url": "https://authors.library.caltech.edu/records/zyewb-xrc17/files/sty836.pdf"
}
],
"pub_year": "2018",
"author_list": "Jiang, J.; Parker, M. L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/2mp6d-4z718",
"eprint_id": 87607,
"eprint_status": "archive",
"datestamp": "2023-08-19 09:31:42",
"lastmod": "2023-10-18 21:18:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kocevski-D-D",
"name": {
"family": "Kocevski",
"given": "Dale D."
}
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
}
]
},
"title": "X-UDS: The Chandra Legacy Survey of the UKIDSS Ultra Deep Survey Field",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: nuclei \u2013 surveys \u2013 X-rays: galaxies",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2017 July 17; revised 2018 January 25; accepted 2018 January 29; published 2018 June 14. \n\nWe acknowledge the financial support from NASA Chandra grant GO5-16150B (D.D.K., G.H.). T.M. is supported by UNAM-DGAPA PAPIIT IN104216 and CONACyT 252531. M.B. acknowledges support from the FP7 Career Integration Grant \"eEASy\" (CIG 321913).\n\nPublished - Kocevski_2018_ApJS_236_48.pdf
Submitted - 1809.08240.pdf
",
"abstract": "We present the X-UDS survey, a set of wide and deep Chandra observations of the Subaru-XMM Deep/UKIDSS Ultra Deep Survey (SXDS/UDS) field. The survey consists of 25 observations that cover a total area of 0.33 deg^2. The observations are combined to provide a nominal depth of ~600 ks in the central 100 arcmin^2 region of the field that has been imaged with Hubble/WFC3 by the CANDELS survey and ~200 ks in the remainder of the field. In this paper, we outline the survey's scientific goals, describe our observing strategy, and detail our data reduction and point source detection algorithms. Our analysis has resulted in a total of 868 band-merged point sources detected with a false-positive Poisson probability of <1 \u00d7 10^(\u22124). In addition, we present the results of an X-ray spectral analysis and provide best-fitting neutral hydrogen column densities, N_H, as well as a sample of 51 Compton-thick active galactic nucleus candidates. Using this sample, we find the intrinsic Compton-thick fraction to be 30%\u201335% over a wide range in redshift (z = 0.1\u20133), suggesting the obscured fraction does not evolve very strongly with epoch. However, if we assume that the Compton-thick fraction is dependent on luminosity, as is seen for Compton-thin sources, then our results are consistent with a rise in the obscured fraction out to z ~ 3. Finally, an examination of the host morphologies of our Compton-thick candidates shows a high fraction of morphological disturbances, in agreement with our previous results. All data products described in this paper are made available via a public website.",
"date": "2018-06",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "236",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 48",
"id_number": "CaltechAUTHORS:20180706-135358776",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180706-135358776",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "GO5-16150B"
},
{
"agency": "Universidad Nacional Aut\u00f3noma de M\u00e9xico (UNAM)",
"grant_number": "IN104216"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "252531"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "321913 eEasy"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4365/aab9b4",
"primary_object": {
"basename": "1809.08240.pdf",
"url": "https://authors.library.caltech.edu/records/2mp6d-4z718/files/1809.08240.pdf"
},
"related_objects": [
{
"basename": "Kocevski_2018_ApJS_236_48.pdf",
"url": "https://authors.library.caltech.edu/records/2mp6d-4z718/files/Kocevski_2018_ApJS_236_48.pdf"
}
],
"pub_year": "2018",
"author_list": "Kocevski, Dale D. and Brightman, Murray"
},
{
"id": "https://authors.library.caltech.edu/records/av3yr-mdj98",
"eprint_id": 85431,
"eprint_status": "archive",
"datestamp": "2023-08-21 23:09:16",
"lastmod": "2026-04-01 00:00:00",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B. W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Kennea-J-A",
"name": {
"family": "Kennea",
"given": "J."
},
"orcid": "0000-0002-6745-4790"
},
{
"id": "Kosec-P",
"name": {
"family": "Kosec",
"given": "P."
}
},
{
"id": "Lau-Ryan-M",
"name": {
"family": "Lau",
"given": "R. M."
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Pinto-C",
"name": {
"family": "Pinto",
"given": "C."
},
"orcid": "0000-0003-2532-7379"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "J. F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Webb-N-A",
"name": {
"family": "Webb",
"given": "N."
}
}
]
},
"title": "A Potential Cyclotron Resonant Scattering Feature in the Ultraluminous X-Ray Source Pulsar NGC 300 ULX1 Seen by NuSTAR and XMM-Newton",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: neutron; X-rays: binaries; X-rays: individual (NGC 300 ULX1)",
"note": "\u00a9 2018. The American Astronomical Society. Received 2018 March 20; revised 2018 March 27; accepted 2018 March 29; published 2018 April 9. The authors would like to thank the reviewer for timely and positive feedback. D.J.W. and M.J.M. acknowledge support from STFC Ernest Rutherford fellowships. A.C.F. acknowledges ERC Advanced Grant 340442, P.K. acknowledges support from the STFC, and D.B. acknowledges support from the French Space Agency (CNES). This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). This work has also made use of data obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States. Facilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, XMM - Newton X-Ray Multimirror Mission satellite.\n\nPublished - Walton_2018_ApJL_857_L3.pdf
Submitted - 1803.07571.pdf
",
"abstract": "Based on phase-resolved broadband spectroscopy using XMM-Newton and NuSTAR, we report on a potential cyclotron resonant scattering feature (CRSF) at E ~ 13 keV in the pulsed spectrum of the recently discovered ultraluminous X-ray source (ULX) pulsar NGC 300 ULX1. If this interpretation is correct, the implied magnetic field of the central neutron star is B ~ 1012 G (assuming scattering by electrons), similar to that estimated from the observed spin-up of the star, and also similar to known Galactic X-ray pulsars. We discuss the implications of this result for the connection between NGC 300 ULX1 and the other known ULX pulsars, particularly in light of the recent discovery of a likely proton cyclotron line in another ULX, M51 ULX-8.",
"date": "2018-04-10",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "857",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L3",
"id_number": "CaltechAUTHORS:20180325-185226577",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180325-185226577",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "ESA Member States"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/2041-8213/aabadc",
"primary_object": {
"basename": "1803.07571.pdf",
"url": "https://authors.library.caltech.edu/records/av3yr-mdj98/files/1803.07571.pdf"
},
"related_objects": [
{
"basename": "Walton_2018_ApJL_857_L3.pdf",
"url": "https://authors.library.caltech.edu/records/av3yr-mdj98/files/Walton_2018_ApJL_857_L3.pdf"
}
],
"pub_year": "2018",
"author_list": "Walton, D. J.; Bachetti, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mmkvd-me150",
"eprint_id": 85327,
"eprint_status": "archive",
"datestamp": "2023-08-19 08:38:53",
"lastmod": "2026-04-01 00:01:18",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
}
]
},
"title": "Evidence for Pulsar-like Emission Components in the Broadband ULX Sample",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: neutron \u2013 X-rays: binaries \u2013 X-rays: individual (NGC 5907 ULX)",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2018 February 1; revised 2018 March 2; accepted 2018 March 8; published 2018 April 2. \n\nThe authors would like to thank the reviewer for positive feedback which helped to improve the final manuscript. D.J.W. and M.J.M. acknowledge support from STFC Ernest Rutherford fellowships, A.C.F. acknowledges support from ERC Advanced Grant 340442, and D.B. acknowledges financial support from the French Space Agency (CNES). This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). This work has also made use of data obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States, and with Suzaku, a collaborative mission between the space agencies of Japan (JAXA) and the USA (NASA). \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, XMM - Newton X-Ray Multimirror Mission satellite, Suzaku - Suzaku (ASTRO-EII).\n\nPublished - Walton_2018_ApJ_856_128.pdf
Submitted - 1803.04424.pdf
",
"abstract": "We present broadband X-ray analyses of a sample of bright ultraluminous X-ray sources (ULX) with the goal of investigating the spectral similarity of this population to the known ULX pulsars, M82 X-2, NGC 7793 P13, and NGC 5907 ULX. We perform a phase-resolved analysis of the broadband XMM-Newton+NuSTAR data set of NGC 5907 ULX, finding that the pulsed emission from the accretion column in this source exhibits a similar spectral shape to that seen in both M82 X-2 and NGC 7793 P13, and that this is responsible for the excess emission observed at the highest energies when the spectra are fit with accretion disk models. We then demonstrate that similar \"hard\" excesses are seen in all ULXs in the broadband sample. Finally, for ULXs where the nature of the accretor is currently unknown, we test whether the hard excesses are all consistent with being produced by an accretion column similar to those present in M82 X-2, NGC 7793 P13, and NGC 5907 ULX. Based on the average shape of the pulsed emission, we find that in all cases a similar accretion column can successfully reproduce the observed data, consistent with the hypothesis that this ULX sample may be dominated by neutron star accretors. Compared to the known pulsar ULXs, our spectral fits for the remaining ULXs suggest that the non-pulsed emission from the accretion flow beyond the magnetosphere makes a stronger relative contribution than the component associated with the accretion column. If these sources do also contain neutron star accretors, this may help to explain the lack of detected pulsations.",
"date": "2018-04-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "856",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 128",
"id_number": "CaltechAUTHORS:20180315-091957565",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180315-091957565",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aab610",
"primary_object": {
"basename": "1803.04424.pdf",
"url": "https://authors.library.caltech.edu/records/mmkvd-me150/files/1803.04424.pdf"
},
"related_objects": [
{
"basename": "Walton_2018_ApJ_856_128.pdf",
"url": "https://authors.library.caltech.edu/records/mmkvd-me150/files/Walton_2018_ApJ_856_128.pdf"
}
],
"pub_year": "2018",
"author_list": "Walton, D. J.; F\u00fcrst, F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zhqjs-vkg79",
"eprint_id": 85533,
"eprint_status": "archive",
"datestamp": "2023-08-19 08:39:51",
"lastmod": "2026-04-01 03:16:12",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kuhar-M",
"name": {
"family": "Kuhar",
"given": "Matej"
},
"orcid": "0000-0002-7210-180X"
},
{
"id": "Krucker-S",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
}
},
{
"id": "Glesener-L",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Hannah-I-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Smith-D-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
},
{
"id": "Hudson-H-S",
"name": {
"family": "Hudson",
"given": "Hugh S."
},
"orcid": "0000-0001-5685-1283"
},
{
"id": "White-S-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
}
]
},
"title": "NuSTAR Detection of X-Ray Heating Events in the Quiet Sun",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: flares \u2013 Sun: particle emission \u2013 Sun: X-rays, gamma rays",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2017 December 18; revised 2018 March 20; accepted 2018 March 21; published 2018 March 30. \n\nThis work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. M.K. and S.K. acknowledge funding from the Swiss National Science Foundation (200021-140308). I.G.H. is supported by a Royal Society University Research Fellowship. L.G. was supported by an NSF Faculty Development Grant (AGS-1429512). We thank the referee for the thorough reading of the manuscript and the helpful comments that substantially improved the paper.\n\nPublished - Kuhar_2018_ApJL_856_L32.pdf
Accepted Version - 1803.08365.pdf
",
"abstract": "The explanation of the coronal heating problem potentially lies in the existence of nanoflares, numerous small-scale heating events occurring across the whole solar disk. In this Letter, we present the first imaging spectroscopy X-ray observations of three quiet Sun flares during the Nuclear Spectroscopic Telescope ARray (NuSTAR) solar campaigns on 2016 July 26 and 2017 March 21, concurrent with the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) observations. Two of the three events showed time lags of a few minutes between peak X-ray and extreme ultraviolet emissions. Isothermal fits with rather low temperatures in the range 3.2\u20134.1 MK and emission measures of (0.6\u201315) \u00d7 10^(44) cm^(\u22123) describe their spectra well, resulting in thermal energies in the range (2\u20136) \u00d7 10^(26) erg. NuSTAR spectra did not show any signs of a nonthermal or higher temperature component. However, as the estimated upper limits of (hidden) nonthermal energy are comparable to the thermal energy estimates, the lack of a nonthermal component in the observed spectra is not a constraining result. The estimated Geostationary Operational Environmental Satellite (GOES) classes from the fitted values of temperature and emission measure fall between 1/1000 and 1/100 A class level, making them eight orders of magnitude fainter in soft X-ray flux than the largest solar flares.",
"date": "2018-04-01",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "856",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L32",
"id_number": "CaltechAUTHORS:20180330-111231496",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180330-111231496",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Swiss National Science Foundation (SNSF)",
"grant_number": "200021-140308"
},
{
"agency": "Royal Society"
},
{
"agency": "NSF",
"grant_number": "AGS-1429512"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/2041-8213/aab889",
"primary_object": {
"basename": "1803.08365.pdf",
"url": "https://authors.library.caltech.edu/records/zhqjs-vkg79/files/1803.08365.pdf"
},
"related_objects": [
{
"basename": "Kuhar_2018_ApJL_856_L32.pdf",
"url": "https://authors.library.caltech.edu/records/zhqjs-vkg79/files/Kuhar_2018_ApJL_856_L32.pdf"
}
],
"pub_year": "2018",
"author_list": "Kuhar, Matej; Krucker, S\u00e4m; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5kgmy-rfa06",
"eprint_id": 84975,
"eprint_status": "archive",
"datestamp": "2023-08-21 22:54:44",
"lastmod": "2026-03-31 19:40:58",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Yamaoka-Kazutaka",
"name": {
"family": "Yamaoka",
"given": "Kazutaka"
}
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "Didier"
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Chiu-Jeng-Lun",
"name": {
"family": "Chiu",
"given": "Jeng-Lun"
}
},
{
"id": "Clavel-M",
"name": {
"family": "Clavel",
"given": "Ma\u00efca"
},
"orcid": "0000-0003-0724-2742"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew"
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "Poshak"
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "Jon M."
}
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Alternative Explanations for Extreme Supersolar Iron Abundances Inferred from the Energy Spectrum of Cygnus X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks; black hole physics; stars: individual (Cygnus X-1); X-rays: general; X-rays: stars",
"note": "\u00a9 2018 American Astronomical Society. \n\nReceived 2017 December 1. Accepted 2018 January 22. Published 2018 February 27. \n\nThis work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). This research has made use of data obtained from the Suzaku satellite, a collaborative mission between the space agencies of Japan (JAXA) and the USA (NASA). J.A.T. acknowledges partial support from NuSTAR Guest Observer grant NNX15AV23G. A.C.F. acknowledges support from ERC Advanced Grant 340442. D.J.W. acknowledges support from STFC in the form of an Ernest Rutherford fellowship. J.A.T. thanks K. Hamaguchi for help with the XIS data reduction and T. Dauser, K. Koljonen, and A. Zoghbi for useful discussions. This research has made use of the MAXI data provided by RIKEN, JAXA, and the MAXI team.\n\nPublished - Tomsick_2018_ApJ_855_3.pdf
Submitted - 1801.07267.pdf
",
"abstract": "Here we study a 1\u2013200 keV energy spectrum of the black hole binary Cygnus X-1 taken with NuSTAR and Suzaku. This is the first report of a NuSTAR observation of Cyg X-1 in the intermediate state, and the observation was taken during the part of the binary orbit where absorption due to the companion's stellar wind is minimal. The spectrum includes a multi-temperature thermal disk component, a cutoff power-law component, and relativistic and nonrelativistic reflection components. Our initial fits with publicly available constant density reflection models (relxill and reflionx) lead to extremely high iron abundances (>9.96 and 10.6_(-0.9)^(+1.6) times solar, respectively). Although supersolar iron abundances have been reported previously for Cyg X-1, our measurements are much higher and such variability is almost certainly unphysical. Using a new version of reflionx that we modified to make the electron density a free parameter, we obtain better fits to the spectrum even with solar iron abundances. We report on how the higher density (n_e = (3.98)_(-0.25)^(+0.12)) x 10^(20) cm^(\u22123)) impacts other parameters such as the inner radius and inclination of the disk.",
"date": "2018-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "855",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 3",
"id_number": "CaltechAUTHORS:20180227-133907106",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180227-133907106",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NNX15AV23G"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aaaab1",
"primary_object": {
"basename": "1801.07267.pdf",
"url": "https://authors.library.caltech.edu/records/5kgmy-rfa06/files/1801.07267.pdf"
},
"related_objects": [
{
"basename": "Tomsick_2018_ApJ_855_3.pdf",
"url": "https://authors.library.caltech.edu/records/5kgmy-rfa06/files/Tomsick_2018_ApJ_855_3.pdf"
}
],
"pub_year": "2018",
"author_list": "Tomsick, John A.; Parker, Michael L.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0ewab-36g27",
"eprint_id": 85203,
"eprint_status": "archive",
"datestamp": "2023-08-19 08:12:25",
"lastmod": "2026-03-31 20:27:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wang-Ji-Jingyi",
"name": {
"family": "Wang-Ji",
"given": "Jingyi"
}
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Steiner-J-F",
"name": {
"family": "Steiner",
"given": "James F."
},
"orcid": "0000-0002-5872-6061"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Bambi-C",
"name": {
"family": "Bambi",
"given": "Cosimo"
},
"orcid": "0000-0002-3180-9502"
},
{
"id": "Petrucci-Pierre-Olivier",
"name": {
"family": "Petrucci",
"given": "Pierre-Olivier"
}
},
{
"id": "Ferreira-J",
"name": {
"family": "Ferreira",
"given": "Jonathan"
}
},
{
"id": "Chakravorty-S",
"name": {
"family": "Chakravorty",
"given": "Susmita"
}
},
{
"id": "Clavel-M",
"name": {
"family": "Clavel",
"given": "Ma\u00efca"
},
"orcid": "0000-0003-0724-2742"
}
]
},
"title": "The Evolution of GX 339-4 in the Low-hard State as Seen by NuSTAR and Swift",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 black hole physics \u2013 line: formation \u2013 X-rays: individual (GX 339\u20134)",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2017 November 15; revised 2018 January 9; accepted 2018 January 19; published 2018 March 8. \n\nPart of this work was carried out by JW during attendance to the Summer Undergraduate Research Fellowship (SURF) at California Institute of Technology in 2017. Warm hospitality and tutelage are kindly acknowledged, in particular from the members of the NuSTAR Science Operations Team (K. Foster, B. Grenfestette, K. Madsen, M. Heida, M. Brightman, and D. Stern). We would like to thank the referee for useful comments toward the improvement of this paper. We also thank B. de Marco and G. Ponti for useful discussions. J.A.G. acknowledges support from NASA grants NNX17AJ65G and 80NSSC177K0515, and from the Alexander von Humboldt Foundation. J.F.S. has been supported by NASA Hubble Fellowship grant HST-HF-51315.01. S.C. is supported by the SERB National Postdoctoral Fellowship (No. PDF/2017/000841). We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations.\n\nPublished - Wang-Ji_2018_ApJ_855_61.pdf
Accepted Version - 1712.02571.pdf
",
"abstract": "We analyze 11 Nuclear Spectroscopic Telescope Array and Swift observations of the black hole X-ray binary GX 339\u20134 in the hard state, 6 of which were taken during the end of the 2015 outburst and 5 during a failed outburst in 2013. These observations cover luminosities from 0.5% to 5% of the Eddington luminosity. Implementing the most recent version of the reflection model relxillCp, we perform simultaneous spectral fits on both data sets to track the evolution of the properties in the accretion disk, including the inner edge radius, the ionization, and the temperature of the thermal emission. We also constrain the photon index and electron temperature of the primary source (the \"corona\"). We observe a maximum truncation radius of 37 R_g in the preferred fit for the 2013 data set, and a marginal correlation between the level of truncation and luminosity. We also explore a self-consistent model under the framework of coronal Comptonization, and find consistent results regarding the disk truncation in the 2015 data, providing a more physical preferred fit for the 2013 observations.",
"date": "2018-03-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "855",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 61",
"id_number": "CaltechAUTHORS:20180308-105914434",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180308-105914434",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Caltech Summer Undergraduate Research Fellowship (SURF)"
},
{
"agency": "NASA",
"grant_number": "NNX17AJ65G"
},
{
"agency": "NASA",
"grant_number": "80NSSC177K0515"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA Hubble Fellowship",
"grant_number": "HST-HF-51315.01"
},
{
"agency": "Science and Engineering Research Board (SERB)",
"grant_number": "PDF/2017/000841"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aaa974",
"primary_object": {
"basename": "1712.02571.pdf",
"url": "https://authors.library.caltech.edu/records/0ewab-36g27/files/1712.02571.pdf"
},
"related_objects": [
{
"basename": "Wang-Ji_2018_ApJ_855_61.pdf",
"url": "https://authors.library.caltech.edu/records/0ewab-36g27/files/Wang-Ji_2018_ApJ_855_61.pdf"
}
],
"pub_year": "2018",
"author_list": "Wang-Ji, Jingyi; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/3q2ca-b0j09",
"eprint_id": 85206,
"eprint_status": "archive",
"datestamp": "2023-08-21 22:52:09",
"lastmod": "2026-03-31 23:36:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Masini-A",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Civano-Francesca",
"name": {
"family": "Civano",
"given": "F."
},
"orcid": "0000-0002-2115-1137"
},
{
"id": "Comastri-A",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Fornasini-F",
"name": {
"family": "Fornasini",
"given": "F."
},
"orcid": "0000-0002-9286-9963"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Lansbury-G-B",
"name": {
"family": "Lansbury",
"given": "G. B."
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Treister-E",
"name": {
"family": "Treister",
"given": "E."
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Alexander-D-M",
"name": {
"family": "Alexander",
"given": "D. M."
},
"orcid": "0000-0002-5896-6313"
},
{
"id": "Boorman-P-G",
"name": {
"family": "Boorman",
"given": "P. G."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Brandt-W-N",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "Farrah-D",
"name": {
"family": "Farrah",
"given": "D."
},
"orcid": "0000-0003-1748-2010"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Hickox-R-C",
"name": {
"family": "Hickox",
"given": "R. C."
},
"orcid": "0000-0003-1468-9526"
},
{
"id": "Kocevski-D-D",
"name": {
"family": "Kocevski",
"given": "D. D."
}
},
{
"id": "Lanz-L",
"name": {
"family": "Lanz",
"given": "L."
},
"orcid": "0000-0002-3249-8224"
},
{
"id": "Marchesi-S",
"name": {
"family": "Marchesi",
"given": "S."
},
"orcid": "0000-0001-5544-0749"
},
{
"id": "Puccetti-S",
"name": {
"family": "Puccetti",
"given": "S."
},
"orcid": "0000-0002-2734-7835"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Saez-C",
"name": {
"family": "Saez",
"given": "C."
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zappacosta-L",
"name": {
"family": "Zappacosta",
"given": "L."
},
"orcid": "0000-0002-4205-6884"
}
]
},
"title": "The NuSTAR Extragalactic Surveys: Source Catalog and the Compton-thick Fraction in the UDS Field",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active; galaxies: evolution; X-rays: general",
"note": "\u00a9 2018 American Astronomical Society. \n\nReceived 2017 September 13. Accepted 2018 January 4. Published 2018 March 8. \n\nWe thank the anonymous referee for providing helpful comments, which significantly improved the clarity and robustness of the paper. \n\nThis work was supported under NASA contract NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nThis research has also made use of data obtained from the Chandra Data Archive and the Chandra Source Catalog, software provided by the Chandra X-ray Center (CXC), and observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, together with data obtained from the 3XMM XMM-Newton serendipitous source catalog compiled by the 10 institutes of the XMM-Newton Survey Science Centre selected by ESA. \n\nA.M. and A.C. acknowledge support from the ASI/INAF grant I/037/12/0011/13. W.N.B. acknowledges Caltech NuSTAR subcontract 44A-1092750. L.Z. acknowledges financial support under ASI/INAF contract I/037/12/0. G.B.L. acknowledges support from a Herchel Smith Fellowship of the University of Cambridge. E.T. acknowledges support from CONICYT-Chile grants Basal-CATA PFB-06/2007 and FONDECYT Regular 1160999. R.C.H. acknowledges support from NASA through grant no. NNX15AP24G. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Chandra - , XMM-Newton. -\n\nPublished - Masini_2018_ApJS_235_17.pdf
Submitted - 1801.01881.pdf
",
"abstract": "We present the results and the source catalog of the NuSTAR survey in the UKIDSS Ultra Deep Survey (UDS) field, bridging the gap in depth and area between NuSTAR's ECDFS and COSMOS surveys. The survey covers a ~0.6 deg2 area of the field for a total observing time of ~1.75 Ms, to a half-area depth of ~155 ks corrected for vignetting at 3\u201324 keV, and reaching sensitivity limits at half-area in the full (3\u201324 keV), soft (3\u20138 keV), and hard (8\u201324 keV) bands of 2.2 \u00d7 10\u221214 erg cm\u22122 s\u22121, 1.0 \u00d7 10\u221214 erg cm\u22122 s\u22121, and 2.7 \u00d7 10\u221214 erg cm\u22122 s\u22121, respectively. A total of 67 sources are detected in at least one of the three bands, 56 of which have a robust optical redshift with a median of $\\langle z\\rangle \\sim 1.1$. Through a broadband (0.5\u201324 keV) spectral analysis of the whole sample combined with the NuSTAR hardness ratios, we compute the observed Compton-thick (CT; N H > 1024 cm\u22122) fraction. Taking into account the uncertainties on each N H measurement, the final number of CT sources is 6.8 \u00b1 1.2. This corresponds to an observed CT fraction of 11.5% \u00b1 2.0%, providing a robust lower limit to the intrinsic fraction of CT active galactic nuclei and placing constraints on cosmic X-ray background synthesis models.",
"date": "2018-03",
"date_type": "published",
"publication": "Astrophysical Journal Supplement Series",
"volume": "235",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 17",
"id_number": "CaltechAUTHORS:20180308-120302328",
"issn": "1538-4365",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180308-120302328",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0-011/13"
},
{
"agency": "Caltech NuSTAR subcontract",
"grant_number": "44A-1092750"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0"
},
{
"agency": "Herchel Smith Foundation"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "Basal-CATA PFB-06/2007"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1160999"
},
{
"agency": "NASA",
"grant_number": "NNX15AP24G"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4365/aaa83d",
"primary_object": {
"basename": "1801.01881.pdf",
"url": "https://authors.library.caltech.edu/records/3q2ca-b0j09/files/1801.01881.pdf"
},
"related_objects": [
{
"basename": "Masini_2018_ApJS_235_17.pdf",
"url": "https://authors.library.caltech.edu/records/3q2ca-b0j09/files/Masini_2018_ApJS_235_17.pdf"
}
],
"pub_year": "2018",
"author_list": "Masini, A.; Civano, F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/swp2a-ted79",
"eprint_id": 84230,
"eprint_status": "archive",
"datestamp": "2023-08-19 08:29:36",
"lastmod": "2026-03-31 23:57:20",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "Murray"
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
}
]
},
"title": "Magnetic field strength of a neutron-star-powered ultraluminous X-ray source",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2018 Macmillan Publishers. \n\nReceived: 05 December 2017. Accepted: 16 January 2018. Published online: 26 February 2018. \n\nM.J.M. and D.J.W. appreciate support from Ernest Rutherford Science and Technology Facilities Council fellowships. The work of D.S. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. \n\nAuthor Contributions: M. Brightman reduced and analysed the Chandra and XMM-Newton data. F.F. performed timing analysis of the Chandra and XMM-Newton data. M.H. analysed the ULX multiwavelength counterpart. M. Brightman, F.A.H., F.F., M.J.M., D.J.W., A.C.F., D.B. and M. Bachetti interpreted the results. M. Brightman, F.A.H., D.J.W. and D.S. prepared the manuscript. \n\nThe authors declare no competing interests.\n\nAccepted Version - 1803.02376
",
"abstract": "Ultraluminous X-ray sources (ULXs) are bright X-ray sources in nearby galaxies not associated with the central supermassive black hole. Their luminosities imply they are powered by either an extreme accretion rate onto a compact stellar remnant, or an intermediate mass (~100\u201310^5M_\u2299) black hole. Recently detected coherent pulsations coming from three bright ULXs demonstrate that some of these sources are powered by accretion onto a neutron star, implying accretion rates significantly in excess of the Eddington limit, a high degree of geometric beaming, or both. The physical challenges associated with the high implied accretion rates can be mitigated if the neutron star surface field is very high (10^(14)\u2009G), since this suppresses the electron scattering cross-section, reducing the radiation pressure that chokes off accretion for high luminosities. Surface magnetic field strengths can be determined through cyclotron resonance scattering features produced by the transition of charged particles between quantized Landau levels. Here, we present the detection at a significance of 3.8\u03c3 of an absorption line at 4.5\u2009keV in the Chandra spectrum of a ULX in M51. This feature is likely to be a cyclotron resonance scattering feature produced by the strong magnetic field of a neutron star. Assuming scattering off electrons, the magnetic field strength is implied to be ~10^(11)\u2009G, while protons would imply a magnetic field of B\u2009~\u200910^(15)\u2009G.",
"date": "2018-02-26",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "2",
"number": "4",
"publisher": "Nature Publishing Group",
"pagerange": "312-316",
"id_number": "CaltechAUTHORS:20180110-105628140",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180110-105628140",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1038/s41550-018-0391-6",
"primary_object": {
"basename": "1803.02376",
"url": "https://authors.library.caltech.edu/records/swp2a-ted79/files/1803.02376"
},
"pub_year": "2018",
"author_list": "Brightman, Murray; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/wx8p5-k1t59",
"eprint_id": 84740,
"eprint_status": "archive",
"datestamp": "2023-08-21 22:46:00",
"lastmod": "2025-06-30 18:13:29",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zappacosta-L",
"name": {
"family": "Zappacosta",
"given": "L."
