[
{
"id": "authors:6zq6m-a0w28",
"collection": "authors",
"collection_id": "6zq6m-a0w28",
"cite_using_url": "https://authors.library.caltech.edu/records/6zq6m-a0w28",
"type": "article",
"title": "The circumstellar environment of the young, low-mass dipper star JH 223. Accretion and large-scale magnetic field topology",
"author": [
{
"family_name": "Freitas",
"given_name": "T. P.",
"orcid": "0009-0008-9261-7396"
},
{
"family_name": "Bouvier",
"given_name": "J.",
"orcid": "0000-0002-7450-6712"
},
{
"family_name": "Zaire",
"given_name": "B.",
"orcid": "0000-0002-9328-9530"
},
{
"family_name": "Alencar",
"given_name": "S. H. P.",
"orcid": "0000-0002-5171-8376"
},
{
"family_name": "Sousa",
"given_name": "A. P.",
"orcid": "0000-0001-7397-8972"
},
{
"family_name": "Rebull",
"given_name": "L.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Bayo",
"given_name": "A.",
"orcid": "0000-0001-7868-7031"
},
{
"family_name": "Frasca",
"given_name": "A.",
"orcid": "0000-0002-0474-0896"
},
{
"family_name": "Alonso-Santiago",
"given_name": "J.",
"orcid": "0000-0001-9707-3107"
},
{
"family_name": "Grankin",
"given_name": "K.",
"orcid": "0000-0001-5707-8448"
},
{
"family_name": "Contreras Pe\u00f1a",
"given_name": "C.",
"orcid": "0000-0003-1894-1880"
},
{
"family_name": "Cody",
"given_name": "A. M.",
"orcid": "0000-0002-3656-6706"
},
{
"family_name": "Hillenbrand",
"given_name": "L. A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Carmona",
"given_name": "A.",
"orcid": "0000-0003-2471-1299"
}
],
"abstract": "Context. Studies of magnetospheric accretion and magnetic field topology in T Tauri stars have advanced over the years, but their applications to fully convective, very-low-mass T Tauri stars remain relatively unexplored.
\nAims. We aim to analyze the circumstellar environment of the very-low-mass dipper-like star JH 223 by investigating the accretion process and characterizing its large-scale magnetic field topology.
\nMethods. We analyzed the photometric variability of JH 223 using observations from multiple telescopes, including K2, TESS, and LCOGT across different epochs. Additionally, we used Gemini/GRACES spectroscopic and CFHT/SPIRou spectropolarimetric data to investigate the star-disk interaction and to characterize the large-scale stellar magnetic field using Zeeman-Doppler imaging.
\nResults. JH 223 is a fully convective classical T Tauri star with an age of about 3 Myr and a mass of 0.4 M\u2299. The large-scale surface magnetic field is predominantly poloidal, with a 250 G dipolar component. The dipole field strength and the mass accretion rate indicate that the disk gas truncation radius is located near the corotation radius (6\u2005±\u20051 R\u2605). The star-disk interaction, combined with the inclined dipole, generates accretion columns that warp the inner disk. As the star rotates, this warp periodically obscures the stellar surface every 3.31 days, producing the dipper light curves. The same period is also detected in variations of the radial velocity and the longitudinal magnetic field. The accretion columns, traced by strong redshifted absorption components in Hα and He I 1083nm, are associated with the inner disk warp, as they occur around the same rotational phase. The accretion process in JH 223 is dynamic, transitioning from an unstable to a stable regime over a few weeks, consistent with predictions from magnetohydrodynamic simulations of the star-disk interaction.
\nConclusions. Results from multi-technique observations suggest that the magnetospheric accretion model remains valid for fully convective very-low-mass young stars.
",
"doi": "10.1051/0004-6361/202558514",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy & Astrophysics",
"publication_date": "2026-05",
"volume": "709",
"pages": "A243"
},
{
"id": "authors:5qtdn-t6t93",
"collection": "authors",
"collection_id": "5qtdn-t6t93",
"cite_using_url": "https://authors.library.caltech.edu/records/5qtdn-t6t93",
"type": "article",
"title": "A young progenitor for the most common planetary systems in the Galaxy",
"author": [
{
"family_name": "Livingston",
"given_name": "John H.",
"orcid": "0000-0002-4881-3620"
},
{
"family_name": "Petigura",
"given_name": "Erik A.",
"orcid": "0000-0003-0967-2893"
},
{
"family_name": "David",
"given_name": "Trevor J."
},
{
"family_name": "Masuda",
"given_name": "Kento"
},
{
"family_name": "Owen",
"given_name": "James",
"orcid": "0000-0002-4856-7837"
},
{
"family_name": "Nesvorn\u00fd",
"given_name": "David",
"orcid": "0000-0002-4547-4301"
},
{
"family_name": "Batygin",
"given_name": "Konstantin",
"orcid": "0000-0002-7094-7908",
"clpid": "Batygin-K"
},
{
"family_name": "de Leon",
"given_name": "Jerome"
},
{
"family_name": "Mori",
"given_name": "Mayuko",
"orcid": "0000-0003-1368-6593"
},
{
"family_name": "Ikuta",
"given_name": "Kai"
},
{
"family_name": "Fukui",
"given_name": "Akihiko",
"orcid": "0000-0002-4909-5763"
},
{
"family_name": "Watanabe",
"given_name": "Noriharu"
},
{
"family_name": "Orell Miquel",
"given_name": "Jaume",
"orcid": "0000-0003-2066-8959"
},
{
"family_name": "Murgas",
"given_name": "Felipe",
"orcid": "0000-0001-9087-1245"
},
{
"family_name": "Parviainen",
"given_name": "Hannu",
"orcid": "0000-0001-5519-1391"
},
{
"family_name": "Korth",
"given_name": "Judith",
"orcid": "0000-0002-0076-6239"
},
{
"family_name": "Libotte",
"given_name": "Florence"
},
{
"family_name": "Abreu Garc\u00eda",
"given_name": "N\u00e9stor",
"orcid": "0009-0002-5067-5463"
},
{
"family_name": "Gallardo",
"given_name": "Pedro Pablo Meni",
"orcid": "0009-0001-7943-0075"
},
{
"family_name": "Narita",
"given_name": "Norio",
"orcid": "0000-0001-8511-2981"
},
{
"family_name": "Pall\u00e9",
"given_name": "Enric",
"orcid": "0000-0003-0987-1593"
},
{
"family_name": "Tamura",
"given_name": "Motohide",
"orcid": "0000-0002-6510-0681"
},
{
"family_name": "Yonehara",
"given_name": "Atsunori"
},
{
"family_name": "Ridden-Harper",
"given_name": "Andrew"
},
{
"family_name": "Bieryla",
"given_name": "Allyson",
"orcid": "0000-0001-6637-5401"
},
{
"family_name": "Trani",
"given_name": "Alessandro A."
},
{
"family_name": "Mamajek",
"given_name": "Eric E.",
"orcid": "0000-0003-2008-1488",
"clpid": "Mamajek-Eric-E"
},
{
"family_name": "Ciardi",
"given_name": "David R.",
"orcid": "0000-0002-5741-3047",
"clpid": "Ciardi-David-R"
},
{
"family_name": "Gorjian",
"given_name": "Varoujan",
"orcid": "0000-0002-8990-2101",
"clpid": "Gorjian-Varoujan"
},
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Newton",
"given_name": "Elisabeth R."
},
{
"family_name": "Mann",
"given_name": "Andrew W.",
"orcid": "0000-0003-3654-1602"
},
{
"family_name": "Vanderburg",
"given_name": "Andrew",
"orcid": "0000-0001-7246-5438"
},
{
"family_name": "Stef\u00e1nsson",
"given_name": "Gu\u00f0mundur"
},
{
"family_name": "Mahadevan",
"given_name": "Suvrath",
"orcid": "0000-0001-9596-7983"
},
{
"family_name": "Ca\u00f1as",
"given_name": "Caleb"
},
{
"family_name": "Ninan",
"given_name": "Joe"
},
{
"family_name": "Higuera",
"given_name": "Jesus",
"orcid": "0000-0002-3985-8528"
},
{
"family_name": "Todorov",
"given_name": "Kamen",
"orcid": "0000-0002-9276-8118"
},
{
"family_name": "D\u00e9sert",
"given_name": "Jean-Michel",
"orcid": "0000-0002-0875-8401"
},
{
"family_name": "Pino",
"given_name": "Lorenzo",
"orcid": "0000-0002-1321-8856"
}
],
"abstract": "The Galaxy's most common known planetary systems have several Earth-to-Neptune-size planets in compact orbits. At small orbital separations, larger planets are less common than their smaller counterparts by an order of magnitude. The young star V1298 Tau hosts one such compact planetary system, albeit with four planets that are uncommonly large (5 to 10 Earth radii). The planets form a chain of near-resonances that result in transit-timing variations of several hours. Here we present a multi-year campaign to characterize this system with transit-timing variations, a method insensitive to the intense magnetic activity of the star. Through targeted observations, we first resolved the previously unknown orbital period of the outermost planet. The full 9-year baseline from these and archival data then enabled robust determination of the masses and orbital parameters for all four planets. We find the planets have low, sub-Neptune masses and nearly circular orbits, implying a dynamically tranquil history. Their low masses and large radii indicate that the inner planets underwent a period of rapid cooling immediately after dispersal of the protoplanetary disk. Still, they are much less dense than mature planets of comparable size. We predict the planets will contract to 1.5–4.0 Earth radii and join the population of super-Earths and sub-Neptunes that nature produces in abundance.
