activity
19982026
most citedDiscovery and spectroscopy of the young Jovian planet 51 Eri b with the Gemini Planet Imager

559 citations · 703 across the 25 of their papers we have counts for

collaborators

26 papers

astro-ph.EP2026

Atmospheric characterization of six ultra-hot Jupiters from -band high-resolution spectroscopy

Luke Finnerty, Michael P. Fitzgerald, Yinzi Xin +27

We present new Keck/KPIC high-resolution spectroscopic detections of three ultra-hot Jupiters (UHJs) in the band: WASP-189b (), MASCARA-1b (), and…

astro-ph.EP2025

Chemical and Isotopic Homogeneity Between the L Dwarf CD-35 2722 B and its Early M Host Star

Gavin Wang, Jerry Xuan, Darío Picos +29

CD-35 2722 B is an L dwarf companion to the nearby, Myr old M1 dwarf CD-35 2722 A. We present a detailed analysis of both objects using high-resolution ($R \sim 35,00…

astro-ph.EP2025★ 3 cited

Dynamical Architectures of S-type Transiting Planets in Binaries II: A Dichotomy in Orbital Alignment of Small Planets in Close Binary Systems

Jingwen Zhang, Daniel Huber, Michael Bottom +35

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…

astro-ph.EP2025

The watery atmosphere of HD~209458~b revealed by joint - and -band high-resolution spectroscopy

Luke Finnerty, Julie Inglis, Michael P. Fitzgerald +26

We present a joint analysis of high-resolution - and -band observations of the benchmark hot Jupiter \hdb\ from the Keck Planet Imager and Characterizer (KPIC). One half nigh…

astro-ph.EP2025

Water dissociation and rotational broadening in the atmosphere of KELT-20 b from high-resolution spectroscopy

Luke Finnerty, Yinzi Xin, Jerry W. Xuan +29

We present atmospheric retrievals from Keck/KPIC phase II observations of the ultra-hot Jupiter KELT-20/MASCARA-2~b. Previous free retrievals of molecular abundances for ultra-hot…

astro-ph.EP2025

HD 206893 B at High Spectral Resolution with the Keck Planet Imager and Characterizer (KPIC)

Ben Sappey, Quinn Konopacky, Clarissa R. Do O +38

We present an atmospheric characterization and orbital analysis of HD 206893 B, an exceptionally red, L/T-transition substellar companion in a multiplanetary system, via Keck Plane…

astro-ph.EP2024★ 8 cited

PDS 70b Shows Stellar-like Carbon-to-oxygen Ratio

Chih-Chun Hsu, Jason J. Wang, Geoffrey A. Blake +27

The 5 Myr PDS 70 is the only known system with protoplanets residing in the cavity of the circumstellar disk from which they formed, ideal for studying exoplanet formation an…

astro-ph.EP2024

True mass and atmospheric composition of the non-transiting hot Jupiter HD 143105 b

Luke Finnerty, Yinzi Xin, Jerry W. Xuan +28

We present Keck/KPIC phase II -band observations of the non-transiting hot Jupiter HD 143105 b. Using a cross-correlation approach, we make the first detection of the planetary…

astro-ph.EP2024

RV measurements of directly imaged brown dwarf GQ Lup B to search for exo-satellites

Katelyn Horstman, Jean-Baptiste Ruffio, Konstantin Batygin +35

GQ Lup B is one of the few substellar companions with a detected cicumplanetary disk, or CPD. Observations of the CPD suggest the presence of a cavity, possibly formed by an exo-sa…

astro-ph.EP2024★ 15 cited

Atmospheric characterization of the super-Jupiter HIP 99770 b with KPIC

Yapeng Zhang, Jerry W. Xuan, Dimitri Mawet +28

Young, self-luminous super-Jovian companions discovered by direct imaging provide a challenging test of planet formation and evolution theories. By spectroscopically characterizing…

astro-ph.IM2024

Towards understanding interactions between the AO system and segment co-phasing with the vector-Zernike wavefront sensor on Keck

Maïssa Salama, Charlotte Guthery, Vincent Chambouleyron +14

We extend our previous demonstration of the first on-sky primary mirror segment closed-loop control on Keck using a vector-Zernike wavefront sensor (vZWFS), which improved the Stre…

astro-ph.IM2024

The high-contrast performance of the Keck Planet Imager and Characterizer

Jason J. Wang, Dimitri Mawet, Jerry W. Xuan +25

The Keck Planet Imager and Characterizer (KPIC), a series of upgrades to the Keck II Adaptive Optics System and Instrument Suite, aims to demonstrate high-resolution spectroscopy o…

astro-ph.SR2024★ 18 cited

Rotation and Abundances of the Benchmark Brown Dwarf HD 33632 Ab from Keck/KPIC High-resolution Spectroscopy