},
"orcid": "0000-0002-4205-6884"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "The NuSTAR Extragalactic Surveys: X-Ray Spectroscopic Analysis of the Bright Hard-band Selected Sample",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active; surveys; X-rays: galaxies",
"note": "\u00a9 2018 American Astronomical Society. \n\nReceived 2017 May 24. Accepted 2017 December 29. Published 2018 February 8. \n\nWe thank the anonymous referee for useful comments that helped improve our analysis and the presentation of our results. We thank Johannes Buchner and Yoshihiro Ueda for providing machine-readable results on the absorbed fractions. L.Z. thanks R. Gilli, F. Nicastro, E. Piconcelli, R. Valiante, F. Vito, and D. Burlon for useful discussions. L.Z., A.C., F.F., G.L., and A.M. acknowledge financial support under ASI/INAF contract I/037/12/0. A.C. acknowledges the Caltech Kingsley fellowship program. G.L. acknowledges financial support from the CIG grant eEASY No. 321913. F.E.B. acknowledges support from CONICYT-Chile (Basal-CATA PFB-06/2007, FONDECYT Regular 1141218), the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. This work was supported under NASA Contract NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Zappacosta_2018_ApJ_854_33.pdf
",
"abstract": "We discuss the spectral analysis of a sample of 63 active galactic nuclei (AGN) detected above a limiting flux of S(8-24 keV) = 7 x 10^(-14) erg s^(-1) cm^(-2 in the multi-tiered NuSTAR extragalactic survey program. The sources span a redshift range z = 0-2.1 (median (z) = 0.58). The spectral analysis is performed over the broad 0.5\u201324 keV energy range, combining NuSTAR with Chandra and/or XMM-Newton data and employing empirical and physically motivated models. This constitutes the largest sample of AGN selected at \u3009 10 keV to be homogeneously spectrally analyzed at these flux levels. We study the distribution of spectral parameters such as photon index, column density (N_H), reflection parameter (R), and 10\u201340 keV luminosity (L_X). Heavily obscured (log[N_H/cm^(-2] \u2265 23) and Compton-thick (CT; log[N_H/cm^(-2)] \u2265 24) AGN constitute ~25% (15\u201317 sources) and ~2\u20133% (1\u20132 sources) of the sample, respectively. The observed N_H distribution agrees fairly well with predictions of cosmic X-ray background population-synthesis models (CXBPSM). We estimate the intrinsic fraction of AGN as a function of N_H, accounting for the bias against obscured AGN in a flux-selected sample. The fraction of CT AGN relative to log[N_H/cm^(-2] = 20-24 AGN is poorly constrained, formally in the range 2\u201356% (90% upper limit of 66%). We derived a fraction (f_(abs)) of obscured AGN (log[N_H/cm^(-2]= 22-24) as a function of L_X in agreement with CXBPSM and previous z \u3008 1 X-ray determinations. Furthermore, f_(abs) at z = 0.1-0.5 and log(L_x/erg s^(-1) \u2248 43.6-44.3 agrees with observational measurements/trends obtained over larger redshift intervals. We report a significant anti-correlation of R with L_X (confirmed by our companion paper on stacked spectra) with considerable scatter around the median R values.",
"date": "2018-02-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "854",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 33",
"id_number": "CaltechAUTHORS:20180208-112709097",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180208-112709097",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0-011/13"
},
{
"agency": "Caltech Kingsley fellowship"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "321913 eEasy"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "Basal-CATA PFB-06/2007"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1141218"
},
{
"agency": "Ministry of Economy, Development and Tourism's Millennium Science Initiative",
"grant_number": "IC120009"
},
{
"agency": "Millennium Institute of Astrophysics (MAS)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL"
},
{
"agency": "Istituto Nazionale di Astrofisica (INAF)"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aaa550",
"primary_object": {
"basename": "Zappacosta_2018_ApJ_854_33.pdf",
"url": "https://authors.library.caltech.edu/records/wx8p5-k1t59/files/Zappacosta_2018_ApJ_854_33.pdf"
},
"pub_year": "2018",
"author_list": "Zappacosta, L. and Harrison, F. A."
},
{
"id": "https://authors.library.caltech.edu/records/mrm40-ety75",
"eprint_id": 78032,
"eprint_status": "archive",
"datestamp": "2023-08-19 07:40:03",
"lastmod": "2026-03-31 22:17:07",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Risaliti-G",
"name": {
"family": "Risaliti",
"given": "G."
}
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "A."
}
},
{
"id": "Matt-G",
"name": {
"family": "Matt",
"given": "G."
},
"orcid": "0000-0002-2152-0916"
},
{
"id": "Miniutti-G",
"name": {
"family": "Miniutti",
"given": "G."
}
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "M. L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
}
]
},
"title": "Disentangling the Complex Broadband X-ray Spectrum of IRAS 13197-1627 with NuSTAR, XMM-Newton and Suzaku",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: active \u2013 X-rays: individual: IRAS 13197\u22121627",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. \n\nAccepted 2017 October 9. Received 2017 October 9; in original form 2017 June 7. Published: 12 October 2017. \n\nThe authors would like to thank the reviewer for their helpful feedback, which helped to improve the final version of the manuscript. DJW acknowledges support from an STFC Ernest Rutherford Fellowship, and ACF acknowledges support from ERC Advanced Grant 340442. GM thanks the European Union Seventh Framework Program (FP7/2007\u20132013) for funding under grant 312789 (StrongGravity). This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). This research has also made use of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States, and with Suzaku, a collaborative mission between the space agencies of Japan (JAXA) and the USA (NASA).\n\nPublished - stx2659.pdf
Accepted Version - 1706.02088.pdf
",
"abstract": "We present results from a coordinated XMM\u2013Newton+NuSTAR observation of the type 1.8 Seyfert galaxy IRAS\u200913197\u22121627. This is a highly complex source, with strong contributions from relativistic reflection from the inner accretion disc, neutral absorption and further reprocessing by more distant material, and ionized absorption from an outflow. We undertake a detailed spectral analysis combining the broad-band coverage provided by XMM\u2013Newton+NuSTAR with a multi-epoch approach incorporating archival observations performed by XMM\u2013Newton and Suzaku. Our focus is on characterizing the reflection from the inner accretion disc, which previous works have suggested may dominate the AGN emission, and constraining the black hole spin. Using lamppost disc reflection models, we find that the results for the inner disc are largely insensitive to assumptions regarding the geometry of the distant reprocessor and the precise form of the illuminating X-ray continuum. However, these results do depend on the treatment of the iron abundance of the distant absorber/reprocessor. The multi-epoch data favour a scenario in which the AGN is chemically homogeneous, and we find that a rapidly rotating black hole is preferred, with a* \u2265 0.7, but a slowly rotating black hole is not strongly excluded. In addition to the results for the inner disc, we also find that both the neutral and ionized absorbers vary from epoch to epoch, implying that both have some degree of inhomogeneity in their structure.",
"date": "2018-02-01",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "473",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "4377-4391",
"id_number": "CaltechAUTHORS:20170608-112508378",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170608-112508378",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "312789"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stx2659",
"primary_object": {
"basename": "stx2659.pdf",
"url": "https://authors.library.caltech.edu/records/mrm40-ety75/files/stx2659.pdf"
},
"related_objects": [
{
"basename": "1706.02088.pdf",
"url": "https://authors.library.caltech.edu/records/mrm40-ety75/files/1706.02088.pdf"
}
],
"pub_year": "2018",
"author_list": "Walton, D. J.; Brightman, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/001ky-t6t08",
"eprint_id": 84908,
"eprint_status": "archive",
"datestamp": "2023-08-19 07:41:27",
"lastmod": "2026-04-01 02:57:09",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "M."
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "Barret-D",
"name": {
"family": "Barret",
"given": "D."
},
"orcid": "0000-0002-0393-9190"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Middleton-M-J",
"name": {
"family": "Middleton",
"given": "M. J."
},
"orcid": "0000-0002-8183-2970"
},
{
"id": "Ptak-A",
"name": {
"family": "Ptak",
"given": "A."
},
"orcid": "0000-0001-5655-1440"
},
{
"id": "Tao-Lian",
"name": {
"family": "Tao",
"given": "L."
}
}
]
},
"title": "Super-Eddington accretion on to the neutron star NGC 7793 P13: Broad-band X-ray spectroscopy and ultraluminous X-ray sources",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: neutron \u2013 X-rays: binaries \u2013 X-rays: individual: NGC7793 P13",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.\n\nAccepted 2017 October 9. Received 2017 October 9; in original form 2017 May 29. Published: 11 October 2017.\n\nThe authors would like to thank the reviewer for the feedback provided, which helped to improve the final version of the manuscript. DJW and MJM acknowledge support from an STFC Ernest Rutherford fellowship, ACF acknowledges support from ERC Advanced Grant 340442 and DB acknowledges financial support from the French Space Agency (CNES). This research has made use of data obtained with NuSTAR, a project led by Caltech, funded by NASA and managed by NASA/JPL, and has utilized the NUSTARDAS software package, jointly developed by the ASDC (Italy) and Caltech (USA). This work has also made use of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States.\n\nPublished - stx2650.pdf
Accepted Version - 1705.10297.pdf
",
"abstract": "We present a detailed, broad-band X-ray spectral analysis of the ultraluminous X-ray source (ULX) pulsar NGC\u20097793 P13, a known super-Eddington source, utilizing data from the XMM\u2013Newton, NuSTAR and Chandra observatories. The broad-band XMM\u2013Newton+NuSTAR spectrum of P13 is qualitatively similar to the rest of the ULX sample with broad-band coverage, suggesting that additional ULXs in the known population may host neutron star accretors. Through time-averaged, phase-resolved and multi-epoch studies, we find that two non-pulsed thermal blackbody components with temperatures \u223c0.5 and 1.5\u2009keV are required to fit the data below 10\u2009keV, in addition to a third continuum component which extends to higher energies and is associated with the pulsed emission from the accretion column. The characteristic radii of the thermal components appear to be comparable, and are too large to be associated with the neutron star itself, so the need for two components likely indicates the accretion flow outside the magnetosphere is complex. We suggest a scenario in which the thick inner disc expected for super-Eddington accretion begins to form, but is terminated by the neutron star's magnetic field soon after its onset, implying a limit of B \u2272 6 \u00d7 10^(12)\u2009G for the dipolar component of the central neutron star's magnetic field. Evidence of similar termination of the disc in other sources may offer a further means of identifying additional neutron star ULXs. Finally, we examine the spectrum exhibited by P13 during one of its unusual 'off' states. These data require both a hard power-law component, suggesting residual accretion on to the neutron star, and emission from a thermal plasma, which we argue is likely associated with the P13 system.",
"date": "2018-02-01",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "473",
"number": "4",
"publisher": "Royal Astronomical Society",
"pagerange": "4360-4376",
"id_number": "CaltechAUTHORS:20180221-134250534",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180221-134250534",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stx2650",
"primary_object": {
"basename": "1705.10297.pdf",
"url": "https://authors.library.caltech.edu/records/001ky-t6t08/files/1705.10297.pdf"
},
"related_objects": [
{
"basename": "stx2650.pdf",
"url": "https://authors.library.caltech.edu/records/001ky-t6t08/files/stx2650.pdf"
}
],
"pub_year": "2018",
"author_list": "Walton, D. J.; F\u00fcrst, F.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/zjvy9-1ny89",
"eprint_id": 81696,
"eprint_status": "archive",
"datestamp": "2023-08-19 07:21:38",
"lastmod": "2026-03-31 20:46:38",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ponti-G",
"name": {
"family": "Ponti",
"given": "G."
},
"orcid": "0000-0003-0293-3608"
},
{
"id": "Bianchi-S",
"name": {
"family": "Bianchi",
"given": "S."
},
"orcid": "0000-0002-4622-4240"
},
{
"id": "Mu\u00f1os-Darias-T",
"name": {
"family": "Mu\u00f1os-Darias",
"given": "T."
}
},
{
"id": "Mori-Kaya",
"name": {
"family": "Mori",
"given": "K."
},
"orcid": "0000-0002-9709-5389"
},
{
"id": "De-Kishalay",
"name": {
"family": "De",
"given": "K."
},
"orcid": "0000-0002-8989-0542"
},
{
"id": "Rau-A",
"name": {
"family": "Rau",
"given": "A."
},
"orcid": "0000-0001-5990-6243"
},
{
"id": "De-Marco-B",
"name": {
"family": "De Marco",
"given": "B."
}
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "C."
}
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "J."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Clavel-M",
"name": {
"family": "Clavel",
"given": "M."
},
"orcid": "0000-0003-0724-2742"
},
{
"id": "Rahoui-F",
"name": {
"family": "Rahoui",
"given": "F."
},
"orcid": "0000-0001-7655-4120"
},
{
"id": "Lal-D-V",
"name": {
"family": "Lal",
"given": "D. V."
},
"orcid": "0000-0001-5470-305X"
},
{
"id": "Roy-S",
"name": {
"family": "Roy",
"given": "S."
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
}
]
},
"title": "NuSTAR + XMM-Newton monitoring of the neutron star transient AX J1745.6-2901",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion discs \u2013 methods: observational \u2013 techniques: spectroscopic \u2013 stars: neutron \u2013 absorption lines \u2013X-rays: binaries",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. \n\nAccepted 2017 September 18. Received 2017 September 18; in original form 2017 May 13. Published: 22 September 2017. \n\nThe authors wish to thank Jan-Uwe Ness, Karl Foster, Ignacio de la Calle and the rest of the XMM-Newton and NuSTAR scheduling teams for the support that made the coordinated observations possible. We would like to thank the referee for the helpful comments and careful reading of the paper. The GC XMM-Newton monitoring project is supported by the Bundesministerium f\u00fcr Wirtschaft und Technologie/Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (BMWI/DLR, FKZ 50 OR 1408 and FKZ 50 OR 1408) and the Max Planck Society. SB acknowledges financial support from the Italian Space Agency under grant ASI-INAF I/037/12/0. TMD acknowledges support via a Ram\u00f3n y Cajal Fellowship (RYC-2015-18148). BDM acknowledges support from the European Union's Horizon 2020 research and innovation programme and the Polish National Science Centre grant Polonez 2016/21/P/ST9/04025. These results are based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NUSTARDAS jointly developed by the ASI Science Data Centre (ASDC, Italy) and the California Institute of Technology (USA). We thank the staff of the GMRT who have made these observations possible. The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. Part of the funding for GROND (both hardware as well as personnel) was generously granted from the Leibniz-Prize to Prof. G. Hasinger (DFG grant HA 1850/28-1).\n\nPublished - stx2425.pdf
Accepted Version - 1709.06571.pdf
",
"abstract": "AX J1745.6-2901 is a high-inclination (eclipsing) transient neutron star (NS) low-mass X-ray binary showcasing intense ionized Fe K absorption. We present here the analysis of 11 XMM-Newton and 15 NuSTAR new data sets (obtained between 2013 and 2016), therefore tripling the number of observations of AX J1745.6-2901 in outburst. Thanks to simultaneous XMM-Newton and NuSTAR spectra, we greatly improve on the fitting of the X-ray continuum. During the soft state, the emission can be described by a disc blackbody (kT \u223c 1.1\u20131.2\u2009keV and inner disc radius rDBB \u223c 14 km), plus hot (kT \u223c 2.2\u20133.0\u2009keV) blackbody radiation with a small emitting radius (rBB \u223c 0.5 \u2212 0.8 km) likely associated with the boundary layer or NS surface, plus a faint Comptonization component. Imprinted on the spectra are clear absorption features created by both neutral and ionized matter. Additionally, positive residuals suggestive of an emission Fe K\u2009\u03b1 disc line and consistent with relativistic ionized reflection are present during the soft state, while such residuals are not significant during the hard state. The hard-state spectra are characterized by a hard (\u0393 \u223c 1.9\u20132.1) power law, showing no evidence for a high energy cut-off (kTe > 60\u2013140\u2009keV) and implying a small optical depth (\u03c4 < 1.6). The new observations confirm the previously witnessed trend of exhibiting strong Fe K absorption in the soft state that significantly weakens during the hard state. Optical (GROND) and radio (GMRT) observations suggest for AX J1745.6-2901 a standard broad-band spectral energy distribution as typically observed in accreting NSs.",
"date": "2018-01-11",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "473",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2304-2323",
"id_number": "CaltechAUTHORS:20170921-135527394",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170921-135527394",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Bundesministerium f\u00fcr Wirtschaft und Technologie (BMWi)"
},
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)",
"grant_number": "FKZ 50 OR 1408"
},
{
"agency": "Max Planck Society"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0"
},
{
"agency": "Ram\u00f3n y Cajal programme",
"grant_number": "RYC-2015-18148"
},
{
"agency": "European Union Horizon 2020 Research and Innovation Program"
},
{
"agency": "National Science Centre (Poland)",
"grant_number": "2016/21/P/ST9/04025"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Deutsche Forschungsgemeinschaft (DFG)",
"grant_number": "HA 1850/28-1"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1093/mnras/stx2425",
"primary_object": {
"basename": "1709.06571.pdf",
"url": "https://authors.library.caltech.edu/records/zjvy9-1ny89/files/1709.06571.pdf"
},
"related_objects": [
{
"basename": "stx2425.pdf",
"url": "https://authors.library.caltech.edu/records/zjvy9-1ny89/files/stx2425.pdf"
}
],
"pub_year": "2018",
"author_list": "Ponti, G.; Bianchi, S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9mtkt-sa928",
"eprint_id": 84345,
"eprint_status": "archive",
"datestamp": "2023-08-19 07:21:10",
"lastmod": "2026-04-01 03:13:34",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "Poshak"
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "Jon M."
}
},
{
"id": "Parker-M-L",
"name": {
"family": "Parker",
"given": "Michael L."
},
"orcid": "0000-0002-8466-7317"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "Reflection Spectra of the Black Hole Binary Candidate MAXI J1535-571 in the Hard State Observed by NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 black hole physics \u2013 X-rays: binaries",
"note": "\u00a9 2018 The American Astronomical Society. \n\nReceived 2017 November 2; revised 2018 January 2; accepted 2018 January 2; published 2018 January 12. \n\nWe thank the referee for constructive comments that improved the Letter. D.J.W. acknowledges support from STFC Ernest Rutherford Fellowship. J.A.G. acknowledges support from NASA grant No. 80NSSC17K0515 and the Alexander von Humboldt Foundation. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Xu_2018_ApJL_852_L34.pdf
Submitted - 1711.01346.pdf
",
"abstract": "We report on a Nuclear Spectroscopic Telescope Array (NuSTAR) observation of the recently discovered bright black hole candidate MAXI J1535-571. NuSTAR observed the source on MJD 58003 (five days after the outburst was reported). The spectrum is characteristic of a black hole binary in the hard state. We observe clear disk reflection features, including a broad Fe K\u03b1 line and a Compton hump peaking around 30 keV. Detailed spectral modeling reveals a narrow Fe K\u03b1 line complex centered around 6.5 keV on top of the strong relativistically broadened Fe K\u03b1 line. The narrow component is consistent with distant reflection from moderately ionized material. The spectral continuum is well described by a combination of cool thermal disk photons and a Comptonized plasma with the electron temperature kT_e = 19.7 \u00b1 0.4 keV. An adequate fit can be achieved for the disk reflection features with a self-consistent relativistic reflection model that assumes a lamp-post geometry for the coronal illuminating source. The spectral fitting measures a black hole spin a > 0.84, inner disk radius R_(in) < 2.01 r_(ISCO) , and a lamp-post height h = 7.2^(+0.8)_(-2.0) r_g (statistical errors, 90% confidence), indicating no significant disk truncation and a compact corona. Although the distance and mass of this source are not currently known, this suggests the source was likely in the brighter phases of the hard state during this NuSTAR observation.",
"date": "2018-01-10",
"date_type": "published",
"publication": "Astrophysical Journal Letters",
"volume": "852",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. L34",
"id_number": "CaltechAUTHORS:20180116-152713791",
"issn": "2041-8213",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180116-152713791",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "80NSSC17K0515"
},
{
"agency": "Alexander von Humboldt Foundation"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/2041-8213/aaa4b2",
"primary_object": {
"basename": "1711.01346.pdf",
"url": "https://authors.library.caltech.edu/records/9mtkt-sa928/files/1711.01346.pdf"
},
"related_objects": [
{
"basename": "Xu_2018_ApJL_852_L34.pdf",
"url": "https://authors.library.caltech.edu/records/9mtkt-sa928/files/Xu_2018_ApJL_852_L34.pdf"
}
],
"pub_year": "2018",
"author_list": "Xu, Yanjun; Harrison, Fiona A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0mj2j-kdd35",
"eprint_id": 84530,
"eprint_status": "archive",
"datestamp": "2023-08-19 07:09:52",
"lastmod": "2025-06-30 18:07:56",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Porquet-D",
"name": {
"family": "Porquet",
"given": "D."
},
"orcid": "0000-0001-9731-0352"
},
{
"id": "Reeves-J-N",
"name": {
"family": "Reeves",
"given": "J. N."
}
},
{
"id": "Matt-G",
"name": {
"family": "Matt",
"given": "G."
},
"orcid": "0000-0002-2152-0916"
},
{
"id": "Marinucci-A",
"name": {
"family": "Marinucci",
"given": "A."
}
},
{
"id": "Nardini-E",
"name": {
"family": "Nardini",
"given": "E."
},
"orcid": "0000-0001-9226-8992"
},
{
"id": "Braito-V",
"name": {
"family": "Braito",
"given": "V."
},
"orcid": "0000-0002-2629-4989"
},
{
"id": "Lobban-A-P",
"name": {
"family": "Lobban",
"given": "A."
},
"orcid": "0000-0002-6433-1357"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "S. E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "F. E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Dauser-T",
"name": {
"family": "Dauser",
"given": "T."
},
"orcid": "0000-0003-4583-9048"
},
{
"id": "Farrah-D",
"name": {
"family": "Farrah",
"given": "D."
},
"orcid": "0000-0003-1748-2010"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "C. J."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Tortosa-A",
"name": {
"family": "Tortosa",
"given": "A."
}
},
{
"id": "Ursini-F",
"name": {
"family": "Ursini",
"given": "F."