",
"doi": "10.1038/s41586-025-09840-z",
"pmcid": "PMC12779570",
"issn": "0028-0836",
"publisher": "Nature Publishing Group",
"publication": "Nature",
"publication_date": "2026-01-08",
"series_number": "8096",
"volume": "649",
"issue": "8096",
"pages": "310-314"
},
{
"id": "authors:vhxs4-9vh92",
"collection": "authors",
"collection_id": "vhxs4-9vh92",
"cite_using_url": "https://authors.library.caltech.edu/records/vhxs4-9vh92",
"type": "article",
"title": "Circumstellar Disk Accretion Across the Lagoon Nebula: The Influence of Environment and Stellar Mass",
"author": [
{
"family_name": "Venuti",
"given_name": "Laura",
"orcid": "0000-0002-4115-0318",
"clpid": "Venuti-Laura"
},
{
"family_name": "Cody",
"given_name": "Ann Marie",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Beccari",
"given_name": "Giacomo",
"orcid": "0000-0002-3865-9906",
"clpid": "Beccari-Giacomo"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Irwin",
"given_name": "Michael J.",
"orcid": "0000-0002-2191-9038",
"clpid": "Irwin-Michael-J"
},
{
"family_name": "Thanvantri",
"given_name": "Apoorva",
"clpid": "Thanvantri-Apoorva"
},
{
"family_name": "Thanvantri",
"given_name": "Sowmya",
"orcid": "0009-0005-8540-0963",
"clpid": "Thanvantri-Sowmya"
},
{
"family_name": "Alencar",
"given_name": "Silvia H. P.",
"orcid": "0000-0002-5171-8376",
"clpid": "Alencar-Silvia-H-P"
},
{
"family_name": "Leal",
"given_name": "Clara O.",
"clpid": "Leal-Clara-O"
},
{
"family_name": "Barentsen",
"given_name": "Geert",
"orcid": "0000-0002-3306-3484",
"clpid": "Barentsen-Geert"
},
{
"family_name": "Drew",
"given_name": "Janet E.",
"orcid": "0000-0003-1192-7082",
"clpid": "Drew-Janet-E"
},
{
"family_name": "Howell",
"given_name": "Steve B.",
"orcid": "0000-0002-2532-2853",
"clpid": "Howell-Steve-B"
}
],
"abstract": "\n
Pre-main-sequence disk accretion is pivotal for determining the final stellar properties and the early conditions for close-in planets. We aim to establish the impact of internal (stellar mass) and external (radiation field) parameters on the disk evolution in the Lagoon Nebula massive star-forming region. We employ simultaneous u, g, r, i, Hα time-series photometry, archival infrared data, and high-precision K2 light curves to derive the stellar, disk, and accretion properties for 1012 Lagoon Nebula members. We estimate that of all young stars in the Lagoon Nebula, 34%–37% have inner disks traceable down to ∼12 μm, while 38%–41% are actively accreting. We detect disks ∼1.5 times more frequently around G, K, and M stars than around higher-mass stars, which appear to deplete their inner disks on shorter timescales. We find tentative evidence for a faster disk evolution in the central regions of the Lagoon Nebula, where the bulk of the O/B population is located. Conversely, disks appear to last longer at the nebula outskirts, where the measured fraction of disk-bearing stars tends to exceed that of accreting and disk-free stars. The derived mass accretion rates show a nonuniform dependence on stellar mass between ∼0.2 and 5 M\u2299. In addition, the typical accretion rates appear to differ across the Lagoon Nebula extension, with values twice lower in the core region than at its periphery. Finally, we detect tentative radial density gradients in the surface accretion shocks, leading to lags in the appearance of light curve brightness features as a function of wavelength that can amount to ∼7%–30% of the rotation period.
\n
Teachers bring telescope data \"down to Earth\" to provide students with real-world science experiences.
",
"doi": "10.1063/pt.vlhh.iudp",
"issn": "0031-9228",
"publisher": "AIP Publishing",
"publication": "Physics Today",
"publication_date": "2024-02",
"series_number": "2",
"volume": "77",
"issue": "2",
"pages": "44-50"
},
{
"id": "authors:t2hch-kam83",
"collection": "authors",
"collection_id": "t2hch-kam83",
"cite_using_url": "https://authors.library.caltech.edu/records/t2hch-kam83",
"type": "article",
"title": "Transient Corotating Clumps around Adolescent Low-mass Stars from Four Years of TESS",
"author": [
{
"family_name": "Bouma",
"given_name": "Luke G.",
"orcid": "0000-0002-0514-5538",
"clpid": "Bouma-Luke-G"
},
{
"family_name": "Jayaraman",
"given_name": "Rahul",
"orcid": "0000-0002-7778-3117"
},
{
"family_name": "Rappaport",
"given_name": "Saul",
"orcid": "0000-0003-3182-5569"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Winn",
"given_name": "Joshua N.",
"orcid": "0000-0002-4265-047X"
},
{
"family_name": "David-Uraz",
"given_name": "Alexandre",
"orcid": "0000-0003-4062-0776"
},
{
"family_name": "Bakos",
"given_name": "G\u00e1sp\u00e1r \u00c1.",
"orcid": "0000-0001-7204-6727"
}
],
"abstract": "\n
Complex periodic variables (CPVs) are stars that exhibit highly structured and periodic optical light curves. Previous studies have indicated that these stars are typically disk-free pre-main-sequence M dwarfs with rotation periods ranging from 0.2 to 2 days. To advance our understanding of these enigmatic objects, we conducted a blind search using TESS 2 minute data of 65,760 K and M dwarfs with T<16 mag and d<150 pc. We found 50 high-quality CPVs, and subsequently determined that most are members of stellar associations. Among the new discoveries are the brightest (T ≈ 9.5 mag), closest (d ≈ 20 pc), and oldest (≈200 Myr) CPVs known. One exceptional object, LP 12-502, exhibited up to eight flux dips per cycle. Some of these dips coexisted with slightly different periods, and the shortest-duration dips precisely matched the expected timescale for transiting small bodies at the corotation radius. Broadly, our search confirms that CPVs are mostly young (\u2272150 Myr) and low-mass (\u22720.4 M\u2299). The flux dips characteristic of the class have lifetimes of ≈100 cycles, although stellar flares seem to induce a sudden dip collapse once every few months. The most plausible explanation for these phenomena remains corotating concentrations of gas or dust. The gas or dust is probably entrained by the star's magnetic field, and the sharp features could result from a multipolar field topology, a hypothesis supported by correspondences between the light curves of CPVs and of rapidly rotating B stars known to have multipolar magnetic fields.
\n
The NASA K2 mission obtained high-precision time-series photometry for four young clusters, including the near-twin 600\u2013800 Myr old Praesepe and Hyades clusters. Hot sub-Neptunes are highly prone to mass-loss mechanisms, given their proximity to the host star and the weakly bound gaseous envelopes, and analyzing this population at young ages can provide strong constraints on planetary evolution models. Using our automated transit detection pipeline, we recover 15 planet candidates across the two clusters, including 10 previously confirmed planets. We find a hot sub-Neptune occurrence rate of 79%\u2013107% for GKM stars in the Praesepe cluster. This is 2.5\u20133.5\u03c3 higher than the occurrence rate of 16.54_(\u2212 0.98)^(+1.00) % for the same planets orbiting the \u223c3\u20139 Gyr old GKM field stars observed by K2, even after accounting for the slightly supersolar metallicity ([Fe/H] \u223c 0.2 dex) of the Praesepe cluster. We examine the effect of adding \u223c100 targets from the Hyades cluster and extending the planet parameter space under examination, and we find similarly high occurrence rates in both cases. The high occurrence rate of young, hot sub-Neptunes could indicate either that these planets are undergoing atmospheric evolution as they age, or that planetary systems that formed when the Galaxy was much younger are substantially different than from today. Under the assumption of the atmospheric mass-loss scenario, a significantly higher occurrence rate of these planets at the intermediate ages of Praesepe and Hyades appears more consistent with the core-powered mass-loss scenario for the origin of the planet radius valley, compared to the photoevaporation scenario.
",
"doi": "10.3847/1538-3881/acf9f9",
"issn": "0004-6256",
"publisher": "American Astronomical Society",
"publication": "The Astronomical Journal",
"publication_date": "2023-12",
"series_number": "6",
"volume": "166",
"issue": "6",
"pages": "248"
},
{
"id": "authors:kz68h-kj450",
"collection": "authors",
"collection_id": "kz68h-kj450",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230705-470712800.1",
"type": "article",
"title": "Stable accretion and episodic outflows in the young transition disk system GM Aurigae. A semester-long optical and near-infrared spectrophotometric monitoring campaign",
"author": [
{
"family_name": "Bouvier",
"given_name": "J.",
"orcid": "0000-0002-7450-6712",
"clpid": "Bouvier-J\u00e8r\u00f4me"
},
{
"family_name": "Sousa",
"given_name": "A. P.",
"orcid": "0000-0001-7397-8972",
"clpid": "Sousa-Alana-P"
},
{
"family_name": "Pouilly",
"given_name": "K.",
"orcid": "0000-0002-9628-2959",
"clpid": "Pouilly-Kim"
},
{
"family_name": "Almenara",
"given_name": "J. M.",
"orcid": "0000-0003-3208-9815",
"clpid": "Almenara-Jose-Manuel"
},
{
"family_name": "Donati",
"given_name": "J.-F.",
"orcid": "0000-0001-5541-2887",
"clpid": "Donati-Jean-Fran\u00e7ois"
},
{
"family_name": "Alencar",
"given_name": "S. H. P.",
"orcid": "0000-0002-5171-8376",
"clpid": "Alencar-Silvia-H-P"
},
{
"family_name": "Frasca",
"given_name": "A.",
"orcid": "0000-0002-0474-0896",
"clpid": "Frasca-Antonio"
},
{
"family_name": "Grankin",
"given_name": "K.",
"orcid": "0000-0001-5707-8448",
"clpid": "Grankin-Konstantin"
},
{
"family_name": "Carmona",
"given_name": "A.",
"orcid": "0000-0003-2471-1299",
"clpid": "Carmona-Andr\u00e9s"
},
{
"family_name": "Pantolmos",
"given_name": "G.",
"orcid": "0000-0001-7788-3727",
"clpid": "Pantolmos-George"
},
{
"family_name": "Zaire",
"given_name": "B.",
"orcid": "0000-0002-9328-9530",
"clpid": "Zaire-Bonnie"
},
{
"family_name": "Bonfils",
"given_name": "X.",
"orcid": "0000-0001-9003-8894",
"clpid": "Bonfils-Xavier"
},
{
"family_name": "Bayo",
"given_name": "A.",
"orcid": "0000-0001-7868-7031",
"clpid": "Bayo-Amelia"
},
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Alonso-Santiago",
"given_name": "J.",
"orcid": "0000-0001-9707-3107",
"clpid": "Alonso-Santiago-Javier"
},
{
"family_name": "Gameiro",
"given_name": "J. F.",
"orcid": "0000-0002-1970-7001",
"clpid": "Gameiro-Jorge-Filipe"
},
{
"family_name": "Cook",
"given_name": "N. J.",
"orcid": "0000-0003-4166-4121",
"clpid": "Cook-Neil-J"
},
{
"family_name": "Artigau",
"given_name": "E.",
"orcid": "0000-0003-3506-5667",
"clpid": "Artigau-\u00c9tienne"
}
],
