[ { "id": "authors:5p02e-8mk91", "collection": "authors", "collection_id": "5p02e-8mk91", "cite_using_url": "https://authors.library.caltech.edu/records/5p02e-8mk91", "type": "article", "title": "Atmospheric Characterization of Six Ultrahot Jupiters from K-band High-resolution Spectroscopy", "author": [ { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Inglis", "given_name": "Julie", "orcid": "0000-0001-9164-7966" }, { "family_name": "Agrawal", "given_name": "Shubh", "orcid": "0000-0003-2429-5811" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008", "clpid": "Delorme-Jacques-Robert" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato-Rovner", "given_name": "Jacklyn", "clpid": "Pezzato-Rovner-Jacklyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" } ], "abstract": "

We present new Keck/KPIC high-resolution spectroscopic detections of three ultrahot Jupiters (UHJs) in the K band: WASP-189 b (signal-to-noise ratio (SNR) = 7.2), MASCARA-1 b (SNR = 8.6), and TOI-1518 b (SNR = 7.1), as well as a tentative detection of KELT-9 b (SNR = 5.0). We perform a uniform set of atmospheric retrieval analysis on these objects, as well as previously reported KPIC observations of WASP-33 b (SNR = 11.2) and KELT-20 b (SNR = 10.5), We perform atmospheric retrievals for the pressure–temperature (P−T) profile, orbital velocity parameters, v sin i, and abundances of CO, H2O, OH, and Fe, with parameterized mixing profiles to account for the expected vertical abundance variations of H2O and OH. We also perform a set of retrievals assuming chemical equilibrium, which are generally in good agreement with the free retrievals. Except for KELT-9 b, the retrieved spectra are dominated by CO emission features, with additional weak H2O or OH features consistent with thermal dissociation of H2O. KELT-9 b, which is significantly hotter, appears to have very weak molecular features. Dissociation limits our ability to reliably constrain H2O or OH abundances from K-band data alone, resulting in poor constraints on the C/O ratio. For all objects, the atmospheric abundances from detected carbon and oxygen species are 1–10 × solar. These results highlight the importance of wide spectral coverage for high-resolution retrievals. Additional observations to expand phase and wavelength coverage are needed to better constrain oxygen species and possible spatial inhomogeneities from dissociation.

", "doi": "10.3847/1538-3881/ae88f6", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2026-08", "series_number": "2", "volume": "172", "issue": "2", "pages": "119" }, { "id": "authors:98hkr-t5c05", "collection": "authors", "collection_id": "98hkr-t5c05", "cite_using_url": "https://authors.library.caltech.edu/records/98hkr-t5c05", "type": "article", "title": "Distinct Rotational Evolution of Giant Planets and Brown Dwarf Companions", "author": [ { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Zhang", "given_name": "Yapeng", "orcid": "0000-0003-0097-4414", "clpid": "Zhang-Yapeng" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Cronin", "given_name": "Julianne", "orcid": "0000-0003-1172-5755" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Doppmann", "given_name": "Gregory W." }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Konopacky", "given_name": "Quinn M.", "orcid": "0000-0002-9936-6285" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" } ], "abstract": "

We present a rotational velocity (v sin i) survey of 32 stellar/substellar objects and giant planets using Keck/KPIC high-resolution spectroscopy, including 6 giant planets (2–7 MJup) and 25 substellar/stellar companions (12–88 MJup). Adding companions with spin measurements from the literature, we construct a curated spin sample for 43 benchmark stellar/substellar companions and giant planets and 54 free-floating brown dwarfs and planetary mass objects. We compare their spins, parameterized as fractional breakup velocities at 10 Myr, assuming constant angular momentum evolution. We find the first clear evidence that giant planets exhibit distinct spins versus low-mass brown dwarf companions (10–40 MJup) at 4–4.5σ significance assuming inclinations aligned with their orbits, while under randomly oriented inclinations the significance is at 1.6–2.1σ. Our findings hold when considering various assumptions about planets, and the mass ratio below 0.8% gives a clean cut for rotation between giant planets and brown dwarf companions. The higher fractional breakup velocities of planets can be interpreted as less angular momentum loss through circumplanetary disk braking during the planet formation phase. Brown dwarf companions exhibit evidence of slower rotation compared to isolated brown dwarfs, while planets and planetary mass objects show similar spins. Finally, our analysis of specific angular momentum versus age of 221 stellar/substellar objects below 0.1 M\u2299 with spin measurements in the literature indicates that the substellar objects of 5–40 MJup retain much higher angular momenta compared to stellar and substellar objects of 40–100 MJup after 10 Myr, when their initial angular momenta were set.

", "doi": "10.3847/1538-3881/ae434b", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2026-04", "series_number": "4", "volume": "171", "issue": "4", "pages": "224" }, { "id": "authors:zwje1-kjy56", "collection": "authors", "collection_id": "zwje1-kjy56", "cite_using_url": "https://authors.library.caltech.edu/records/zwje1-kjy56", "type": "article", "title": "Possible Stratospheric Emission in the Warm Neptune GJ 436 b from High-resolution Spectroscopy", "author": [ { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008", "clpid": "Delorme-Jacques-Robert" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Inglis", "given_name": "Julie", "orcid": "0000-0001-9164-7966", "clpid": "Inglis-Julie" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato-Rovner", "given_name": "Jacklyn", "clpid": "Pezzato-Rovner-Jacklyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" } ], "abstract": "
\n

We present high-spectral-resolution L-band (2.91–3.85 μm) observations of the warm Neptune GJ 436 b from Keck II/KPIC. KPIC’s single-mode fiber feed reduces the L-band background by a factor of 30, significantly improving sensitivity compared to a seeing-limited spectrometer and enabling a tentative (signal-to-noise ratio of 3–4) cross-correlation detection of GJ 436 b with a thermally inverted atmospheric model. In contrast with recent results from JWST and high-resolution transmission spectroscopy, our retrieval analysis prefers the presence of H2O, and possibly CH4, molecular features in emission. The broadband continuum flux associated with the maximum-likelihood model is substantially higher than expected based on both the ∼670 K equilibrium temperature of GJ 436 b and previous results from low-resolution spectroscopy. We demonstrate that the loss of continuum information during the processing of high-resolution spectra makes our analysis effectively insensitive to the absolute continuum level of the planet, and that scaling the maximum-likelihood model to match the broadband flux measured from low-resolution observations of GJ 436 b results in a detection of similar strength in cross correlation. These results could be explained by a thermal inversion arising above a haze layer in the upper atmosphere of GJ 436 b. Further observations, ideally posteclipse in order to break the Kp–Δvsys degeneracy, are needed to clarify this possible detection. This work demonstrates the potential of L-band high-resolution spectroscopy for characterizing significantly smaller and cooler exoplanets compared with hot Jupiters.