}
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "W. W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "A deep X-ray view of the bare AGN Ark 120. IV. XMM-Newton and NuSTAR spectra dominated by two temperature (warm, hot) Comptonization processes",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-rays: individuals: Ark 120 \u2013 galaxies: active \u2013 radiation mechanisms: general \u2013 accretion, accretion disks \u2013\nquasars: general",
"note": "\u00a9 2018 ESO. Article published by EDP Sciences.\n\nReceived 1 June 2017; Accepted 24 July 2017; Published online 05 January 2018.\n\nThe authors would like to deeply thank the anonymous referee for useful and constructive comments. The paper is based on observations obtained with the XMM-Newton, and ESA science mission with instruments and contributions directly funded by ESA member states and the USA (NASA). This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by NASA. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center and the California Institute of Technology. D.P. would like to acknowledge financial support from the French \"Programme National Hautes \u00c9nergies\" (PNHE). Part of the work was supported by the European Union Seventh Framework Program under the grant agreement No. 312789 (D.P., G.M., A.M., A.F.). J.N.R. acknowledges financial support via Chandra grant number GO4-15092X and NASA grant NNX15AF12G. J.N.R. and A.L. also acknowledge the support of the STFC, via the consolidated grant ST/M001040/1. G.M., A.M., A.T. and F.U. acknowledge financial support from the Italian Space Agency under grant ASI/INAF I/037/12/0-011/13. E.N. acknowledges funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 664931.\n\nPublished - aa31290-17.pdf
Submitted - 1707.08907.pdf
",
"abstract": "Context. The physical characteristics of the material closest to supermassive black holes (SMBHs) are primarily studied through X-ray observations. However, the origins of the main X-ray components such as the soft X-ray excess, the Fe\u2009K\u03b1 line complex, and the hard X-ray excess are still hotly debated. This is particularly problematic for active galactic nuclei (AGN) showing a significant intrinsic absorption, either warm or neutral, which can severely distort the observed continuum. Therefore, AGN with no (or very weak) intrinsic absorption along the line of sight, so-called \"bare AGN\", are the best targets to directly probe matter very close to the SMBH.\nAims. We perform an X-ray spectral analysis of the brightest and cleanest bare AGN known so far, Ark\u2009120, in order to determine the process(es) at work in the vicinity of the SMBH.\nMethods. We present spectral analyses of data from an extensive campaign observing Ark\u2009120 in X-rays with XMM-Newton (4 \u00d7 120\u2009ks, 2014 March 18\u201324), and NuSTAR (65.5\u2009ks, 2014 March 22).\nResults. During this very deep X-ray campaign, the source was caught in a high-flux state similar to the earlier 2003 XMM-Newton observation, and about twice as bright as the lower-flux observation in 2013. The spectral analysis confirms the \"softer when brighter\" behavior of Ark\u2009120. The four XMM-Newton/pn spectra are characterized by the presence of a prominent soft X-ray excess and a significant Fe\u2009K\u03b1 complex. The continuum is very similar above about 3\u2009keV, while significant variability is present for the soft X-ray excess. We find that relativistic reflection from a constant-density, flat accretion disk cannot simultaneously produce the soft excess, broad Fe\u2009K\u03b1 complex, and hard X-ray excess. Instead, Comptonization reproduces the broadband (0.3\u201379 keV) continuum well, together with a contribution from a mildly relativistic disk reflection spectrum.\nConclusions. During this 2014 observational campaign, the soft X-ray spectrum of Ark 120 below ~0.5\u2009keV was found to be dominated by Comptonization of seed photons from the disk by a warm (kTe ~ 0.5\u2009keV), optically-thick corona (\u03c4 ~ 9). Above this energy, the X-ray spectrum becomes dominated by Comptonization from electrons in a hot optically thin corona, while the broad Fe\u2009K\u03b1 line and the mild Compton hump result from reflection off the disk at several tens of gravitational radii.",
"date": "2018-01",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "609",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A42",
"id_number": "CaltechAUTHORS:20180125-144741618",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180125-144741618",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Programme National Hautes \u00c9nergies (PNHE)"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "312789"
},
{
"agency": "NASA",
"grant_number": "GO4-15092X"
},
{
"agency": "NASA",
"grant_number": "NNX15AF12G"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/M001040/1"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0-011/13"
},
{
"agency": "Marie Curie Fellowship",
"grant_number": "664931"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1051/0004-6361/201731290",
"primary_object": {
"basename": "1707.08907.pdf",
"url": "https://authors.library.caltech.edu/records/0mj2j-kdd35/files/1707.08907.pdf"
},
"related_objects": [
{
"basename": "aa31290-17.pdf",
"url": "https://authors.library.caltech.edu/records/0mj2j-kdd35/files/aa31290-17.pdf"
}
],
"pub_year": "2018",
"author_list": "Porquet, D.; Reeves, J. N.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/6vcch-hm513",
"eprint_id": 82060,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:58:58",
"lastmod": "2025-06-30 18:07:45",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Evans-P-A",
"name": {
"family": "Evans",
"given": "P. A."
},
"orcid": "0000-0002-8465-3353"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Y."
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "K."
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "B."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "H."
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Pike-S-N",
"name": {
"family": "Pike",
"given": "S."
},
"orcid": "0000-0002-8403-0041"
},
{
"id": "Rosswog-S",
"name": {
"family": "Rosswog",
"given": "S."
}
}
]
},
"title": "Swift and NuSTAR observations of GW170817: detection of a blue kilonova",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2017 American Association for the Advancement of Science. \n\nReceived 14 September 2017; accepted 4 October 2017; Published online 16 October 2017. \n\nWe acknowledge the leadership and scientific vision of Neil Gehrels (1952\u20132017), former PI of Swift, without whom the work we present here would not have been possible. Funding for the Swift mission in the UK is provided by the UK Space Agency. SRO gratefully acknowledges the support of the Leverhulme Trust Early Career Fellowship (SRO). The Swift team at the MOC at Penn State acknowledges support from NASA contract NAS5-00136. The Italian Swift team acknowledge support from ASI-INAF grant I/004/11/3. SR has been supported by the Swedish Research Council (VR) under grant number 2016-03657_3, by the Swedish National Space Board under grant number Dnr. 107/16 and by the research environment grant \"Gravitational Radiation and Electromagnetic Astrophysical Transients (GREAT)\" funded by the Swedish Research council (VR) under Dnr 2016- 06012. This research used resources provided by the Los Alamos National Laboratory Institutional Computing Program, which is supported by the U.S. Department of Energy National Nuclear Security Administration under Contract No. DE-AC52-06NA25396. VLT data were obtained under ESO program number 099.D-0668. NuSTAR acknowledges funding from NASA Contract No. NNG08FD60C. A.J.L. and N.R.T. acknowledge funding from the European Research Council under the European Union's Horizon 2020 programme, grant number 725246. Researchers at Los Alamos National Laboratory were supported by the National Nuclear Security Administration of the US Department of Energy under contract number DE-AC52-06NA25396. SWKE is supported by a Science and Technology Facilities Council studentship. The observations are archived at http://www.swift.ac.uk for Swift and https://heasarc.gsfc.nasa.gov/docs/nustar/nustar_archive.html for NuSTAR, under the observation IDs given in Table S2. Reduced photometry and surveyed areas are tabulated in the supplementary material. The BOXFIT software is available at http://cosmo.nyu.edu/afterglowlibrary/boxfit2011.html, SUPERNU at https://bitbucket.org/drrossum/supernu/wiki/Home, access to WINNET source code and input files will be granted upon request via: https://bitbucket.org/korobkin/winnet. The dynamical model ejecta are available at http://compact-merger.astro.su.se/downloads_fluid_trajectories.html (as run 12). The SUPERNU and BOXFIT input files are available in the supplementary materials.\n\nAccepted Version - 1710.05437.pdf
Supplemental Material - aap9580-Evans-SM.pdf
Supplemental Material - aap9580-Evans-SM_add_data.zip
",
"abstract": "With the first direct detection of merging black holes in 2015, the era of gravitational wave (GW) astrophysics began. A complete picture of compact object mergers, however, requires the detection of an electromagnetic (EM) counterpart. We report ultraviolet (UV) and x-ray observations by Swift and the Nuclear Spectroscopic Telescope Array of the EM counterpart of the binary neutron star merger GW170817. The bright, rapidly fading UV emission indicates a high mass (\u22480.03 solar masses) wind-driven outflow with moderate electron fraction (Ye \u2248 0.27). Combined with the x-ray limits, we favor an observer viewing angle of \u224830\u00b0 away from the orbital rotation axis, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultrarelativistic, highly collimated ejecta (a \u03b3-ray burst afterglow).",
"date": "2017-12-22",
"date_type": "published",
"publication": "Science",
"volume": "358",
"number": "6370",
"publisher": "American Association for the Advancement of Science",
"pagerange": "1565-1570",
"id_number": "CaltechAUTHORS:20171004-130639886",
"issn": "0036-8075",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171004-130639886",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "United Kingdom Space Agency (UKSA)"
},
{
"agency": "Leverhulme Trust"
},
{
"agency": "NASA",
"grant_number": "NAS5-00136"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/004/11/3"
},
{
"agency": "Swedish Research Council",
"grant_number": "2016-03657_3"
},
{
"agency": "Swedish National Space Board",
"grant_number": "Dnr. 107/16"
},
{
"agency": "Swedish Research Council",
"grant_number": "Dnr 2016-06012"
},
{
"agency": "Department of Energy (DOE)",
"grant_number": "DE-AC52-06NA25396"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "725246"
},
{
"agency": "Science and Technology Facilities Council (STFC)"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1126/science.aap9580",
"primary_object": {
"basename": "1710.05437.pdf",
"url": "https://authors.library.caltech.edu/records/6vcch-hm513/files/1710.05437.pdf"
},
"related_objects": [
{
"basename": "aap9580-Evans-SM_add_data.zip",
"url": "https://authors.library.caltech.edu/records/6vcch-hm513/files/aap9580-Evans-SM_add_data.zip"
},
{
"basename": "aap9580-Evans-SM.pdf",
"url": "https://authors.library.caltech.edu/records/6vcch-hm513/files/aap9580-Evans-SM.pdf"
}
],
"pub_year": "2017",
"author_list": "Evans, P. A.; Madsen, K. K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xz4fh-5c285",
"eprint_id": 83958,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:56:14",
"lastmod": "2026-04-01 19:36:11",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Xu-Yanjun",
"name": {
"family": "Xu",
"given": "Yanjun"
},
"orcid": "0000-0003-2443-3698"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "Dominic J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Bachetti-M",
"name": {
"family": "Bachetti",
"given": "Matteo"
},
"orcid": "0000-0002-4576-9337"
},
{
"id": "King-A-L",
"name": {
"family": "King",
"given": "Ashley L."
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "Jon M."
}
},
{
"id": "Grinberg-V",
"name": {
"family": "Grinberg",
"given": "Victoria"
},
"orcid": "0000-0003-2538-0188"
}
]
},
"title": "Spectral and Timing Properties of IGR J17091\u20133624 in the Rising Hard State During Its 2016 Outburst",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 black hole physics \u2013 X-rays: binaries \u2013 X-rays: individual (IGR J17091\u20133624)",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 August 10; revised 2017 November 2; accepted 2017 November 12; published 2017 December 18. \n\nWe thank the anonymous referee for detailed and helpful comments. D.J.W. acknowledges support from an STFC Ernest Rutherford Fellowship. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS), jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Xu_2017_ApJ_851_103.pdf
Submitted - 1711.04421.pdf
",
"abstract": "We present a spectral and timing study of the NuSTAR and Swift observations of the black hole candidate IGR J17091\u20133624 in the hard state during its outburst in 2016. Disk reflection is detected in each of the NuSTAR spectra taken in three epochs. Fitting with relativistic reflection models reveals that the accretion disk is truncated during all epochs with R_(in) > 10 r_g, with the data favoring a low disk inclination of ~30\u00b0\u201340\u00b0. The steepening of the continuum spectra between epochs is accompanied by a decrease in the high energy cutoff: the electron temperature kT_e drops from ~64 to ~26 keV, changing systematically with the source flux. We detect type-C QPOs in the power spectra with frequency varying between 0.131 and 0.327 Hz. In addition, a secondary peak is found in the power spectra centered at about 2.3 times the QPO frequency during all three epochs. The nature of this secondary frequency is uncertain; however, a non-harmonic origin is favored. We investigate the evolution of the timing and spectral properties during the rising phase of the outburst and discuss their physical implications.",
"date": "2017-12-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "851",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 103",
"id_number": "CaltechAUTHORS:20171219-092934959",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171219-092934959",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Science and Technology Facilities Council (STFC)"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa9ab4",
"primary_object": {
"basename": "1711.04421.pdf",
"url": "https://authors.library.caltech.edu/records/xz4fh-5c285/files/1711.04421.pdf"
},
"related_objects": [
{
"basename": "Xu_2017_ApJ_851_103.pdf",
"url": "https://authors.library.caltech.edu/records/xz4fh-5c285/files/Xu_2017_ApJ_851_103.pdf"
}
],
"pub_year": "2017",
"author_list": "Xu, Yanjun; Garc\u00eda, Javier A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/b403h-wn779",
"eprint_id": 83784,
"eprint_status": "archive",
"datestamp": "2023-09-22 22:39:48",
"lastmod": "2023-10-23 23:26:05",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Dallilar-Y",
"name": {
"family": "Dallilar",
"given": "Yigit"
}
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
}
]
},
"title": "A precise measurement of the magnetic field in the corona of the black hole binary V404 Cygni",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2017 American Association for the Advancement of Science. \n\nReceived 22 February 2017; accepted 3 November 20. \n\nThe near-infrared light curve is based on observations made with the Gran Telescopio Canarias, installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof\u00edsica de Canarias, in the island of La Palma, during science commissioning of CIRCE. Development of CIRCE was supported by the University of Florida and the National Science Foundation (grant AST-0352664), in collaboration with the Inter-University Centre for Astronomy and Astrophysics. The William Herschel Telescope is operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof\u00edsica de Canarias. The ULTRACAM team and P.G. (grant ST/J003697/2) acknowledge the financial support of the U.K. Science and Technology Facilities Council. This research has made use of data obtained with NuSTAR, a project led by the California Institute of Technology, funded by NASA and managed by NASA/Jet Propulsion Laboratory, and has used the NUSTARDAS software package, jointly developed by the Agenzia Spaziale Italiana Science Data Center (Italy) and California Institute of Technology (USA). A.J.C.-T. acknowledges support from the Spanish Ministry Project AYA2015-71718-R. We thank S. Markoff, C. Ceccobello, and T. Maccarone for comments on the scientific discussion. The multiwavelength lightcurves are provided as data file S1, and our derived measurements are listed in table S1. The observational data are available for each instrument: CIRCE at http://astro.ufl.edu/~ydallilar/Dallilar17/CIRCEraw; ULTRACAM at https://sotonac-my.sharepoint.com/personal/pg3e14_soton_ac_uk/Documents/Forms/All.aspx?slrid=603d299e%2D704d%2D4000%2Dbf01%2Dc1708c50f62d&RootFolder=%2Fpersonal%2Fpg3e14%5Fsoton%5Fac%5Fuk%2FDocuments%2Fv404&FolderCTID0x012000F83BE7EA86B4FE49BECFDAA6CEB2B068 (in ULTRACAM pipeline binary format); NuSTAR at https://heasarc.gsfc.nasa.gov/FTP/nustar/data/obs/01/9/90102007011; and AMI at www.tauceti.caltech.edu/kunal/uploads/SWIFT_643949-150625.fits (in radio Flexible Image Transport System format).\n\nSubmitted - science_manuscript_jun11.pdf
Supplemental Material - aan0249-Dallilar-SM.pdf
Supplemental Material - aan0249_Dallilar_SM-Data-File-S1.zip
",
"abstract": "Observations of binary stars containing an accreting black hole or neutron star often show x-ray emission extending to high energies (>10 kilo\u00ad\u2013electron volts), which is ascribed to an accretion disk corona of energetic particles akin to those seen in the solar corona. Despite their ubiquity, the physical conditions in accretion disk coronae remain poorly constrained. Using simultaneous infrared, optical, x-ray, and radio observations of the Galactic black hole system V404 Cygni, showing a rapid synchrotron cooling event in its 2015 outburst, we present a precise 461 \u00b1 12 gauss magnetic field measurement in the corona. This measurement is substantially lower than previous estimates for such systems, providing constraints on physical models of accretion physics in black hole and neutron star binary systems.",
"date": "2017-12-08",
"date_type": "published",
"publication": "Science",
"volume": "358",
"number": "6368",
"publisher": "American Association for the Advancement of Science",
"pagerange": "1299-1302",
"id_number": "CaltechAUTHORS:20171211-081010239",
"issn": "0036-8075",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171211-081010239",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "University of Florida"
},
{
"agency": "NSF",
"grant_number": "AST-0352664"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/J003697/2"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCINN)",
"grant_number": "AYA2015-71718-R"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
}
]
},
"doi": "10.1126/science.aan0249",
"primary_object": {
"basename": "aan0249_Dallilar_SM-Data-File-S1.zip",
"url": "https://authors.library.caltech.edu/records/b403h-wn779/files/aan0249_Dallilar_SM-Data-File-S1.zip"
},
"related_objects": [
{
"basename": "aan0249-Dallilar-SM.pdf",
"url": "https://authors.library.caltech.edu/records/b403h-wn779/files/aan0249-Dallilar-SM.pdf"
},
{
"basename": "science_manuscript_jun11.pdf",
"url": "https://authors.library.caltech.edu/records/b403h-wn779/files/science_manuscript_jun11.pdf"
}
],
"pub_year": "2017",
"author_list": "Dallilar, Yigit and F\u00fcrst, Felix"
},
{
"id": "https://authors.library.caltech.edu/records/5me0w-mkc17",
"eprint_id": 101100,
"eprint_status": "archive",
"datestamp": "2023-09-15 06:26:27",
"lastmod": "2026-04-01 16:26:29",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Webber-W-R",
"name": {
"family": "Webber",
"given": "W. R."
}
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "N."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "B."
}
}
]
},
"title": "Voyager 1 Measurements Beyond the Heliopause of Galactic Cosmic Ray Helium, Boron, Carbon, Oxygen, Magnesium, Silicon and Iron Nuclei with Energies 0.5 to >1.5 GeV/nuc",
"ispublished": "unpub",
"full_text_status": "public",
"note": "The authors are grateful to the Voyager team that designed and built the CRS experiment with the hope that one day it would measure the galactic spectra of nuclei and electrons. This includes the present team with Ed Stone as PI, Alan Cummings, Nand Lal and Bryant Heikkila, and to others who are no longer members of the team, F.B. McDonald and R.E. Vogt. Their prescience will not be forgotten. This work has been supported by NASA Grant NNN12AA01C.\n\nSubmitted - 1712.02818.pdf
",
"abstract": "We have obtained the energy spectra of cosmic ray He, B, C, O, Mg, S and Fe nuclei in the range 0.5-1.5 GeV/nuc and above using the penetrating particle mode of the High Energy Telescope, part of the Cosmic Ray Science (CRS) experiment on Voyagers 1 and 2. The data analysis procedures are the same as those used to obtain similar spectra from the identical V2 HET telescope while it was in the heliosphere between about 23 and 54 AU. The time period of analysis includes 4 years of data beyond the heliopause (HP). These new interstellar spectra are compared with various earlier experiments at the same energies at the Earth to determine the solar modulation parameter, \u03a6. These new spectra are also compared with recent measurements of the spectra of the same nuclei measured by the same telescope at low energies. It is found that the ratio of intensities at 100 MeV/nuc to those at 1.0 GeV/nuc are significantly Z dependent. Some of this Z dependence can be explained by the Z\u00b2 dependence of energy loss by ionization in the 7-10 g/cm\u00b2 of interstellar H and He traversed by cosmic rays of these energies in the galaxy; some by the Z dependent loss due to nuclear interactions in this same material; some by possible differences in the source spectra of these nuclei and some by the non-uniformity of the source distribution and propagation conditions. The observed features of the spectra, also including a Z dependence of the peak intensities of the various nuclei, pose interesting problems related to the propagation and source distribution of these cosmic rays.",
"date": "2017-12-07",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20200204-081707376",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200204-081707376",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1712.02818",
"primary_object": {
"basename": "1712.02818.pdf",
"url": "https://authors.library.caltech.edu/records/5me0w-mkc17/files/1712.02818.pdf"
},
"pub_year": "2017",
"author_list": "Webber, W. R.; Lal, N.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/wq4vb-p9948",
"eprint_id": 83540,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:27:35",
"lastmod": "2026-04-01 20:54:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kosec-Peter",
"name": {
"family": "Kosec",
"given": "P."
},
"orcid": "0000-0003-4511-8427"
},
{
"id": "Brightman-Murray",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "M\u00fcller-S\u00e1nchez-Francisco",
"name": {
"family": "M\u00fcller-S\u00e1nchez",
"given": "F."
},
"orcid": "0000-0002-2713-0628"
},
{
"id": "Koss-Michael-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Oh-Kyuseok",
"name": {
"family": "Oh",
"given": "K."
},
"orcid": "0000-0002-5037-951X"
},
{
"id": "Assef-Roberto-J",
"name": {
"family": "Assef",
"given": "R. J."
},
"orcid": "0000-0002-9508-3667"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Jun-Hyunsung-David",
"name": {
"family": "Jun",
"given": "H."
},
"orcid": "0000-0003-1470-5901"
},
{
"id": "Masini-Alberto",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Walton-Dominic-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "E."
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Comerford-Julia-M",
"name": {
"family": "Comerford",
"given": "J."
},
"orcid": "0000-0001-8627-4907"
},
{
"id": "Privon-George-C",
"name": {
"family": "Privon",
"given": "G."
},
"orcid": "0000-0003-3474-1125"
}
]
},
"title": "Investigating the Evolution of the Dual AGN System ESO 509-IG066",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: individual (ESO 509-IG066) \u2013 galaxies: nuclei \u2013 galaxies: Seyfert \u2013 X-rays: galaxies",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 January 9; revised 2017 September 13; accepted 2017 October 5; published 2017 November 28. \n\nWe thank the referee for their constructive input on our manuscript. We also thank Mislav Balokovi\u0107 for introducing us to these interesting galaxies and Jared Gabor for useful discussion. R.J.A. was supported by FONDECYT grant number 1151408. A.M. acknowledges support from the ASI/INAF grant I/037/12/0-011/13. C.R. acknowledges financial support from the CONICYT-Chile grants \"EMBIGGEN\" Anillo ACT1101, FONDECYT 1141218, Basal-CATA PFB\u201306/2007 and from the China-CONICYT fund. This work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). The work presented here was also based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. The data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This research has also made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. Furthermore, this research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. A.M. acknowledges support from the ASI/INAF grant I/037/12/0-011/13, and C.R. acknowledges financial support from the CONICYT-Chile grants \"EMBIGGEN\" Anillo ACT1101, FONDECYT 1141218, Basal-CATA PFB\u201306/2007, and from the China-CONICYT fund. \n\nFacilities: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, XMM-Newton (pn) - , Chandra - , Swift (XRT), WISE - , Keck (LRIS) - , Keck (OSIRIS) - .\n\nPublished - Kosec_2017_ApJ_850_168.pdf
Submitted - 1710.03233.pdf
",
"abstract": "We analyze the evolution of the dual active galactic nucleus (AGN) in ESO 509-IG066, a galaxy pair located at z = 0.034 whose nuclei are separated by 11 kpc. Previous observations with XMM-Newton on this dual AGN found evidence for two moderately obscured (N_H ~ 10\u00b2 cm\u207b\u00b2) X-ray luminous (L_X ~ 10\u2074\u00b3 erg s\u207b\u00b9) nuclear sources. We present an analysis of subsequent Chandra, NuSTAR, and Swift/XRT observations that show one source has dropped in flux by a factor of 10 between 2004 and 2011, which could be explained by either an increase in the absorbing column or an intrinsic fading of the central engine, possibly due to a decrease in mass accretion. Both of these scenarios are predicted by galaxy merger simulations. The source that has dropped in flux is not detected by NuSTAR, which argues against absorption, unless it is extreme. However, new Keck/LRIS optical spectroscopy reveals a previously unreported broad H\u03b1 line that is highly unlikely to be visible under the extreme absorption scenario. We therefore conclude that the black hole in this nucleus has undergone a dramatic drop in its accretion rate. From AO-assisted near-infrared integral-field spectroscopy of the other nucleus, we find evidence that the galaxy merger is having a direct effect on the kinematics of the gas close to the nucleus of the galaxy, providing a direct observational link between the galaxy merger and the mass accretion rate onto the black hole.",
"date": "2017-12-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "850",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 168",
"id_number": "CaltechAUTHORS:20171128-141327069",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171128-141327069",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1151408"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0-011/13"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "Anillo ACT1101"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1141218"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "Basal-CATA PFB-06/2007"
},
{
"agency": "China-CONICYT Fund"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "W. M. Keck Foundation"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa932e",
"primary_object": {
"basename": "1710.03233.pdf",
"url": "https://authors.library.caltech.edu/records/wq4vb-p9948/files/1710.03233.pdf"
},
"related_objects": [
{
"basename": "Kosec_2017_ApJ_850_168.pdf",
"url": "https://authors.library.caltech.edu/records/wq4vb-p9948/files/Kosec_2017_ApJ_850_168.pdf"
}
],
"pub_year": "2017",
"author_list": "Kosec, P.; Brightman, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9htd6-rrg90",
"eprint_id": 80902,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:13:17",
"lastmod": "2025-06-30 18:07:53",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "An elevation of 0.1 light-seconds for the optical jet base in an accreting Galactic black hole system",
"ispublished": "pub",
"full_text_status": "public",
"note": "\u00a9 2017 Macmillan Publishers Limited, part of Springer Nature. \n\nReceived: 24 February 2017; Accepted: 07 September 2017;\nPublished online: 30 October 2017.\n\nThis research has made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA), as well as the High Energy Astrophysics Science Archive Research Center. P.G. thanks the Science and Technology Facilities Council (STFC) for support (grant reference ST/J003697/2). ULTRACAM and V.S.D. are supported by STFC grant ST/M001350/1. P.G. thanks C.B. Markwardt, C.M. Boon, A.B. Hill, M. Fiocchi, K. Forster, A. Zoghbi and T. Mu\u00f1oz-Darias for help and discussions. J.C. acknowledges financial support from the Spanish Ministry of Economy, Industry and Competitiveness (MINECO) under the 2015 Severo Ochoa Program MINECO SEV-2015-0548, and to the Leverhulme Trust through grant VP2-2015-04. T.R.M. acknowledges STFC (ST/L000733/1). J.M. acknowledges financial support from the French National Research Agency (CHAOS project ANR-12-BS05-0009), and D.A. thanks the Royal Society. S.M. acknowledges support from Netherlands Organisation for Scientific Research (NWO) VICI grant no. 639.043.513. We thank P. Wallace for use of his SLA C library. P.A.C. is grateful to the Leverhulme Trust for the award of a Leverhulme Emeritus Fellowship. Part of this research was supported by the UK-India UKIERI/UGC Thematic Partnership grants UGC 2014-15/02 and IND/CONT/E/14-15/355. This work profited from discussions carried out during a meeting organized at the International Space Science Institute (ISSI) Beijing by T. Belloni and D. Bhattacharya.\n\nContributions: P.G. wrote the ULTRACAM proposal, analysed the data and wrote the paper. The ULTRACAM observations were coordinated and carried out by L.K.H., S.P.L., V.S.D. and T.R.M. The X-ray observations were proposed by D.J.W., coordinated by D.S., J.A.T. and F.A.H., and the timing data analysed by M.B. Radio data were obtained and analysed by R.P.F. and K.M. INTEGRAL data were arranged by E.K. The remaining authors provided insight into jet physics constraints (S.M., J.M., C.C.), cross-correlation analyses (P.C., R.I.H., C.K., C.F., M.P., F.V.) and placing the source in context (D.A., J.C., P.A.C., D.M.R., F.R., A.W.S.). All authors read and commented on multiple versions of the manuscript.\n\nCompeting interests: The authors declare no competing financial interests.\n\nAccepted Version - 1710.09838.pdf
Supplemental Material - 41550_2017_273_MOESM1_ESM.pdf
",
"abstract": "Relativistic plasma jets are observed in many systems that host accreting black holes. According to theory, coiled magnetic fields close to the black hole accelerate and collimate the plasma, leading to a jet being launched. Isolating emission from this acceleration and collimation zone is key to measuring its size and understanding jet formation physics. But this is challenging because emission from the jet base cannot easily be disentangled from other accreting components. Here, we show that rapid optical flux variations from an accreting Galactic black-hole binary are delayed with respect to X-rays radiated from close to the black hole by about 0.1\u2009seconds, and that this delayed signal appears together with a brightening radio jet. The origin of these subsecond optical variations has hitherto been controversial4. Not only does our work strongly support a jet origin for the optical variations but it also sets a characteristic elevation of \u227210^3 Schwarzschild radii for the main inner optical emission zone above the black hole, constraining both internal shock and magnetohydrodynamic models. Similarities with blazars suggest that jet structure and launching physics could potentially be unified under mass-invariant models. Two of the best-studied jetted black-hole binaries show very similar optical lags, so this size scale may be a defining feature of such systems.",
"date": "2017-12",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "1",
"number": "12",
"publisher": "Nature Publishing Group",
"pagerange": "859-864",
"id_number": "CaltechAUTHORS:20170829-115834040",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170829-115834040",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/J003697/2"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/M001350/1"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)"
},
{
"agency": "Centro de Excelencia Severo Ochoa",
"grant_number": "SEV-2015-0548"
},
{
"agency": "Leverhulme Trust",
"grant_number": "VP2-2015-04"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/L000733/1"
},
{
"agency": "Agence Nationale pour la Recherche (ANR)",
"grant_number": "ANR-12-BS05-0009"
},
{
"agency": "Royal Society"
},
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)",
"grant_number": "639.043.513"
},
{
"agency": "UK India Education Research Initiative (UKIERI)",
"grant_number": "UGC 2014-15/02"
},
{
"agency": "UK India Education Research Initiative (UKIERI)",
"grant_number": "IND/CONT/E/14-15/355"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1038/s41550-017-0273-3",
"primary_object": {
"basename": "1710.09838.pdf",
"url": "https://authors.library.caltech.edu/records/9htd6-rrg90/files/1710.09838.pdf"
},
"related_objects": [
{
"basename": "41550_2017_273_MOESM1_ESM.pdf",
"url": "https://authors.library.caltech.edu/records/9htd6-rrg90/files/41550_2017_273_MOESM1_ESM.pdf"
}
],
"pub_year": "2017",
"author_list": "Gandhi, P. and Harrison, F. A."
