activity
20202026
most citedDetection and Bulk Properties of the HR 8799 Planets with High Resolution Spectroscopy

79 citations · 775 across the 45 of their papers we have counts for

collaborators

47 papers

astro-ph.EP2026

Tracing the Influence of Distant companions on Exoplanetary Systems (TIDES) I. Highly Eccentric and Misaligned Binary Companions to Hot Jupiters

Marvin Morgan, Jerry W. Xuan, Brendan P. Bowler +9

The origin of hot Jupiters remains an open question. A significant fraction reside in binary or multiple star systems, suggesting that stellar companions may play an important role…

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.EP2026

Possible stratospheric emission in the warm Neptune GJ 436 b from high-resolution spectroscopy

Luke Finnerty, Michael P Fitzgerald, Jerry W Xuan +26

We present high spectral resolution band (2.91--3.85 m) observations of the warm Neptune GJ 436 b from Keck II/KPIC. KPIC's single-mode fiber feed reduces the band sky b…

astro-ph.EP2026

Limits on the Post-eclipse Emission Spectrum of HD 80606 b From High-Resolution Spectroscop

Luke Finnerty, Aurora Kesseli, Kyle Pearson +2

We present Keck/NIRSPEC -band observations of HD 80606 b, one of the most eccentric known exoplanets. HD 80606 b was observed after secondary eclipse, close to periastron, when…

astro-ph.EP2026★ 4 cited

Distinct Rotational Evolution of Giant Planets and Brown Dwarf Companions

Chih-Chun Hsu, Jason J. Wang, Jerry W. Xuan +27

We present a rotational velocity (vsini) survey of 32 stellar/substellar objects and giant planets using Keck/KPIC high-resolution spectroscopy, including 6 giant planets (2-7 M$_\…

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

Velocity shift and SNR limits for high-resolution spectroscopy of hot Jupiters using Keck/KPIC

Kevin S. Hong, Luke Finnerty, Michael P. Fitzgerald

High-resolution cross-correlation spectroscopy (HRCCS) is a technique for detecting the atmospheres of close-in planets using the change in the projected planet velocity over a few…

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★ 4 cited

An Early Look at the Performance of IGRINS-2 at Gemini-North with Application to the ultrahot Jupiter, WASP-33 b

Yeon-Ho Choi, Ueejeong Jeong, Jae-Joon Lee +56

Ground-based high-resolution spectroscopy enables precise molecular detections and velocity-resolved atmospheric dynamics, offering a distinct advantage over low-resolution methods…

astro-ph.IM2025★ 9 cited

Technical description and performance of the phase II version of the Keck Planet Imager and Characterizer

Nemanja Jovanovic, Daniel Echeverri, Jacques-Robert Delorme +46

The Keck Planet Imager and Characterizer (KPIC) is a series of upgrades for the Keck II Adaptive Optics (AO) system and the NIRSPEC spectrograph to enable diffraction limited, high…

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★ 6 cited

Fringing analysis and forward modeling of Keck Planet Imager and Characterizer (KPIC) spectra

Katelyn A. Horstman, Jean-Baptiste Ruffio, Jason J. Wang +27

The Keck Planet Imager and Characterizer (KPIC) combines high contrast imaging with high resolution spectroscopy (R~35,000 in K band) to study directly imaged exoplanets and brown…

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

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.SR2024★ 17 cited

Fresh view of the hot brown dwarf HD 984 B through high-resolution spectroscopy

J. C. Costes, J. W. Xuan, A. Vigan +26

Context. High-resolution spectroscopy has the potential to drive a better understanding of the atmospheric composition, physics, and dynamics of young exoplanets and brown dwarfs,…

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…