\n
", "doi": "10.3847/1538-3881/ae47fa", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2026-04", "series_number": "4", "volume": "171", "issue": "4", "pages": "226" }, { "id": "authors:w04d7-4kc40", "collection": "authors", "collection_id": "w04d7-4kc40", "cite_using_url": "https://authors.library.caltech.edu/records/w04d7-4kc40", "type": "article", "title": "Chemical and Isotopic Homogeneity between the L Dwarf CD-35 2722 B and Its Early M Host Star", "author": [ { "family_name": "Wang", "given_name": "Gavin", "orcid": "0000-0003-3092-4418", "clpid": "Wang-Gavin" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Picos", "given_name": "Dar\u00edo Gonz\u00e1lez", "orcid": "0000-0001-9282-9462" }, { "family_name": "Zhang \u5f20", "given_name": "Zhoujian \u5468\u5065", "orcid": "0000-0002-3726-4881" }, { "family_name": "Zhang", "given_name": "Yapeng", "orcid": "0000-0003-0097-4414", "clpid": "Zhang-Yapeng" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Doppmann", "given_name": "Gregory W." }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato-Rovner", "given_name": "Jacklyn", "clpid": "Pezzato-Rovner-Jacklyn" }, { "family_name": "Phillips", "given_name": "Caprice L.", "orcid": "0000-0001-5610-5328" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" } ], "abstract": "

CD-35 2722 B is an L dwarf companion to the nearby, ∼50–200 Myr old M1 dwarf CD-35 2722 A. We present a detailed analysis of both objects using high-resolution ( R ∼ 35,000) K -band spectroscopy from the Keck Planet Imager and Characterizer combined with archival photometry. With a mass of 30 −4 + 5 M Jup (planet-to-host mass ratio 0.05) and projected separation of 67 ± 4 au from its host, CD-35 2722 B likely formed via gravitational instability. We explore whether the chemical composition of the system tells a similar story. Accounting for systematic uncertainties, we find [ M / H ] = − 0.16 −0.02 + 0.03 ( stat ) ± 0.25 ( sys ) dex and 12C/13C = 132 −14 +20 for the host, and [ M / H ] = 0.27 -0.06+0.07 ( stat ) ±0.12 (sys) dex, 12CO/13CO = 159 −24+33 (stat) −33+40 ( sys ), and C/O = 0.55 ± 0.01 (stat) ± 0.04 (sys) for the companion. The chemical compositions for the brown dwarf and host star agree within the 1.5 σ level, supporting a scenario where CD-35 2722 B formed via gravitational instability. We do not find evidence for clouds on CD-35 2722 B despite it being a photometrically red mid-L dwarf and thus expected to be quite cloudy. We retrieve a temperature structure that is more isothermal than models and investigate its impact on our measurements, finding that constraining the temperature structure to self-consistent models does not significantly impact our retrieved chemical properties. Our observations highlight the need for data from complementary wavelength ranges to verify the presence of aerosols in likely cloudy L dwarfs.

", "doi": "10.3847/1538-4357/ae232f", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2026-02-01", "series_number": "2", "volume": "997", "issue": "2", "pages": "195" }, { "id": "authors:tgbjs-vp574", "collection": "authors", "collection_id": "tgbjs-vp574", "cite_using_url": "https://authors.library.caltech.edu/records/tgbjs-vp574", "type": "article", "title": "Dynamical Architectures of S-type Transiting Planets in Binaries. II. A Dichotomy in Orbital Alignment of Small Planets in Close Binary Systems", "author": [ { "family_name": "Zhang \u5f20", "given_name": "Jingwen \u5a67 \u96ef", "orcid": "0000-0002-2696-2406" }, { "family_name": "Huber", "given_name": "Daniel", "orcid": "0000-0001-8832-4488" }, { "family_name": "Bottom", "given_name": "Michael", "orcid": "0000-0003-1341-5531" }, { "family_name": "Weiss", "given_name": "Lauren M.", "orcid": "0000-0002-3725-3058" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Kraus", "given_name": "Adam L.", "orcid": "0000-0001-9811-568X" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2 \u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Dai", "given_name": "Fei", "orcid": "0000-0002-8958-0683" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Clark", "given_name": "Catherine A.", "orcid": "0000-0002-2361-5812", "clpid": "Clark-Catherine-A" }, { "family_name": "Ciardi", "given_name": "David R.", "orcid": "0000-0002-5741-3047", "clpid": "Ciardi-David-R" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Doppmann", "given_name": "Gregory W." }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Howell", "given_name": "Steve B.", "orcid": "0000-0002-2532-2853" }, { "family_name": "Isaacson", "given_name": "Howard", "orcid": "0000-0002-0531-1073" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Lester", "given_name": "Kathryn V.", "orcid": "0000-0002-9903-9911" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato-Rovner", "given_name": "Jacklyn", "clpid": "Pezzato-Rovner-Jacklyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Van Zandt", "given_name": "Judah", "orcid": "0000-0002-4290-6826" } ], "abstract": "

Stellar multiplicity plays a crucial role in shaping planet formation and dynamical evolution. We present a survey of 54 TESS objects of interest (TOIs) within 300 pc that exhibit significant Hipparcos−Gaia astrometric accelerations. We identified 35 TOIs with stellar companions at projected separations between 0.″1 and 2″ (or 10–200 au). We also identified 12 TOIs that could host planetary-mass or brown dwarf companions, including six that are newly discovered. Furthermore, we perform 3D orbital characterization for 12 binaries hosting confirmed planets or planet candidates, allowing us to constrain the line-of-sight mutual inclination, Δ I_(los), between the planetary and binary orbits. Combining our sample with previous measurements, we apply Bayesian hierarchical analysis to a total of 26 binary systems with S-type transiting planets (r_p < 5 R⊕). Specifically, we fit the Δ I_(los) distribution with both single (Rayleigh) and mixture models (two-component Rayleigh and Rayleigh-isotropic mixture). We find the mixture models are strongly favored (log Z \u2273 13.9, or ≈5σ), indicating the observed planet-binary Δ I_(los) values likely originate from two underlying populations: one nearly aligned (σ\u2081 = 2 .°4_(−0.9)^(+0.7) and one with more scattered mutual inclinations (σ\u2082 = 23 .°6_(−7.1)^(+8.8). Alternatively, the misaligned systems can be equally well described by an isotropic distribution of inclinations. This observed dichotomy likely reflects different dynamical histories. Notably, the misaligned population only emerges in systems with stellar periastron distances >40 au, while systems with close-in or eccentric stellar companions (periastron distances <40 au) preserve planet−binary alignment.