},
{
"id": "https://authors.library.caltech.edu/records/eh8c2-4ss59",
"eprint_id": 84113,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:21:58",
"lastmod": "2026-04-01 19:54:23",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ballhausen-R",
"name": {
"family": "Ballhausen",
"given": "Ralf"
}
},
{
"id": "Pottschmidt-K",
"name": {
"family": "Pottschmidt",
"given": "Katja"
},
"orcid": "0000-0002-4656-6881"
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "Felix"
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J\u00f6rn"
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Schwarm-F-W",
"name": {
"family": "Schwarm",
"given": "Fritz-Walter"
}
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Kretschmar-P",
"name": {
"family": "Kretschmar",
"given": "Peter"
},
"orcid": "0000-0001-9840-2048"
},
{
"id": "Caballero-I",
"name": {
"family": "Caballero",
"given": "Isabel"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "Steven E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "Finn E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "William W."
}
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "Charles J."
}
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "William W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "Looking at A 0535+26 at low luminosities with NuSTAR",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "X-rays: binaries / pulsars: individual: A 0535+26 / stars: neutron / accretion, accretion disks / stars: magnetic field",
"note": "\u00a9 ESO, 2017. \n\nReceived: 22 March 2017. Accepted: 10 July 2017. Published online 12 December 2017. \n\nWe thank Sebastian Falkner, Matthias K\u00fchnel, and Ingo Kreykenbohm for many fruitful discussions. We thank the Deutsches Zentrum f\u00fcr Luft- und Raumfahrt for support under contract 50\u2009OR\u20091410. This work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nThis work has made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. \n\nThis research has made use of a collection of ISIS functions (ISISscripts) provided by ECAP/Remeis observatory and MIT (http://www.sternwarte.uni-erlangen.de/isis/).\n\nPublished - aa30845-17.pdf
Submitted - 1707.05648.pdf
",
"abstract": "We report on two NuSTAR observations of the high-mass X-ray binary A 0535+26 taken toward the end of its normal 2015 outburst at very low 3\u201350\u2009keV luminosities of ~1.4 \u00d7 10^(36) erg s^(-1) and ~5 \u00d7 10^(35) erg s^(-1), which are complemented by nine Swift observations. The data clearly confirm indications seen in earlier data that the source's spectral shape softens as it becomes fainter. The smooth exponential rollover at high energies seen in the first observation evolves to a much more abrupt steepening of the spectrum at 20\u201330\u2009keV. The continuum evolution can be nicely described with emission from a magnetized accretion column, modeled using the compmag model modified by an additional Gaussian emission component for the fainter observation. Between the two observations, the optical depth changes from 0.75 \u00b1 0.04 to 0.56^(+0.01)_(-0.04), the electron temperature remains constant, and there is an indication that the column decreases in radius. Since the energy-resolved pulse profiles remain virtually unchanged in shape between the two observations, the emission properties of the accretion column reflect the same accretion regime. This conclusion is also confirmed by our result that the energy of the cyclotron resonant scattering feature (CRSF) at ~45\u2009keV is independent of the luminosity, implying that the magnetic field in the region in which the observed radiation is produced is the same in both observations. Finally, we also constrain the evolution of the continuum parameters with the rotational phase of the neutron star. The width of the CRSF could only be constrained for the brighter observation. Based on Monte Carlo simulations of CRSF formation in single accretion columns, its pulse phase dependence supports a simplified fan beam emission pattern. The evolution of the CRSF width is very similar to that of the CRSF depth, which is, however, in disagreement with expectations.",
"date": "2017-12",
"date_type": "published",
"publication": "Astronomy & Astrophysics",
"volume": "608",
"publisher": "EDP Sciences",
"pagerange": "Art. No. A105",
"id_number": "CaltechAUTHORS:20180104-163940808",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180104-163940808",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt",
"grant_number": "50\u2009OR\u20091410"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "Gaia Multilateral Agreement"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1051/0004-6361/201730845",
"primary_object": {
"basename": "1707.05648.pdf",
"url": "https://authors.library.caltech.edu/records/eh8c2-4ss59/files/1707.05648.pdf"
},
"related_objects": [
{
"basename": "aa30845-17.pdf",
"url": "https://authors.library.caltech.edu/records/eh8c2-4ss59/files/aa30845-17.pdf"
}
],
"pub_year": "2017",
"author_list": "Ballhausen, Ralf; Pottschmidt, Katja; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jw2qh-78w39",
"eprint_id": 83631,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:19:30",
"lastmod": "2026-04-01 17:12:36",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "Ed"
},
"orcid": "0000-0002-2010-5462"
}
]
},
"title": "The Voyagers",
"ispublished": "pub",
"full_text_status": "restricted",
"note": "\u00a9 2017 Macmillan Publishers Limited, part of Springer Nature. \n\nPublished online: 01 December 2017.",
"abstract": "Forty years ago, the two Voyager spacecraft left Earth to begin one of the most rewarding voyages of human discovery ever to have been undertaken. Project Scientist Ed Stone recounts his treasured moments from the mission.",
"date": "2017-12",
"date_type": "published",
"publication": "Nature Astronomy",
"volume": "1",
"number": "12",
"publisher": "Nature Publishing Group",
"pagerange": "896-896",
"id_number": "CaltechAUTHORS:20171201-145449748",
"issn": "2397-3366",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171201-145449748",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1038/s41550-017-0339-2",
"pub_year": "2017",
"author_list": "Stone, Ed"
},
{
"id": "https://authors.library.caltech.edu/records/2jk5c-3jy48",
"eprint_id": 83065,
"eprint_status": "archive",
"datestamp": "2023-08-19 06:00:37",
"lastmod": "2026-04-01 20:03:28",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Marsh-A-J",
"name": {
"family": "Marsh",
"given": "Andrew J."
},
"orcid": "0000-0003-1086-6900"
},
{
"id": "Smith-D-M",
"name": {
"family": "Smith",
"given": "David M."
},
"orcid": "0000-0002-0542-5759"
},
{
"id": "Glesener-L",
"name": {
"family": "Glesener",
"given": "Lindsay"
},
"orcid": "0000-0001-7092-2703"
},
{
"id": "Hannah-I-G",
"name": {
"family": "Hannah",
"given": "Iain G."
},
"orcid": "0000-0003-1193-8603"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Caspi-A",
"name": {
"family": "Caspi",
"given": "Amir"
},
"orcid": "0000-0001-8702-8273"
},
{
"id": "Krucker-S",
"name": {
"family": "Krucker",
"given": "S\u00e4m"
}
},
{
"id": "Hudson-H-S",
"name": {
"family": "Hudson",
"given": "Hugh S."
},
"orcid": "0000-0001-5685-1283"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "White-S-M",
"name": {
"family": "White",
"given": "Stephen M."
},
"orcid": "0000-0002-8574-8629"
},
{
"id": "Kuhar-M",
"name": {
"family": "Kuhar",
"given": "Matej"
},
"orcid": "0000-0002-7210-180X"
},
{
"id": "Wright-P-J",
"name": {
"family": "Wright",
"given": "Paul J."
},
"orcid": "0000-0001-9021-611X"
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "Steven E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "Finn E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "William W."
}
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "Charles J."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "William W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "First NuSTAR Limits on Quiet Sun Hard X-Ray Transient Events",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Sun: flares \u2013 Sun: X-rays, gamma rays",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 May 13; revised 2017 October 2; accepted 2017 October 2; published 2017 November 8. \n\nThis paper made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NUSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). Some of the figures within this paper were produced using IDL color-blind-friendly color tables (Wright 2017). The authors would like to thank Albert Shih for helpful comments and suggestions. A.M. was supported by NASA Earth and Space Science Fellowship award NNX13AM41H. I.G.H. acknowledges support from a Royal Society University Research Fellowship. S.K. acknowledges support from the Swiss National Science Foundation (200021-140308). A.C. was supported by NASA grants NNX15AK26G and NNX14AH54G. L.G. was supported by an NSF Faculty Development Grant to UMN (AGS-1429512). P.J.W. was supported by an EPSRC/Royal Society Fellowship Engagement Award (EP/M00371X/1). This work was supported by NASA grants NNX12AJ36G and NNX14AG07G. \n\nFacility: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission.\n\nPublished - Marsh_2017_ApJ_849_131.pdf
Accepted Version - 1711.05385.pdf
",
"abstract": "We present the first results of a search for transient hard X-ray (HXR) emission in the quiet solar corona with the Nuclear Spectroscopic Telescope Array (NuSTAR) satellite. While NuSTAR was designed as an astrophysics mission, it can observe the Sun above 2 keV with unprecedented sensitivity due to its pioneering use of focusing optics. NuSTAR first observed quiet-Sun regions on 2014 November 1, although out-of-view active regions contributed a notable amount of background in the form of single-bounce (unfocused) X-rays. We conducted a search for quiet-Sun transient brightenings on timescales of 100 s and set upper limits on emission in two energy bands. We set 2.5\u20134 keV limits on brightenings with timescales of 100 s, expressed as the temperature T and emission measure EM of a thermal plasma. We also set 10\u201320 keV limits on brightenings with timescales of 30, 60, and 100 s, expressed as model-independent photon fluxes. The limits in both bands are well below previous HXR microflare detections, though not low enough to detect events of equivalent T and EM as quiet-Sun brightenings seen in soft X-ray observations. We expect future observations during solar minimum to increase the NuSTAR sensitivity by over two orders of magnitude due to higher instrument livetime and reduced solar background.",
"date": "2017-11-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "849",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 131",
"id_number": "CaltechAUTHORS:20171108-103806025",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171108-103806025",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX13AM41H"
},
{
"agency": "Royal Society"
},
{
"agency": "Swiss National Science Foundation (SNSF)",
"grant_number": "200021-140308"
},
{
"agency": "NASA",
"grant_number": "NNX15AK26G"
},
{
"agency": "NASA",
"grant_number": "NNX14AH54G"
},
{
"agency": "NSF",
"grant_number": "AGS-1429512"
},
{
"agency": "Engineering and Physical Sciences Research Council (EPSRC)",
"grant_number": "EP/M00371X/1"
},
{
"agency": "NASA",
"grant_number": "NNX12AJ36G"
},
{
"agency": "NASA",
"grant_number": "NNX14AG07G"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa9122",
"primary_object": {
"basename": "Marsh_2017_ApJ_849_131.pdf",
"url": "https://authors.library.caltech.edu/records/2jk5c-3jy48/files/Marsh_2017_ApJ_849_131.pdf"
},
"related_objects": [
{
"basename": "1711.05385.pdf",
"url": "https://authors.library.caltech.edu/records/2jk5c-3jy48/files/1711.05385.pdf"
}
],
"pub_year": "2017",
"author_list": "Marsh, Andrew J.; Smith, David M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/06jk0-sgg38",
"eprint_id": 82802,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:54:47",
"lastmod": "2026-04-01 20:17:52",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Del-Moro-Agnese",
"name": {
"family": "Del Moro",
"given": "A."
}
},
{
"id": "Alexander-David-M",
"name": {
"family": "Alexander",
"given": "D. M."
},
"orcid": "0000-0002-5896-6313"
},
{
"id": "Aird-James-A",
"name": {
"family": "Aird",
"given": "J. A."
},
"orcid": "0000-0003-1908-8463"
},
{
"id": "Bauer-Franz-E",
"name": {
"family": "Bauer",
"given": "F. E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Civano-Francesca",
"name": {
"family": "Civano",
"given": "F."
},
"orcid": "0000-0002-2115-1137"
},
{
"id": "Mullaney-James-R",
"name": {
"family": "Mullaney",
"given": "J. R."
},
"orcid": "0000-0002-3126-6712"
},
{
"id": "Ballantyne-David-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Brandt-W-Niel",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "Comastri-Andrea",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Lansbury-George-B",
"name": {
"family": "Lansbury",
"given": "G. B."
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Lanz-Lauranne",
"name": {
"family": "Lanz",
"given": "L."
},
"orcid": "0000-0002-3249-8224"
},
{
"id": "Luo-Bin",
"name": {
"family": "Luo",
"given": "B."
},
"orcid": "0000-0002-9036-0063"
},
{
"id": "Marchesi-Stefano",
"name": {
"family": "Marchesi",
"given": "S."
},
"orcid": "0000-0001-5544-0749"
},
{
"id": "Puccetti-Simonetta",
"name": {
"family": "Puccetti",
"given": "S."
},
"orcid": "0000-0002-2734-7835"
},
{
"id": "Ricci-Claudio",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Saez-Cristian",
"name": {
"family": "Saez",
"given": "C."
},
"orcid": "0000-0002-4933-7208"
},
{
"id": "Stern-Daniel",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Treister-Ezequiel",
"name": {
"family": "Treister",
"given": "E."
},
"orcid": "0000-0001-7568-6412"
},
{
"id": "Zappacosta-Luca",
"name": {
"family": "Zappacosta",
"given": "L."
},
"orcid": "0000-0002-4205-6884"
}
]
},
"title": "The NuSTAR Extragalactic Survey: Average Broadband X-Ray Spectral Properties of the NuSTAR-detected AGNs",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 quasars: general \u2013 surveys \u2013 X-rays: galaxies",
"note": "\u00a9 2017 The American Astronomical Society.\n\nReceived 2017 February 6; revised 2017 September 26; accepted 2017 October 2; published 2017 October 31.\n\nWe thank A. Corral for useful discussions about the spectral averaging method presented in her work. A.D.M. thanks the financial support from the Max Plank Society and the UK Science and Technology Facilities Council (STFC, ST/L00075X/1, A.D.M. and D.M.A.; ST/K501979/1, G.B.L.). F.E.B. and E.T. acknowledge support from CONICYT-Chile (Basal-CATA PFB-06/2007, \"EMBIGGEN\" Anillo ACT1101, FONDECYT Regular 1141218 [F.E.B.] and 1160999 [E.T.]); F.E.B. also thanks the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to the Millennium Institute of Astrophysics (MAS). P.G. thanks the STFC for support (ST/J003697/2). W.N.B. acknowledges support from the Caltech NuSTAR subcontract 44A-1092750 and NASA ADP grant NNX10AC99G. A.C. and L.Z. acknowledge support from the ASI/INAF grant I/037/12/0 011/13.\n\nThis work was supported under NASA contract no. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Del_Moro_2017_ApJ_849_57.pdf
Submitted - 1710.01041.pdf
",
"abstract": "We present a study of the average X-ray spectral properties of the sources detected by the NuSTARextragalactic survey, comprising observations of the Extended Chandra Deep Field South (E-CDFS), Extended Groth Strip (EGS), and the Cosmic Evolution Survey (COSMOS). The sample includes 182 NuSTAR sources (64 detected at 8\u201324 keV), with 3\u201324 keV fluxes ranging between f_(3-24 kev) \u2248 10^(-14) and 6 \u00d7 10^(\u221213) erg cm^(\u22122) s^(\u22121) (f_(8-24 kev) \u2248 3 x 10^(-14)-3 x 10^(-13) erg cm^(\u22122) s^(\u22121)) and redshifts in the range of z = 0.04-3.21. We produce composite spectra from the Chandra + NuSTAR data (E \u2248 2-40 keV, rest frame) for all the sources with redshift identifications (95%) and investigate the intrinsic, average spectra of the sources, divided into broad-line (BL) and narrow-line (NL) active galactic nuclei (AGNs), and also in different bins of X-ray column density and luminosity. The average power-law photon index for the whole sample is \u0393 = 1.65^(+0.03)_(-0.03), flatter than the \u0393 \u2248 1.8 typically found for AGNs. While the spectral slope of BL and X-ray unabsorbed AGNs is consistent with the typical values (\u0393 = 1.79^(+0.01)_(-0.01)), a significant flattening is seen in NL AGNs and heavily absorbed sources (\u0393 = 1.60^(+0.08)_(-0.05) and \u0393 = 1.38^(+0.12)_(-0.12), respectively), likely due to the effect of absorption and to the contribution from the Compton reflection component to the high-energy flux ( E > 10 keV). We find that the typical reflection fraction in our spectra is R \u2248 0.5 (for \u0393 = 1.8), with a tentative indication of an increase of the reflection strength with X-ray column density. While there is no significant evidence for a dependence of the photon index on X-ray luminosity in our sample, we find that R decreases with luminosity, with relatively high levels of reflection (R \u2248 1.2) for L_(10-40 kev) < 10^(44) erg s^(\u22121) and R \u2248 0.3 for L_(10-40 kev) > 10^(44) erg s^(\u22121) AGNs, assuming a fixed spectral slope of \u0393 = 1.8.",
"date": "2017-11-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "849",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 57",
"id_number": "CaltechAUTHORS:20171031-103333243",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171031-103333243",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Max Plank Society"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/L00075X/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/K501979/1"
},
{
"agency": "Basal-CATA",
"grant_number": "PFB-06/2007"
},
{
"agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)",
"grant_number": "Anillo ACT1101"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1141218"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1160999"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/J003697/2"
},
{
"agency": "Caltech NuSTAR subcontract",
"grant_number": "44A-1092750"
},
{
"agency": "NASA",
"grant_number": "NNX10AC99G"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0 011/13"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa9115",
"primary_object": {
"basename": "Del_Moro_2017_ApJ_849_57.pdf",
"url": "https://authors.library.caltech.edu/records/06jk0-sgg38/files/Del_Moro_2017_ApJ_849_57.pdf"
},
"related_objects": [
{
"basename": "1710.01041.pdf",
"url": "https://authors.library.caltech.edu/records/06jk0-sgg38/files/1710.01041.pdf"
}
],
"pub_year": "2017",
"author_list": "Del Moro, A.; Alexander, D. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/by17a-k3a44",
"eprint_id": 86449,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:52:23",
"lastmod": "2026-04-01 19:47:48",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Carrasco-Casado-A",
"name": {
"family": "Carrasco-Casado",
"given": "Alberto"
},
"orcid": "0000-0002-3412-7945"
},
{
"id": "Biswas-A",
"name": {
"family": "Biswas",
"given": "Abhijit"
}
},
{
"id": "Fields-R",
"name": {
"family": "Fields",
"given": "Renny"
}
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian"
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Sburlan-S",
"name": {
"family": "Sburlan",
"given": "Suzana"
}
},
{
"id": "Toyoshima-Morio",
"name": {
"family": "Toyoshima",
"given": "Morio"
}
}
]
},
"title": "Optical communication on CubeSats \u2014 Enabling the next era in space science",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "lasercom, smallsat, cubesat, LEO, crosslink, intersatellite, deep space, KISS",
"note": "\u00a9 2017 IEEE. \n\nThis work was supported in part by the W. M. Keck Institute for Space Studies [33]. The authors also want to thank all the participants of the two workshops: Krisjani Angkasa (JPL), Alessandra Babuscia (JPL), Derek Barnes (MIT), Kerri Cahoy (MIT), Amir Caspi (SwRI), Emily Clements (MIT), Sam Dolinar (JPL), Peter Goorjian (NASA), Varoujan Gorjian (JPL), Brian Gunter (Georgia Institute of Technology), Frank Heine (Tesat Spacecom), Travis Imken (JPL), Farzana Khatri (MIT), Maxim Khatsenko (MIT), Ryan Kingsbury (Planet Labs), Jonathan Klamkin (UC Santa Barbara), David Klumpar (Montana State University), Michael Krainak (NASA), Michael K\u00fceppers (ESA), Joe Kusters (JPL), Myron Lee (MIT), Rachel Morgan (MIT), Dhack Muthulingam (JPL), Michael Peng (JPL), Sean Pike (Caltech), Joseph Riedel (JPL), Kathleen Riesing (MIT), Bryan Robinson (MIT), Darren Rowen (The Aerospace Corp.), Joel Shields (JPL), Harlan Spence (University of New Hampshire), Mark Storm (Fibertek Inc.), Jan Stupl (SGT/NASA), Jose Velazco (JPL) and Hua Xie (JPL).\n\nSubmitted - 1811.03413.pdf
",
"abstract": "CubeSats are excellent platforms to rapidly perform simple space experiments. Several hundreds of CubeSats have already been successfully launched in the past few years and the number of announced launches grows every year. These platforms provide an easy access to space for universities and organizations which otherwise could not afford it. However, these spacecraft still rely on RF communications, where the spectrum is already crowded and cannot support the growing demand for data transmission to the ground. Lasercom holds the promise to be the solution to this problem, with a potential improvement of several orders of magnitude in the transmission capacity, while keeping a low size, weight and power. Between 2016 and 2017, The Keck Institute for Space Studies (KISS), a joint institute of the California Institute of Technology and the Jet Propulsion Laboratory, brought together a group of space scientists and lasercom engineers to address the current challenges that this technology faces, in order to enable it to compete with RF and eventually replace it when high-data rate is needed. After two one-week workshops, the working group started developing a report addressing three study cases: low Earth orbit, crosslinks and deep space. This paper presents the main points and conclusions of these KISS workshops.",
"date": "2017-11",
"date_type": "published",
"publisher": "IEEE",
"place_of_pub": "Piscataway, NJ",
"pagerange": "46-52",
"id_number": "CaltechAUTHORS:20180518-103130720",
"isbn": "978-1-5090-6511-0",
"book_title": "2017 IEEE International Conference on Space Optical Systems and Applications (ICSOS)",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180518-103130720",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Keck Institute for Space Studies (KISS)"
}
]
},
"local_group": {
"items": [
{
"id": "Keck-Institute-for-Space-Studies"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1109/ICSOS.2017.8357210",
"primary_object": {
"basename": "1811.03413.pdf",
"url": "https://authors.library.caltech.edu/records/by17a-k3a44/files/1811.03413.pdf"
},
"pub_year": "2017",
"author_list": "Carrasco-Casado, Alberto; Biswas, Abhijit; et al."
},
{
"id": "https://authors.library.caltech.edu/records/9c6ha-z0275",
"eprint_id": 82158,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:41:24",
"lastmod": "2026-04-01 19:42:25",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mori-Kaya",
"name": {
"family": "Mori",
"given": "Kaya"
},
"orcid": "0000-0002-9709-5389"
},
{
"id": "Gotthelf-E-V",
"name": {
"family": "Gotthelf",
"given": "E. V."
},
"orcid": "0000-0003-3847-3957"
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "Charles J."
}
},
{
"id": "Hord-B-J",
"name": {
"family": "Hord",
"given": "Ben J."
}
},
{
"id": "de-O\u00f1a-Wilhelmi-E",
"name": {
"family": "de O\u00f1a Wilhelmi",
"given": "Emma"
}
},
{
"id": "Rahoui-F",
"name": {
"family": "Rahoui",
"given": "Farid"
},
"orcid": "0000-0001-7655-4120"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Zhang-Shuo",
"name": {
"family": "Zhang",
"given": "Shuo"
},
"orcid": "0000-0002-2967-790X"
},
{
"id": "Hong-Jaesub",
"name": {
"family": "Hong",
"given": "Jaesub"
}
},
{
"id": "Garvin-A-M",
"name": {
"family": "Garvin",
"given": "Amani M."
}
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "Steven E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "Finn E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "William W."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "William W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "NuSTAR Hard X-ray Observation of the Gamma-ray Binary Candidate HESS J1832-093",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "gamma rays: general \u2013 radiation mechanisms: non-thermal \u2013 X-rays: binaries",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 June 16; revised 2017 August 19; accepted 2017 September 12; published 2017 October 13. \n\nThis work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Mori_2017_ApJ_848_80.pdf
Submitted - 1710.02118.pdf
",
"abstract": "We present a hard X-ray observation of the TeV gamma-ray binary candidate HESS J1832\u2212093, which is coincident with the supernova remnant G22.7\u22120.2, using the Nuclear Spectroscopic Telescope Array. Non-thermal X-ray emission from XMMU J183245\u22120921539, the X-ray source associated with HESS J1832\u2212093, is detected up to ~30 keV and is well-described by an absorbed power-law model with a best-fit photon index \u0393 = 1.5 \u00b1 0.1. A re-analysis of archival Chandra and XMM-Newtondata finds that the long-term X-ray flux increase of XMMU J183245\u22120921539 is 50^(+40)_(-20)% (90% C.L.), much less than previously reported. A search for a pulsar spin period or binary orbit modulation yields no significant signal to a pulse fraction limit of f_p < 19% in the range 4 ms < P < 40 ks. No red noise is detected in the FFT power spectrum to suggest active accretion from a binary system. While further evidence is required, we argue that the X-ray and gamma-ray properties of XMMU J183245\u22120921539 are most consistent with a non-accreting binary generating synchrotron X-rays from particle acceleration in the shock formed as a result of the pulsar and stellar wind collision. We also report on three nearby hard X-ray sources, one of which may be associated with diffuse emission from a fast-moving supernova fragment interacting with a dense molecular cloud.",
"date": "2017-10-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "848",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 80",
"id_number": "CaltechAUTHORS:20171006-100701228",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171006-100701228",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa8d15",
"primary_object": {
"basename": "1710.02118.pdf",
"url": "https://authors.library.caltech.edu/records/9c6ha-z0275/files/1710.02118.pdf"
},
"related_objects": [
{
"basename": "Mori_2017_ApJ_848_80.pdf",
"url": "https://authors.library.caltech.edu/records/9c6ha-z0275/files/Mori_2017_ApJ_848_80.pdf"
}
],
"pub_year": "2017",
"author_list": "Mori, Kaya; Gotthelf, E. V.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gr8pj-5dv33",
"eprint_id": 81237,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:29:19",
"lastmod": "2026-04-01 07:06:38",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ludlam-R-M",
"name": {
"family": "Ludlam",
"given": "R. M."