"abstract": "Context.Young stellar systems actively accrete from their circumstellar disk and simultaneously launch outflows. The physical link between accretion and ejection processes remains to be fully understood. \n\nAims. We investigate the structure and dynamics of magnetospheric accretion and associated outflows on a scale smaller than 0.1 au around the young transitional disk system GM Aur. \n\nMethods. We devised a coordinated observing campaign to monitor the variability of the system on timescales ranging from days to months, including partly simultaneous high-resolution optical and near-infrared spectroscopy, multiwavelength photometry, and low-resolution near-infrared spectroscopy, over a total duration of six months, covering 30 rotational cycles. We analyzed the photometric and line profile variability to characterize the accretion and ejection processes. \n\nResults. The optical and near-infrared light curves indicate that the luminosity of the system is modulated by surface spots at the stellar rotation period of 6.04 \u00b1 0.15 days. Part of the Balmer, Paschen, and Brackett hydrogen line profiles as well as the HeI 5876 \u00c5 and HeI 10830 \u00c5 line profiles are modulated on the same period. The Pa\u03b2 line flux correlates with the photometric excess in the u' band, which suggests that most of the line emission originates from the accretion process. High-velocity redshifted absorptions reaching below the continuum periodically appear in the near-infrared line profiles at the rotational phase in which the veiling and line fluxes are the largest. These are signatures of a stable accretion funnel flow and associated accretion shock at the stellar surface. This large-scale magnetospheric accretion structure appears fairly stable over at least 15 and possibly up to 30 rotational periods. In contrast, outflow signatures randomly appear as blueshifted absorption components in the Balmer and HeI 10830 \u00c5 line profiles. They are not rotationally modulated and disappear on a timescale of a few days. The coexistence of a stable, large-scale accretion pattern and episodic outflows supports magnetospheric ejections as the main process occurring at the star-disk interface. \n\nConclusions. Long-term monitoring of the variability of the GM Aur transitional disk system provides clues to the accretion and ejection structure and dynamics close to the star. Stable magnetospheric accretion and episodic outflows appear to be physically linked on a scale of a few stellar radii in this system.",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy and Astrophysics",
"publication_date": "2023-04",
"volume": "672",
"pages": "Art. No. A5"
},
{
"id": "authors:j4t8q-0pn54",
"collection": "authors",
"collection_id": "j4t8q-0pn54",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230328-706203600.28",
"type": "article",
"title": "New insights on the near-infrared veiling of young stars using CFHT/SPIRou data",
"author": [
{
"family_name": "Sousa",
"given_name": "A. P.",
"orcid": "0000-0001-7397-8972",
"clpid": "Sousa-Alana-P"
},
{
"family_name": "Bouvier",
"given_name": "J.",
"orcid": "0000-0002-7450-6712",
"clpid": "Bouvier-J\u00e8r\u00f4me"
},
{
"family_name": "Alencar",
"given_name": "S. H. P.",
"orcid": "0000-0002-5171-8376",
"clpid": "Alencar-Silvia-H-P"
},
{
"family_name": "Donati",
"given_name": "J.-F.",
"orcid": "0000-0001-5541-2887",
"clpid": "Donati-Jean-Fran\u00e7ois"
},
{
"family_name": "Dougados",
"given_name": "C.",
"orcid": "0000-0001-6660-936X",
"clpid": "Dougados-Catherine"
},
{
"family_name": "Alecian",
"given_name": "E.",
"orcid": "0000-0001-5260-7179",
"clpid": "Alecian-Evelyne"
},
{
"family_name": "Carmona",
"given_name": "A.",
"orcid": "0000-0003-2471-1299",
"clpid": "Carmona-Andr\u00e9s"
},
{
"family_name": "Rebull",
"given_name": "L.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Cook",
"given_name": "N.",
"orcid": "0000-0003-4166-4121",
"clpid": "Cook-Neil-J"
},
{
"family_name": "Artigau",
"given_name": "\u00c9.",
"orcid": "0000-0003-3506-5667",
"clpid": "Artigau-\u00c9tienne"
},
{
"family_name": "Fouqu\u00e9",
"given_name": "P.",
"orcid": "0000-0002-1436-7351",
"clpid": "Fouqu\u00e9-Pascal"
},
{
"family_name": "Doyon",
"given_name": "R.",
"orcid": "0000-0001-5485-4675",
"clpid": "Doyon-Ren\u00e9"
},
{
"literal": "SLS consortium"
}
],
"abstract": "Context. Veiling is ubiquitous at different wavelength ranges in classical T Tauri stars. However, the origin of the veiling in the infrared (IR) domain is not well understood at present. The accretion spot alone is not enough to explain the shallow photospheric IR lines in accreting systems, suggesting that another source is contributing to the veiling in the near-infrared (NIR). The inner disk is often quoted as the additional emitting source meant to explain the IR veiling. \n\nAims. In this work, we aim to measure and discuss the NIR veiling to understand its origins and variability timescale. \n\nMethods. We used a sample of 14 accreting stars observed with the CFHT/SPIRou spectrograph, within the framework of the SPIRou Legacy Survey, to measure the NIR veiling along the YJHK bands. We compared the veiling measurements with accretion and inner disk diagnostics. We also analyzed circumstellar emission lines and photometric observations from the literature. \n\nResults. The measured veiling grows from the Y to the K band for most of the targets in our sample. The IR veiling agrees with NIR emission excess obtained using photometric data. However, we also find a linear correlation between the veiling and the accretion properties of the system, showing that accretion contributes to the inner disk heating and, consequently, to the inner disk emission excess. We also show a connection between the NIR veiling and the system's inclination with respect to our line of sight. This is probably due to the reduction of the visible part of the inner disk edge, where the NIR emission excess is expected to arise, as the inclination of the system increases. Our search for periods on the veiling variability showed that the IR veiling is not clearly periodic in the typical timescale of stellar rotation \u2013 which, again, is broadly consistent with the idea that the veiling comes from the inner disk region. The NIR veiling appears variable on a timescale of a day, showing the night-by-night dynamics of the optical veiling variability. In the long term, the mean NIR veiling seems to be stable for most of the targets on timescales of a month to a few years. However, during occasional episodes of high accretion in classical T Tauri stars, which affect the system's dynamic, the veiling also seems to be much more prominent at such times, as we found in the case of the target RU Lup. \n\nConclusions. We provide further evidence that for most targets in our sample, the veiling that mainly occurs in the JHK bands arises from dust in the inner disk.",
"doi": "10.1051/0004-6361/202244720",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy and Astrophysics",
"publication_date": "2023-02",
"volume": "670",
"pages": "Art. No. A142"
},
{
"id": "authors:qep4w-ja271",
"collection": "authors",
"collection_id": "qep4w-ja271",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220804-765250000",
"type": "article",
"title": "Rotation of Low-mass Stars in Upper Centaurus\u2013Lupus and Lower Centaurus\u2013Crux with TESS",
"author": [
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Stauffer",
"given_name": "J. R.",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Hillenbrand",
"given_name": "L. A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Cody",
"given_name": "A. M.",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Kruse",
"given_name": "Ethan",
"orcid": "0000-0002-0493-1342",
"clpid": "Kruse-Ethan"
},
{
"family_name": "Powell",
"given_name": "Brian P.",
"orcid": "0000-0003-0501-2636",
"clpid": "Powell-Brian-P"
}
],
"abstract": "We present stellar rotation rates derived from Transiting Exoplanet Survey Satellite (TESS) light curves for stars in Upper Centaurus\u2013Lupus (UCL; \u223c136 pc, \u223c16 Myr) and Lower Centaurus\u2013Crux (LCC; \u223c115 pc, \u223c17 Myr). We find spot-modulated periods (P) for \u223c90% of members. The range of light-curve and periodogram shapes echoes that found for other clusters with K2, but fewer multiperiod stars may be an indication of the different noise characteristics of TESS, or a result of the source selection methods here. The distribution of P as a function of color as a proxy for mass fits nicely in between that for both older and younger clusters observed by K2, with fast rotators being found among both the highest and lowest masses probed here, and a well-organized distribution of M-star rotation rates. About 13% of the stars have an infrared excess, suggesting a circumstellar disk; this is well matched to expectations, given the age of the stars. There is an obvious pileup of disked M stars at P \u223c 2 days, and the pileup may move to shorter P as the mass decreases. There is also a strong concentration of disk-free M stars at P \u223c 2 days, hinting that perhaps these stars have recently freed themselves from their disks. Exploring the rotation rates of stars in UCL/LCC has the potential to help us understand the beginning of the end of the influence of disks on rotation, and the timescale on which stars respond to unlocking.",
"doi": "10.3847/1538-3881/ac75f1",
"issn": "0004-6256",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2022-09",
"series_number": "3",
"volume": "164",
"issue": "3",
"pages": "Art. No. 80"
},
{
"id": "authors:fax0g-exj94",
"collection": "authors",
"collection_id": "fax0g-exj94",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220512-561465000",
"type": "article",
"title": "A Zwicky Transient Facility Look at Optical Variability of Young Stellar Objects in the North America and Pelican Nebulae Complex",
"author": [
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Kiker",
"given_name": "Thaddaeus J.",
"orcid": "0000-0002-2363-2487",
"clpid": "Kiker-Thaddaeus-J"
},
{
"family_name": "Gee",
"given_name": "Miles",
"clpid": "Gee-Miles"
},
{
"family_name": "Lester",
"given_name": "Owen",
"clpid": "Lester-Owen"
},
{
"family_name": "Braunfeld",
"given_name": "Noah L.",
"clpid": "Braunfeld-Noah-L"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Kuhn",
"given_name": "Michael A.",
"orcid": "0000-0002-0631-7514",
"clpid": "Kuhn-Michael-A"
}
],
"abstract": "We present a study of 323 photometrically variable young stellar objects that are likely members of the North America and Pelican nebulae star-forming region. To do so, we utilize over two years of data in the g and r photometric bands from the Zwicky Transient Facility. We first investigate periodic variability, finding 46 objects (\u223c15% of the sample) with significant periods that phase well and can be attributed to stellar rotation. We then use the quasiperiodicity (Q) and flux asymmetry (M) variability metrics to assign morphological classifications to the remaining aperiodic light curves. Another \u223c39% of the variable star sample beyond the periodic (low Q) sources are also flux-symmetric, but with a quasiperiodic (moderate Q) or stochastic (high Q) nature. Concerning flux-asymmetric sources, our analysis reveals \u223c14% bursters (high negative M) and \u223c29% dippers (high positive M). We also investigate the relationship between variability slopes in the g versus g \u2212 r color\u2013magnitude diagram, and the light-curve morphological classes. Burster-type objects have shallow slopes, while dipper-type variables tend to have higher slopes that are consistent with extinction-driven variability. Our work is one of the earliest applications of the Q and M metrics to ground-based data. We therefore contrast the Q values of high-cadence and high-precision space-based data, for which these metrics were designed, with Q determinations resulting from degraded space-based light curves that have the cadence and photometric precision characteristic of ground-based data.",