", "doi": "10.3847/1538-3881/ae2309", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2026-02", "series_number": "2", "volume": "171", "issue": "2", "pages": "77" }, { "id": "authors:hnxw2-h7m13", "collection": "authors", "collection_id": "hnxw2-h7m13", "cite_using_url": "https://authors.library.caltech.edu/records/hnxw2-h7m13", "type": "article", "title": "The Watery Atmosphere of HD 209458 b Revealed by Joint K- and L-band High-resolution Spectroscopy", "author": [ { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Inglis", "given_name": "Julie", "orcid": "0000-0001-9164-7966", "clpid": "Inglis-Julie" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008", "clpid": "Delorme-Jacques-Robert" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato-Rovner", "given_name": "Jacklyn", "clpid": "Pezzato-Rovner-Jacklyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Wang", "given_name": "Jason J \u738b\u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Wang", "given_name": "Ji \u738b\u5409", "orcid": "0000-0002-4361-8885" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" } ], "abstract": "

We present a joint analysis of high-resolution K- and L-band observations of the benchmark hot Jupiter HD 209458 b from the Keck Planet Imager and Characterizer. One half-night of observations was obtained in each bandpass, covering similar preeclipse phases. The two epochs were then jointly analyzed using our atmospheric retrieval pipeline based on petitRADTRANS to constrain the atmospheric pressure–temperature profile and chemical composition. Consistent with recent results from JWST observations at lower spectral resolution, we obtain an oxygen-rich composition for HD 209458 b (C/O < 10−3 at 95% confidence) and a lower limit on the volatile metallicity similar to the solar value ([(C + O)/H] > −0.2 at 95% confidence). Leveraging the large spectral grasp of the multiband observations, we constrain the atmospheric H2O mixing ratio to log H\u2082O_(V MR) > -3.1 at 95% confidence, and obtain 95% upper limits on the atmospheric mixing ratios of CO (<10−4.8), CH4 (<10−4.5), NH3 (<10−5.8), H2S (<10−3.3), and HCN (<10−5.6). The limits on CH4, NH3, and HCN are consistent with recent results from JWST transmission spectroscopy, demonstrating the value of multiband, ground-based high-resolution spectroscopy for precisely constraining trace-species abundances in exoplanet atmospheres. The retrieved low-C/O, moderate-metallicity composition for HD 209458 b is consistent with formation scenarios involving late accretion of substantial quantities of oxygen-rich refractory solids and/or ices.

", "doi": "10.3847/1538-3881/adfb71", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2025-10", "series_number": "4", "volume": "170", "issue": "4", "pages": "223" }, { "id": "authors:fha2k-ptr36", "collection": "authors", "collection_id": "fha2k-ptr36", "cite_using_url": "https://authors.library.caltech.edu/records/fha2k-ptr36", "type": "article", "title": "Fringing analysis and forward modeling of Keck Planet Imager and Characterizer (KPIC) spectra", "author": [ { "family_name": "Horstman", "given_name": "Katelyn A.", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn-A" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Wang", "given_name": "Jason J.", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley-D" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Bond", "given_name": "Charlotte Z." }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Lopez", "given_name": "Ronald" }, { "family_name": "Martin", "given_name": "Emily C." }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Venenciano", "given_name": "Taylor", "orcid": "0000-0003-0122-8915" }, { "family_name": "Kent Wallace", "given_name": "James", "orcid": "0000-0001-5299-6899", "clpid": "Kent-Wallace-James" }, { "family_name": "Wang", "given_name": "Ji" }, { "family_name": "Wizinowich", "given_name": "Peter", "orcid": "0000-0002-1646-442X" } ], "abstract": "Keck Planet Imager and Characterizer (KPIC) combines high-contrast imaging with high-resolution spectroscopy (R\u223c35,000 in K band) to study directly imaged exoplanets and brown dwarfs in unprecedented detail. KPIC aims to spectrally characterize substellar companions through measurements of planetary radial velocities, spins, and atmospheric composition. The dominant source of systematic noise for KPIC was fringing or oscillations in the spectrum as a function of wavelength. The fringing signal could dominate residuals by up to 10% of the continuum for high S/N exposures, preventing accurate wavelength calibration, retrieval of atmospheric parameters, and detection of planets with flux ratios less than 1% of the host star. To combat contamination from fringing, we identified its three unique sources and adopted a physically informed model of Fabry\u2013P\u00e9rot cavities to apply to post-processed data. We find that this strategy can effectively model fringing in observations of A0V/F0V stars, reducing the residual systematics caused by fringing by a factor of 2. Beyond modeling the fringing signal, we wedged two of the transmissive optics internal to KPIC to eliminate two of the three sources of fringing and confirmed the third source as the entrance window to the spectrograph NIRSPEC. When applied to new data taken with the wedged optics, our previous model of the Fabry\u2013P\u00e9rot cavity reduced the amplitude of the residuals by a factor of 10.", "doi": "10.1117/1.jatis.11.3.035004", "issn": "2329-4124", "publisher": "SPIE", "publication": "Journal of Astronomical Telescopes, Instruments, and Systems", "publication_date": "2025-08-13", "series_number": "03", "volume": "11", "issue": "03", "pages": "035004" }, { "id": "authors:6kg19-b0c71", "collection": "authors", "collection_id": "6kg19-b0c71", "cite_using_url": "https://authors.library.caltech.edu/records/6kg19-b0c71", "type": "article", "title": "Water Dissociation and Rotational Broadening in the Atmosphere of KELT-20 b from High-resolution Spectroscopy", "author": [ { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Inglis", "given_name": "Julie", "orcid": "0000-0001-9164-7966", "clpid": "Inglis-Julie" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Agrawal", "given_name": "Shubh", "orcid": "0000-0003-2429-5811" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008", "clpid": "Delorme-Jacques-Robert" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Martin", "given_name": "Emily C.", "orcid": "0000-0002-0618-5128" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Venenciano", "given_name": "Taylor", "orcid": "0000-0003-0122-8915" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" } ], "abstract": "

We present atmospheric retrievals from Keck/KPIC Phase II observations of the ultrahot Jupiter (UHJ) KELT-20/MASCARA-2 b. Previous free retrievals of molecular abundances for UHJs have been impacted by significant model biases due to variations in vertical abundance profiles, which we address by including molecular dissociation into our retrieval framework as an additional free parameter. We measure the abundance of CO (logCOMMR=−2.5−0.5+0.6) and obtain a lower limit on the abundance of H2O (logH\u2082OMMR=−1.5_(−1.0)^(+0.8), >−3.0 at 95% confidence) in the atmosphere of KELT-20 b. These abundances yield an atmospheric C/O=0.1_(−0.1)^(+0.4) (C/O < 0.9 at 95% confidence) and suggest a metallicity approximately solar to 10 × solar. H2O is dissociated at pressures below logPH2O=−1.2_(−0.7)^(+0.5) bar, roughly consistent with predictions from chemical equilibrium models, and suggesting that the retrieved composition is not a result of assumptions about the vertical mixing profiles. We also constrain the rotational velocity of KELT-20 b to vsin\u2061i=7.5±0.7 km s−1, suggesting the presence of a jet comparable to the sound speed in the direction of the planet's rotation, assuming the actual rotation of the planet is tidally locked.