},
"orcid": "0000-0002-8961-939X"
},
{
"id": "Miller-J-M",
"name": {
"family": "Miller",
"given": "J. M."
}
},
{
"id": "Degenaar-N",
"name": {
"family": "Degenaar",
"given": "N."
}
},
{
"id": "Sanna-A",
"name": {
"family": "Sanna",
"given": "A."
}
},
{
"id": "Cackett-E-M",
"name": {
"family": "Cackett",
"given": "E. M."
},
"orcid": "0000-0002-8294-9281"
},
{
"id": "Altamirano-D",
"name": {
"family": "Altamirano",
"given": "D."
},
"orcid": "0000-0002-3422-0074"
},
{
"id": "King-A-L",
"name": {
"family": "King",
"given": "A. L."
}
}
]
},
"title": "Truncation of the Accretion Disk at One Third of the Eddington Limit in the Neutron Star Low-Mass X-ray Binary Aquila X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 stars: individual (Aql X-1) \u2013 stars: neutron \u2013 X-rays: binaries",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 July 12; revised 2017 August 30; accepted 2017 September 5; published 2017 October 3. \n\nWe thank the referee for their prompt and thoughtful comments that have improved the quality of this work. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (Caltech, USA). N.D. is supported by a Vidi grant from the Netherlands Organization for Scientific Research (NWO). E.M.C. gratefully acknowledges support from the National Science Foundation through CAREER award number AST-1351222. D.A. acknowledges support from the Royal Society.\n\nPublished - Ludlam_2017_ApJ_847_135.pdf
Accepted Version - 1709.01559v1.pdf
",
"abstract": "We perform a reflection study on a new observation of the neutron star (NS) low-mass X-ray binary Aquila X-1 taken with NuSTAR during the 2016 August outburst and compare with the 2014 July outburst. The source was captured at ~32% L_(Edd), which is over four times more luminous than the previous observation during the 2014 outburst. Both observations exhibit a broadened Fe line profile. Through reflection modeling, we determine that the inner disk is truncated R_(in,2016) = 11^(+2)_(-1) R_g (where R_g= GM/c^2) and R_(in,2014) = 14 \u00b1 2 R_g (errors quoted at the 90% confidence level). Fiducial NS parameters (M_(NS) = 1.4 M\u2299, R_(NS) = 10 km) give a stellar radius of R_(NS) = 4.85 R g ; our measurements rule out a disk extending to that radius at more than the 6\u03c3 level of confidence. We are able to place an upper limit on the magnetic field strength of B \u2264 3.0\u20134.5 \u00d7 109 G at the magnetic poles, assuming that the disk is truncated at the magnetospheric radius in each case. This is consistent with previous estimates of the magnetic field strength for Aquila X-1. However, if the magnetosphere is not responsible for truncating the disk prior to the NS surface, we estimate a boundary layer with a maximum extent of R_(BL,2016) ~ 10 R_g and R_(BL,2014) ~ 6 R_g. Additionally, we compare the magnetic field strength inferred from the Fe line profile of Aquila X-1 and other NS low-mass X-ray binaries to known accreting millisecond X-ray pulsars.",
"date": "2017-10-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "847",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 135",
"id_number": "CaltechAUTHORS:20170907-090819705",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170907-090819705",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)"
},
{
"agency": "NSF",
"grant_number": "AST-1351222"
},
{
"agency": "Royal Society"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aa8b1b",
"primary_object": {
"basename": "1709.01559v1.pdf",
"url": "https://authors.library.caltech.edu/records/gr8pj-5dv33/files/1709.01559v1.pdf"
},
"related_objects": [
{
"basename": "Ludlam_2017_ApJ_847_135.pdf",
"url": "https://authors.library.caltech.edu/records/gr8pj-5dv33/files/Ludlam_2017_ApJ_847_135.pdf"
}
],
"pub_year": "2017",
"author_list": "Ludlam, R. M.; Miller, J. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ewxf4-48857",
"eprint_id": 78203,
"eprint_status": "archive",
"datestamp": "2023-08-21 21:49:17",
"lastmod": "2026-04-01 19:47:39",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Pogorelov-N-V",
"name": {
"family": "Pogorelov",
"given": "N. V."
}
},
{
"id": "Fichtner-H",
"name": {
"family": "Fichtner",
"given": "H."
}
},
{
"id": "Czechowski-A",
"name": {
"family": "Czechowski",
"given": "A."
}
},
{
"id": "Lazarian-A",
"name": {
"family": "Lazarian",
"given": "A."
}
},
{
"id": "Lembege-B",
"name": {
"family": "Lembege",
"given": "B."
}
},
{
"id": "Le-Roux-J-A",
"name": {
"family": "Le Roux",
"given": "J. A."
}
},
{
"id": "Potgieter-M-S",
"name": {
"family": "Potgieter",
"given": "M. S."
}
},
{
"id": "Scherer-K",
"name": {
"family": "Scherer",
"given": "K."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Strauss-R-D",
"name": {
"family": "Strauss",
"given": "R. D."
}
},
{
"id": "Wiengarten-T",
"name": {
"family": "Wiengarten",
"given": "T."
}
},
{
"id": "Wurz-P",
"name": {
"family": "Wurz",
"given": "P."
}
},
{
"id": "Zank-G-P",
"name": {
"family": "Zank",
"given": "G. P."
},
"orcid": "0000-0002-4642-6192"
},
{
"id": "Zhang-M",
"name": {
"family": "Zhang",
"given": "M."
}
}
]
},
"title": "Heliosheath Processes and the Structure of the Heliopause: Modeling Energetic Particles, Cosmic Rays, and Magnetic Fields",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Heliopause and solar wind termination; Heliosphere and interstellar medium interaction; Cosmic rays; Particle acceleration and transport",
"note": "\u00a9 Springer Science+Business Media Dordrecht 2017. \n\nReceived: 18 July 2016; Accepted: 21 March 2017; Published online: 6 April 2017. \n\nWe are grateful to the International Space Science Institute (ISSI) in Bern, Switzerland, that supported two meetings for an international team on the topic 'Heliosheath Processes and Structure of the Heliopause: Modeling Energetic Particles, Cosmic Rays, and Magnetic Fields' supported by the International Space Science Institute (ISSI) in Bern, Switzerland. The work of the USA team was supported, in part, by NASA grants NNX14AJ53G, NNX14AF41G, NNX14AF43G, NNX15AN72G, and NNX16AG83G, and DOE Grant DE-SC0008334. It was also partially supported by the IBEX mission as a part of NASA's Explorer program. We acknowledge NSF PRAC award ACI-1144120 and related computer resources from the Blue Waters sustained-petascale computing project. Supercomputer time allocations were also provided on SGI Pleiades by NASA High-End Computing Program award SMD-15-5860 and on Stampede by NSF XSEDE project MCA07S033. The work of HF, MSP, KS and RDS was partly carried out within the framework of the bilateral BMBF-NRF-project \"Astrohel\" (01DG15009) funded by the Bundesministerium f\u00fcr Bildung und Forschung. The responsibility of the contents of this work is with the authors.\n\nAccepted Version - 1612.02339.pdf
",
"abstract": "This paper summarizes the results obtained by the team \"Heliosheath Processes and the Structure of the Heliopause: Modeling Energetic Particles, Cosmic Rays, and Magnetic Fields\" supported by the International Space Science Institute (ISSI) in Bern, Switzerland. We focus on the physical processes occurring in the outer heliosphere, especially at its boundary called the heliopause, and in the local interstellar medium. The importance of magnetic field, charge exchange between neutral atoms and ions, and solar cycle on the heliopause topology and observed heliocentric distances to different heliospheric discontinuities are discussed. It is shown that time-dependent, data-driven boundary conditions are necessary to describe the heliospheric asymmetries detected by the Voyager spacecraft. We also discuss the structure of the heliopause, especially due to its instability and magnetic reconnection. It is demonstrated that the Rayleigh\u2013Taylor instability of the nose of the heliopause creates consecutive layers of the interstellar and heliospheric plasma which are magnetically connected to different sources. This may be a possible explanation of abrupt changes in the galactic and anomalous cosmic ray fluxes observed by Voyager 1 when it was crossing the heliopause structure for a period of about one month in the summer of 2012. This paper also discusses the plausibility of fitting simulation results to a number of observational data sets obtained by in situ and remote measurements. The distribution of magnetic field in the vicinity of the heliopause is discussed in the context of Voyager measurements. It is argued that a classical heliospheric current sheet formed due to the Sun's rotation is not observed by in situ measurements and should not be expected to exist in numerical simulations extending to the boundary of the heliosphere. Furthermore, we discuss the transport of energetic particles in the inner and outer heliosheath, concentrating on the anisotropic spatial diffusion diffusion tensor and the pitch-angle dependence of perpendicular diffusion and demonstrate that the latter can explain the observed pitch-angle anisotropies of both the anomalous and galactic cosmic rays in the outer heliosheath.",
"date": "2017-10",
"date_type": "published",
"publication": "Space Science Reviews",
"volume": "212",
"number": "1-2",
"publisher": "Springer",
"pagerange": "193-248",
"id_number": "CaltechAUTHORS:20170614-104152882",
"issn": "0038-6308",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170614-104152882",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "International Space Science Institute (ISSI)"
},
{
"agency": "NASA",
"grant_number": "NNX14AJ53G"
},
{
"agency": "NASA",
"grant_number": "NNX14AF41G"
},
{
"agency": "NASA",
"grant_number": "NNX14AF43G"
},
{
"agency": "NASA",
"grant_number": "NNX15AN72G"
},
{
"agency": "NASA",
"grant_number": "NNX16AG83G"
},
{
"agency": "DOE",
"grant_number": "DE-SC0008334"
},
{
"agency": "NSF",
"grant_number": "ACI-1144120"
},
{
"agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)",
"grant_number": "01DG15009"
}
]
},
"other_numbering_system": {
"items": [
{
"id": "2017-01",
"name": "Space Radiation Laboratory"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1007/s11214-017-0354-8",
"primary_object": {
"basename": "1612.02339.pdf",
"url": "https://authors.library.caltech.edu/records/ewxf4-48857/files/1612.02339.pdf"
},
"pub_year": "2017",
"author_list": "Pogorelov, N. V.; Fichtner, H.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/fr6s5-xny96",
"eprint_id": 82405,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:21:26",
"lastmod": "2026-04-01 17:35:39",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Staubert-R",
"name": {
"family": "Staubert",
"given": "R."
}
},
{
"id": "Klochkov-D",
"name": {
"family": "Klochkov",
"given": "D."
}
},
{
"id": "F\u00fcrst-F",
"name": {
"family": "F\u00fcrst",
"given": "F."
},
"orcid": "0000-0003-0388-0560"
},
{
"id": "Wilms-J",
"name": {
"family": "Wilms",
"given": "J."
},
"orcid": "0000-0003-2065-5410"
},
{
"id": "Rothschild-R-E",
"name": {
"family": "Rothschild",
"given": "R. E."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Inversion of the decay of the cyclotron line energy in Hercules X-1",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "magnetic fields \u2013 binaries: eclipsing \u2013 stars: neutron \u2013 radiation mechanisms: non-thermal \u2013 line: formation \u2013 X-rays: general",
"note": "\u00a9 2017 ESO. Article published by EDP Sciences. \n\nReceived 11 September 2017; Accepted 7 October 2017; Published online 27 October 2017. \n\nThe motivation for this paper are new observational data taken by the NASA satellite NuSTAR and the ESA satellite INTEGRAL. We would like to acknowledge the dedication of all the people who have contributed to the great success of these missions, especially the \"schedulers\" for their efforts with respect to the nonstandard scheduling of the observations of Her X-1. Earlier important data were provided by the equally successful NASA missions RXTE and Swift. We thank the anonymous referee for useful suggestions.\n\nPublished - aa31927-17.pdf
Accepted Version - 1710.05150.pdf
",
"abstract": "Recent observations of Her X-1 with NuSTAR and INTEGRAL in 2016 have provided\nevidence that the 20-year decay of the cyclotron line energy found between 1996\nand 2015 has ended and that an inversion with a new increase, possibly similar\nto the one observed around 1990-1993, has started. We consider this a strong\nmotivation for further observations and for enhanced efforts to significantly\nimprove our theoretical understanding of the accretion process in binary X-ray\npulsars. We speculate about the physics behind the long-term decay and its\ninversion, a possible cyclic behavior, and correlations with other variable\nobservables.",
"date": "2017-10",
"date_type": "published",
"publication": "Astronomy and Astrophysics",
"volume": "606",
"publisher": "EDP Sciences",
"pagerange": "Art. No. L13",
"id_number": "CaltechAUTHORS:20171017-090658993",
"issn": "0004-6361",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171017-090658993",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1051/0004-6361/201731927",
"primary_object": {
"basename": "aa31927-17.pdf",
"url": "https://authors.library.caltech.edu/records/fr6s5-xny96/files/aa31927-17.pdf"
},
"related_objects": [
{
"basename": "1710.05150.pdf",
"url": "https://authors.library.caltech.edu/records/fr6s5-xny96/files/1710.05150.pdf"
}
],
"pub_year": "2017",
"author_list": "Staubert, R.; Klochkov, D.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/4n7y1-j6b02",
"eprint_id": 84115,
"eprint_status": "archive",
"datestamp": "2023-08-21 21:54:26",
"lastmod": "2026-04-01 17:17:58",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "Finn E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "William W."
}
},
{
"id": "Forster-K",
"name": {
"family": "Forster",
"given": "Karl W."
},
"orcid": "0000-0001-5800-5531"
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Rana-V-R",
"name": {
"family": "Rana",
"given": "Vikram"
},
"orcid": "0000-0003-1703-8796"
}
]
},
"title": "Observational artifacts of Nuclear Spectroscopic Telescope Array: ghost rays and stray light",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "Nuclear Spectroscopic Telescope Array; optics; satellite",
"note": "\u00a9 2017 The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. \n\nPaper 17029P received Jun. 27, 2017; accepted for publication Oct. 3, 2017; published online Oct. 27, 2017. \n\nThis work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology.\n\nPublished - 044003.pdf
Accepted Version - 1711.02719.pdf
",
"abstract": "The Nuclear Spectroscopic Telescope Array (NuSTAR) launched in June 2012, flies two conical approximation Wolter-I mirrors at the end of a 10.15-m mast. The optics are coated with multilayers of Pt/C and W/Si that operate from 3 to 80 keV. Since the optical path is not shrouded, aperture stops are used to limit the field of view (FoV) from background and sources outside the FoV. However, there is still a sliver of sky (\u223c1.0\u2009\u2009deg to 4.0 deg) where photons may bypass the optics altogether and fall directly on the detector array. We term these photons stray light. Additionally, there are also photons that do not undergo the focused double reflections in the optics, and we term these ghost rays. We present detailed analysis and characterization of these two components and discuss how they impact observations. Finally, we discuss how they could have been prevented and should be in future observatories.",
"date": "2017-10",
"date_type": "published",
"publication": "Journal of Astronomical Telescopes, Instruments, and Systems",
"volume": "3",
"number": "4",
"publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)",
"pagerange": "Art. No. 044003",
"id_number": "CaltechAUTHORS:20180105-081533561",
"issn": "2329-4124",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180105-081533561",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1117/1.JATIS.3.4.044003",
"primary_object": {
"basename": "044003.pdf",
"url": "https://authors.library.caltech.edu/records/4n7y1-j6b02/files/044003.pdf"
},
"related_objects": [
{
"basename": "1711.02719.pdf",
"url": "https://authors.library.caltech.edu/records/4n7y1-j6b02/files/1711.02719.pdf"
}
],
"pub_year": "2017",
"author_list": "Madsen, Kristin K.; Christensen, Finn E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/69cen-dtb89",
"eprint_id": 84177,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:09:32",
"lastmod": "2026-04-01 08:02:34",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Hong-Jaesub",
"name": {
"family": "Hong",
"given": "Jaesub"
}
},
{
"id": "Allen-B",
"name": {
"family": "Allen",
"given": "Branden"
}
},
{
"id": "Grindlay-J-E",
"name": {
"family": "Grindlay",
"given": "Jonathan"
},
"orcid": "0000-0002-1323-5314"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Burnham-J-A",
"name": {
"family": "Burnham",
"given": "Jill"
}
},
{
"id": "Hong-Sankgi",
"name": {
"family": "Hong",
"given": "Sankgi"
}
},
{
"id": "Lei-Wesker",
"name": {
"family": "Lei",
"given": "Wesker"
}
},
{
"id": "Barthelmy-S-D",
"name": {
"family": "Barthelmy",
"given": "Scott"
}
},
{
"id": "Patti-R",
"name": {
"family": "Patti",
"given": "Robert"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona"
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "Through-Silicon-Vias (TSVs) for 3D readout of ASIC for nearly gapless CdZnTe detector arrays",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "Coded-aperture imaging, X-ray survey, Gamma-ray Burst, CdZnTe detectors",
"note": "\u00a9 2017 Society of Photo-Optical Instrumentation Engineers (SPIE).\n\nPublished - 103920U.pdf
",
"abstract": "Wirebonds, although proven for space application and perceived necessary for hybrid sensors like CdZnTe (CZT) detectors, introduce assembly complexity and undesirable gaps between detector units. Thus, they pose a serious challenge in building a low cost large area detector. We are developing Through-Silicon Vias (TSVs) to make all connections (both power and data) through ASICs, which will eliminate wirebonds and enable simple direct flip-chip bonding between the ASIC and a substrate electronics layer. TSVs also enable a more compact layout of the ASIC, which reduces the inactive area of the detector plane, and thus enables nearly gaplessly tilable detector arrays. We demonstrate the first successful TSV implementation on ASICs used for CZT detectors onboard the Nuclear Spectroscopic Telescope Array (NuSTAR) mission as part of our program to develop large area CZT imagers for wide field coded aperture imaging.",
"date": "2017-09-15",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers",
"id_number": "CaltechAUTHORS:20180108-153821651",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180108-153821651",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "Burger-A",
"name": {
"family": "Burger",
"given": "Arnold"
}
},
{
"id": "James-R-B",
"name": {
"family": "James",
"given": "Ralph B."
}
},
{
"id": "Fiederle-M",
"name": {
"family": "Fiederle",
"given": "Michael"
}
},
{
"id": "Franks-L",
"name": {
"family": "Franks",
"given": "Larry"
}
},
{
"id": "Payne-S-A",
"name": {
"family": "Payne",
"given": "Stephen A."
}
}
]
},
"doi": "10.1117/12.2274360",
"primary_object": {
"basename": "103920U.pdf",
"url": "https://authors.library.caltech.edu/records/69cen-dtb89/files/103920U.pdf"
},
"pub_year": "2017",
"author_list": "Hong, Jaesub; Allen, Branden; et al."
},
{
"id": "https://authors.library.caltech.edu/records/64vsf-rry57",
"eprint_id": 81304,
"eprint_status": "archive",
"datestamp": "2023-08-21 21:44:21",
"lastmod": "2026-04-01 20:40:41",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Chiavassa-A",
"name": {
"family": "Chiavassa",
"given": "A."
}
}
]
},
"title": "The Mass Function of GX 339\u20134 from Spectroscopic Observations of Its Donor Star",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "binaries: close; stars: individual (V821 Arae); X-rays: binaries",
"note": "\u00a9 2017 American Astronomical Society. \n\nReceived 2017 May 23. Accepted 2017 August 9. Published 2017 September 11. \n\nM.H. would like to thank Javier Garc\u00eda for valuable discussions. We would like to thank the ESO director for granting us DDT time for this project and the ESO staff for executing the observations. This research is based on observations made with ESO Telescopes at the La Silla Paranal Observatory under program IDs 097.D-0915 and 297.D-5048. It also made use of data obtained from the ESO Science Archive Facility, program ID 085.B-0751. This research made use of the software package Molly provided by Tom Marsh. M.A.P.T. acknowledges support via a Ramon y Cajal Fellowship (RYC-2015-17854).\n\nPublished - Heida_2017_ApJ_846_132.pdf
Submitted - 1708.04667.pdf
",
"abstract": "We obtained 16 VLT/X-shooter observations of GX 339\u22124 in quiescence during the period 2016 May\u2013September and detected absorption lines from the donor star in its NIR spectrum. This allows us to measure the radial velocity curve and projected rotational velocity of the donor for the first time. We confirm the 1.76 day orbital period and we find that K_2 = 219 \u00b1 3 km s^(\u22121), \u03b3 = 26 \u00b1 2 km s^(\u22121), and v sin i = 64 \u00b1 8 km s^(\u22121). From these values we compute a mass function f(M) = 1.91 \u00b1 0.08 M_\u2299, a factor ~3 lower than previously reported, and a mass ratio q = 0.18 \u00b1 0.05. We confirm the donor is a K-type star and estimate that it contributes ~ 4% - 50% of the light in the J- and H-bands. We constrain the binary inclination to 37\u00b0 < i < 78\u00b0 and the black hole (BH) mass to 2.3 M_\u2609 < M_(BH) < 9.5 M_\u2609. GX 339\u22124 may therefore be the first BH to fall in the \"mass-gap\" of 2\u20135 M_\u2299.",
"date": "2017-09-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "846",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 132",
"id_number": "CaltechAUTHORS:20170911-140345285",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170911-140345285",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Ram\u00f3n y Cajal Programme",
"grant_number": "RYC-2015-17854"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aa85df",
"primary_object": {
"basename": "1708.04667.pdf",
"url": "https://authors.library.caltech.edu/records/64vsf-rry57/files/1708.04667.pdf"
},
"related_objects": [
{
"basename": "Heida_2017_ApJ_846_132.pdf",
"url": "https://authors.library.caltech.edu/records/64vsf-rry57/files/Heida_2017_ApJ_846_132.pdf"
}
],
"pub_year": "2017",
"author_list": "Heida, M.; Jonker, P. G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/kbd3a-2rb61",
"eprint_id": 80896,
"eprint_status": "archive",
"datestamp": "2023-08-19 05:00:39",
"lastmod": "2025-06-30 18:38:06",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lansbury-G-B",
"name": {
"family": "Lansbury",
"given": "G. B."
},
"orcid": "0000-0002-5328-9827"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "The NuSTAR Serendipitous Survey: Hunting for the Most Extreme Obscured AGN at >10 keV",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: nuclei \u2013 quasars: general \u2013 surveys \u2013 X-rays: galaxies",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 March 10; revised 2017 July 19; accepted 2017 July 19; published 2017 August 28. \n\nThe authors first thank the anonymous referee for the positive and constructive review. We acknowledge support from a Herchel Smith Postdoctoral Research Fellowship of the University of Cambridge (G.B.L.); the Science and Technology Facilities Council (STFC) grants ST/I001573/1 (D.M.A.) and ST/J003697/2 (P.G.); the ERC Advanced Grant FEEDBACK 340442 at the University of Cambridge (J.A.); the NASA Earth and Space Science Fellowship Program, grant NNX14AQ07H (M.B.); CONICYT-Chile grants FONDECYT Regular 1141218 (F.E.B.), FONDECYT 1120061 and 1160999 (E.T.), and Anillo ACT1101 (F.E.B. and E.T.); the Center of Excellence in Astrophysics and Associated Technologies (PFB 06; F.E.B. and E.T.); the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to the Millennium Institute of Astrophysics, MAS (F.E.B.); ASI/INAF contract I/037/12/0-011/13 (A.C., A.M., and L.Z.); and Chandra grants GO5-16154X and GO6-17135X (J.A.T.). We thank Yoshihiro Ueda and Roberto Gilli for providing number counts predictions. This work was supported under NASA contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). \n\nFacilities: Chandra - , ESO La Silla - , Keck - , Magellan - , NuSTAR - , Palomar - , Pan-STARRS - , SDSS - , Swift - , WISE - , XMM-Newton.\n\nPublished - Lansbury_2017_ApJ_846_20.pdf
Submitted - 1707.06651.pdf
",
"abstract": "We identify sources with extremely hard X-ray spectra (i.e., with photon indices of \u0393 \u227e 0.6) in the 13 deg^2 NuSTAR serendipitous survey, to search for the most highly obscured active galactic nuclei (AGNs) detected at > 10 keV. Eight extreme NuSTAR sources are identified, and we use the NuSTARdata in combination with lower-energy X-ray observations (from Chandra, Swift XRT, and XMM-Newton) to characterize the broadband (0.5\u201324 keV) X-ray spectra. We find that all of the extreme sources are highly obscured AGNs, including three robust Compton-thick (CT; N_H > 1.5 x 10^(24) cm^(\u22122)) AGNs at low redshift (z < 0.1) and a likely CT AGN at higher redshift (z = 0.16). Most of the extreme sources would not have been identified as highly obscured based on the low-energy (< 10 keV) X-ray coverage alone. The multiwavelength properties (e.g., optical spectra and X-ray\u2013mid-IR luminosity ratios) provide further support for the eight sources being significantly obscured. Correcting for absorption, the intrinsic rest-frame 10\u201340 keV luminosities of the extreme sources cover a broad range, from \u22485 x 10^(42) to 10^(45) erg s^(\u22121). The estimated number counts of CT AGNs in the NuSTARserendipitous survey are in broad agreement with model expectations based on previous X-ray surveys, except for the lowest redshifts (z < 0.07), where we measure a high CT fraction of f^(obs)_(CT) = 30^(+16)_(-12)%. For the small sample of CT AGNs, we find a high fraction of galaxy major mergers (50% \u00b1 33%) compared to control samples of \"normal\" AGNs.",
"date": "2017-09-01",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "846",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 20",
"id_number": "CaltechAUTHORS:20170829-101443114",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170829-101443114",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "University of Cambridge"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/I001573/1"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/J003697/2"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1141218"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1120061"
},
{
"agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)",
"grant_number": "1160999"
},
{
"agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)",
"grant_number": "Anillo ACT1101"
},
{
"agency": "Center of Excellence in Astrophysics and Associated Technologies (CATA)",
"grant_number": "PFB 06"
},
{
"agency": "Iniciativa Cient\u00edfica Milenio del Ministerio de Econom\u00eda, Fomento y Turismo",
"grant_number": "IC120009"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0-011/13"
},
{
"agency": "NASA",
"grant_number": "GO5-16154X"
},
{
"agency": "NASA",
"grant_number": "GO6-17135X"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa8176",
"primary_object": {
"basename": "1707.06651.pdf",
"url": "https://authors.library.caltech.edu/records/kbd3a-2rb61/files/1707.06651.pdf"
},
"related_objects": [
{
"basename": "Lansbury_2017_ApJ_846_20.pdf",
"url": "https://authors.library.caltech.edu/records/kbd3a-2rb61/files/Lansbury_2017_ApJ_846_20.pdf"
}
],
"pub_year": "2017",
"author_list": "Lansbury, G. B.; Balokovi\u0107, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/xw82e-4sc41",
"eprint_id": 84003,
"eprint_status": "archive",
"datestamp": "2023-08-21 21:38:14",
"lastmod": "2024-01-14 19:15:39",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Smith-R-K",
"name": {
"family": "Smith",
"given": "R. K."