"doi": "10.3847/1538-3881/ac62d8",
"issn": "0004-6256",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2022-06",
"series_number": "6",
"volume": "163",
"issue": "6",
"pages": "Art. No. 263"
},
{
"id": "authors:d5a0g-ykq23",
"collection": "authors",
"collection_id": "d5a0g-ykq23",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220816-183020507",
"type": "monograph",
"title": "Rotation of Low-Mass Stars in Upper Centaurus Lupus and Lower Centaurus Crux with TESS",
"author": [
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Stauffer",
"given_name": "J. R.",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Hillenbrand",
"given_name": "L. A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Cody",
"given_name": "A. M.",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Kruse",
"given_name": "Ethan",
"orcid": "0000-0002-0493-1342",
"clpid": "Kruse-Ethan"
},
{
"family_name": "Powell",
"given_name": "Brian P.",
"orcid": "0000-0003-0501-2636",
"clpid": "Powell-Brian-P"
}
],
"abstract": "We present stellar rotation rates derived from Transiting Exoplanet Survey Satellite (TESS) light curves for stars in Upper Centaurus-Lupus (UCL; ~136 pc, ~16 Myr) and Lower Centaurus-Crux (LCC; ~115 pc, ~17 Myr). We find spot-modulated periods (P) for ~90% of members. The range of light curve and periodogram shapes echoes that found for other clusters with K2, but fewer multi-period stars may be an indication of different noise characteristics of TESS, or a result of the source selection methods here. The distribution of P as a function of color as a proxy for mass fits nicely in between that for both older and younger clusters observed by K2, with fast rotators found among both the highest and lowest masses probed here, and a well-organized distribution of M star rotation rates. About 13% of the stars have an infrared (IR) excess, suggesting a circumstellar disk; this is well-matched to expectations, given the age of the stars. There is an obvious pile-up of disked M stars at P~2 days, and the pile-up may move to shorter P as the mass decreases. There is also a strong concentration of disk-free M stars at P~2 days, hinting that perhaps these stars have recently freed themselves from their disks. Exploring the rotation rates of stars in UCL/LCC has the potential to help us understand the beginning of the end of the influence of disks on rotation, and the timescale on which the star responds to unlocking.",
"doi": "10.48550/arXiv.2205.13083",
"publisher": "arXiv",
"publication_date": "2022-05-25"
},
{
"id": "authors:zrarn-zk906",
"collection": "authors",
"collection_id": "zrarn-zk906",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220414-26561000",
"type": "article",
"title": "The Many-faceted Light Curves of Young Disk-bearing Stars in Taurus as Seen by K2",
"author": [
{
"family_name": "Cody",
"given_name": "Ann Marie",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
}
],
"abstract": "We present a comprehensive study of the variability properties of young disk-bearing stars in the Taurus star-forming region, paralleling our previous investigation in \u03c1 Oph and Upper Sco. A sample of 99 confirmed Taurus association members is placed in the diagnostic Q \u2212 M plane of flux asymmetry (M) and (Q), which guides our assignment of variability classes. We find a similar proportion of flux-symmetric variables in Taurus, but more bursters and fewer dippers relative to Upper Sco. The regions also differ in that the amplitudes for periodic and sources are larger in Taurus relative to the more evolved Upper Sco star/disk systems. The relationship between photometric variability patterns at optical wavelengths, which arise in the inner disk and at the stellar surface, are assessed relative to available disk inclination measurements.",
"doi": "10.3847/1538-3881/ac5b73",
"issn": "0004-6256",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2022-05",
"series_number": "5",
"volume": "163",
"issue": "5",
"pages": "Art. No. 212"
},
{
"id": "authors:7dh9j-qvg87",
"collection": "authors",
"collection_id": "7dh9j-qvg87",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220428-212246323",
"type": "article",
"title": "Spitzer Publication Statistics",
"author": [
{
"family_name": "Scire",
"given_name": "E.",
"orcid": "0000-0003-1468-5357",
"clpid": "Scire-Elena"
},
{
"family_name": "Rebull",
"given_name": "Luisa",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Laine",
"given_name": "Seppo",
"orcid": "0000-0003-1250-8314",
"clpid": "Laine-Seppo-J"
}
],
"abstract": "We present statistics on the number of refereed astronomy journal articles that used data from NASA's Spitzer Space Telescope through the end of the calendar year 2020. We discuss the various types of science programs and science categories that were used to collect data during the mission and discuss how operational changes brought on by the depletion of cryogen in 2009 May, including the resulting budget cuts, impacted the publication rate. The post-cryogenic (warm) mission produced fewer papers than the cryogenic mission, but the percentage of the exposure time published did not appreciably change between the warm and cryogenic missions. This was mostly because in the warm mission the length of observations increased, so that each warm paper on average uses more data than the cryogenic papers. We also discuss the speed of publication, archival usage, and the tremendous efficacy of the Legacy and Exploration Science programs (large, coherent investigations), including the value of having well-advertised enhanced data products hosted in centralized archives. We also identify the observations that have been published the largest number of times, and sort them by a variety of metrics (including program type, instrument used, and observation length). Data that have the highest reuse rates in publications were taken early in the Spitzer mission, or belong to one of the large surveys (large either in number of objects, in number of hours observed, or in area covered on the sky). We also assess how often authors have cited the Spitzer fundamental papers or have correctly referenced the Spitzer data they used, finding that as many as 40% of papers have failed to cite the papers, and 15% have made it impossible to identify the data they used.",
"doi": "10.1088/1538-3873/ac4959",
"issn": "1538-3873",
"publisher": "Astronomical Society of the Pacific",
"publication": "Publications of the Astronomical Society of the Pacific",
"publication_date": "2022-05",
"series_number": "1035",
"volume": "134",
"issue": "1035",
"pages": "Art. No. 055001"
},
{
"id": "authors:sbwhn-7d873",
"collection": "authors",
"collection_id": "sbwhn-7d873",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211217-233237912",
"type": "article",
"title": "Best Practices for Data Publication in the Astronomical Literature",
"author": [
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-Xi"
},
{
"family_name": "Schmitz",
"given_name": "Marion",
"orcid": "0000-0002-2055-7549",
"clpid": "Schmitz-Marion"
},
{
"family_name": "Mazzarella",
"given_name": "Joseph M.",
"orcid": "0000-0002-8204-8619",
"clpid": "Mazzarella-Joseph-M"
},
{
"family_name": "Wu",
"given_name": "Xiuqin",
"orcid": "0000-0002-4788-9236",
"clpid": "Wu-Xiuqin"
},
{
"family_name": "van Eyken",
"given_name": "Julian C.",
"orcid": "0000-0003-2192-5371",
"clpid": "van-Eyken-Julian-C"
},
{
"family_name": "Accomazzi",
"given_name": "Alberto",
"orcid": "0000-0002-4110-3511"
},
{
"family_name": "Akeson",
"given_name": "Rachel L.",
"orcid": "0000-0001-9674-1564",
"clpid": "Akeson-Rachel-L"
},
{
"family_name": "Allen",
"given_name": "Mark",
"orcid": "0000-0003-2168-0087",
"clpid": "Allen-Mark-G"
},
{
"family_name": "Beaton",
"given_name": "Rachael",
"orcid": "0000-0002-1691-8217"
},
{
"family_name": "Berriman",
"given_name": "G. Bruce",
"orcid": "0000-0001-8388-534X",
"clpid": "Berriman-G-Bruce"
},
{
"family_name": "Boyle",
"given_name": "Andrew W.",
"orcid": "0000-0001-6037-2971",
"clpid": "Boyle-Andrew-W"
},
{
"family_name": "Brouty",
"given_name": "Marianne",
"orcid": "0000-0002-0944-1211"
},
{
"family_name": "Chan",
"given_name": "Ben H. P.",
"clpid": "Chan-Ben-Hiu-Pan"
},
{
"family_name": "Christiansen",
"given_name": "Jessie L.",
"orcid": "0000-0002-8035-4778",
"clpid": "Christiansen-Jessie-L"
},
{
"family_name": "Ciardi",
"given_name": "David R.",
"orcid": "0000-0002-5741-3047",
"clpid": "Ciardi-David-R"
},
{
"family_name": "Cook",
"given_name": "David",
"orcid": "0000-0002-6877-7655",
"clpid": "Cook-David-O"
},
{
"family_name": "D'Abrusco",
"given_name": "Raffaele",
"orcid": "0000-0003-3073-0605"
},
{
"family_name": "Ebert",
"given_name": "Rick",
"orcid": "0000-0002-9500-8587",
"clpid": "Ebert-Rick"
},
{
"family_name": "Frayer",
"given_name": "Cren",
"clpid": "Frayer-Cren"
},
{
"family_name": "Fulton",
"given_name": "Benjamin J.",
"orcid": "0000-0003-3504-5316",
"clpid": "Fulton-Benjamin-J"
},
{
"family_name": "Gelino",
"given_name": "Christopher",
"clpid": "Gelino-Christopher-R"
},
{
"family_name": "Helou",
"given_name": "George",
"orcid": "0000-0003-3367-3415",
"clpid": "Helou-G"
},
{
"family_name": "Henderson",
"given_name": "Calen B.",
"orcid": "0000-0001-8877-9060",
"clpid": "Henderson-Calen-B"
},
{
"family_name": "Howell",
"given_name": "Justin",
"orcid": "0000-0001-6028-8059",
"clpid": "Howell-Justin-H"
},
{
"family_name": "Kim",
"given_name": "Joyce",
"clpid": "Kim-Joyce"
},
{
"family_name": "Landais",
"given_name": "Gilles",
"orcid": "0000-0003-4868-5873"
},
{
"family_name": "Lo",
"given_name": "Tak",
"clpid": "Lo-Tak"
},
{
"family_name": "Loup",
"given_name": "C\u00e9cile"
},
{
"family_name": "Madore",
"given_name": "Barry",
"orcid": "0000-0002-1576-1676"
},
{
"family_name": "Monari",
"given_name": "Giacomo",
"orcid": "0000-0002-6863-0661"
},
{
"family_name": "Muench",
"given_name": "August",
"orcid": "0000-0003-0666-6367"
},
{
"family_name": "Oberto",
"given_name": "Ana\u00efs",
"orcid": "0000-0001-7141-1542"
},
{
"family_name": "Ocvirk",
"given_name": "Pierre",
"orcid": "0000-0002-8488-504X"
},
{
"family_name": "Peek",
"given_name": "Joshua E. G.",
"orcid": "0000-0003-4797-7030"
},
{
"family_name": "Perret",
"given_name": "Emmanuelle",
"orcid": "0000-0002-4068-8175"
},
{
"family_name": "Pevunova",
"given_name": "Olga",
"clpid": "Pevunova-Olga"
},
{
"family_name": "Ramirez",
"given_name": "Solange V."