", "doi": "10.3847/1538-3881/adce02", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2025-06", "series_number": "6", "volume": "169", "issue": "6", "pages": "333" }, { "id": "authors:p69qb-64r06", "collection": "authors", "collection_id": "p69qb-64r06", "cite_using_url": "https://authors.library.caltech.edu/records/p69qb-64r06", "type": "article", "title": "Implicit electric field conjugation with a photonic lantern nuller", "author": [ { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Lin", "given_name": "Jonathan", "orcid": "0000-0001-8542-3317" }, { "family_name": "Kim", "given_name": "Yoo Jung", "orcid": "0000-0003-1392-0845" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Leon-Saval", "given_name": "Sergio", "orcid": "0000-0002-5606-3874" }, { "family_name": "Amezcua-Correa", "given_name": "Rodrigo", "orcid": "0009-0007-8546-4363" }, { "family_name": "Yerolatsitis", "given_name": "Stephanos", "orcid": "0000-0002-6268-3674" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Gatkine", "given_name": "Pradip", "orcid": "0000-0002-1955-2230", "clpid": "Gatkine-P" }, { "family_name": "Goyal", "given_name": "Suvinay", "clpid": "Goyal-Suvinay" }, { "family_name": "Norris", "given_name": "Barnaby", "orcid": "0000-0002-8352-7515" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Sallum", "given_name": "Steph", "orcid": "0000-0001-6871-6775" } ], "abstract": "

The photonic lantern nuller (PLN) is an instrument concept designed to characterize exoplanets within a single beam width from its host star. The PLN leverages the spatial symmetry of a mode-selective photonic lantern to create nulled ports, which cancel out on-axis starlight but allow off-axis exoplanet light to couple. The null depths are limited by wavefront aberrations in the system as well as by imperfections in the lantern. We show that the implicit electric field conjugation (iEFC) algorithm can be used to reduce the stellar coupling through the PLN by orders of magnitude while maintaining the majority of the off-axis light, leading to deeper null depths (∼10\u207b\u2074) and thus higher sensitivity to potential planet signals. We discuss a theory for the tradeoff we observed among the different ports, where iEFC improves the nulls of some ports at the expense of others, and show that targeting one port alone can lead to deeper starlight rejection through that port than when targeting all ports at once. We also observe different levels of stability depending on the port and discuss the implications of practically implementing this technique for scientific observations.

", "doi": "10.1117/1.jatis.11.2.025004", "issn": "2329-4124", "publisher": "SPIE-Intl Soc Optical Eng", "publication": "Journal of Astronomical Telescopes, Instruments, and Systems", "publication_date": "2025-05", "series_number": "02", "volume": "11", "issue": "02", "pages": "025004" }, { "id": "authors:sx5hp-gz768", "collection": "authors", "collection_id": "sx5hp-gz768", "cite_using_url": "https://authors.library.caltech.edu/records/sx5hp-gz768", "type": "article", "title": "RV Measurements of Directly Imaged Brown Dwarf GQ Lup B to Search for Exosatellites", "author": [ { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Batygin", "given_name": "Konstantin", "orcid": "0000-0002-7094-7908", "clpid": "Batygin-K" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Wang \u738b", "given_name": "Ji \u5409", "orcid": "0000-0002-4361-8885" }, { "family_name": "Blunt", "given_name": "Sarah", "orcid": "0000-0002-3199-2888" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042" }, { "family_name": "Agrawal", "given_name": "Shubh", "orcid": "0000-0003-2429-5811", "clpid": "Agrawal-Shubh" }, { "family_name": "Konopacky", "given_name": "Quinn M.", "orcid": "0000-0002-9936-6285" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Do \u00d3", "given_name": "Clarissa R.", "orcid": "0000-0001-5173-2947" }, { "family_name": "Bartos", "given_name": "Randall" }, { "family_name": "Bond", "given_name": "Charlotte Z." }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008", "clpid": "Delorme-Jacques-Robert" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "L\u00f3pez", "given_name": "Ronald", "orcid": "0000-0002-2019-4995" }, { "family_name": "Martin", "given_name": "Emily C.", "orcid": "0000-0002-0618-5128" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Venenciano", "given_name": "Taylor", "orcid": "0000-0003-0122-8915" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Wizinowich", "given_name": "Peter", "orcid": "0000-0002-1646-442X" } ], "abstract": "

GQ Lup B is one of the few substellar companions with a detected cicumplanetary disk (CPD). Observations of the CPD suggest the presence of a cavity, possibly formed by an exosatellite. Using the Keck Planet Imager and Characterizer (KPIC), a high-contrast imaging suite that feeds a high-resolution spectrograph (1.9–2.5 µm, R∼35,000), we present the first dedicated radial velocity (RV) observations around a high-contrast, directly imaged substellar companion, GQ Lup B, to search for exosatellites. Over 11 epochs, we find a best and median RV error of 400–1000 m s\u207b¹, most likely limited by systematic fringing in the spectra due to transmissive optics within KPIC. With this RV precision, KPIC is sensitive to exomoons 0.6%–2.8% the mass of GQ Lup B (∼30 M_(Jup)) at separations between the Roche limit and 65 R_(Jup), or the extent of the cavity inferred within the CPD detected around GQ Lup B. Using simulations of HISPEC, a high resolution infrared spectrograph planned to debut at W.M. Keck Observatory in 2026, we estimate future exomoon sensitivity to increase by over an order of magnitude, providing sensitivity to less massive satellites potentially formed within the CPD itself. Additionally, we run simulations to estimate the amount of material that different masses of satellites could clear in a CPD to create the observed cavity. We find satellite-to-planet mass ratios of q > 2 × 10\u207b\u2074 can create observable cavities and report a maximum cavity size of ∼51 R_(Jup) carved from a satellite.

", "doi": "10.3847/1538-3881/ad73d8", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2024-09-25", "series_number": "4", "volume": "168", "issue": "4", "pages": "175" }, { "id": "authors:cwq75-y7n72", "collection": "authors", "collection_id": "cwq75-y7n72", "cite_using_url": "https://authors.library.caltech.edu/records/cwq75-y7n72", "type": "article", "title": "Atmospheric Characterization of the Super-Jupiter HIP 99770 b with KPIC", "author": [ { "family_name": "Zhang", "given_name": "Yapeng", "orcid": "0000-0003-0097-4414", "clpid": "Zhang-Yapeng" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Wang", "given_name": "Jason J.", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Ruffio", "given_name": "Jean-Bapiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Knutson", "given_name": "Heather A.", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Inglis", "given_name": "Julie", "orcid": "0000-0001-9164-7966", "clpid": "Inglis-Julie" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Chachan", "given_name": "Yayaati", "orcid": "0000-0003-1728-8269" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wang", "given_name": "Ji", "orcid": "0000-0002-4361-8885" }, { "family_name": "Do \u00d3", "given_name": "Clarissa R.", "orcid": "0000-0001-5173-2947" } ], "abstract": "