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Arcus: The X-ray Grating Spectrometer Explorer",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "Gratings; X-rays: spectroscopy; Instrumentation",
"note": "\u00a9 2017 SPIE. \n\nThe research leading to these results has in part received funding from the Smithsonian Astrophysical Observatory and the European Union's Horizon 2020 Program under the AHEAD project (grant agreement n. 654215). The Arcus team especially thanks the team at NASA's Marshall Space Flight Center's Stray Light Center for hosting the SPO and CAT testing, including substantial assistance with the data collection and analysis.\n\nPublished - 103970Q.pdf
",
"abstract": "Arcus, a Medium Explorer (MIDEX) mission, was selected by NASA for a Phase A study in August 2017. The observatory provides high-resolution soft X-ray spectroscopy in the 12-50\u00c5 bandpass with unprecedented sensitivity: effective areas of >450 cm^2 and spectral resolution >2500. The Arcus key science goals are (1) to measure the effects of structure formation imprinted upon the hot baryons that are predicted to lie in extended halos around galaxies, groups, and clusters, (2) to trace the propagation of outflowing mass, energy, and momentum from the vicinity of the black hole to extragalactic scales as a measure of their feedback and (3) to explore how stars, circumstellar disks and exoplanet atmospheres form and evolve. Arcus relies upon the same 12m focal length grazing-incidence silicon pore X-ray optics (SPO) that ESA has developed for the Athena mission; the focal length is achieved on orbit via an extendable optical bench. The focused X-rays from these optics are diffracted by high-efficiency Critical-Angle Transmission (CAT) gratings, and the results are imaged with flight-proven CCD detectors and electronics. The power and telemetry requirements on the spacecraft are modest. Mission operations are straightforward, as most observations will be long (~100 ksec), uninterrupted, and pre-planned, although there will be capabilities to observe sources such as tidal disruption events or supernovae with a ~3 day turnaround. Following the 2nd year of operation, Arcus will transition to a proposal-driven guest observatory facility.",
"date": "2017-08-29",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers",
"place_of_pub": "Bellingham, WA",
"pagerange": "Art. No. 103970Q",
"id_number": "CaltechAUTHORS:20171221-130042990",
"isbn": "978-1-5106-1252-5",
"book_title": "UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XX",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171221-130042990",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "654215"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "Siegmund-O-H-W",
"name": {
"family": "Siegmund",
"given": "Oswald H."
}
}
]
},
"doi": "10.1117/12.2272818",
"primary_object": {
"basename": "103970Q.pdf",
"url": "https://authors.library.caltech.edu/records/xw82e-4sc41/files/103970Q.pdf"
},
"pub_year": "2017",
"author_list": "Smith, R. K. and Madsen, K. K."
},
{
"id": "https://authors.library.caltech.edu/records/zbr1b-stc87",
"eprint_id": 84178,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:47:16",
"lastmod": "2024-01-14 19:15:53",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Smith-R-K",
"name": {
"family": "Smith",
"given": "R. K."
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "K. K."
},
"orcid": "0000-0003-1252-4891"
}
]
},
"title": "Arcus: exploring the formation and evolution of clusters, galaxies, and stars",
"ispublished": "unpub",
"full_text_status": "public",
"keywords": "Gratings, X-rays: spectroscopy, Instrumentation",
"note": "\u00a9 2017 Society of Photo-Optical Instrumentation Engineers (SPIE). n\n\nThe research leading to these results has in part received funding from the Smithsonian Astrophysical Observatory and the European Union's Horizon 2020 Program under the AHEAD project (grant agreement n. 654215). The Arcus team especially thanks the team at NASA's Marshall Space Flight Center's Stray Light Center for hosting the SPO and CAT testing, including substantial assistance with the data collection and analysis.\n\nPublished - 103970Q.pdf
",
"abstract": "Arcus, a Medium Explorer (MIDEX) mission, was selected by NASA for a Phase A study in August 2017. The observatory provides high-resolution soft X-ray spectroscopy in the 12-50\u00c5 bandpass with unprecedented sensitivity: effective areas of >450 cm^2 and spectral resolution >2500. The Arcus key science goals are (1) to measure the effects of structure formation imprinted upon the hot baryons that are predicted to lie in extended halos around galaxies, groups, and clusters, (2) to trace the propagation of outflowing mass, energy, and momentum from the vicinity of the black hole to extragalactic scales as a measure of their feedback and (3) to explore how stars, circumstellar disks and exoplanet atmospheres form and evolve. Arcus relies upon the same 12m focal length grazing-incidence silicon pore X-ray optics (SPO) that ESA has developed for the Athena mission; the focal length is achieved on orbit via an extendable optical bench. The focused X-rays from these optics are diffracted by high-efficiency Critical-Angle Transmission (CAT) gratings, and the results are imaged with flight-proven CCD detectors and electronics. The power and telemetry requirements on the spacecraft are modest. Mission operations are straightforward, as most observations will be long (~100 ksec), uninterrupted, and pre-planned, although there will be capabilities to observe sources such as tidal disruption events or supernovae with a ~3 day turnaround. Following the 2nd year of operation, Arcus will transition to a proposal-driven guest observatory facility.",
"date": "2017-08-29",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers",
"id_number": "CaltechAUTHORS:20180108-154902629",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180108-154902629",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Smithsonian Astrophysical Observatory"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "654215"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"contributors": {
"items": [
{
"id": "Siegmund-O-H-W",
"name": {
"family": "Siegmund",
"given": "Oswald H."
}
}
]
},
"doi": "10.1117/12.2272818",
"primary_object": {
"basename": "103970Q.pdf",
"url": "https://authors.library.caltech.edu/records/zbr1b-stc87/files/103970Q.pdf"
},
"pub_year": "2017",
"author_list": "Smith, R. K. and Madsen, K. K."
},
{
"id": "https://authors.library.caltech.edu/records/ce9q0-djr80",
"eprint_id": 84175,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:47:11",
"lastmod": "2026-04-01 20:25:35",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Bhalerao-V-B",
"name": {
"family": "Bhalerao",
"given": "Varun"
},
"orcid": "0000-0002-6112-7609"
},
{
"id": "Cook-W-R",
"name": {
"family": "Cook",
"given": "W. Rick"
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Kitaguchi-Takao",
"name": {
"family": "Kitaguchi",
"given": "Takao"
}
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Mao-Peter-H",
"name": {
"family": "Mao",
"given": "Peter H."
}
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "Hiromasa"
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Rana-V-R",
"name": {
"family": "Rana",
"given": "Vikram"
},
"orcid": "0000-0003-1703-8796"
}
]
},
"title": "Ground calibration of the spatial response and quantum efficiency of the CdZnTe hard x-ray detectors for NuSTAR",
"ispublished": "unpub",
"full_text_status": "public",
"note": "\u00a9 2017 Society of Photo-Optical Instrumentation Engineers (SPIE). \n\nThis work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration.\n\nPublished - 1039207.pdf
",
"abstract": "Pixelated Cadmium Zinc Telluride (CdZnTe) detectors are currently flying on the Nuclear Spectroscopic Telescope ARray (NuSTAR) NASA Astrophysics Small Explorer. While the pixel pitch of the detectors is \u2248 605 \u03bcm, we can leverage the detector readout architecture to determine the interaction location of an individual photon to much higher spatial accuracy. The sub-pixel spatial location allows us to finely oversample the point spread function of the optics and reduces imaging artifacts due to pixelation. In this paper we demonstrate how the sub-pixel information is obtained, how the detectors were calibrated, and provide ground verification of the quantum efficiency of our Monte Carlo model of the detector response.",
"date": "2017-08-29",
"date_type": "published",
"publisher": "Society of Photo-Optical Instrumentation Engineers",
"id_number": "CaltechAUTHORS:20180108-151123343",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180108-151123343",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"contributors": {
"items": [
{
"id": "Burger-A",
"name": {
"family": "Burger",
"given": "Arnold"
}
},
{
"id": "James-R-B",
"name": {
"family": "James",
"given": "Ralph B."
}
},
{
"id": "Fiederle-M",
"name": {
"family": "Fiederle",
"given": "Michael"
}
},
{
"id": "Franks-L",
"name": {
"family": "Franks",
"given": "Larry"
}
},
{
"id": "Payne-S-A",
"name": {
"family": "Payne",
"given": "Stephen A."
}
}
]
},
"doi": "10.1117/12.2271365",
"primary_object": {
"basename": "1039207.pdf",
"url": "https://authors.library.caltech.edu/records/ce9q0-djr80/files/1039207.pdf"
},
"pub_year": "2017",
"author_list": "Grefenstette, Brian W.; Bhalerao, Varun; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ytgbz-07k36",
"eprint_id": 80602,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:20:06",
"lastmod": "2026-04-01 20:29:49",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Park-Junghun",
"name": {
"family": "Park",
"given": "Junghun"
}
},
{
"id": "Southon-J",
"name": {
"family": "Southon",
"given": "John"
}
},
{
"id": "Fahrni-S",
"name": {
"family": "Fahrni",
"given": "Simon"
}
},
{
"id": "Creasman-P-P",
"name": {
"family": "Creasman",
"given": "Pearce Paul"
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "Richard"
},
"orcid": "0000-0003-2178-9111"
}
]
},
"title": "Relationship between solar activity and \u0394^(14)C peaks in AD 775, AD 994, and 660 BC",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "660 BC, AD 775, CME (coronal mass ejection), M12, solar energetic particles (SPE)",
"note": "\u00a9 2017 by the Arizona Board of Regents on behalf of the University of Arizona. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nPublished online: 19 June 2017. \n\nThis study was supported by a research project funded by the Ministry of Science, ICT and Future Planning of Korea. We are grateful for helpful and constructive comments from F Miyake and F Mekhaldi. The work at Caltech was supported by NASA under NNX13A66G, and subcontract 00008864 of NNX15AG09G, and by the NSF under grant AGS-1622487.\n\nPublished - relationship_between_solar_activity_and_14c_peaks_in_ad_775_ad_994_and_660_bc.pdf
Supplemental Material - urn_cambridge.org_id_binary_20170731112328969-0645_S0033822217000595_S0033822217000595sup001.docx
",
"abstract": "Since the AD 775 and AD 994 \u0394^(14)C peak (henceforth M12) was first measured by Miyake et al. (2012, 2013), several possible production mechanisms for these spike have been suggested, but the work of Mekhaldi et al. (2015) shows that a very soft energy spectrum was involved, implying that a strong solar energetic particle (SEP) event (or series of events) was responsible. Here we present \u0394^(14)C values from AD 721\u2013820 Sequoiadendron giganteum annual tree-ring samples from Sequoia National Park in California, USA, together with \u0394^(14)C in German oak from 650\u2013670 BC. The AD 721\u2013820 measurements confirm that a sharp \u0394^(14)C peak exists at AD 775, with a peak height of approximately 15\u2030 and show that this spike was preceded by several decades of rapidly decreasing \u0394^(14)C. A sharp peak is also present at 660 BC, with a peak height of about 10\u2030, and published data (Reimer et al. 2013) indicate that it too was preceded by a multi-decadal \u0394^(14)C decrease, suggesting that solar activity was very strong just prior to both \u0394^(14)C peaks and may be causally related. During periods of strong solar activity there is increased probability for coronal mass ejection (CME) events that can subject the Earth's atmosphere to high fluencies of solar energetic particles (SEPs). Periods of high solar activity (such as one in October\u2013November 2003) can also often include many large, fast CMEs increasing the probability of geomagnetic storms. In this paper we suggest that the combination of large SEP events and elevated geomagnetic activity can lead to enhanced production of ^(14)C and other cosmogenic isotopes by increasing the area of the atmosphere that is irradiated by high solar energetic particles.",
"date": "2017-08",
"date_type": "published",
"publication": "Radiocarbon",
"volume": "59",
"number": "04",
"publisher": "University of Arizona",
"pagerange": "1147-1156",
"id_number": "CaltechAUTHORS:20170818-085536951",
"issn": "0033-8222",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170818-085536951",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX13A66G"
},
{
"agency": "NASA",
"grant_number": "00008864NNX15AG09G"
},
{
"agency": "NSF",
"grant_number": "AGS-1622487"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1017/RDC.2017.59",
"primary_object": {
"basename": "relationship_between_solar_activity_and_14c_peaks_in_ad_775_ad_994_and_660_bc.pdf",
"url": "https://authors.library.caltech.edu/records/ytgbz-07k36/files/relationship_between_solar_activity_and_14c_peaks_in_ad_775_ad_994_and_660_bc.pdf"
},
"related_objects": [
{
"basename": "urn_cambridge.org_id_binary_20170731112328969-0645_S0033822217000595_S0033822217000595sup001.docx",
"url": "https://authors.library.caltech.edu/records/ytgbz-07k36/files/urn_cambridge.org_id_binary_20170731112328969-0645_S0033822217000595_S0033822217000595sup001.docx"
}
],
"pub_year": "2017",
"author_list": "Park, Junghun; Southon, John; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ef3a4-fa783",
"eprint_id": 77901,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:11:23",
"lastmod": "2026-04-01 21:06:32",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "D. R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Bauer-F-E",
"name": {
"family": "Bauer",
"given": "F. E."
},
"orcid": "0000-0002-8686-8737"
},
{
"id": "Boorman-P-G",
"name": {
"family": "Boorman",
"given": "P. G."
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Bucher-J",
"name": {
"family": "Buchner",
"given": "J."
},
"orcid": "0000-0003-0426-6634"
},
{
"id": "Brandt-W-N",
"name": {
"family": "Brandt",
"given": "W. N."
},
"orcid": "0000-0002-0167-2453"
},
{
"id": "Comastri-A",
"name": {
"family": "Comastri",
"given": "A."
},
"orcid": "0000-0003-3451-9970"
},
{
"id": "Del-Moro-A",
"name": {
"family": "Del Moro",
"given": "A."
}
},
{
"id": "Farrah-Duncan",
"name": {
"family": "Farrah",
"given": "D."
},
"orcid": "0000-0003-1748-2010"
},
{
"id": "Gandhi-Poshak",
"name": {
"family": "Gandhi",
"given": "P."
},
"orcid": "0000-0003-3105-2615"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Koss-M-J",
"name": {
"family": "Koss",
"given": "M."
},
"orcid": "0000-0002-7998-9581"
},
{
"id": "Lanz-L",
"name": {
"family": "Lanz",
"given": "L."
},
"orcid": "0000-0002-3249-8224"
},
{
"id": "Masini-A",
"name": {
"family": "Masini",
"given": "A."
},
"orcid": "0000-0002-7100-9366"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "C."
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "D."
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Vasudevan-R-V",
"name": {
"family": "Vasudevan",
"given": "R."
}
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
}
]
},
"title": "X-ray bolometric corrections for Compton-thick active galactic nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: nuclei \u2013 galaxies: Seyfert",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 March 3; revised 2017 May 17; accepted 2017 May 19; published 2017 July 17. \n\nWe thank the referee for providing a constructive review of our manuscript, which improved its quality. We also thank Kohei Ichikawa for insights into IR torus modeling and Almudena Alonso-Herrero and Pat Roche for providing the IR data for Figure 1. M. Balokovi\u0107 acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program, grant NNX14AQ07H. We acknowledge financial support from the ASI/INAF grant I/037/12/0\u2013011/13 (A.C., A.M.) and the Caltech Kingsley visitor program (A.C.). This work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. Furthermore, this research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. \n\nFacility: NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission.\n\nPublished - Brightman_2017_ApJ_844_10.pdf
Submitted - 1705.10804.pdf
",
"abstract": "We present X-ray bolometric correction factors, \u03ba_(Bol) (\u2261L_(Bol)/LX), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric output of the most obscured AGN. We adopt bolometric luminosities, L_(Bol), from literature infrared (IR) torus modeling and compile published intrinsic 2\u201310 keV X-ray luminosities, L_X, from X-ray torus modeling of NuSTAR data. Our sample consists of 10 local CT AGN where both of these estimates are available. We test for systematic differences in \u03ba_(Bol) values produced when using two widely used IR torus models and two widely used X-ray torus models, finding consistency within the uncertainties. We find that the mean \u03ba_(Bol) of our sample in the range L_(Bol)\u2248 10^(42)\u221210^(45) erg s^\u22121 is log_(10)\u03ba_(Bol) = 1.44\u00b10.12 with an intrinsic scatter of \u223c 0.2 dex, and that our derived \u03ba_(Bol) values are consistent with previously established relationships between \u03ba_(Bol) and L_(Bol) and \u03ba_(Bol) and Eddington ratio (\u03bb_(Edd)). We investigate if \u03ba_(Bol) is dependent on N_H by comparing our results on CT AGN to published results on less-obscured AGN, finding no significant dependence. Since many of our sample are megamaser AGN, known to be viewed edge-on, and furthermore under the assumptions of AGN unification whereby unobscured AGN are viewed face-on, our result implies that\nthe X-ray emitting corona is not strongly anisotropic. Finally, we present \u03ba_(Bol) values for CT AGN identified in X-ray surveys as a function of their observed L_X, where an estimate of their intrinsic L_X is not available, and redshift, useful for estimating the bolometric output of the most obscured AGN across cosmic time.",
"date": "2017-07-20",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "844",
"number": "1",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 10",
"id_number": "CaltechAUTHORS:20170601-152924591",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170601-152924591",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
},
{
"agency": "Agenzia Spaziale Italiana (ASI)",
"grant_number": "I/037/12/0\u2013011/13"
},
{
"agency": "Caltech Kingsley visitor program"
},
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa75c9",
"primary_object": {
"basename": "Brightman_2017_ApJ_844_10.pdf",
"url": "https://authors.library.caltech.edu/records/ef3a4-fa783/files/Brightman_2017_ApJ_844_10.pdf"
},
"related_objects": [
{
"basename": "1705.10804.pdf",
"url": "https://authors.library.caltech.edu/records/ef3a4-fa783/files/1705.10804.pdf"
}
],
"pub_year": "2017",
"author_list": "Brightman, M.; Balokovi\u0107, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ambpm-2ex62",
"eprint_id": 79077,
"eprint_status": "archive",
"datestamp": "2023-08-21 21:25:38",
"lastmod": "2026-04-01 19:57:59",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Mason-G-M",
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
}
]
},
"title": "Characteristics of Solar Energetic Ions as a Function of Longitude",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "acceleration of particles; interplanetary medium; solar\u2013terrestrial relations; Sun: coronal mass ejections, (CMEs); Sun: flares; Sun: particle emission",
"note": "\u00a9 2017 American Astronomical Society. \n\nReceived 2017 March 23. Accepted 2017 May 23. Published 2017 July 13. \n\nThe authors thank the STEREO/SEPT, STEREO/SECCHI, STEREO/WAVES, SOHO/EPHIN, Wind/WAVES, and SDO/AIA teams for making their data publicly available, Predicitve Science Inc. for their publicly available model-based field line tracing, L. Jian for her STEREO ICME list, and I. Richardson and H. Cane for their near-Earth ICME list. This work was supported by NSF grants 1156004 and 1156138 and NASA grants NNX11075G, NNX13AH66G, and NNX15AG09G. Work at Johns Hopkins University APL was supported by NASA grant NNX17AC05G/125225, and University of California Berkeley grant 00008934. This paper uses data from the CACTus CME catalog, generated and maintained by the SIDC at the Royal Observatory of Belgium; the Heliospheric Shock Database, generated and maintained at the University of Helsinki; and the SOHO CME catalog, generated and maintained at the CDAW Data Center by NASA and the Catholic University of America in cooperation with the Naval Research Laboratory (SOHO is a project of international cooperation between ESA and NASA). The GOES 8-15 particle data are produced in real time by the NOAA Space Weather Prediction Center (SWPC) and are distributed by the NOAA National Geophysical Data Center (NGDC).\n\nPublished - Cohen_2017_ApJ_843_132.pdf
",
"abstract": "Since the 2006 launch of STEREO, multi-spacecraft studies have yielded several surprising results regarding the spread of solar energetic particles (SEPs) within the inner heliosphere. We have investigated the role of energy and ridigity, using ACE and STEREO 10 MeV n^(\u22121) oxygen data to identify 41 large SEP events observed by two or three spacecraft. We calculated fluence spectra from ~0.1 to >10 MeV n^(\u22121) for H, He, O, and Fe for each event at the observing spacecraft (including SOHO and GOES). The particle fluences at 0.3, 1, and 10 MeV n^(\u22121) were examined as a function of the distance between the associated solar flare longitude and the spacecraft magnetic footpoints at the Sun to determine the longitudinal spread of particles and study how the distribution centers and widths depend on energy and charge-to-mass (Q/M) for the first time. On average, the three-spacecraft event distributions were centered at 22 \u00b1 4\u00b0 west of the flare site and were 43 \u00b1 1\u00b0 wide, though there was substantial variability, while the fit to the aggregate of the two-spacecraft event fluences yielded significantly wider distributions at 0.3 and 1 MeV n^(\u22121). The widths derived from both the three- and two-spacecraft events show an energy dependence with distributions narrowing with increasing energy, consistent with lower energy ions experiencing more field line co-rotation, or being accelerated over a larger portion of the CME-driven shock or for longer times as the shock expands. Surprisingly, no clear evidence was found for a Q/M dependence to the widths or centers suggesting that rigidity-related processes are not the dominant means of spreading particles in longitude.",
"date": "2017-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "843",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 132",
"id_number": "CaltechAUTHORS:20170713-101353720",
"issn": "1538-4357",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170713-101353720",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "AGS-1156004"
},
{
"agency": "NSF",
"grant_number": "AGS-1156138"
},
{
"agency": "NASA",
"grant_number": "NNX11075G"
},
{
"agency": "NASA",
"grant_number": "NNX13AH66G"
},
{
"agency": "NASA",
"grant_number": "NNX15AG09G"
},
{
"agency": "NASA",
"grant_number": "NNX17AC05G/125225"
},
{
"agency": "University of California Berkeley",
"grant_number": "00008934"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.3847/1538-4357/aa7513",
"primary_object": {
"basename": "Cohen_2017_ApJ_843_132.pdf",
"url": "https://authors.library.caltech.edu/records/ambpm-2ex62/files/Cohen_2017_ApJ_843_132.pdf"
},
"pub_year": "2017",
"author_list": "Cohen, C. M. S.; Mason, G. M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ta2bb-nn097",
"eprint_id": 77701,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:04:36",
"lastmod": "2026-04-01 20:45:03",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Zhang-Shuo",
"name": {
"family": "Zhang",
"given": "Shuo"
},
"orcid": "0000-0002-2967-790X"
},
{
"id": "Baganoff-F-K",
"name": {
"family": "Baganoff",
"given": "Frederick K."
}
},
{
"id": "Ponti-G",
"name": {
"family": "Ponti",
"given": "Gabriele"
},
"orcid": "0000-0003-0293-3608"
},
{
"id": "Neilsen-J",
"name": {
"family": "Neilsen",
"given": "Joseph"
},
"orcid": "0000-0002-8247-786X"
},
{
"id": "Tomsick-J-A",
"name": {
"family": "Tomsick",
"given": "John A."
},
"orcid": "0000-0001-5506-9855"
},
{
"id": "Dexter-J",
"name": {
"family": "Dexter",
"given": "Jason"
},
"orcid": "0000-0003-3903-0373"
},
{
"id": "Clavel-M",
"name": {
"family": "Clavel",
"given": "Ma\u00efca"
},
"orcid": "0000-0003-0724-2742"
},
{
"id": "Markoff-S",
"name": {
"family": "Markoff",
"given": "Sera"
},
"orcid": "0000-0001-9564-0876"
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "Charles J."
}
},
{
"id": "Mori-Kaya",
"name": {
"family": "Mori",
"given": "Kaya"
},
"orcid": "0000-0002-9709-5389"
},
{
"id": "Barri\u00e8re-N-M",
"name": {
"family": "Barri\u00e8re",
"given": "Nicolas M."
},
"orcid": "0000-0001-9407-9490"
},
{
"id": "Nowak-M-A",
"name": {
"family": "Nowak",
"given": "Michael A."
},
"orcid": "0000-0001-6923-1315"
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "Steven E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "Finn E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "William W."
}
},
{
"id": "Grefenstette-B-W",
"name": {
"family": "Grefenstette",
"given": "Brian W."
},
"orcid": "0000-0002-1984-2932"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "Fiona A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Madsen-K-K",
"name": {
"family": "Madsen",
"given": "Kristin K."
