activity
20192026
most citedThe JWST Early Release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 Micron Spectrum of the Planetary-Mass Companion VHS 1256-1257 b

176 citations · 478 across the 20 of their papers we have counts for

collaborators

22 papers

astro-ph.EP2026

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems VIII: patchy forsterite and enstatite clouds in the atmosphere of VHS 1256 b, retrieval lessons learned and outlook to the future

Niall Whiteford, Jacqueline K. Faherty, Ben Burningham +123

JWST defines a new era for the data-driven approach of retrieval modelling, which has become a cornerstone tool for the statistical inference of exoplanetary and brown dwarf proper…

astro-ph.IM2026

ForMoSA: Forward Modeling tool for Spectral Analysis

ForMoSA Collaboration, Simon Petrus, Paulina Palma-Bifani +9

ForMoSA (FORward MOdeling tool for Spectral Analysis) is an open-source Python package to fit spectroscopic and photometric observations using a Bayesian framework. It can utilize…

astro-ph.EP2026

Photometric Variability and Rotation of Beta Pictoris b from JWST NIRCam Coronagraphic Imaging

Yifan Zhou, Beth A. Biller, Aarynn L. Carter +28

We report the detection of photometric variability in the directly imaged super-Jupiter Pictoris b. Using JWST NIRCam dual-band coronagraphic imaging, we conducted a 16-hour co…

astro-ph.EP2026★ 1 cited

Planetary-Mass Exosatellite Detected Around the Substellar Companion of a Star

Kevin Hoy, Alice Zurlo, Pablo A. Peña R. +10

Despite more than 6000 exoplanets being discovered to date, no satellite orbiting an exoplanet, an exomoon, has ever been confidently detected. While there are some candidates, the…

astro-ph.EP2026

Next-generation Exo-REM atmospheric models: application to VHS 1256 b to emulate patchy clouds

Alice Radcliffe, Benjamin Charnay, Anne-Marie Lagrange +7

Condensate clouds are a defining feature of brown dwarf and exoplanet atmospheres, producing a broad range of colours on the CMD and giving rise to spectral features such as the di…

astro-ph.EP2026

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems. VII. Molecular Mapping Performance with JWST/MIRI MRS: VHS 1256 b as a case study

Mathilde Mâlin, Anthony Boccaletti, Benjamin Charnay +29

VHS 1256 b was the first planetary-mass companion to be observed with the James Webb Space Telescope's Mid-Infrared Instrument (JWST/MIRI) using the Medium-Resolution Spectrometer…

astro-ph.EP2026

Panchromatic View of the Frigid Jovian Exoplanet COCONUTS-2 b

Matthieu Ravet, Mickaël Bonnefoy, Gaël Chauvin +24

We use a high signal-to-noise MIRI-LRS spectrum (5.45 - 11 m, R ) of COCONUTS-2~b revealing prominent molecular features of HO, CH and NH. This dataset…

astro-ph.EP2025★ 3 cited

Large-amplitude Variability Driven by Giant Dust Storms on a Planetary-mass Companion

Xianyu Tan, Xi Zhang, Mark S. Marley +17

Large-amplitude variations are commonly observed in the atmospheres of directly imaged exoplanets and brown dwarfs. VHS 1256B, the most variable known planet-mass object, exhibits…

astro-ph.EP2025★ 4 cited

ExoplaNeT accRetion mOnitoring sPectroscopic surveY (ENTROPY) - II. Time series of Balmer line profiles of Delorme 1(AB)b

Dorian Demars, Mickaël Bonnefoy, Catherine Dougados +14

Accretion processes in the planetary-mass regime remain poorly constrained, yet they strongly influence planet formation, evolution, and the composition of circumplanetary disks (C…

astro-ph.EP2025★ 26 cited

Silicate clouds and a circumplanetary disk in the YSES-1 exoplanet system

Kielan K. W. Hoch, Melanie Rowland, Simon Petrus +26

Young exoplanets provide a critical link between understanding planet formation and atmospheric evolution. Direct imaging spectroscopy allows us to infer the properties of young, w…

astro-ph.EP2025★ 7 cited

X-SHYNE: X-Shooter spectra of young exoplanet analogs II. Presentation and analysis of the full library