Young, self-luminous super-Jovian companions discovered by direct imaging provide a challenging test for planet formation and evolution theories. By spectroscopically characterizing the atmospheric compositions of these super-Jupiters, we can constrain their formation histories. Here we present studies of the recently discovered HIP 99770 b, a 16 M Jup high-contrast companion on a 17 au orbit, using the fiber-fed high-resolution spectrograph KPIC ( R ∼ 35,000) on the Keck II telescope. Our K-band observations led to detections of H2O and CO in the atmosphere of HIP 99770 b. We carried out free retrieval analyses using petitRADTRANS to measure its chemical abundances, including the metallicity and C/O ratio, projected rotation velocity ( v sin i ), and radial velocity (RV). We found that the companion's atmosphere has C/O = 0.55 − 0.04 + 0.06 and [M/H] = 0.26 − 0.23 + 0.24 (1σ confidence intervals), values consistent with those of the Sun and with a companion formation via gravitational instability or core accretion. The projected rotation velocity v sin ( i ) < 7.8 km s\u207b¹ is small relative to other directly imaged companions with similar masses and ages. This may imply a nearly pole-on orientation or effective magnetic braking by a circumplanetary disk. In addition, we added the companion-to-primary relative RV measurement to the orbital fitting and obtained updated constraints on orbital parameters. Detailed characterization of super-Jovian companions within 20 au like HIP 99770 b is critical for understanding the formation histories of this population.

", "doi": "10.3847/1538-3881/ad6609", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2024-09", "series_number": "3", "volume": "168", "issue": "3", "pages": "131" }, { "id": "authors:h5z2c-86g12", "collection": "authors", "collection_id": "h5z2c-86g12", "cite_using_url": "https://authors.library.caltech.edu/records/h5z2c-86g12", "type": "article", "title": "Are These Planets or Brown Dwarfs? Broadly Solar Compositions from High-resolution Atmospheric Retrievals of \u223c10\u201330 M_(Jup) Companions", "author": [ { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Wang", "given_name": "Jason", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Zhang", "given_name": "Yapeng", "orcid": "0000-0003-0097-4414", "clpid": "Zhang-Yapeng" }, { "family_name": "Knutson", "given_name": "Heather", "orcid": "0000-0002-5375-4725", "clpid": "Knutson-H-A" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Mamajek", "given_name": "Eric E.", "orcid": "0000-0003-2008-1488", "clpid": "Mamajek-Eric-E" }, { "family_name": "Inglis", "given_name": "Julie", "orcid": "0000-0001-9164-7966", "clpid": "Inglis-Julie" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Bryan", "given_name": "Marta L.", "orcid": "0000-0002-6076-5967" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Molli\u00e8re", "given_name": "Paul", "orcid": "0000-0003-4096-7067" }, { "family_name": "Hejazi", "given_name": "Neda", "orcid": "0000-0001-5541-6087" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wang", "given_name": "Ji", "orcid": "0000-0002-4361-8885" }, { "family_name": "Agrawal", "given_name": "Shubh", "orcid": "0000-0003-2429-5811" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" } ], "abstract": "

Using Keck Planet Imager and Characterizer high-resolution (R ∼ 35,000) spectroscopy from 2.29 to 2.49 μm, we present uniform atmospheric retrievals for eight young substellar companions with masses of ∼10–30 MJup, orbital separations spanning ∼50–360 au, and Teff between ∼1500 and 2600 K. We find that all companions have solar C/O ratios and metallicities to within the 1σ–2σ level, with the measurements clustered around solar composition. Stars in the same stellar associations as our systems have near-solar abundances, so these results indicate that this population of companions is consistent with formation via direct gravitational collapse. Alternatively, core accretion outside the CO snowline would be compatible with our measurements, though the high mass ratios of most systems would require rapid core assembly and gas accretion in massive disks. On a population level, our findings can be contrasted with abundance measurements for directly imaged planets with m < 10 MJup, which show tentative atmospheric metal enrichment compared to their host stars. In addition, the atmospheric compositions of our sample of companions are distinct from those of hot Jupiters, which most likely form via core accretion. For two companions with Teff ∼ 1700–2000 K (κ And b and GSC 6214–210 b), our best-fit models prefer a nongray cloud model with >3σ significance. The cloudy models yield 2σ−3σ lower Teff for these companions, though the C/O and [C/H] still agree between cloudy and clear models at the 1σ level. Finally, we constrain 12CO/13CO for three companions with the highest signal-to-noise ratio data (GQ Lup b, HIP 79098b, and DH Tau b) and report 

", "doi": "10.3847/1538-4357/ad4796", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2024-07-20", "series_number": "1", "volume": "970", "issue": "1", "pages": "71" }, { "id": "authors:j1rga-5hk42", "collection": "authors", "collection_id": "j1rga-5hk42", "cite_using_url": "https://authors.library.caltech.edu/records/j1rga-5hk42", "type": "article", "title": "Atmospheric Metallicity and C/O of HD 189733 b from High-resolution Spectroscopy", "author": [ { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768", "clpid": "Finnerty-Luke" }, { "family_name": "Xuan", "given_name": "Jerry W.", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Agrawal", "given_name": "Shubh", "orcid": "0000-0003-2429-5811" }, { "family_name": "Baker", "given_name": "Ashley", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Blake", "given_name": "Geoffrey A.", "orcid": "0000-0003-0787-1610", "clpid": "Blake-G-A" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486", "clpid": "Calvin-Benjamin" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008", "clpid": "Delorme-Jacques-Robert" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Martin", "given_name": "Emily C.", "orcid": "0000-0002-0618-5128" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Morris", "given_name": "Evan" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Skemer", "given_name": "Andrew", "orcid": "0000-0001-6098-3924" }, { "family_name": "Venenciano", "given_name": "Taylor", "orcid": "0000-0003-0122-8915" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wallack", "given_name": "Nicole L.", "orcid": "0000-0003-0354-0187", "clpid": "Wallack-N-L" }, { "family_name": "Wang \u738b", "given_name": "Jason J. \u52b2\u98de", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Wang \u5409", "given_name": "Ji \u738b", "orcid": "0000-0002-4361-8885" } ], "abstract": "

We present high-resolution K-band emission spectra of the quintessential hot Jupiter HD 189733 b from the Keck Planet Imager and Characterizer. Using a Bayesian retrieval framework, we fit the dayside pressure–temperature profile, orbital kinematics, mass-mixing ratios of H2O, CO, CH4, NH3, HCN, and H2S, and the 13CO/12CO ratio. We measure mass fractions of logH\u2082O = −2.0_(−0.4)^(+0.4) and log CO= −2.2_(−0.5)^(+0.5), and place upper limits on the remaining species. Notably, we find logCH4 < −4.5 at 99% confidence, despite its anticipated presence at the equilibrium temperature of HD 189733 b assuming local thermal equilibrium. We make a tentative (∼3σ) detection of 13CO, and the retrieved posteriors suggest a 12C/13C ratio similar to or substantially less than the local interstellar value. The possible 13C enrichment would be consistent with accretion of fractionated material in ices or in the protoplanetary disk midplane. The retrieved abundances correspond to a substantially substellar atmospheric C/O = 0.3 ± 0.1, while the carbon and oxygen abundances are stellar to slightly superstellar, consistent with core-accretion models which predict an inverse correlation between C/O and metallicity. The specific combination of low C/O and high metallicity suggests significant accretion of solid material may have occurred late in the formation process of HD 189733 b.