},
"orcid": "0000-0003-1252-4891"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "William W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "Sagittarius A* High Energy X-ray Flare Properties During NuSTAR Monitoring of the Galactic Center from 2012 to 2015",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "accretion, accretion disks \u2013 quasars: supermassive black holes \u2013 radiation mechanisms: non-thermal \u2013\nX-rays: individual (sgra)",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 April 12; revised 2017 May 19; accepted 2017 May 22; published 2017 July 10. \n\nThis work was supported under NASA Contract No. NNG08FD60C, and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). S.Z. acknowledges support by NASA Headquarters under the NASA Earth and Space Science Fellowship Program\u2014Grant \"NNX13AM31H.\" J.N. acknowledges funding from NASA through the Einstein Postdoctoral Fellowship, grant PF2-130097, awarded by the CXC, which is operated by the SAO for NASA under contract NAS8-03060. G.P. acknowledges support by the Bundesministerium f\u00fcr Wirtschaft und Technologie/Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (BMWI/DLR, FKZ 50 OR 1604) and the Max Planck Society. We thank all members of the Chandra Sgr A* XVP collaboration (http://www.sgra-star.com).\n\nPublished - Zhang_2017_ApJ_843_96.pdf
Submitted - 1705.08002.pdf
",
"abstract": "Understanding the origin of the flaring activity from the Galactic center supermassive black hole Sagittarius A* is a major scientific goal of the NuSTAR Galactic plane survey campaign. We report on the data obtained between 2012 July and 2015 April, including 27 observations on Sgr A*, with a total exposure of \u22431 Ms. We found a total of 10 X-ray flares detected in the NuSTAR observation window, with luminosities in the range of L_(3-79 keV) ~(0.2-4.0) x 10^(35) erg s^(-1). With this largest hard X-ray Sgr A* flare data set to date, we studied the flare spectral properties. Seven flares are detected above 5\u03c3 significance, showing a range of photon indices (\u0393 ~ 2.0\u20132.8) with typical uncertainties of \u00b10.5 (90% confidence level). We found no significant spectral hardening for brighter flares, as indicated by a smaller sample. The accumulation of all of the flare spectra in 1\u201379 keV can be well fit with an absorbed power-law model with \u0393 = 2.2 \u00b1 0.1, and does not require the existence of a spectral break. The lack of variation in the X-ray spectral index with luminosity would point to a single mechanism for the flares and is consistent with the synchrotron scenario. Lastly, we present the quiescent-state spectrum of Sgr A*, and derive an upper limit on the quiescent luminosity of Sgr A* above 10 keV to be L_(Xq,10-79 keV) \u2a7d (2.9 \u00b1 0.2) x 10^(34) erg s^(-1).",
"date": "2017-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "843",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 96",
"id_number": "CaltechAUTHORS:20170524-092936920",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170524-092936920",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNG08FD60C"
},
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NNX13AM31H"
},
{
"agency": "NASA Einstein Fellowship",
"grant_number": "PF2-130097"
},
{
"agency": "NASA",
"grant_number": "NAS8-03060"
},
{
"agency": "Bundesministerium f\u00fcr Wirtschaft und Technologie (BMWi)",
"grant_number": "FKZ 50 OR 1604"
},
{
"agency": "Max Planck Society"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa74e8",
"primary_object": {
"basename": "1705.08002.pdf",
"url": "https://authors.library.caltech.edu/records/ta2bb-nn097/files/1705.08002.pdf"
},
"related_objects": [
{
"basename": "Zhang_2017_ApJ_843_96.pdf",
"url": "https://authors.library.caltech.edu/records/ta2bb-nn097/files/Zhang_2017_ApJ_843_96.pdf"
}
],
"pub_year": "2017",
"author_list": "Zhang, Shuo; Baganoff, Frederick K.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/d4nqc-pre13",
"eprint_id": 77806,
"eprint_status": "archive",
"datestamp": "2023-08-21 21:25:15",
"lastmod": "2026-04-01 21:00:21",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kamraj-N",
"name": {
"family": "Kamraj",
"given": "N."
},
"orcid": "0000-0002-3233-2451"
},
{
"id": "Rivers-E",
"name": {
"family": "Rivers",
"given": "E."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Brightman-M",
"name": {
"family": "Brightman",
"given": "M."
},
"orcid": "0000-0002-8147-2602"
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
}
]
},
"title": "The NuSTAR View of the Seyfert 2 Galaxy NGC 4388",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active; galaxies: individual (NGC 4388); galaxies: Seyfert; X-rays: galaxies",
"note": "\u00a9 2017 The American Astronomical Society. \n\nReceived 2017 April 22; Accepted 2017 May 25; Published 2017 July 6. \n\nWe have made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). M. Balokovi\u0107 acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program, grant NNX14AQ07H. \n\nFacility: NuSTAR.\n\nPublished - Kamraj_2017_ApJ_843_89.pdf
Submitted - 1705.09260.pdf
",
"abstract": "We present an analysis of NuSTAR X-ray observations in the 3\u201379 keV energy band of the Seyfert 2 galaxy NGC 4388, taken in 2013. The broadband sensitivity of NuSTAR, covering the Fe K\u03b1 line and Compton reflection hump, enables tight constraints to be placed on reflection features in AGN X-ray spectra, thereby providing insight into the geometry of the circumnuclear material. In this observation, we found the X-ray spectrum of NGC 4388 to be well described by a moderately absorbed power law with non-relativistic reflection. We fit the spectrum with phenomenological reflection models and a physical torus model and find the source to be absorbed by Compton-thin material (N_H = (6.5 \u00b1 0.8) \u00d7 10^(23) cm^(\u22122)) with a very weak Compton reflection hump (R < 0.09) and an exceptionally large Fe K\u03b1 line (EW = 368^(+56)_(-53)\neV) for a source with weak or no reflection. Calculations using a thin-shell approximation for the expected Fe K\u03b1 EW indicate that an Fe K\u03b1 line originating from Compton-thin material presents a possible explanation.",
"date": "2017-07-10",
"date_type": "published",
"publication": "Astrophysical Journal",
"volume": "843",
"number": "2",
"publisher": "American Astronomical Society",
"pagerange": "Art. No. 89",
"id_number": "CaltechAUTHORS:20170526-095619685",
"issn": "0004-637X",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170526-095619685",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "NuSTAR"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.3847/1538-4357/aa7563",
"primary_object": {
"basename": "1705.09260.pdf",
"url": "https://authors.library.caltech.edu/records/d4nqc-pre13/files/1705.09260.pdf"
},
"related_objects": [
{
"basename": "Kamraj_2017_ApJ_843_89.pdf",
"url": "https://authors.library.caltech.edu/records/d4nqc-pre13/files/Kamraj_2017_ApJ_843_89.pdf"
}
],
"pub_year": "2017",
"author_list": "Kamraj, N.; Rivers, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/01nmc-pm458",
"eprint_id": 78527,
"eprint_status": "archive",
"datestamp": "2023-08-19 03:53:07",
"lastmod": "2026-04-01 15:29:16",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "L\u00f3pez-K-M",
"name": {
"family": "L\u00f3pez",
"given": "K. M."
}
},
{
"id": "Heida-M",
"name": {
"family": "Heida",
"given": "M."
},
"orcid": "0000-0002-1082-7496"
},
{
"id": "Jonker-P-G",
"name": {
"family": "Jonker",
"given": "P. G."
},
"orcid": "0000-0001-5679-0695"
},
{
"id": "Torres-M-A-P",
"name": {
"family": "Torres",
"given": "M. A. P."
}
},
{
"id": "Roberts-T-P",
"name": {
"family": "Roberts",
"given": "T. P."
},
"orcid": "0000-0001-8252-6337"
},
{
"id": "Walton-D-J",
"name": {
"family": "Walton",
"given": "D. J."
},
"orcid": "0000-0001-5819-3552"
},
{
"id": "Moon-Dae-Sik",
"name": {
"family": "Moon",
"given": "D.-S."
},
"orcid": "0000-0003-4200-5064"
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
}
]
},
"title": "A Systematic Search for Near-Infrared Counterparts of Nearby Ultraluminous X-ray sources (II)",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "stars: black holes \u2013 infrared: stars",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. \n\nAccepted 2017 April 3. Received 2017 April 3; in original form 2017 February 1. Published: 06 April 2017. \n\nThis research is based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof\u00edsica de Canarias. We have made use of the SIMBAD data base, operated at CDS, Strasbourg, France; of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration; and of data obtained from the Chandra Data Archive and the Chandra Source Catalog, and software provided by the Chandra X-ray Center (CXC) in the application packages CIAO, ChIPS and Sherpa. PGJ and KML acknowledge funding from the European Research Council under ERC Consolidator Grant agreement No. 647208. TPR acknowledges funding from Science & Technology Facilities Council (STFC) as part of the consolidated grant ST/L00075X/1.\n\nPublished - stx857.pdf
Submitted - 1704.01068.pdf
",
"abstract": "We present the results of our continued systematic search for near-infrared (NIR) candidate counterparts to ultraluminous X-ray sources (ULXs) within 10 Mpc. We observed 42 ULXs in 24 nearby galaxies and detected NIR candidate counterparts to 15 ULXs. Fourteen of these ULXs appear to have a single candidate counterpart in our images and the remaining ULX has two candidate counterparts. Seven ULXs have candidate counterparts with absolute magnitudes in the range between \u22129.26 and \u221211.18 mag, consistent with them being red supergiants (RSGs). The other eight ULXs have candidate counterparts with absolute magnitudes too bright to be a single stellar source. Some of these NIR sources show extended morphology or colours expected for active galactic nuclei (AGNs), strongly suggesting that they are likely stellar clusters or background galaxies. The RSG candidate counterparts form a valuable sample for follow-up spectroscopic observations to confirm their nature, with the ultimate goal of directly measuring the mass of the compact accretor that powers the ULX using binary Doppler shifts.",
"date": "2017-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "469",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "671-682",
"id_number": "CaltechAUTHORS:20170623-145105446",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170623-145105446",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "647208"
},
{
"agency": "Science and Technology Facilities Council (STFC)",
"grant_number": "ST/L00075X/1"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stx857",
"primary_object": {
"basename": "1704.01068.pdf",
"url": "https://authors.library.caltech.edu/records/01nmc-pm458/files/1704.01068.pdf"
},
"related_objects": [
{
"basename": "stx857.pdf",
"url": "https://authors.library.caltech.edu/records/01nmc-pm458/files/stx857.pdf"
}
],
"pub_year": "2017",
"author_list": "L\u00f3pez, K. M.; Heida, M.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/gasw7-5j711",
"eprint_id": 89232,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:19",
"lastmod": "2026-04-01 17:11:07",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "B. C."
}
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "N."
}
},
{
"id": "Webber-W-R",
"name": {
"family": "Webber",
"given": "W. R."
}
}
]
},
"title": "Anisotropy of Anomalous Cosmic Rays Observed by Voyager 2 in the Heliosheath",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nWe thank J. Richardson for providing the V2 PLS data. Voyager data analysis is supported by NASA Grant NNN12AA01C.\n\nPublished - ICRC2017_057.pdf
",
"abstract": "Voyager 2 (V2) has been observing anomalous cosmic rays (ACRs) in the heliosheath since August 2007 when V2 crossed the termination shock of the supersonic solar wind. We use the counting rate of ~0.5-35 MeV protons collected during periods when the spacecraft was rolling about the axis pointed to the Earth to infer their direction of flow. The observed flow velocity is the combination of the flow due to motion of heliosheath plasma and a diffusive flow due to a gradient in the ACR intensity. The latitudinal component of the flow (N component) agrees with the convective flow due to the heliospheric plasma flow as determined by the plasma instrument on V2. However, the tangential component of the flow (T component) is smaller than the predicted convective flow, consistent with an intensity gradient in the +T direction and a diffusive flow of ACRs from a source located in the +T direction. This would be consistent with models predicting that the acceleration of higher energy ACRs occurs along the flanks or tail of the heliosphere. A similar result was obtained by analysis of the V1 magrol data during V1's journey through the heliosheath [1].",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122924831",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122924831",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNN12AA01C"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.22323/1.301.0057",
"primary_object": {
"basename": "ICRC2017_057.pdf",
"url": "https://authors.library.caltech.edu/records/gasw7-5j711/files/ICRC2017_057.pdf"
},
"pub_year": "2017",
"author_list": "Stone, E. C.; Cummings, A. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/557tf-b1y27",
"eprint_id": 89250,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:51",
"lastmod": "2026-03-18 04:50:02",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Burnham-J-A",
"name": {
"family": "Burnham",
"given": "J. A."
}
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cook-W-R",
"name": {
"family": "Cook",
"given": "W. R."
}
},
{
"id": "Crabill-R-M",
"name": {
"family": "Crabill",
"given": "R. M."
}
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"id": "Hernandez-L",
"name": {
"family": "Hernandez",
"given": "L."
}
},
{
"id": "Kecman-B",
"name": {
"family": "Kecman",
"given": "B."
}
},
{
"id": "Klemic-J",
"name": {
"family": "Klemic",
"given": "J."
}
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Lopez-S",
"name": {
"family": "Lopez",
"given": "S."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Miyasaka-Hiromasa",
"name": {
"family": "Miyasaka",
"given": "H."
},
"orcid": "0000-0002-8074-4186"
},
{
"id": "Rankin-J-S",
"name": {
"family": "Rankin",
"given": "J. S."
},
"orcid": "0000-0002-8111-1444"
},
{
"id": "Riggans-G",
"name": {
"family": "Riggans",
"given": "G."
}
},
{
"id": "Rusert-M-D",
"name": {
"family": "Rusert",
"given": "M. D."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "White-M-L",
"name": {
"family": "White",
"given": "M. L."
}
}
]
},
"title": "Capabilities and Performance of the High-Energy Energetic-Particles Instrument for the Parker Solar Probe Mission",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nWe thank C. Anderson and D. Miles for administrative support at Caltech, Micron Semiconductor, Ltd. for developing the EPI-Hi detectors, D. Aalami of Space Instruments for developing the bias supply, and the cyclotron laboratories at Michigan State University, Texas A&M University, and the Lawrence Berkeley National Laboratory for providing calibration beams. Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, with support from the National Aeronautics and Space Administration.\n\nPublished - ICRC2017_016.pdf
",
"abstract": "NASA's Parker Solar Probe (PSP) spacecraft (formerly Solar Probe Plus) is scheduled for launch in July 2018 with a planned heliocentric orbit that will carry it on a series of close passes by the Sun with perihelion distances that eventually will get below 10 solar radii. Among other in-situ and imaging sensors, the PSP payload includes the two-instrument \"Integrated Science Investigation of the Sun\" suite, which will make coordinated measurements of energetic ions and electrons. The high-energy instrument (EPI-Hi), operating in the MeV energy range, consists of three detector-telescopes using silicon solid-state sensors for measuring composition, energy spectra, angular distributions, and time structure in solar energetic particle events. The expected performance of this instrument has been studied using accelerator calibrations, radioactive-source tests, and simulations. We present the EPI-Hi measurement capabilities drawing on these calibration data and simulation results for illustrations.",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122926697",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122926697",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.22323/1.301.0016",
"primary_object": {
"basename": "ICRC2017_016.pdf",
"url": "https://authors.library.caltech.edu/records/557tf-b1y27/files/ICRC2017_016.pdf"
},
"pub_year": "2017",
"author_list": "Wiedenbeck, M. E.; Burnham, J. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/7bw79-21415",
"eprint_id": 89245,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:34",
"lastmod": "2026-04-01 06:51:30",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "von-Rosenvinge-T-T",
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
}
]
},
"title": "Magnetic Fluctuations and Peculiar Anisotropy Oscillations in the 23 July 2012 SEP Event",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nThis work was supported by the National Aeronautics and Space Administration (NASA) at the California Institute of Technology and the Jet Propulsion Laboratory under sub-contract 00008864 from the University of California at Berkeley under NASA grant NNX15AG09G. We thank the STEREO/MAG team for making their data publicly available, and we thank Andrew Davis and Chris Russell for help in understanding the LET and MAG data timetags.\n\nPublished - ICRC2017_144.pdf
",
"abstract": "The pitch-angle distributions of solar energetic particles (SEPs) provide a wealth of information about particle transport through interplanetary space, and depend on the magnetic field strength, topology, and turbulence at remote heliospheric locations. The Low Energy Telescope (LET) on STEREO measures angular distributions in the ecliptic for SEP ions from protons to iron with energies of about 2--12 MeV/nucleon. At the onset of the 23 July 2012 extreme SEP event, a beamed distribution was observed at STEREO-Ahead using LET. We have previously reported apparent \"oscillations\" in the pitch-angle width of this beam when using simultaneous particle and magnetic field measurements at a 1-minute cadence. We have now determined that this behavior is largely a result of the effects of magnetic turbulence on the calculated particle pitch angle distributions. The locally measured magnetic field direction varies relatively rapidly, while the energetic particle distribution is governed by magnetic fields averaged over much larger spatial and temporal scales than represented by solar wind measurements at the same cadence. Similar behavior in earlier events has been reported by others and analyzed in the framework of quasilinear theory.",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122926202",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122926202",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "00008864"
},
{
"agency": "NASA",
"grant_number": "NNX15AG09G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.22323/1.301.0144",
"primary_object": {
"basename": "ICRC2017_144.pdf",
"url": "https://authors.library.caltech.edu/records/7bw79-21415/files/ICRC2017_144.pdf"
},
"pub_year": "2017",
"author_list": "Leske, R. A.; Cummings, A. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/5t0q6-hy404",
"eprint_id": 89241,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:24",
"lastmod": "2026-04-01 06:51:35",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Walsh-N-E",
"name": {
"family": "Walsh",
"given": "N. E."
}
},
{
"id": "Binns-W-R",
"name": {
"family": "Binns",
"given": "W. R."
},
"orcid": "0000-0001-6110-3407"
},
{
"id": "Israel-M-H",
"name": {
"family": "Israel",
"given": "M. H."
},
"orcid": "0000-0002-8104-208X"
},
{
"id": "Murphy-R-P",
"name": {
"family": "Murphy",
"given": "R. P."
}
},
{
"id": "Rauch-B-F",
"name": {
"family": "Rauch",
"given": "B. F."
}
},
{
"id": "Ward-J-E",
"name": {
"family": "Ward",
"given": "J. E."
}
},
{
"id": "Brandt-T-J",
"name": {
"family": "Brandt",
"given": "T. J."
},
"orcid": "0000-0003-4087-1786"
},
{
"id": "Link-J-T",
"name": {
"family": "Link",
"given": "J. T."
}
},
{
"id": "Mitchell-J-W",
"name": {
"family": "Mitchell",
"given": "J. W."
}
},
{
"id": "Hams-T",
"name": {
"family": "Hams",
"given": "T."
}
},
{
"id": "Sakai-Kenichi",
"name": {
"family": "Sakai",
"given": "K."
}
},
{
"id": "Sasaki-Makoto",
"name": {
"family": "Sasaki",
"given": "M."
}
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Waddington-C-J",
"name": {
"family": "Waddington",
"given": "C. J."
}
}
]
},
"title": "Preliminary SuperTIGER Abundances of Galactic Cosmic-Rays for the Charge Interval Z=41-56 and Prospects for SuperTIGER-2",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.\n\nPublished - ICRC2017_201.pdf
",
"abstract": "The SuperTIGER (Trans-Iron Galactic Element Recorder) instrument was launched from Williams Field, Antarctica on December 8, 2012 and flew for 55 days at a mean altitude of 125,000 feet on a long-duration balloon flight. SuperTIGER measured the relative abundances of Galactic cosmic-ray nuclei with high statistical precision and well resolved individual element peaks in the charge range Z=10-40. In addition, SuperTIGER made exploratory measurements of the relative abundances up to Z=56. Although the statistics are low for charges greater than Z=40, we will show how the relative abundances of charges Z=40-56 compare to those reported by HEAO3. A second flight, SuperTIGER-II, is planned for December 2017. As SuperTIGER-II will fly during solar minimum, we estimate a ~50% increase in the particles collected per unit time as compared to SuperTIGER-I. With the combined data sets of SuperTIGER-I and II we will improve statistics in the Z=30-40 range and measure individual elemental abundances up to Z=56.",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122925735",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122925735",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.22323/1.301.0201",
"primary_object": {
"basename": "ICRC2017_201.pdf",
"url": "https://authors.library.caltech.edu/records/5t0q6-hy404/files/ICRC2017_201.pdf"
},
"pub_year": "2017",
"author_list": "Walsh, N. E.; Binns, W. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/jn2h5-yxv79",
"eprint_id": 89242,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:29",
"lastmod": "2026-04-01 15:32:09",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Sollitt-L-S",
"name": {
"family": "Sollitt",
"given": "L. S."
}
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Mason-G-M",
"name": {
"family": "Mason",
"given": "G. M."
},
"orcid": "0000-0003-2169-9618"
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "von-Rosenvinge-T-T",
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
},
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
}
]
},
"title": "Reanalyzing Inferred High Energy Ionic Charge States for Solar Energetic Particle Events from 2005-2016 with ACE and STEREO",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nThis work was supported by NASA grant NNX13A66G and NASA contract NA55-03131.\n\nPublished - ICRC2017_097.pdf
",
"abstract": "We have estimated mean high-energy ionic charge states of solar energetic particles (SEPs) using the Sollitt et al. (2008) method. In our analysis, the method applies to abundant elements (e.g. N, O, Ne, Mg, Si, and Fe) in SEP events at the energy ranges covered by the STEREO/LET instrument (e.g. 2.7-70 MeV/nuc for Fe) and the ACE/SIS instrument (e.g. 11-168 MeV/nuc for Fe). The method starts by fitting SEP time-intensity profiles during the decay phase of a given, large SEP event in order to obtain energy-dependent decay times. The energy dependence of intensity decay times for a given element in an SEP event is combined with its assumed average atomic mass and an assumed average charge state of 5.9 for carbon as a reference element. The mean charge state for each element is then estimated from the relationship between the energy dependence of its decay times to that for carbon and all other elements in the event. The method has yielded charge states for 8 SEP events using ACE data, 5 SEP events with STEREO A data, and 4 SEP events with STEREO B data through 2015. Calculations for events before 2005 by Sollitt et al. using ACE data also incorporated helium time intensity profile fits, with an assumed charge state of 2, but later calculations dropped helium as a reference element for simplicity, as the calculations were first generalized to later events and to STEREO data. In this paper, we restore helium in order to refine the calculations and compare with the earlier results. In particular, we will focus on the 8 March 2012 event with ACE/SIS data and the 28 September 2012 event with STEREO/LET data. Additionally, other charge state measurements using a geomagnetic rigidity cutoff technique yielded correlations between charge states and Fe/O ratio as well as to observed source solar longitudes. We will use the inferred charge state reanalysis to investigate whether these correlations are also present in ACE and STEREO data.",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122925836",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122925836",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX13A66G"
},
{
"agency": "NASA",
"grant_number": "NA55-03131"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.22323/1.301.0097",
"primary_object": {
"basename": "ICRC2017_097.pdf",
"url": "https://authors.library.caltech.edu/records/jn2h5-yxv79/files/ICRC2017_097.pdf"
},
"pub_year": "2017",
"author_list": "Labrador, A. W.; Sollitt, L. S.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/mz711-4fe02",
"eprint_id": 89247,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:40",
"lastmod": "2026-04-01 06:25:19",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Wiedenbeck-M-E",
"name": {
"family": "Wiedenbeck",
"given": "M. E."
},
"orcid": "0000-0002-2825-3128"
},
{
"id": "Binns-W-R",
"name": {
"family": "Binns",
"given": "W. R."
},
"orcid": "0000-0001-6110-3407"
},
{
"id": "Israel-M-H",
"name": {
"family": "Israel",
"given": "M. H."
},
"orcid": "0000-0002-8104-208X"
},
{
"id": "Leske-R-A",
"name": {
"family": "Leske",
"given": "R. A."
},
"orcid": "0000-0002-0156-2414"
},
{
"id": "Christian-E-R",
"name": {
"family": "Christian",
"given": "E. R."
},
"orcid": "0000-0003-2134-3937"
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Davis-A-J",
"name": {
"family": "Davis",
"given": "A. J."
}
},
{
"id": "de-Nolfo-G-A",
"name": {
"family": "de Nolfo",
"given": "G. A."
},
"orcid": "0000-0002-3677-074X"
},
{
"id": "Labrador-A-W",
"name": {
"family": "Labrador",
"given": "A. W."
},
"orcid": "0000-0001-9178-5349"
},
{
"id": "Lave-K-A",
"name": {
"family": "Lave",
"given": "K. A."
}
},
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "von-Rosenvinge-T-T",
"name": {
"family": "von Rosenvinge",
"given": "T. T."
}
}
]
},
"title": "Recent Results from the Cosmic Ray Isotope Spectrometer on NASA's Advanced Composition Explorer",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nWe thank G. Morlino and V. Ptuskin for helpful comments on the application of propagation models to derive of the source ratio ^(60)Fe/^(56)Fe. \n\nThe research was carried out with support from the National Aeronautics and Space Administration at the California Institute of Technology (under grant NNX13AH66G), the Jet Propulsion Laboratory, Washington University in St. Louis, and the Goddard Space Flight Center.\n\nPublished - ICRC2017_1089.pdf
",
"abstract": "The Advanced Composition Explorer (ACE), which carries instrumentation for making high-precision measurements of the charge and mass of energetic nuclei between \u223c1 keV/nuc and \u223c1 GeV/nuc, was launched in August 1997 into an orbit about the L1 Lagrangian point 1.5 million km sunward of the Earth. From this vantage point, ACE collects data that are used for a wide range of studies in galactic and heliospheric physics. The ACE spacecraft and instruments are, for the most part, continuing to perform very well and to extend their data sets. The long mission duration, which is already almost an order of magnitude greater than the two years that was nominally required of ACE, has made it possible to address science topics beyond those envisioned when the mission was proposed. In this paper we address several topics to which ACE's Cosmic Ray Isotope Spectrometer (CRIS) is contributing in the area of galactic cosmic radiation. CRIS has been able to make measurements of extremely rare species, including the primary radioactive nuclide 60Fe and a number of stable \"ultraheavy\" elements with atomic numbers in the range Z=30 to 40. In addition, elemental energy spectra have now been measured over a significant fraction of two solar cycles, thereby enabling studies of the time dependence of the solar modulation of galactic cosmic rays.",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122926410",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122926410",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA/JPL/Caltech"
},
{
"agency": "NASA",
"grant_number": "NNX13AH66G"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Physics-Department"
}
]
},
"doi": "10.22323/1.301.1089",
"primary_object": {
"basename": "ICRC2017_1089.pdf",
"url": "https://authors.library.caltech.edu/records/mz711-4fe02/files/ICRC2017_1089.pdf"
},
"pub_year": "2017",
"author_list": "Wiedenbeck, M. E.; Binns, W. R.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/r2r9q-myg16",
"eprint_id": 75576,
"eprint_status": "archive",
"datestamp": "2023-08-19 03:48:10",
"lastmod": "2026-04-01 17:16:12",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Kara-E",
"name": {
"family": "Kara",
"given": "E."
},
"orcid": "0000-0003-0172-0854"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "J. A."
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Lohfink-A",
"name": {
"family": "Lohfink",
"given": "A."
}
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "A. C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Reynolds-C-S",
"name": {
"family": "Reynolds",
"given": "C. S."
}
},
{
"id": "Tombesi-F",
"name": {
"family": "Tombesi",
"given": "F."
},
"orcid": "0000-0002-6562-8654"
},
{
"id": "Wilkins-D-R",
"name": {
"family": "Wilkins",
"given": "D. R."