},
{
"family_name": "Rebull",
"given_name": "Luisa",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Shemmer",
"given_name": "Ohad",
"orcid": "0000-0003-4327-1460"
},
{
"family_name": "Smale",
"given_name": "Alan",
"orcid": "0000-0001-9207-9796"
},
{
"family_name": "Tam",
"given_name": "Raymond",
"clpid": "Tam-Raymond"
},
{
"family_name": "Terek",
"given_name": "Scott",
"clpid": "Terek-Scott"
},
{
"family_name": "Van Orsow",
"given_name": "Doug",
"orcid": "0000-0001-8405-0264"
},
{
"family_name": "Vannier",
"given_name": "Patricia"
},
{
"family_name": "Wang",
"given_name": "Shin-Ywan",
"clpid": "Wang-Shin-Ywan"
}
],
"abstract": "We present an overview of best practices for publishing data in astronomy and astrophysics journals. These recommendations are intended as a reference for authors to help prepare and publish data in a way that will better represent and support science results, enable better data sharing, improve reproducibility, and enhance the reusability of data. Observance of these guidelines will also help to streamline the extraction, preservation, integration and cross-linking of valuable data from astrophysics literature into major astronomical databases, and consequently facilitate new modes of science discovery that will better exploit the vast quantities of panchromatic and multidimensional data associated with the literature. We encourage authors, journal editors, referees, and publishers to implement the best practices reviewed here, as well as related recommendations from international astronomical organizations such as the International Astronomical Union for publication of nomenclature, data, and metadata. A convenient Checklist of Recommendations for Publishing Data in the Literature (Appendix A) is included for authors to consult before the submission of the final version of their journal articles and associated data files. We recommend that publishers of journals in astronomy and astrophysics incorporate a link to this document in their Instructions to Authors.",
"doi": "10.3847/1538-4365/ac6268",
"issn": "0067-0049",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal Supplement Series",
"publication_date": "2022-05",
"series_number": "1",
"volume": "260",
"issue": "1",
"pages": "Art. No. 5"
},
{
"id": "authors:dxmfg-grt89",
"collection": "authors",
"collection_id": "dxmfg-grt89",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221017-15547800.43",
"type": "article",
"title": "NITARP, the NASA/IPAC Teacher Archive Research Program",
"author": [
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
}
],
"abstract": "Have you ever wanted to get into astronomical data? I mean REALLY into astronomical data? The NASA/IPAC Teacher Archive Research Program (NITARP) gets teachers involved with real astronomy data and research. We partner small groups of (largely) high school educators with a professional astronomer mentor for an original research project. The educators incorporate the experience into their classrooms and share their experience with other teachers. The program runs for a full year, January through January. Applications are available annually: posted in May and closed in September.\nREFERENCES",
"doi": "10.1119/10.0010004",
"issn": "0031-921X",
"publisher": "American Association of Physics Teachers",
"publication": "Physics Teacher",
"publication_date": "2022-04",
"series_number": "4",
"volume": "60",
"issue": "4",
"pages": "312-313"
},
{
"id": "authors:1x476-cyq58",
"collection": "authors",
"collection_id": "1x476-cyq58",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220118-993989000",
"type": "article",
"title": "The Rate, Amplitude, and Duration of Outbursts from Class 0 Protostars in Orion",
"author": [
{
"family_name": "Zakri",
"given_name": "Wafa",
"orcid": "0000-0001-9030-1832",
"clpid": "Zakri-Wafa"
},
{
"family_name": "Megeath",
"given_name": "S. T.",
"orcid": "0000-0001-7629-3573",
"clpid": "Megeath-S-Thomas"
},
{
"family_name": "Fischer",
"given_name": "William J.",
"orcid": "0000-0002-3747-2496",
"clpid": "Fischer-William-J"
},
{
"family_name": "Gutermuth",
"given_name": "Robert",
"orcid": "0000-0002-6447-899X",
"clpid": "Gutermuth-Robert-A"
},
{
"family_name": "Furlan",
"given_name": "Elise",
"orcid": "0000-0001-9800-6248",
"clpid": "Furlan-Elise"
},
{
"family_name": "Hartmann",
"given_name": "Lee",
"orcid": "0000-0003-1430-8519",
"clpid": "Hartmann-Lee-W"
},
{
"family_name": "Karnath",
"given_name": "Nicole",
"orcid": "0000-0003-3682-854X",
"clpid": "Karnath-Nicole"
},
{
"family_name": "Osorio",
"given_name": "Mayra",
"orcid": "0000-0002-6737-5267",
"clpid": "Osorio-Mayra"
},
{
"family_name": "Safron",
"given_name": "Emily",
"orcid": "0000-0002-6872-2582",
"clpid": "Safron-Emily"
},
{
"family_name": "Stanke",
"given_name": "Thomas",
"orcid": "0000-0002-5812-9232",
"clpid": "Stanke-Thomas"
},
{
"family_name": "Stutz",
"given_name": "Amelia M.",
"orcid": "0000-0003-2300-8200",
"clpid": "Stutz-Amelia-M"
},
{
"family_name": "Tobin",
"given_name": "John J.",
"orcid": "0000-0002-6195-0152",
"clpid": "Tobin-John-J"
},
{
"family_name": "Allen",
"given_name": "Thomas S.",
"clpid": "Allen-Thomas-S"
},
{
"family_name": "Federman",
"given_name": "Sam",
"orcid": "0000-0002-6136-5578",
"clpid": "Federman-Sam"
},
{
"family_name": "Habel",
"given_name": "Nolan",
"orcid": "0000-0002-2667-1676",
"clpid": "Habel-Nolan-M"
},
{
"family_name": "Manoj",
"given_name": "P.",
"orcid": "0000-0002-3530-304X",
"clpid": "Manoj-Puravankara"
},
{
"family_name": "Narang",
"given_name": "Mayank",
"orcid": "0000-0002-0554-1151",
"clpid": "Narang-Mayank"
},
{
"family_name": "Pokhrel",
"given_name": "Riwaj",
"orcid": "0000-0002-0557-7349",
"clpid": "Pokhrel-Riwaj"
},
{
"family_name": "Rebull",
"given_name": "Luisa",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Sheehan",
"given_name": "Patrick D.",
"orcid": "0000-0002-9209-8708",
"clpid": "Sheehan-Patrick-D"
},
{
"family_name": "Watson",
"given_name": "Dan M.",
"orcid": "0000-0001-8302-0530",
"clpid": "Watson-Dan-M"
}
],
"abstract": "At least half of a protostar's mass is accreted in the Class 0 phase, when the central protostar is deeply embedded in a dense, infalling envelope. We present the first systematic search for outbursts from Class 0 protostars in the Orion clouds. Using photometry from Spitzer/IRAC spanning 2004 to 2017, we detect three outbursts from Class 0 protostars with \u22652 mag changes at 3.6 or 4.5 \u03bcm. This is comparable to the magnitude change of a known protostellar FU Ori outburst. Two are newly detected bursts from the protostars HOPS 12 and 124. The number of detections implies that Class 0 protostars burst every 438 yr, with a 95% confidence interval of 161 to 1884 yr. Combining Spitzer and WISE/NEOWISE data spanning 2004\u20132019, we show that the bursts persist for more than nine years with significant variability during each burst. Finally, we use 19\u2013100 \u03bcm photometry from SOFIA, Spitzer, and Herschel to measure the amplitudes of the bursts. Based on the burst interval, a duration of 15 yr, and the range of observed amplitudes, 3%\u2013100% of the mass accretion during the Class 0 phase occurs during bursts. In total, we show that bursts from Class 0 protostars are as frequent, or even more frequent, than those from more evolved protostars. This is consistent with bursts being driven by instabilities in disks triggered by rapid mass infall. Furthermore, we find that bursts may be a significant, if not dominant, mode of mass accretion during the Class 0 phase.",
"doi": "10.3847/2041-8213/ac46ae",
"issn": "2041-8205",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal Letters",
"publication_date": "2022-01-10",
"series_number": "2",
"volume": "924",
"issue": "2",
"pages": "Art. No. L23"
},
{
"id": "authors:nbg7j-d4k37",
"collection": "authors",
"collection_id": "nbg7j-d4k37",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220310-752837000",
"type": "article",
"title": "Real astronomy data for anyone: Explore NASA's IRSA",
"author": [
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
}
],
"abstract": "Many professional astronomy archives are open to the public; software tools are getting better all the time to not just access these data, but also work with them.1\u20132 The Infrared [IR] Science Archive (IRSA)3 is NASA's home for long-wavelength data, both space- and ground-based. You can use this interface to pull data to create your own lessons, or turn students loose in the archive to discover features of our multi-wavelength universe.",
"doi": "10.1119/10.0009117",
"issn": "0031-921X",
"publisher": "American Association of Physics Teachers",
"publication": "Physics Teacher",
"publication_date": "2022-01",
"series_number": "1",
"volume": "60",
"issue": "1",
"pages": "72-73"
},
{
"id": "authors:dv2tk-ds708",
"collection": "authors",
"collection_id": "dv2tk-ds708",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210204-092708651",
"type": "article",
"title": "Stellar Rotation in the Gaia Era: Revised Open Clusters' Sequences",
"author": [
{
"family_name": "Godoy-Rivera",
"given_name": "Diego",
"orcid": "0000-0003-4556-1277",
"clpid": "Godoy-Rivera-Diego"
},
{
"family_name": "Pinsonneault",
"given_name": "Marc H.",
"orcid": "0000-0002-7549-7766",
"clpid": "Pinsonneault-Marc-H"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
}
],
"abstract": "The period versus mass diagrams (i.e., rotational sequences) of open clusters provide crucial constraints for angular momentum evolution studies. However, their memberships are often heavily contaminated by field stars, which could potentially bias the interpretations. In this paper, we use data from Gaia DR2 to reassess the memberships of seven open clusters with ground- and space-based rotational data, and present an updated view of stellar rotation as a function of mass and age. We use the Gaia astrometry to identify the cluster members in phase space, and the photometry to derive revised ages and place the stars on a consistent mass scale. Applying our membership analysis to the rotational sequences reveals that: (1) the contamination in clusters observed from the ground can reach up to \u223c35%; (2) the overall fraction of rotational outliers decreases substantially when the field contaminants are removed, but some outliers persist; (3) there is a sharp upper edge in the rotation periods at young ages; (4) at young ages, stars in the 1.0\u20130.6M\u2299 range inhabit a global maximum of rotation periods, potentially providing an optimal window for habitable planets. Additionally, we see clear evidence for a strongly mass-dependent spin-down process. In the regime where rapid rotators are leaving the saturated domain, the rotational distributions broaden (in contradiction with popular models), which we interpret as evidence that the torque must be lower for rapid rotators than for intermediate ones. The cleaned rotational sequences from ground-based observations can be as constraining as those obtained from space.",