", "doi": "10.3847/1538-3881/ad1180", "issn": "0004-6256", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2024-01", "series_number": "1", "volume": "167", "issue": "1", "pages": "43" }, { "id": "authors:1vsmk-z3045", "collection": "authors", "collection_id": "1vsmk-z3045", "cite_using_url": "https://authors.library.caltech.edu/records/1vsmk-z3045", "type": "article", "title": "Vortex fiber nulling for exoplanet observations: implementation and first light", "author": [ { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Xuan", "given_name": "Jerry", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "orcid": "0000-0001-8953-1008" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Mennesson", "given_name": "Bertrand", "orcid": "0000-0003-4205-4800", "clpid": "Mennesson-Bertrand" }, { "family_name": "Serabyn", "given_name": "Eugene", "orcid": "0009-0009-2491-0694", "clpid": "Serabyn-Eugene" }, { "family_name": "Wallace", "given_name": "J. Kent", "orcid": "0000-0001-5299-6899", "clpid": "Wallace-J-Kent" }, { "family_name": "Wang", "given_name": "Jason", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason-J" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Finnerty", "given_name": "Luke", "orcid": "0000-0002-1392-0768" }, { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Millar-Blanchaer", "given_name": "Maxwell", "orcid": "0000-0001-6205-9233", "clpid": "Millar-Blanchaer-M-A" }, { "family_name": "Baker", "given_name": "Ashley", "orcid": "0000-0002-6525-7013", "clpid": "Baker-Ashley" }, { "family_name": "Bartos", "given_name": "Randall", "clpid": "Bartos-Randall" }, { "family_name": "Calvin", "given_name": "Benjamin", "orcid": "0000-0003-4737-5486" }, { "family_name": "Cetre", "given_name": "Sylvain" }, { "family_name": "Doppmann", "given_name": "Greg" }, { "family_name": "Fitzgerald", "given_name": "Michael P.", "orcid": "0000-0002-0176-8973" }, { "family_name": "Hillman", "given_name": "Sofia" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "Lopez", "given_name": "Ronald", "orcid": "0000-0002-2019-4995" }, { "family_name": "Morris", "given_name": "Evan", "orcid": "0000-0003-3165-0922" }, { "family_name": "Pezzato", "given_name": "Jacklyn", "clpid": "Pezzato-Jacklyn" }, { "family_name": "Phillips", "given_name": "Caprice L.", "orcid": "0000-0001-5610-5328" }, { "family_name": "Ren", "given_name": "Bin B.", "orcid": "0000-0003-1698-9696", "clpid": "Ren-Bin" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" }, { "family_name": "Schofield", "given_name": "Tobias", "clpid": "Schofield-Tobias" }, { "family_name": "Skemer", "given_name": "Andrew J.", "orcid": "0000-0001-6098-3924" }, { "family_name": "Vancil", "given_name": "Connor" }, { "family_name": "Wang", "given_name": "Ji" } ], "abstract": "

Vortex fiber nulling (VFN) is a single-aperture interferometric technique for detecting and characterizing exoplanets separated from their host star by less than a diffracted beam width. VFN uses a vortex mask and single-mode fiber to selectively reject starlight while coupling off-axis planet light with a simple optical design that can be readily implemented on existing direct imaging instruments that can feed light to an optical fiber. With its axially symmetric coupling region peaking within the inner working angle of conventional coronagraphs, VFN is more efficient at detecting new companions at small separations than conventional direct imaging, thereby increasing the yield of on-going exoplanet search campaigns. We deployed a VFN mode operating in K band (2.0 to 2.5 μm) on the Keck Planet Imager and Characterizer (KPIC) instrument at the Keck II Telescope. We present the instrument design of this first on-sky demonstration of VFN and the results from on-sky commissioning, including planet and star throughput measurements and predicted flux-ratio detection limits for close-in companions. The instrument performance is shown to be sufficient for detecting a companion 103 times fainter than a fifth magnitude host star in 1 h at a separation of 50 mas (1.1 λ / D). This makes the instrument capable of efficiently detecting substellar companions around young stars. We also discuss several routes for improvement that will reduce the required integration time for a detection by a factor >3.