}
}
]
},
"title": "The high-Eddington NLS1 Ark 564 has the coolest corona",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: active \u2013 X-rays: individual: Ark 564",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. \n\nAccepted 2017 March 28. Received 2017 March 27; in original form 2017 January 17. Published: 30 March 2017. \n\nEK thanks Julian Malzac, Pierre-Olivier Petrucci, Andrea Marinucci and the participants of the FERO8 meeting in Moravia, Czech Republic for interesting discussions on accretion disc coronae. EK thanks the NuSTAR GO Programme for support under grant NNX15AV26G. EK thanks the Hubble Fellowship Programme. Support for Programme number HST-HF2-51360.001-A was provided by NASA through a Hubble Fellowship grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. ACF acknowledges ERC Advanced Grant 340442. CSR acknowledges support from NASA under grant NNX17AF29G.\n\nPublished - stx792.pdf
Submitted - 1703.09815.pdf
",
"abstract": "Ark 564 is an archetypal Narrow line Seyfert 1 that has been well observed in\nsoft X-rays from 0.3-10 keV, revealing a steep spectrum, strong soft excess,\niron K emission line and dramatic variability on the order of hours. Because of\nits very steep spectrum, observations of the source above 10 keV have been\nsparse. We report here on the first NuSTAR observation of Ark 564. The source\nwas observed for 200 ks with NuSTAR, 50 ks of which were concurrent with Suzaku\nobservations. NuSTAR and Suzaku observed a dramatic flare, in which the hard\nemission is clearly delayed with respect to the soft emission, consistent with\nprevious detections of a low-frequency hard lag found in XMM-Newton data. The\nNuSTAR spectrum is well described by a low-temperature Comptonisation continuum\n(with an electron temperature of 15 +/- 2 keV), which irradiates a highly\nionised disc. No further relativistic broadening or ionized absorption is\nrequired. These spectral results show that Ark 564 has one of the lowest\ntemperature coronae observed by NuSTAR to date. We discuss possible reasons for\nlow-temperature coronae in high-Eddington sources.",
"date": "2017-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "468",
"number": "3",
"publisher": "Royal Astronomical Society",
"pagerange": "3489-3498",
"id_number": "CaltechAUTHORS:20170331-101614336",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170331-101614336",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NASA",
"grant_number": "NNX15AV26G"
},
{
"agency": "NASA Hubble Fellowship"
},
{
"agency": "NASA",
"grant_number": "HST-HF2-51360.001-A"
},
{
"agency": "NASA",
"grant_number": "NAS5-26555"
},
{
"agency": "European Research Council (ERC)",
"grant_number": "340442"
},
{
"agency": "NASA",
"grant_number": "NNX17AF29G"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stx792",
"primary_object": {
"basename": "1703.09815.pdf",
"url": "https://authors.library.caltech.edu/records/r2r9q-myg16/files/1703.09815.pdf"
},
"related_objects": [
{
"basename": "stx792.pdf",
"url": "https://authors.library.caltech.edu/records/r2r9q-myg16/files/stx792.pdf"
}
],
"pub_year": "2017",
"author_list": "Kara, E.; Garc\u00eda, J. A.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/508r1-mfq34",
"eprint_id": 75587,
"eprint_status": "archive",
"datestamp": "2023-08-19 03:48:17",
"lastmod": "2026-04-01 05:54:43",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Garc\u00eda-Bernete-I",
"name": {
"family": "Garc\u00eda-Bernete",
"given": "I."
}
},
{
"id": "Ramos-Almeida-C",
"name": {
"family": "Ramos Almeida",
"given": "C."
}
},
{
"id": "Landt-H",
"name": {
"family": "Landt",
"given": "H."
}
},
{
"id": "Ward-M-J",
"name": {
"family": "Ward",
"given": "M. J."
}
},
{
"id": "Balokovi\u0107-M",
"name": {
"family": "Balokovi\u0107",
"given": "M."
},
"orcid": "0000-0003-0476-6647"
},
{
"id": "Acosta-Pulido-J-A",
"name": {
"family": "Acosta-Pulido",
"given": "J. A."
}
}
]
},
"title": "The infrared to X-ray correlation spectra of unobscured type 1 active galactic nuclei",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "galaxies: active \u2013 galaxies: nuclei \u2013 infrared: galaxies \u2013X-rays: galaxies",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. \n\nAccepted 2017 March 28. Received 2017 March 28; in original form 2017 January 26. Published: 01 April 2017. \n\nIGB acknowledges financial support from the Instituto de Astrof\u00edsica de Canarias through Fundaci\u00f3n La Caixa. IGB also acknowledges the Durham University for their hospitality during his stay in 2015 March and April when this project was started. CRA acknowledges the Ram\u00f3n y Cajal Program of the Spanish Ministry of Economy and Competitiveness through project RYC-2014-15779 and also the Plan Nacional project AYA2016-76682-C3-2-P. MB acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program, grant NNX14AQ07H. We finally acknowledge useful comments from the anonymous referee.\n\nPublished - stx795.pdf
Submitted - 1703.09660.pdf
",
"abstract": "We use new X-ray data obtained with the Nuclear Spectroscopic Telescope Array (NuSTAR), near-infrared (NIR) fluxes and mid-infrared (MIR) spectra of a sample of 24 unobscured type 1 active galactic nuclei (AGN) to study the correlation between various hard X-ray bands between 3 and 80 keV and the infrared (IR) emission. The IR to X-ray correlation spectrum (IRXCS) shows a maximum at \u223c15\u201320 \u03bcm, coincident with the peak of the AGN contribution to the MIR spectra of the majority of the sample. There is also an NIR correlation peak at \u223c2 \u03bcm, which we associate with the NIR bump observed in some type 1 AGN at \u223c1\u20135 \u03bcm and is likely produced by nuclear hot dust emission. The IRXCS shows practically the same behaviour in all the X-ray bands considered, indicating a common origin for all of them. We finally evaluated correlations between the X-ray luminosities and various MIR emission lines. All the lines show a good correlation with the hard X-rays (\u03c1 \u2265 0.7), but we do not find the expected correlation between their ionization potentials and the strength of the IRXCS.",
"date": "2017-07",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "469",
"number": "1",
"publisher": "Royal Astronomical Society",
"pagerange": "110-126",
"id_number": "CaltechAUTHORS:20170331-105830442",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170331-105830442",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Fundaci\u00f3n La Caixa"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "RYC-2014-15779"
},
{
"agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)",
"grant_number": "AYA2016-76682-C3-2-P"
},
{
"agency": "NASA Earth and Space Science Fellowship",
"grant_number": "NNX14AQ07H"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.1093/mnras/stx795",
"primary_object": {
"basename": "1703.09660.pdf",
"url": "https://authors.library.caltech.edu/records/508r1-mfq34/files/1703.09660.pdf"
},
"related_objects": [
{
"basename": "stx795.pdf",
"url": "https://authors.library.caltech.edu/records/508r1-mfq34/files/stx795.pdf"
}
],
"pub_year": "2017",
"author_list": "Garc\u00eda-Bernete, I.; Ramos Almeida, C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/ek5zy-2m631",
"eprint_id": 89231,
"eprint_status": "archive",
"datestamp": "2023-08-19 04:00:14",
"lastmod": "2026-04-01 07:50:59",
"type": "book_section",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Mewaldt-R-A",
"name": {
"family": "Mewaldt",
"given": "R. A."
},
"orcid": "0000-0003-2178-9111"
},
{
"id": "Li-Gang",
"name": {
"family": "Li",
"given": "G."
},
"orcid": "0000-0001-9313-251X"
},
{
"id": "Hu-Junxiang",
"name": {
"family": "Hu",
"given": "J."
}
},
{
"id": "Cohen-C-M-S",
"name": {
"family": "Cohen",
"given": "C. M. S."
},
"orcid": "0000-0002-0978-8127"
}
]
},
"title": "What is Causing the Deficit of High-Energy Solar Particles in Solar Cycle 24?",
"ispublished": "unpub",
"full_text_status": "public",
"note": "Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \n\nWork at Caltech and the University of Alabama/Huntsville was funded by a SHINE Collaborative Research grant under NSF Grant 1622487. In addition, Caltech was funded in part by NASA grants NNZ13AH66G and NNX15AG09G, and UA Huntsville was funded in part by NSF grant AGS-1622391, NASA grants NNX15AJ93G and NNX14AC08G, and by a 2013-2014 IIDR grant at UAH.\n\nPublished - ICRC2017_111.pdf
",
"abstract": "The number of large Solar Energetic Particle (SEP) events in solar cycle 24 is reduced by a factor of about 2 compared to cycle 23. In the first 8 years of this cycle there have been only 38 \"GOES\" proton events compared to 79 at this point of cycle 23. What is less well known is that the fluence of protons and heavier ions is reduced by even greater factors (by 6 times for greater than 10 MeV protons, and by 9 times for greater than 100 MeV protons). Indeed the spectral breaks for H, O, and Fe are all occurring about 3 times lower in energy/nucleon in cycle 24. This talk will investigate the reduced acceleration efficiency in cycle 24 by simulating SEP acceleration using the Particle Acceleration and Transport in the Heliosphere (PATH) model, and an improved version known as iPATH, which simulates SEP acceleration at a CME-driven shock in two dimensions. Specifically, we will investigate how SEP fluences and energy spectra depend on variables that include the interplanetary magnetic field strength and turbulence level, and the density and spectrum of suprathermal seed particles.",
"date": "2017-07",
"date_type": "published",
"publisher": "SISSA",
"id_number": "CaltechAUTHORS:20180828-122924747",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180828-122924747",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "NSF",
"grant_number": "AGS-1622487"
},
{
"agency": "NASA",
"grant_number": "NNZ13AH66G"
},
{
"agency": "NASA",
"grant_number": "NNX15AG09G"
},
{
"agency": "NSF",
"grant_number": "AGS-1622391"
},
{
"agency": "NASA",
"grant_number": "NNX15AJ93G"
},
{
"agency": "NASA",
"grant_number": "NNX14AC08G"
},
{
"agency": "University of Alabama in Huntsville"
}
]
},
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.22323/1.301.0111",
"primary_object": {
"basename": "ICRC2017_111.pdf",
"url": "https://authors.library.caltech.edu/records/ek5zy-2m631/files/ICRC2017_111.pdf"
},
"pub_year": "2017",
"author_list": "Mewaldt, R. A.; Li, G.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/8cbe7-xpk65",
"eprint_id": 75099,
"eprint_status": "archive",
"datestamp": "2023-08-19 03:42:29",
"lastmod": "2026-04-01 20:21:31",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Ponti-G",
"name": {
"family": "Ponti",
"given": "G."
},
"orcid": "0000-0003-0293-3608"
},
{
"id": "George-E",
"name": {
"family": "George",
"given": "E."
}
},
{
"id": "Scaringi-S",
"name": {
"family": "Scaringi",
"given": "S."
}
},
{
"id": "Zhang-S",
"name": {
"family": "Zhang",
"given": "S."
}
},
{
"id": "Jin-C",
"name": {
"family": "Jin",
"given": "C."
}
},
{
"id": "Dexter-J",
"name": {
"family": "Dexter",
"given": "J."
},
"orcid": "0000-0003-3903-0373"
},
{
"id": "Terrier-R",
"name": {
"family": "Terrier",
"given": "R."
}
},
{
"id": "Clavel-M",
"name": {
"family": "Clavel",
"given": "M."
},
"orcid": "0000-0003-0724-2742"
},
{
"id": "Degenaar-N",
"name": {
"family": "Degenaar",
"given": "N."
}
},
{
"id": "Eisenhauer-F",
"name": {
"family": "Eisenhauer",
"given": "F."
}
},
{
"id": "Genzel-R",
"name": {
"family": "Genzel",
"given": "R."
},
"orcid": "0000-0002-2767-9653"
},
{
"id": "Gillessen-S",
"name": {
"family": "Gillessen",
"given": "S."
}
},
{
"id": "Goldwurm-A",
"name": {
"family": "Goldwurm",
"given": "A."
}
},
{
"id": "Habibi-M",
"name": {
"family": "Habibi",
"given": "M."
}
},
{
"id": "Haggard-D",
"name": {
"family": "Haggard",
"given": "D."
},
"orcid": "0000-0001-6803-2138"
},
{
"id": "Hailey-C",
"name": {
"family": "Hailey",
"given": "C."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Merloni-A",
"name": {
"family": "Merloni",
"given": "A."
}
},
{
"id": "Mori-K",
"name": {
"family": "Mori",
"given": "K."
}
},
{
"id": "Nandra-K",
"name": {
"family": "Nandra",
"given": "K."
},
"orcid": "0000-0002-7150-9192"
},
{
"id": "Ott-T",
"name": {
"family": "Ott",
"given": "T."
}
},
{
"id": "Pfuhl-O",
"name": {
"family": "Pfuhl",
"given": "O."
}
},
{
"id": "Plewa-P-M",
"name": {
"family": "Plewa",
"given": "P. M."
}
},
{
"id": "Waisberg-I",
"name": {
"family": "Waisberg",
"given": "I."
}
}
]
},
"title": "A powerful flare from Sgr A* confirms the synchrotron nature of the X-ray emission",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 methods: data analysis \u2013 Galaxy: centre",
"note": "\u00a9 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.\n\nAccepted 2017 March 8. Received 2017 March 8; in original form 2016 October 12. Published: 10 March 2017.\n\nThe authors wish to thank Jan-Uwe Ness, Ignacio de la Calle, Karl Foster and the rest of the XMM\u2013Newton and NuSTAR scheduling teams for the enormous support that made this multiwavelength campaign possible, as well as the referee for the careful reading of the paper. GP thanks Mark R. Morris, Gabriele Ghisellini, Lorenzo Sironi, Hendrik J. van Eerten, Michi Baub\u00f6ck and Francesco Coti-Zelati, for useful discussion. RT and AG acknowledge support from CNES. This research has made use both of data obtained with XMM\u2013Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, and on data obtained from the Chandra Data Archive. The GC XMM\u2013Newton monitoring project is supported by the Bundesministerium f\u00fcr Wirtschaft und Technologie/Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (BMWI/DLR, FKZ 50 OR 1408 and FKZ 50 OR 1604) and the Max Planck Society.\n\nPublished - Ponti_2017p2447.pdf
Submitted - 1703.03410.pdf
",
"abstract": "We present the first fully simultaneous fits to the near-infrared (NIR) and X-ray spectral slope (and its evolution) during a very bright flare from Sgr A*, the supermassive black hole at the Milky Way's centre. Our study arises from ambitious multiwavelength monitoring campaigns with XMM\u2013Newton, NuSTAR and SINFONI. The average multiwavelength spectrum is well reproduced by a broken power law with \u0393_(NIR) = 1.7 \u00b1 0.1 and \u0393_X = 2.27 \u00b1 0.12. The difference in spectral slopes (\u0394\u0393 = 0.57 \u00b1 0.09) strongly supports synchrotron emission with a cooling break. The flare starts first in the NIR with a flat and bright NIR spectrum, while X-ray radiation is detected only after about 10^3 s, when a very steep X-ray spectrum (\u0394\u0393 = 1.8 \u00b1 0.4) is observed. These measurements are consistent with synchrotron emission with a cooling break and they suggest that the high-energy cut-off in the electron distribution (\u03b3_(max)) induces an initial cut-off in the optical\u2013UV band that evolves slowly into the X-ray band. The temporal and spectral evolution observed in all bright X-ray flares are also in line with a slow evolution of \u03b3_(max). We also observe hints for a variation of the cooling break that might be induced by an evolution of the magnetic field (from B \u223c 30 \u00b1 8 G to B \u223c 4.8 \u00b1 1.7 G at the X-ray peak). Such drop of the magnetic field at the flare peak would be expected if the acceleration mechanism is tapping energy from the magnetic field, such as in magnetic reconnection. We conclude that synchrotron emission with a cooling break is a viable process for Sgr A*'s flaring emission.",
"date": "2017-06-21",
"date_type": "published",
"publication": "Monthly Notices of the Royal Astronomical Society",
"volume": "468",
"number": "2",
"publisher": "Royal Astronomical Society",
"pagerange": "2447-2468",
"id_number": "CaltechAUTHORS:20170314-130058938",
"issn": "0035-8711",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170314-130058938",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"funders": {
"items": [
{
"agency": "Centre National d'\u00c9tudes Spatiales (CNES)"
},
{
"agency": "European Space Agency (ESA)"
},
{
"agency": "NASA"
},
{
"agency": "Bundesministerium f\u00fcr Wirtschaft und Technologie (BMWi)",
"grant_number": "FKZ 50 OR 1408"
},
{
"agency": "Bundesministerium f\u00fcr Wirtschaft und Technologie (BMWi)",
"grant_number": "FKZ 50 OR 1604"
},
{
"agency": "Max Planck Society"
}
]
},
"local_group": {
"items": [
{
"id": "NuSTAR"
},
{
"id": "Space-Radiation-Laboratory"
},
{
"id": "Astronomy-Department"
}
]
},
"doi": "10.1093/mnras/stx596",
"primary_object": {
"basename": "1703.03410.pdf",
"url": "https://authors.library.caltech.edu/records/8cbe7-xpk65/files/1703.03410.pdf"
},
"related_objects": [
{
"basename": "Ponti_2017p2447.pdf",
"url": "https://authors.library.caltech.edu/records/8cbe7-xpk65/files/Ponti_2017p2447.pdf"
}
],
"pub_year": "2017",
"author_list": "Ponti, G.; George, E.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/0a850-j0f82",
"eprint_id": 101101,
"eprint_status": "archive",
"datestamp": "2023-08-19 03:37:20",
"lastmod": "2026-04-01 16:49:12",
"type": "monograph",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Webber-W-R",
"name": {
"family": "Webber",
"given": "W. R."
}
},
{
"id": "Stone-E-C",
"name": {
"family": "Stone",
"given": "E. C."
},
"orcid": "0000-0002-2010-5462"
},
{
"id": "Cummings-A-C",
"name": {
"family": "Cummings",
"given": "A. C."
},
"orcid": "0000-0002-3840-7696"
},
{
"id": "Heikkila-B-C",
"name": {
"family": "Heikkila",
"given": "B."
}
},
{
"id": "Lal-Nand",
"name": {
"family": "Lal",
"given": "N."
}
}
]
},
"title": "The Intensities of Cosmic Ray H and He Nuclei at ~250 MeV/nuc Measured by Voyagers 1 and 2 - Using these Intensities to Determine the Solar Modulation Parameter in the Inner Heliosphere and the Heliosheath Over a 40 Year Time Period",
"ispublished": "unpub",
"full_text_status": "public",
"note": "The authors wish to thank JPL for their unfailing support, both moral and financial, for 40 years since the launch of V1 and V2 in August, 1977.\n\nSubmitted - 1706.02772.pdf
",
"abstract": "We have determined the solar modulation potential, \u03a6, vs. time that is observed at Voyager 1 and 2 from measurements of the H and He nuclei intensities at a common energy of 250 MeVnuc. The H nuclei have a rigidity 0.7 GV, the He nuclei 1.4 GV. These measurements cover a 40 year time period, which includes almost 4 cycles of solar 11 year sunspot variations, throughout the inner heliosphere out to the HTS at distances of 95 AU and 85 AU, respectively at V1 and V2, and then beyond in the heliosheath. Inside the HTS the modulation potential vs. time curves at V1 and V2 show a very similar temporal structure to those observed at the Earth. During a later period of maximum solar modulation from 2000.0 to 2005.0 when V1 and V2 are in the outer heliosphere between 60-94 AU, the main temporal features of the modulation potential curves at all 3 locations match up with appropriate time delays at V1 and V2 if it is assumed that spatially coherent structures are moving outward past V1 and V2, with outward speeds of up to 700 Kms\u207b\u00b9. After 2004.0 V1 and V2 are at latitudes of +35\u00b0 and -30\u00b0 respectively, placing lower limits on the latitude extent of these structures. Beyond the HTS in the heliosheath the modulation potential slowly decreases at both spacecraft with only a weak evidence of the unusual modulation minimum observed at the Earth in 2009, for example. A sudden decrease of the modulation potential 50 MV for both H and He nuclei occurs at V1 just before the heliopause crossing at about 122 AU. This decrease has not yet been observed at V2, which is now at 113 AU and still observing a modulation potential 60 MV.",
"date": "2017-06-08",
"date_type": "published",
"publisher": "arXiv",
"id_number": "CaltechAUTHORS:20200204-082135453",
"official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200204-082135453",
"rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.",
"local_group": {
"items": [
{
"id": "Space-Radiation-Laboratory"
}
]
},
"doi": "10.48550/arXiv.1706.02772",
"primary_object": {
"basename": "1706.02772.pdf",
"url": "https://authors.library.caltech.edu/records/0a850-j0f82/files/1706.02772.pdf"
},
"pub_year": "2017",
"author_list": "Webber, W. R.; Stone, E. C.; et al."
},
{
"id": "https://authors.library.caltech.edu/records/nqv24-2sh58",
"eprint_id": 77857,
"eprint_status": "archive",
"datestamp": "2023-08-19 03:33:07",
"lastmod": "2026-04-01 20:12:16",
"type": "article",
"metadata_visibility": "show",
"creators": {
"items": [
{
"id": "Lohfink-A-M",
"name": {
"family": "Lohfink",
"given": "Anne M."
}
},
{
"id": "Fabian-A-C",
"name": {
"family": "Fabian",
"given": "Andrew C."
},
"orcid": "0000-0002-9378-4072"
},
{
"id": "Ballantyne-D-R",
"name": {
"family": "Ballantyne",
"given": "David R."
},
"orcid": "0000-0001-8128-6976"
},
{
"id": "Boggs-S-E",
"name": {
"family": "Boggs",
"given": "S. E."
},
"orcid": "0000-0001-9567-4224"
},
{
"id": "Boorman-P-G",
"name": {
"family": "Boorman",
"given": "Peter"
},
"orcid": "0000-0001-9379-4716"
},
{
"id": "Christensen-F-E",
"name": {
"family": "Christensen",
"given": "F. E."
},
"orcid": "0000-0001-5679-1946"
},
{
"id": "Craig-W-W",
"name": {
"family": "Craig",
"given": "W. W."
}
},
{
"id": "Farrah-D",
"name": {
"family": "Farrah",
"given": "Duncan"
},
"orcid": "0000-0003-1748-2010"
},
{
"id": "Garc\u00eda-Javier-A",
"name": {
"family": "Garc\u00eda",
"given": "Javier"
},
"orcid": "0000-0003-3828-2448"
},
{
"id": "Hailey-C-J",
"name": {
"family": "Hailey",
"given": "C. J."
}
},
{
"id": "Harrison-F-A",
"name": {
"family": "Harrison",
"given": "F. A."
},
"orcid": "0000-0002-4226-8959"
},
{
"id": "Ricci-C",
"name": {
"family": "Ricci",
"given": "Claudio"
},
"orcid": "0000-0001-5231-2645"
},
{
"id": "Stern-D",
"name": {
"family": "Stern",
"given": "Daniel"
},
"orcid": "0000-0003-2686-9241"
},
{
"id": "Zhang-W-W",
"name": {
"family": "Zhang",
"given": "W. W."
},
"orcid": "0000-0002-1426-9698"
}
]
},
"title": "The X-Ray Reflection Spectrum of the Radio-loud Quasar 4C 74.26",
"ispublished": "pub",
"full_text_status": "public",
"keywords": "black hole physics \u2013 galaxies: active \u2013 quasars: individual (4C 74.26) \u2013 quasars: supermassive black holes \u2013 X-rays: individual (4C 74.26)",
"note": "\u00a9 2017 The American Astronomical Society.\n\nReceived 2017 January 2; revised 2017 April 3; accepted 2017 April 10; published 2017 May 26.\n\nThe authors thank the referee for the useful comments that have helped to improve the manuscript. A.L. acknowledges support from the ERC Advanced Grant FEEDBACK 340442 and useful discussions with Niel Brandt. J.A.G. acknowledges partial funding provided by the Alexander von Humboldt Foundation. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This work has made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).\n\nPublished - Lohfink_2017_ApJ_841_80.pdf
Submitted - 1704.03673.pdf
",
"abstract": "The relativistic jets created by some active galactic nuclei are important agents of AGN feedback. In spite of this, our understanding of what produces these jets is still incomplete. X-ray observations, which can probe the processes operating in the central regions in the immediate vicinity of the supermassive black hole, the presumed jet launching point, are potentially particularly valuable in illuminating the jet formation process. Here, we present the hard X-ray NuST ![41586_2023_6064_Fig5_ESM.jpg](\"/records/61ems-vbe67/files/41586_2023_6064_Fig5_ESM.jpg?download=1\"){kind=link}
![41586_2023_6064_Fig6_ESM.jpg](\"/records/61ems-vbe67/files/41586_2023_6064_Fig6_ESM.jpg?download=1\"){kind=link}
![41586_2023_6064_Tab1_ESM.jpg](\"/records/61ems-vbe67/files/41586_2023_6064_Tab1_ESM.jpg?download=1\"){kind=link}
![41586_2023_6064_Tab2_ESM.jpg](\"/records/61ems-vbe67/files/41586_2023_6064_Tab2_ESM.jpg?download=1\"){kind=link}
![41586_2023_5955_Fig5_ESM.jpg](\"/records/kspbf-btw64/files/41586_2023_5955_Fig5_ESM.jpg?download=1\"){kind=link}
![41586_2023_5955_Fig6_ESM.jpg](\"/records/kspbf-btw64/files/41586_2023_5955_Fig6_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Fig3_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Fig3_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Fig4_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Fig4_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Fig5_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Fig5_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Fig6_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Fig6_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Fig7_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Fig7_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Fig8_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Fig8_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Tab1_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Tab1_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Tab2_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Tab2_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Tab3_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Tab3_ESM.jpg?download=1\"){kind=link}
![41586_2022_5476_Tab4_ESM.jpg](\"/records/dqsvz-9ty06/files/41586_2022_5476_Tab4_ESM.jpg?download=1\"){kind=link}
![41550_2021_1594_Fig5_ESM.webp](\"/records/2jepy-bra36/files/41550_2021_1594_Fig5_ESM.webp?download=1\"){kind=link}
![41550_2021_1594_Fig6_ESM.webp](\"/records/2jepy-bra36/files/41550_2021_1594_Fig6_ESM.webp?download=1\"){kind=link}
![41550_2021_1594_Tab1_ESM.webp](\"/records/2jepy-bra36/files/41550_2021_1594_Tab1_ESM.webp?download=1\"){kind=link}
![41550_2021_1594_Tab2_ESM.webp](\"/records/2jepy-bra36/files/41550_2021_1594_Tab2_ESM.webp?download=1\"){kind=link}
![41586_2019_1811_Fig5_ESM.jpg](\"/records/0c97f-h2t19/files/41586_2019_1811_Fig5_ESM.jpg?download=1\"){kind=link}
![41586_2019_1811_Fig6_ESM.jpg](\"/records/0c97f-h2t19/files/41586_2019_1811_Fig6_ESM.jpg?download=1\"){kind=link}