"doi": "10.3847/1538-4365/ac2058",
"issn": "0067-0049",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal Supplement Series",
"publication_date": "2021-12",
"series_number": "2",
"volume": "257",
"issue": "2",
"pages": "Art. No. 46"
},
{
"id": "authors:wm118-e5p43",
"collection": "authors",
"collection_id": "wm118-e5p43",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211208-559911000",
"type": "article",
"title": "Beyond the dips of V807 Tau, a spectropolarimetric study of a dipper's magnetosphere",
"author": [
{
"family_name": "Pouilly",
"given_name": "K.",
"orcid": "0000-0002-9628-2959",
"clpid": "Pouilly-Kim"
},
{
"family_name": "Bouvier",
"given_name": "J.",
"orcid": "0000-0002-7450-6712",
"clpid": "Bouvier-J\u00e8r\u00f4me"
},
{
"family_name": "Alecian",
"given_name": "E.",
"orcid": "0000-0001-5260-7179",
"clpid": "Alecian-Evelyne"
},
{
"family_name": "Alencar",
"given_name": "S. H. P.",
"orcid": "0000-0002-5171-8376",
"clpid": "Alencar-Silvia-H-P"
},
{
"family_name": "Cody",
"given_name": "A.-M.",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Donati",
"given_name": "J.-F.",
"orcid": "0000-0001-5541-2887",
"clpid": "Donati-Jean-Fran\u00e7ois"
},
{
"family_name": "Grankin",
"given_name": "K.",
"orcid": "0000-0001-5707-8448",
"clpid": "Grankin-Konstantin"
},
{
"family_name": "Rebull",
"given_name": "L.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Folsom",
"given_name": "C. P.",
"clpid": "Folsom-Colin-P"
}
],
"abstract": "Context. The so-called dippers are pre-main-sequence objects that accrete material from their circumstellar disks through the stellar magnetosphere. Their unique type of variability allows us to probe the magnetic star-disk interaction processes in young stellar objects. \n\nAims. We aim to characterize the magnetospheric accretion process in the young stellar object V807 Tau, one of the most stable dippers revealed by K2 in the Taurus star forming region. \n\nMethods. We performed photometric and spectropolarimetric follow-up observations of this system with CFHT/ESPaDOnS in order to investigate the variability of the system over several rotational periods. \n\nResults. We derive a 4.38 day period from the K2 dipper light curve. This period is also seen in the radial velocity variations, which we ascribe to spot modulation. The slightly redshifted narrow component of the He I 5876 \u00c5 line as well as the high velocity red wing of the H\u03b2 and H\u03b3 emission line profiles also vary in intensity with the same periodicity. The former traces the accretion shock at the stellar surface, and the latter is a signature of an accretion funnel flow crossing the line of sight. We derive a surface brightness map and the topology of the surface magnetic field from the modeling of Stokes I and V profiles, respectively, for photospheric lines and for the He I emission line. The latter reveals a bright spot at the stellar surface, located at a latitude of 60\u00b0, and a maximum field strength of \u223c2 kG at this location. The topology of the magnetic field at the stellar surface is dominated by a dipolar component inclined by about 40\u00b0 onto the spin axis. Variable blueshifted absorption components seen in the Balmer line profiles suggest episodic outflows. Despite of its clear and stable dipper behavior, we derive a relatively low inclination of 40\u00b0 to 50\u00b0 for this system, which calls question the origin of the dips. The low inclination we infer is also consistent with the absence of deep inverse P Cygni components in the line profiles. \n\nConclusions. We conclude that magnetospheric accretion is ongoing in V807 Tau, taking place through non-axisymmetric accretion funnel flows controlled by a strong, tilted, and mainly dipolar magnetic topology. Whether an inner disk warp resulting from this process can account for the dipper character of this source remains to be seen, given the low inclination of the system.",
"doi": "10.1051/0004-6361/202140850",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy and Astrophysics",
"publication_date": "2021-12",
"volume": "656",
"pages": "Art. No. A50"
},
{
"id": "authors:6jrs1-pqx66",
"collection": "authors",
"collection_id": "6jrs1-pqx66",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210914-225351966",
"type": "article",
"title": "Multicolor Variability of Young Stars in the Lagoon Nebula: Driving Causes and Intrinsic Timescales",
"author": [
{
"family_name": "Venuti",
"given_name": "Laura",
"orcid": "0000-0002-4115-0318",
"clpid": "Venuti-Laura"
},
{
"family_name": "Cody",
"given_name": "Ann Marie",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Beccari",
"given_name": "Giacomo",
"orcid": "0000-0002-3865-9906",
"clpid": "Beccari-Giacomo"
},
{
"family_name": "Irwin",
"given_name": "Mike J.",
"orcid": "0000-0002-2191-9038",
"clpid": "Irwin-Mike-J"
},
{
"family_name": "Thanvantri",
"given_name": "Sowmya",
"clpid": "Thanvantri-Sowmya"
},
{
"family_name": "Howell",
"given_name": "Steve B.",
"orcid": "0000-0002-2532-2853",
"clpid": "Howell-Steve-B"
},
{
"family_name": "Barentsen",
"given_name": "Geert",
"orcid": "0000-0002-3306-3484",
"clpid": "Barentsen-Geert"
}
],
"abstract": "Space observatories have provided unprecedented depictions of the many variability behaviors typical of low-mass, young stars. However, those studies have so far largely omitted more massive objects (\u223c2 M_\u2299 to 4\u20135 M_\u2299) and were limited by the absence of simultaneous, multiwavelength information. We present a new study of young star variability in the \u223c1\u20132 Myr old, massive Lagoon Nebula region. Our sample encompasses 278 young, late B to K-type stars, monitored with Kepler/K2. Auxiliary u, g, r, i, H\u03b1 time-series photometry, simultaneous with K2, was acquired at the Paranal Observatory. We employed this comprehensive data set and archival infrared photometry to determine individual stellar parameters, assess the presence of circumstellar disks, and tie the variability behaviors to inner disk dynamics. We found significant mass-dependent trends in variability properties, with B/A stars displaying substantially reduced levels of variability compared to G/K stars for any light-curve morphology. These properties suggest different magnetic field structures at the surface of early-type and later-type stars. We also detected a dearth of some disk-driven variability behaviors, particularly dippers, among stars earlier than G. This indicates that their higher surface temperatures and more chaotic magnetic fields prevent the formation and survival of inner disk dust structures corotating with the star. Finally, we examined the characteristic variability timescales within each light curve and determined that the day-to-week timescales are predominant over the K2 time series. These reflect distinct processes and locations in the inner disk environment, from intense accretion triggered by instabilities in the innermost disk regions to variable accretion efficiency in the outer magnetosphere.",
"doi": "10.3847/1538-3881/ac0536",
"issn": "0004-6256",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2021-09",
"series_number": "3",
"volume": "162",
"issue": "3",
"pages": "Art. No. 101"
},
{
"id": "authors:ybmsq-ztv05",
"collection": "authors",
"collection_id": "ybmsq-ztv05",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210722-140457513",
"type": "article",
"title": "The dipper population of Taurus seen with K2",
"author": [
{
"family_name": "Roggero",
"given_name": "Noemi",
"orcid": "0000-0003-4370-086X",
"clpid": "Roggero-Noemi"
},
{
"family_name": "Bouvier",
"given_name": "J\u00e8r\u00f4me",
"orcid": "0000-0002-7450-6712",
"clpid": "Bouvier-J\u00e8r\u00f4me"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Cody",
"given_name": "Ann Marie",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
}
],
"abstract": "Context. Dippers are typically low-mass, pre-main-sequence stars that display dips in their light curves. These dips have been attributed to dusty warps that form in the inner part of the disk. \n\nAims. Our goal is to derive the characteristics of dipper stars in Taurus to assess the physical mechanisms that induce dipper light curves. \n\nMethods. We used the light curves of the fourth and thirteenth campaigns of K2 to select a dipper sample among 179 members and possible members of the Taurus star-forming region based on the light-curve morphology. We studied the periodicities by combining periodograms with wavelet analysis and derived the stellar parameters of the sample from the photometry. We also studied the morphology of the photometric dips. \n\nResults. We find a dipper occurrence of ~30% in disk-bearing stars observed with K2 that were identified visually by us. This represents a lower limit to their true occurrence, on the one hand because they are ephemeral, and on the other because there are detection limits. About half of the dippers are aperiodic, and most of these are dominated by another type of variability. The chosen sample is of late spectral type (K/M), low mass (mostly <1 M_\u2299), and moderate mass accretion rates and has periods of a few days. We observed a transient dipper over a few rotation cycles and observed a dipper with a changing period. The structure of the dips can be complex and varies strongly over timescales of down to one stellar rotation. The corotation radii are located at a few stellar radii, and the temperatures at corotation allow dust survival. Many of the systems are seen at moderate to high inclination. We find that the angular extension of the dusty structure producing the dips is correlated with the stellar period. \n\nConclusions. Magnetospheric accretion, which causes an accretion column and its base to occult the star, can explain most of the observed light curves. Although compatible with the model, many of the stellar inclination angles are moderate and do not exclude mechanisms other than the occultation by an inner disk warp to account for dipper light curves.",
"doi": "10.1051/0004-6361/202140646",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy and Astrophysics",
"publication_date": "2021-07",
"volume": "651",
"pages": "Art. No. A44"
},
{
"id": "authors:rr6w3-xab83",