", "doi": "10.1117/1.jatis.9.3.035002", "issn": "2329-4124", "publisher": "SPIE-Intl Soc Optical Eng", "publication": "Journal of Astronomical Telescopes, Instruments, and Systems", "publication_date": "2023-09", "series_number": "03", "volume": "9", "issue": "03", "pages": "035002" }, { "id": "authors:tevq8-ae181", "collection": "authors", "collection_id": "tevq8-ae181", "cite_using_url": "https://authors.library.caltech.edu/records/tevq8-ae181", "type": "article", "title": "On-sky speckle nulling through a single-mode fiber with the Keck Planet Imager and Characterizer", "author": [ { "family_name": "Xin", "given_name": "Yinzi", "orcid": "0000-0002-6171-9081", "clpid": "Xin-Yinzi" }, { "family_name": "Xuan", "given_name": "Jerry", "orcid": "0000-0002-6618-1137", "clpid": "Xuan-Jerry-W" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Wang", "given_name": "Jason", "orcid": "0000-0003-0774-6502", "clpid": "Wang-Jason" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Do \u00d3", "given_name": "Clarissa", "orcid": "0000-0001-5173-2947" }, { "family_name": "Fitzgerald", "given_name": "Michael", "orcid": "0000-0002-0176-8973" }, { "family_name": "Horstman", "given_name": "Katelyn", "orcid": "0000-0001-9708-8667", "clpid": "Horstman-Katelyn" }, { "family_name": "Hsu", "given_name": "Chih-Chun", "orcid": "0000-0002-5370-7494" }, { "family_name": "Liberman", "given_name": "Joshua", "orcid": "0000-0002-4934-3042", "clpid": "Liberman-Joshua" }, { "family_name": "L\u00f3pez", "given_name": "Ronald A.", "orcid": "0000-0002-2019-4995" }, { "family_name": "Phillips", "given_name": "Caprice L.", "orcid": "0000-0001-5610-5328" }, { "family_name": "Ren", "given_name": "Bin B.", "orcid": "0000-0003-1698-9696", "clpid": "Ren-Bin" }, { "family_name": "Ruffio", "given_name": "Jean-Baptiste", "orcid": "0000-0003-2233-4821", "clpid": "Ruffio-J-B" }, { "family_name": "Sappey", "given_name": "Ben", "orcid": "0000-0003-1399-3593" } ], "abstract": "The Keck Planet Imager and Characterizer (KPIC) is an instrument at the Keck II telescope that enables high-resolution spectroscopy of directly imaged exoplanets and substellar companions. KPIC uses single-mode fibers to couple the adaptive optics system to Keck's near-infrared spectrometer (NIRSPEC). However, KPIC's sensitivity at small separations is limited by the leakage of stellar light into the fiber. Speckle nulling uses a deformable mirror (DM) to destructively interfere starlight with itself, a technique typically used to reduce stellar signal on a focal-plane imaging detector. We present the first on-sky demonstration of speckle nulling through an optical fiber with KPIC, using NIRSPEC to collect exposures that measure speckle phase for quasi-real-time wavefront control while also serving as science data. We repeat iterations of measurement and correction, each using at least five exposures (four with DM probes to determine phase and one unprobed exposure to measure the intensity) and taking about 6 min when using 59.0 s exposures, including NIRSPEC overheads. We show a decrease in the on-sky leaked starlight by a factor of 2.6 to 2.8 in the targeted spectral order, at a spatial separation of 2.0 \u03bb / D in K-band. This corresponds to an estimated factor of 2.6 to 2.8 decrease in the required exposure time to reach a given signal-to-noise ratio, relative to conventional KPIC observations. The performance of speckle nulling is limited by instability in the speckle phase: when the loop is opened, the null-depth degrades by a factor of 2 on the timescale of a single phase measurement, which would limit the suppression that can be achieved. Future work includes exploring gradient-descent methods, which may be faster and thereby able to achieve deeper nulls. In the meantime, the speckle nulling algorithm demonstrated in this work can be used to decrease stellar leakage and improve the signal-to-noise of science observations.", "doi": "10.1117/1.jatis.9.3.035001", "issn": "2329-4124", "publisher": "SPIE-Intl Soc Optical Eng", "publication": "Journal of Astronomical Telescopes, Instruments, and Systems", "publication_date": "2023-08", "series_number": "03", "volume": "9", "issue": "03", "pages": "035001" }, { "id": "authors:kb2sq-8w336", "collection": "authors", "collection_id": "kb2sq-8w336", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201014-111856081", "type": "article", "title": "Microelectromechanical deformable mirror development for high-contrast imaging, part 2: the impact of quantization errors on coronagraph image contrast", "author": [ { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Bendek", "given_name": "Eduardo", "orcid": "0000-0002-9408-8925", "clpid": "Bendek-E-A" }, { "family_name": "Kern", "given_name": "Brian D.", "clpid": "Kern-B-D" }, { "family_name": "Marx", "given_name": "David", "clpid": "Marx-David-S" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Prada", "given_name": "Camilo M.", "clpid": "Prada-C-M" }, { "family_name": "Riggs", "given_name": "A. J. Eldorado", "orcid": "0000-0002-0863-6228", "clpid": "Riggs-A-J-E" }, { "family_name": "Seo", "given_name": "Byoung-Joon", "clpid": "Seo-Byoung-Joon" }, { "family_name": "Serabyn", "given_name": "Eugene", "clpid": "Serabyn-E" }, { "family_name": "Shaklan", "given_name": "Stuart", "clpid": "Shaklan-S-B" } ], "abstract": "Stellar coronagraphs rely on deformable mirrors (DMs) to correct wavefront errors and create high-contrast images. Imperfect control of the DM limits the achievable contrast, and therefore, the DM control electronics must provide fine surface height resolution and low noise. We study the impact of quantization errors due to the DM electronics on the image contrast using experimental data from the High Contrast Imaging Testbed facility at NASA's Jet Propulsion Laboratory. We find that the simplest analytical model gives optimistic predictions compared to real cases, with contrast up to 3 times better, which leads to DM surface height resolution requirements that are incorrectly relaxed by 70%. We show that taking into account the DM actuator shape, or influence function, improves the analytical predictions. However, we also find that end-to-end numerical simulations of the wavefront sensing and control process provide the most accurate predictions and recommend such an approach for setting robust requirements on the DM control electronics. From our experimental and numerical results, we conclude that a surface height resolution of \u223c6\u2009\u2009pm is required for imaging temperate terrestrial exoplanets around solar-type stars at wavelengths as small as 450 nm with coronagraph instruments on future space telescopes. Finally, we list the recognizable characteristics of quantization errors that may help determine if they are a limiting factor.", "doi": "10.1117/1.jatis.6.4.045002", "issn": "2329-4124", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "publication": "Journal of Astronomical Telescopes, Instruments, and Systems", "publication_date": "2020-10", "series_number": "4", "volume": "6", "issue": "4", "pages": "Art. No. 045002" }, { "id": "authors:3anw2-1zr92", "collection": "authors", "collection_id": "3anw2-1zr92", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-092720940", "type": "article", "title": "High-contrast Demonstration of an Apodized Vortex Coronagraph", "author": [ { "family_name": "Llop-Sayson", "given_name": "Jorge", "clpid": "Llop-Sayson-J-D" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "clpid": "Jovanovic-N" }, { "family_name": "Coker", "given_name": "Carl T.", "orcid": "0000-0002-9954-7887", "clpid": "Coker-C-T" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "clpid": "Delorme-J-R" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Fucik", "given_name": "Jason", "clpid": "Fucik-J-R" }, { "family_name": "Riggs", "given_name": "A. J. Eldorado", "orcid": "0000-0002-0863-6228", "clpid": "Riggs-A-J-E" }, { "family_name": "Wallace", "given_name": "J. Kent", "clpid": "Wallace-J-K" } ], "abstract": "High-contrast imaging is the primary path to the direct detection and characterization of Earth-like planets around solar-type stars; a cleverly designed internal coronagraph suppresses the light from the star, revealing the elusive circumstellar companions. However, future large-aperture telescopes (>4 m in diameter) will likely have segmented primary mirrors, which cause