Chih-Chun Hsu, Jason J. Wang, Jerry W. Xuan +24

We present the projected rotational velocity and molecular abundances for HD 33632 Ab obtained via Keck Planet Imager and Characterizer high-resolution spectroscopy. HD 33632 Ab is…

astro-ph.EP2024★ 2 cited

Are these planets or brown dwarfs? Broadly solar compositions from high-resolution atmospheric retrievals of ~10-30 companions

Jerry W. Xuan, Chih-Chun Hsu, Luke Finnerty +32

Using Keck Planet Imager and Characterizer (KPIC) high-resolution (~35000) spectroscopy from 2.29-2.49 m, we present uniform atmospheric retrievals for eight young substellar…

astro-ph.EP2024

kappa And b is a fast rotator from KPIC High Resolution Spectroscopy

Evan C. Morris, Jason J. Wang, Chih-Chun Hsu +24

We used the Keck Planet Imager and Characterizer (KPIC) to obtain high-resolution (R35,000) K-band spectra of kappa Andromedae b, a planetary-mass companion orbiting the B9V…

astro-ph.IM2024

Keck Primary Mirror Closed-Loop Segment Control using a Vector-Zernike Wavefront Sensor

Maissa Salama, Charlotte Guthery, Vincent Chambouleyron +17

We present the first on-sky segmented primary mirror closed-loop piston control using a Zernike wavefront sensor (ZWFS) installed on the Keck II telescope. Segment co-phasing error…

astro-ph.SR2024

Orbital and Atmospheric Characterization of the 1RXS J034231.8+121622 System Using High-Resolution Spectroscopy Confirms That The Companion is a Low-Mass Star

Clarissa R. Do Ó, Ben Sappey, Quinn M. Konopacky +33

The 1RXS J034231.8+121622 system consists of an M dwarf primary and a directly imaged low-mass stellar companion. We use high resolution spectroscopic data from Keck/KPIC to estima…

astro-ph.IM2024

Efficient ultra-broadband low-resolution astrophotonic spectrographs

Pradip Gatkine, Greg Sercel, Nemanja Jovanovic +9

Broadband low-resolution near-infrared spectrographs in a compact form are crucial for ground- and space-based astronomy and other fields of sensing. Astronomical spectroscopy pose…

astro-ph.IM2024

Thermal control of long delay lines in a high-resolution astrophotonic spectrograph

Gregory P. Sercel, Pradip R. Gatkine, Nemanja Jovanovic +4

High-resolution astronomical spectroscopy carried out with a photonic Fourier transform spectrograph (FTS) requires long asymmetrical optical delay lines that can be dynamically tu…

astro-ph.EP2024

Vortex Fiber Nulling for Exoplanet Observations: First Direct Detection of M Dwarf Companions around HIP 21543, HIP 94666, and HIP 50319

Daniel Echeverri, Jerry W. Xuan, John D. Monnier +35

Vortex fiber nulling (VFN) is a technique for detecting and characterizing faint companions at small separations from their host star. A near-infrared (m) VFN demonstrat…

astro-ph.SR2023★ 3 cited

Validation of elemental and isotopic abundances in late-M spectral types with the benchmark HIP 55507 AB system

Jerry W. Xuan, Jason J. Wang, Luke Finnerty +48

M dwarfs are common host stars to exoplanets but often lack atmospheric abundance measurements. Late-M dwarfs are also good analogs to the youngest substellar companions, which sha…

astro-ph.IM2023

The path to detecting extraterrestrial life with astrophotonics

Nemanja Jovanovic, Yinzi Xin, Michael P. Fitzgerald +20

Astrophysical research into exoplanets has delivered thousands of confirmed planets orbiting distant stars. These planets span a wide ranges of size and composition, with diversity…

astro-ph.IM2022★ 1 cited

On-sky reconstruction of Keck Primary Mirror Piston Offsets using a Zernike Wavefront Sensor

Maaike A. M. van Kooten, Sam Ragland, Rebecca Jensen-Clem +3

The next generation of large ground- and space-based optical telescopes will have segmented primary mirrors. Co-phasing the segments requires a sensitive wavefront sensor capable o…

astro-ph.EP2019★ 20 cited

First Resolved Scattered-Light Images of Four Debris Disks in Scorpius-Centaurus with the Gemini Planet Imager

Justin Hom, Jennifer Patience, Thomas M. Esposito +57

We present the first spatially resolved scattered-light images of four debris disks around members of the Scorpius-Centaurus (Sco-Cen) OB Association with high-contrast imaging and…