"collection": "authors",
"collection_id": "rr6w3-xab83",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210204-092654941",
"type": "article",
"title": "Outbursting Young Stellar Object PGIR 20dci in the Perseus Arm",
"author": [
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "De",
"given_name": "Kishalay",
"orcid": "0000-0002-8989-0542",
"clpid": "De-Kishalay"
},
{
"family_name": "Hankins",
"given_name": "Matthew",
"orcid": "0000-0001-9315-8437",
"clpid": "Hankins-Matthew-J"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Lau",
"given_name": "Ryan M.",
"clpid": "Lau-Ryan-M"
},
{
"family_name": "Cutri",
"given_name": "Roc M.",
"orcid": "0000-0002-0077-2305",
"clpid": "Cutri-Roc-M"
},
{
"family_name": "Ashley",
"given_name": "Michael C. B.",
"orcid": "0000-0003-1412-2028",
"clpid": "Ashley-Michael-C-B"
},
{
"family_name": "Karambelkar",
"given_name": "Viraj R.",
"orcid": "0000-0003-2758-159X",
"clpid": "Karambelkar-Viraj-R"
},
{
"family_name": "Moore",
"given_name": "Anna M.",
"orcid": "0000-0002-2894-6936",
"clpid": "Moore-Anna-M"
},
{
"family_name": "Travouillon",
"given_name": "T.",
"orcid": "0000-0001-9304-6718",
"clpid": "Travouillon-Tony-D"
},
{
"family_name": "Mainzer",
"given_name": "A. K.",
"clpid": "Mainzer-Amy-K"
}
],
"abstract": "We report the discovery of a likely outbursting Class I young stellar object, associated with the star-forming region NGC 281-W (distance ~2.8 kpc). The source is currently seen only at infrared wavelengths, appearing in both the Palomar Gattini InfraRed (1.2 \u03bcm) and the Near-Earth Object Wide-field Infrared Survey Explorer (3.4 and 4.6 \u03bcm) photometric time-domain surveys. Recent near-infrared imaging reveals a new, extended scattered light nebula. Recent near-infrared spectroscopy confirms the similarity of PGIR 20dci to FU Ori\u2013type sources, based on strong molecular absorption in CO, H\u2082O, and OH; weak absorption in several atomic lines; and a warm wind/outflow as indicated by a P Cygni profile in the He I \u03bb10830 line. This is a rare case of an FU Ori star with a well-measured long-term photometric rise before a sharper outburst, and the second instance of an FU Ori star with a documented two-step brightening in the mid-infrared.",
"doi": "10.3847/1538-3881/abe406",
"issn": "1538-3881",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2021-05",
"series_number": "5",
"volume": "161",
"issue": "5",
"pages": "Art. No. 220"
},
{
"id": "authors:my122-6th70",
"collection": "authors",
"collection_id": "my122-6th70",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201203-151008360",
"type": "article",
"title": "Even More Rapidly Rotating Pre-main-sequence M Dwarfs with Highly Structured Light Curves: An Initial Survey in the Lower Centaurus-Crux and Upper Centaurus-Lupus Associations",
"author": [
{
"family_name": "Stauffer",
"given_name": "John",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Jardine",
"given_name": "Moira",
"orcid": "0000-0002-1466-5236",
"clpid": "Jardine-Moira"
},
{
"family_name": "Cameron",
"given_name": "Andrew Collier",
"orcid": "0000-0002-8863-7828",
"clpid": "Cameron-Andrew-Collier"
},
{
"family_name": "Cody",
"given_name": "Ann Marie",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Barrado",
"given_name": "David",
"orcid": "0000-0002-5971-9242",
"clpid": "Barrado-David"
},
{
"family_name": "Kruse",
"given_name": "Ethan",
"orcid": "0000-0002-0493-1342",
"clpid": "Kruse-Ethan"
},
{
"family_name": "Powell",
"given_name": "Brian P.",
"clpid": "Powell-Brian-P"
}
],
"abstract": "Using K2, we recently discovered a new type of periodic photometric variability while analyzing the light curves of members of Upper Sco. The 23 exemplars of this new variability type are all mid-M dwarfs, with short rotation periods. Their phased light curves have one or more broad flux dips or multiple arcuate structures which are not explicable by photospheric spots or eclipses by solid bodies. Now, using Transiting Exoplanet Survey Satellite data, we have searched for this type of variability in the other major sections of Sco-Cen, Upper Centaurus-Lupus (UCL), and Lower Centaurus-Crux (LCC). We identify 28 stars with the same light curve morphologies. We find no obvious difference between the Upper Sco and the UCL/LCC representatives of this class in terms of their light curve morphologies, periods, or variability amplitudes. The physical mechanism behind this variability is unknown, but as a possible clue we show that the rapidly rotating mid-M dwarfs in UCL/LCC have slightly different colors from the slowly rotating M dwarfs\u2014they either have a blue excess (hot spots?) or a red excess (warm dust?). One of the newly identified stars (TIC242407571) has a very striking light curve morphology. At about every 0.05 in phase are features that resemble icicles. The icicles arise because there is a second periodic system whose main feature is a broad flux dip. Using a toy model, we show that the observed light curve morphology results only if the ratio of the two periods and the flux-dip width are carefully arranged.",
"doi": "10.3847/1538-3881/abc7c6",
"issn": "1538-3881",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2021-02",
"series_number": "2",
"volume": "161",
"issue": "2",
"pages": "Art. No. 60"
},
{
"id": "authors:8yx27-fdd11",
"collection": "authors",
"collection_id": "8yx27-fdd11",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210821-142428946",
"type": "book_section",
"title": "The growing legacy of a Great Observatory: Spitzer publications",
"book_title": "Observatory Operations: Strategies, Processes, and Systems VIII",
"author": [
{
"family_name": "Scire",
"given_name": "Elena",
"clpid": "Scire-Elena"
},
{
"family_name": "Rebull",
"given_name": "Luisa",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Krick",
"given_name": "Jessica",
"orcid": "0000-0002-2413-5976",
"clpid": "Krick-Jessica-E"
}
],
"contributor": [
{
"family_name": "Adler",
"given_name": "David S.",
"clpid": "Adler-David-S"
},
{
"family_name": "Seaman",
"given_name": "Robert L.",
"clpid": "Seaman-Robert-L"
},
{
"family_name": "Benn",
"given_name": "Chris R.",
"clpid": "Benn-Chris-R"
}
],
"abstract": "After 16.5 years the Spitzer Space Telescope was decommissioned on 30Jan2020. We present a look at the legacy of Spitzer: the 9200+ papers that have used data from the telescope and are catalogued in the Spitzer Bibliographical Database. Over the lifetime of this Great Observatory, cryogenic depletion and budget constraints brought on operational changes that in turn impacted the publication rates. This paper looks into the differences in publication rates between the Spitzer cryogenic and warm missions, and identifies those fields on the sky with especially high data reuse rates and many papers. In addition it provides a look into the citations of Spitzer fundamental papers, as well as how well authors identified the data they used. From data that were used once, to data that were used many times; the legacy of the Spitzer mission continues to grow even after the data collection has finished, and its full impact will not be known for years to come.",
"doi": "10.1117/12.2562801",
"isbn": "9781510636859",
"publisher": "Society of Photo-Optical Instrumentation Engineers",
"place_of_publication": "Bellingham, WA",
"publication_date": "2020-12-13",
"pages": "Art. No. 114491N"
},
{
"id": "authors:mvfk1-30n54",
"collection": "authors",
"collection_id": "mvfk1-30n54",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200526-142433014",
"type": "article",
"title": "Rotation of Low-mass Stars in Taurus with K2",
"author": [
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Stauffer",
"given_name": "J. R.",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Cody",
"given_name": "A. M.",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Hillenbrand",
"given_name": "L. A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Bouvier",
"given_name": "J.",
"orcid": "0000-0002-7450-6712",
"clpid": "Bouvier-J\u00e8r\u00f4me"
},
{
"family_name": "Roggero",
"given_name": "N.",
"orcid": "0000-0003-4370-086X",
"clpid": "Roggero-Noemi"
},
{
"family_name": "David",
"given_name": "T. J.",
"orcid": "0000-0001-6534-6246",
"clpid": "David-Trevor-J"
}
],
"abstract": "We present an analysis of K2 light curves (LCs) from Campaigns 4 and 13 for members of the young (~3 Myr) Taurus association, in addition to an older (~30 Myr) population of stars that is largely in the foreground of the Taurus molecular clouds. Out of 156 of the highest-confidence Taurus members, we find that 81% are periodic. Our sample of young foreground stars is biased and incomplete, but nearly all stars (37/38) are periodic. The overall distribution of rotation rates as a function of color (a proxy for mass) is similar to that found in other clusters: the slowest rotators are among the early M spectral types, with faster rotation toward both earlier FGK and later M types. The relationship between period and color/mass exhibited by older clusters such as the Pleiades is already in place by Taurus age. The foreground population has very few stars but is consistent with the USco and Pleiades period distributions. As found in other young clusters, stars with disks rotate on average slower, and few with disks are found rotating faster than ~2 days. The overall amplitude of the LCs decreases with age, and higher-mass stars have generally lower amplitudes than lower-mass stars. Stars with disks have on average larger amplitudes than stars without disks, though the physical mechanisms driving the variability and the resulting LC morphologies are also different between these two classes.",
"doi": "10.3847/1538-3881/ab893c",
"issn": "1538-3881",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2020-06",
"series_number": "6",
"volume": "159",
"issue": "6",
"pages": "Art. No. 273"
},
{
"id": "authors:djr95-sg007",
"collection": "authors",
"collection_id": "djr95-sg007",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190515-082941689",
"type": "article",
"title": "A warm Jupiter-sized planet transiting the pre-main sequence star V1298 Tau",
"author": [
{
"family_name": "David",
"given_name": "Trevor J.",
"orcid": "0000-0001-6534-6246",
"clpid": "David-Trevor-J"
},
{
"family_name": "Cody",
"given_name": "Ann Marie",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "Hedges",
"given_name": "Christina L.",
"orcid": "0000-0002-3385-8391",
"clpid": "Hedges-Christina-L"
},
{
"family_name": "Mamajek",
"given_name": "Eric E.",
"orcid": "0000-0003-2008-1488",
"clpid": "Mamajek-Eric-E"
},