additional diffraction of unwanted stellar light. Here we present the first high-contrast laboratory demonstration of an apodized vortex coronagraph, in which an apodizer is placed upstream of a vortex focal plane mask to improve its performance with a segmented aperture. The gray-scale apodization is numerically optimized to yield a better sensitivity to faint companions assuming an aperture shape similar to the LUVOIR-B concept. Using wavefront sensing and control over a one-sided dark hole, we achieve a raw contrast of 2 \u00d7 10\u207b\u2078 in monochromatic light at 775 nm, and a raw contrast of 4 \u00d7 10\u207b\u2078 in a 10% bandwidth. These results open the path to a new family of coronagraph designs, optimally suited for next-generation segmented space telescopes.", "doi": "10.3847/1538-3881/ab6329", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2020-03", "series_number": "3", "volume": "159", "issue": "3", "pages": "Art. No. 79" }, { "id": "authors:6c6v7-cck54", "collection": "authors", "collection_id": "6c6v7-cck54", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181130-143911660", "type": "article", "title": "Vortex fiber nulling for exoplanet observations. I. Experimental demonstration in monochromatic light", "author": [ { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "clpid": "Jovanovic-N" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Levraud", "given_name": "Nicolas", "clpid": "Levraud-N" } ], "abstract": "Vortex fiber nulling is a method for spectroscopically characterizing exoplanets at small angular separations, \u2272", "doi": "10.1364/OL.44.002204", "issn": "0146-9592", "publisher": "Optical Society of America", "publication": "Optics Letters", "publication_date": "2019-05-01", "series_number": "9", "volume": "44", "issue": "9", "pages": "2204-2207" }, { "id": "authors:fhrsk-yh704", "collection": "authors", "collection_id": "fhrsk-yh704", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190402-160051415", "type": "article", "title": "Demonstration of an electric field conjugation algorithm for improved starlight rejection through a single mode optical fiber", "author": [ { "family_name": "Llop Sayson", "given_name": "Jorge", "clpid": "Llop-Sayson-J-D" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Jovanovic", "given_name": "Nemanja", "orcid": "0000-0001-5213-6207", "clpid": "Jovanovic-N" }, { "family_name": "Calvin", "given_name": "Benjamin", "clpid": "Calvin-B-A" }, { "family_name": "Levraud", "given_name": "Nicolas", "clpid": "Levraud-N" }, { "family_name": "Roberson", "given_name": "Milan", "clpid": "Roberson-M" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "clpid": "Delorme-J-R" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Klimovich", "given_name": "Nikita", "clpid": "Klimovich-N-S" }, { "family_name": "Xin", "given_name": "Yeyuan", "clpid": "Xin-Yeyuan" } ], "abstract": "Linking a coronagraph instrument to a spectrograph via a single-mode optical fiber is a pathway toward detailed characterization of exoplanet atmospheres with current and future ground- and space-based telescopes. However, given the extreme brightness ratio and small angular separation between planets and their host stars, the planet signal-to-noise ratio will likely be limited by the unwanted coupling of starlight into the fiber. To address this issue, we utilize a wavefront control loop and a deformable mirror to systematically reject starlight from the fiber by measuring what is transmitted through the fiber. The wavefront control algorithm is based on the formalism of electric field conjugation (EFC), which in our case accounts for the spatial mode selectivity of the fiber. This is achieved by using a control output that is the overlap integral of the electric field with the fundamental mode of a single-mode fiber. This quantity can be estimated by pairwise image plane probes injected using a deformable mirror. We present simulation and laboratory results that demonstrate our approach offers a significant improvement in starlight suppression through the fiber relative to a conventional EFC controller. With our experimental setup, which provides an initial normalized intensity of 3\u2009\u2009\u00d7\u2009\u200910\u2009\u2009\u2212\u2009\u20094 in the fiber at an angular separation of 4\u03bb\u2009\u2009/\u2009\u2009D, we obtain a final normalized intensity of 3\u2009\u2009\u00d7\u2009\u200910\u2009\u2009\u2212\u2009\u20096 in monochromatic light at \u03bb\u2009\u2009=\u2009\u2009635\u2009\u2009nm through the fiber (100\u2009\u2009\u00d7\u2009\u2009 suppression factor) and 2\u2009\u2009\u00d7\u2009\u200910\u2009\u2009\u2212\u2009\u20095 in \u0394\u03bb\u2009\u2009/\u2009\u2009\u03bb\u2009\u2009=\u2009\u20098\u2009\u2009%\u2009\u2009 broadband light about \u03bb\u2009\u2009=\u2009\u2009625\u2009\u2009nm (10\u2009\u2009\u00d7\u2009\u2009 suppression factor). The fiber-based approach improves the sensitivity of spectral measurements at high contrast and may serve as an integral part of future space-based exoplanet imaging missions as well as ground-based instruments.", "doi": "10.1117/1.jatis.5.1.019004", "issn": "2329-4124", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "publication": "Journal of Astronomical Telescopes, Instruments, and Systems", "publication_date": "2019-01", "series_number": "1", "volume": "5", "issue": "1", "pages": "Art. No. 019004" }, { "id": "authors:pg1v3-qgj08", "collection": "authors", "collection_id": "pg1v3-qgj08", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170330-075341818", "type": "article", "title": "Observing Exoplanets with High-Dispersion Coronagraphy. II. Demonstration of an Active Single-Mode Fiber Injection Unit", "author": [ { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Ruane", "given_name": "Garreth", "orcid": "0000-0003-4769-1665", "clpid": "Ruane-G-J" }, { "family_name": "Xuan", "given_name": "Wenhao", "clpid": "Xuan-Wenhao" }, { "family_name": "Echeverri", "given_name": "Daniel", "orcid": "0000-0002-1583-2040", "clpid": "Echeverri-D" }, { "family_name": "Klimovich", "given_name": "Nikita S.", "clpid": "Klimovich-N-S" }, { "family_name": "Randolph", "given_name": "Michael", "clpid": "Randolph-M" }, { "family_name": "Fucik", "given_name": "Jason", "clpid": "Fucik-J-R" }, { "family_name": "Wallace", "given_name": "James K.", "clpid": "Wallace-J-K" }, { "family_name": "Wang", "given_name": "Ji", "orcid": "0000-0002-4361-8885", "clpid": "Wang-Ji" }, { "family_name": "Vasisht", "given_name": "Gautam", "orcid": "0000-0002-1871-6264", "clpid": "Vasisht-G" }, { "family_name": "Dekany", "given_name": "Richard", "clpid": "Dekany-Richard" }, { "family_name": "Mennesson", "given_name": "Bertrand", "orcid": "0000-0003-4205-4800", "clpid": "Mennesson-B" }, { "family_name": "Choquet", "given_name": "\u00c9lodie", "orcid": "0000-0002-9173-0740", "clpid": "Choquet-\u00c9lodie" }, { "family_name": "Delorme", "given_name": "Jacques-Robert", "clpid": "Delorme-J-R" }, { "family_name": "Serabyn", "given_name": "Eugene", "clpid": "Serabyn-E" } ], "abstract": "High-dispersion coronagraphy (HDC) optimally combines high contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway towards fully characterizing exoplanet atmospheres across a broad range of masses from giant gaseous planets down to Earth-like planets. In addition to determining the molecular composition of exoplanet atmospheres, HDC also enables Doppler mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as precise measurements of exoplanet rotational velocities. Here, we demonstrate an innovative concept for injecting the directly-imaged planet light into a single-mode fiber, linking a high-contrast adaptively-corrected coronagraph to a high-resolution spectrograph (diffraction-limited or not). Our laboratory demonstration includes three key milestones: close-to-theoretical injection efficiency, accurate pointing and tracking, on-fiber coherent modulation and speckle nulling of spurious starlight signal coupling into the fiber. Using the extreme modal selectivity of single-mode fibers, we also demonstrated speckle suppression gains that outperform conventional image-based speckle nulling by at least two orders of magnitude.", "doi": "10.3847/1538-4357/aa647f", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2017-04-01", "series_number": "2", "volume": "838", "issue": "2", "pages": "Art. No. 92" } ]