Simon Petrus, Gaël Chauvin, Mickaël Bonnefoy +29

The X-SHYNE library is a homogeneous sample of 43 medium-resolution (R=8000) infrared (0.3-2.5um) spectra of young (<500Myr), low-mass (<20Mjup), and cold (Teff=600-2000K) isolated…

astro-ph.EP2024

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems V: Do Self-Consistent Atmospheric Models Represent JWST Spectra? A Showcase With VHS 1256 b

Simon Petrus, Niall Whiteford, Polychronis Patapis +119

The unprecedented medium-resolution (R~1500-3500) near- and mid-infrared (1-18um) spectrum provided by JWST for the young (140+/-20Myr) low-mass (12-20MJup) L-T transition (L7) com…

astro-ph.EP2023★ 18 cited

A Near-infrared Variability Survey of Young Planetary-mass Objects

Pengyu Liu, Beth A. Biller, Johanna M. Vos +12

We present a photometric variability survey of young planetary-mass objects using the New Technology Telescope in the Js and Ks bands. Surface gravity plays an important role in th…

astro-ph.EP2023

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems III: Aperture Masking Interferometric Observations of the star HIP 65426 at 3.8 um

Shrishmoy Ray, Steph Sallum, Sasha Hinkley +121

We present aperture masking interferometry (AMI) observations of the star HIP 65426 at as a part of the JWST Direct Imaging Early Release Science (ERS) program obtai…

astro-ph.EP2023

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems IV: NIRISS Aperture Masking Interferometry Performance and Lessons Learned

Steph Sallum, Shrishmoy Ray, Jens Kammerer +120

We present a performance analysis for the aperture masking interferometry (AMI) mode on board the James Webb Space Telescope Near Infrared Imager and Slitless Spectrograph (JWST/NI…

astro-ph.EP2022★ 176 cited

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 Micron Spectrum of the Planetary-Mass Companion VHS 1256-1257 b

Brittany E. Miles, Beth A. Biller, Polychronis Patapis +101

We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a 20 M widely separated (8\arcsec, a = 150 au), young, planetary-…

astro-ph.EP2022

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems I: High Contrast Imaging of the Exoplanet HIP 65426 b from 2-16 m

Aarynn L. Carter, Sasha Hinkley, Jens Kammerer +108

We present JWST Early Release Science (ERS) coronagraphic observations of the super-Jupiter exoplanet, HIP 65426 b, with the Near-Infrared Camera (NIRCam) from 2-5 m, and with t…

astro-ph.EP2022★ 51 cited

The JWST Early Release Science Program for the Direct Imaging & Spectroscopy of Exoplanetary Systems

Sasha Hinkley, Aarynn L. Carter, Shrishmoy Ray +83

The direct characterization of exoplanetary systems with high contrast imaging is among the highest priorities for the broader exoplanet community. As large space missions will be…

astro-ph.EP2021★ 52 cited

A wide-orbit giant planet in the high-mass b Centauri binary system

Markus Janson, Raffaele Gratton, Laetitia Rodet +24

Planet formation occurs around a wide range of stellar masses and stellar system architectures. An improved understanding of the formation process can be achieved by studying it ac…

astro-ph.EP2020★ 64 cited

A medium-resolution spectrum of the exoplanet HIP 65426 b

Simon Petrus, Mickaël Bonnefoy, Gaël Chauvin +18

Medium-resolution integral-field spectrographs (IFS) coupled with adaptive-optics such as Keck/OSIRIS, VLT/MUSE, or SINFONI are appearing as a new avenue for enhancing the detectio…

astro-ph.EP2020★ 47 cited

Strong H emission and signs of accretion in a circumbinary planetary mass companion from MUSE

Simon C. Eriksson, Rubén Asensio Torres, Markus Janson +4

Context. Intrinsic H emission can be advantageously used to detect substellar companions because it improves contrasts in direct imaging. Characterising this emission from accre…

astro-ph.EP2019★ 29 cited

A new take on the low-mass brown dwarf companions on wide-orbits in Upper-Scorpius

Simon Petrus, Mickaël Bonnefoy, Gaël Chauvin +10

The Upper-Scorpius association (5-11 Myr) contains a unique population of low-mass (M<30 MJup) brown-dwarfs. The detailed relative characterization of their physical properties (ma…