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Ciardi",
"given_name": "David R.",
"orcid": "0000-0002-5741-3047",
"clpid": "Ciardi-David-R"
},
{
"family_name": "Beichman",
"given_name": "Charles A.",
"orcid": "0000-0002-5627-5471",
"clpid": "Beichman-Charles-A"
},
{
"family_name": "Petigura",
"given_name": "Erik A.",
"orcid": "0000-0003-0967-2893",
"clpid": "Petigura-Erik-A"
},
{
"family_name": "Fulton",
"given_name": "Benjamin J.",
"orcid": "0000-0003-3504-5316",
"clpid": "Fulton-Benjamin-J"
},
{
"family_name": "Isaacson",
"given_name": "Howard T.",
"orcid": "0000-0002-0531-1073",
"clpid": "Isaacson-Howard-T"
},
{
"family_name": "Howard",
"given_name": "Andrew W.",
"orcid": "0000-0001-8638-0320",
"clpid": "Howard-A-W"
},
{
"family_name": "Gagn\u00e9",
"given_name": "Jonathan",
"orcid": "0000-0002-2592-9612",
"clpid": "Gagn\u00e9-Jonathan"
},
{
"family_name": "Saunders",
"given_name": "Nicholas K.",
"clpid": "Saunders-Nicholas-K"
},
{
"family_name": "Rebull",
"given_name": "Luisa M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Stauffer",
"given_name": "John R.",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Vasisht",
"given_name": "Gautam",
"orcid": "0000-0002-1871-6264",
"clpid": "Vasisht-Gautam"
},
{
"family_name": "Hinkley",
"given_name": "Sasha",
"orcid": "0000-0001-8074-2562",
"clpid": "Hinkley-Sasha"
}
],
"abstract": "We report the detection of V1298 Tau b, a warm Jupiter-sized planet (R_P = 0.91 \u00b1 0.05 R_(Jup), P = 24.1 days) transiting a young solar analog with an estimated age of 23 Myr. The star and its planet belong to Group 29, a young association in the foreground of the Taurus\u2013Auriga star-forming region. While hot Jupiters have been previously reported around young stars, those planets are non-transiting and near-term atmospheric characterization is not feasible. The V1298 Tau system is a compelling target for follow-up study through transmission spectroscopy and Doppler tomography owing to the transit depth (0.5%), host star brightness (K_s = 8.1 mag), and rapid stellar rotation (v sin i = 23 km s^(\u22121)). Although the planet is Jupiter-sized, its mass is currently unknown due to high-amplitude radial velocity jitter. Nevertheless, V1298 Tau b may help constrain formation scenarios for at least one class of close-in exoplanets, providing a window into the nascent evolution of planetary interiors and atmospheres.",
"doi": "10.3847/1538-3881/ab290f",
"issn": "1538-3881",
"publisher": "American Astronomical Society",
"publication": "Astronomical Journal",
"publication_date": "2019-08",
"series_number": "2",
"volume": "158",
"issue": "2",
"pages": "Art. No. 79"
},
{
"id": "authors:g59q2-40880",
"collection": "authors",
"collection_id": "g59q2-40880",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151215-115259134",
"type": "article",
"title": "YSOVAR: Mid-Infrared Variability in NGC 1333",
"author": [
{
"family_name": "Rebull",
"given_name": "L. M.",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Stauffer",
"given_name": "J. R.",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Cody",
"given_name": "A. M.",
"orcid": "0000-0002-3656-6706",
"clpid": "Cody-Ann-Marie"
},
{
"family_name": "G\u00fcnther",
"given_name": "H. M.",
"orcid": "0000-0003-4243-2840",
"clpid": "G\u00fcnther-Hans-Moritz"
},
{
"family_name": "Hillenbrand",
"given_name": "L. A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Poppenhaeger",
"given_name": "K.",
"clpid": "Poppenhaeger-Katja"
},
{
"family_name": "Wolk",
"given_name": "S. J.",
"orcid": "0000-0002-0826-9261",
"clpid": "Wolk-Scott-J"
},
{
"family_name": "Hora",
"given_name": "J. L.",
"orcid": "0000-0002-5599-4650",
"clpid": "Hora-Joseph-L"
},
{
"family_name": "Hernandez",
"given_name": "J.",
"clpid": "Hernandez-J"
},
{
"family_name": "Bayo",
"given_name": "A.",
"orcid": "0000-0001-7868-7031",
"clpid": "Bayo-Amelia"
},
{
"family_name": "Covey",
"given_name": "K.",
"orcid": "0000-0001-6914-7797",
"clpid": "Covey-Kevin-R"
},
{
"family_name": "Forbrich",
"given_name": "J.",
"clpid": "Forbrich-J"
},
{
"family_name": "Gutermuth",
"given_name": "R.",
"orcid": "0000-0002-6447-899X",
"clpid": "Gutermuth-Robert-A"
},
{
"family_name": "Morales-Calder\u00f3n",
"given_name": "M.",
"clpid": "Morales-Calder\u00f3n-Maria"
},
{
"family_name": "Plavchan",
"given_name": "P.",
"orcid": "0000-0002-8864-1667",
"clpid": "Plavchan-Peter"
},
{
"family_name": "Song",
"given_name": "I.",
"orcid": "0000-0002-5815-7372",
"clpid": "Song-Inseok"
},
{
"family_name": "Bouy",
"given_name": "H.",
"orcid": "0000-0002-7084-487X",
"clpid": "Bouy-Herv\u00e9"
},
{
"family_name": "Terebey",
"given_name": "S.",
"clpid": "Terebey-S"
},
{
"family_name": "Cuillandre",
"given_name": "J. C.",
"clpid": "Cuillandre-J-C"
},
{
"family_name": "Allen",
"given_name": "L. E.",
"clpid": "Allen-L-E"
}
],
"abstract": "As part of the Young Stellar Object VARiability (YSOVAR) program, we monitored NGC 1333 for ~35 days at 3.6 and 4.5 um using the Spitzer Space Telescope. We report here on the mid-infrared variability of the point sources in the ~ 10 X ~ 20 area centered on 03:29:06, +31:19:30 (J2000). Out of 701 light curves in either channel, we find 78 variables over the YSOVAR campaign. About half of the members are variable. The variable fraction for the most embedded SEDs (Class I, flat) is higher than that for less embedded SEDs (Class II), which is in turn higher than the star-like SEDs (Class III). A few objects have amplitudes (10-90th percentile brightness) in [3.6] or [4.5]>0.2 mag; a more typical amplitude is 0.1-0.15 mag. The largest color change is >0.2 mag. There are 24 periodic objects, with 40% of them being flat SED class. This may mean that the periodic signal is primarily from the disk, not the photosphere, in those cases. We find 9 variables likely to be 'dippers', where texture in the disk occults the central star, and 11 likely to be 'bursters', where accretion instabilities create brightness bursts. There are 39 objects that have significant trends in [3.6]-[4.5] color over the campaign, about evenly divided between redder-when-fainter (consistent with extinction variations) and bluer-when-fainter. About a third of the 17 Class 0 and/or jet-driving sources from the literature are variable over the YSOVAR campaign, and a larger fraction (~half) are variable between the YSOVAR campaign and the cryogenic-era Spitzer observations (6-7 years), perhaps because it takes time for the envelope to respond to changes in the central source. The NGC 1333 brown dwarfs do not stand out from the stellar light curves in any way except there is a much larger fraction of periodic objects (~60% of variable brown dwarfs are periodic, compared to ~30% of the variables overall).",
"doi": "10.1088/0004-6256/150/6/175",
"issn": "0004-6256",
"publisher": "Astronomical Journal",
"publication": "Astronomical Journal",
"publication_date": "2015-12-19",
"series_number": "6",
"volume": "150",
"issue": "6",
"pages": "Art. No."
},
{
"id": "authors:wc0qf-htc85",
"collection": "authors",
"collection_id": "wc0qf-htc85",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230329-630795000.2",
"type": "book_section",
"title": "Star Formation: Answering Fundamental Questions During the Spitzer Warm Mission Phase",
"book_title": "The Science Opportunities of the Warm Spitzer Mission Workshop",
"author": [
{
"family_name": "Strom",
"given_name": "Steve",
"clpid": "Strom-Steven"
},
{
"family_name": "Allen",
"given_name": "Lori",
"orcid": "0000-0002-7789-5119",
"clpid": "Allen-Lori-E"
},
{
"family_name": "Carpenter",
"given_name": "John",
"orcid": "0000-0003-2251-0602",
"clpid": "Carpenter-John-M"
},
{
"family_name": "Hartmann",
"given_name": "Lee",
"orcid": "0000-0003-1430-8519",
"clpid": "Hartmann-Lee-W"
},
{
"family_name": "Megeath",
"given_name": "S. Thomas",
"orcid": "0000-0001-7629-3573",
"clpid": "Megeath-S-Thomas"
},
{
"family_name": "Rebull",
"given_name": "Luisa",
"orcid": "0000-0001-6381-515X",
"clpid": "Rebull-Luisa-M"
},
{
"family_name": "Stauffer",
"given_name": "John R.",
"orcid": "0000-0003-3595-7382",
"clpid": "Stauffer-John-R"
},
{
"family_name": "Liu",
"given_name": "Michael",
"orcid": "0000-0003-2232-7664",
"clpid": "Liu-Michael-C"
}
],
"contributor": [
{
"family_name": "Storrie-Lombardi",
"given_name": "Lisa J.",
"orcid": "0000-0002-5987-5210",
"clpid": "Storrie-Lombardi-Lisa-J"
},
{
"family_name": "Silbermann",
"given_name": "Nancy A.",
"clpid": "Silbermann-Nancy-A"
}
],
"abstract": "Through existing studies of star\u2010forming regions, Spitzer has created rich databases which have already profoundly influenced our ability to understand the star and planet formation process on micro and macro scales. However, it is essential to note that Spitzer observations to date have focused largely on deep observations of regions of recent star formation associated directly with well\u2010known molecular clouds located within 500 pc. What has not been done is to explore to sufficient depth or breadth a representative sample of the much larger regions surrounding the more massive of these molecular clouds. Also, while there have been targeted studies of specific distant star forming regions, in general, there has been little attention devoted to mapping and characterizing the stellar populations and star\u2010forming histories of the surrounding giant molecular clouds (GMCs). As a result, we have yet to develop an understanding of the major physical processes that control star formation on the scale or spiral arms. Doing so will allow much better comparison of star\u2010formation in our galaxy to the star\u2010forming complexes that dominate the spiral arms of external galaxies. \n\nThe power of Spitzer in the Warm Mission for studies of star formation is its ability to carry out large\u2010scale surveys unbiased by prior knowledge of ongoing star formation or the presence of molecular clouds. The Spitzer Warm Mission will provide two uniquely powerful capabilities that promise equally profound advances : high sensitivity and efficient coverage of many hundreds of square degrees, and angular resolution sufficient to resolve dense groups and clusters of YSOs and to identify contaminating background galaxies whose colors mimic those of young stars. In this contribution, we describe two major programs: a survey of the outer regions of selected nearby OB associations, and a study of distant GMCs and star formation on the scale of a spiral arm.",
"doi": "10.1063/1.2806776",
"isbn": "978-0-7354-0457-1",
"publisher": "American Institute of Physics",
"place_of_publication": "Melville, NY",
"publication_date": "2007-06",
"pages": "137-156"
}
]