papers

Publications (35)

astro-ph.SR2024

JWST-TST High Contrast: Spectroscopic Characterization of the Benchmark Brown Dwarf HD 19467 B with the NIRSpec Integral Field Spectrograph

Kielan K. W. Hoch, Christopher A. Theissen, Travis S. Barman +14

We present the atmospheric characterization of the substellar companion HD 19467 B as part of the pioneering JWST GTO program to obtain moderate resolution spectra (R2,700, 3…

astro-ph.EP2024

JWST-TST High Contrast: Asymmetries, dust populations and hints of a collision in the Pictoris disk with NIRCam and MIRI

Isabel Rebollido, Christopher C. Stark, Jens Kammerer +21

We present the first JWST MIRI and NIRCam observations of the prominent debris disk around Beta Pictoris. Coronagraphic observations in 8 filters spanning from 1.8 to 23~m prov…

astro-ph.SR2025

On the Orbit of the Binary Brown Dwarf Companion GL229 Ba and Bb

William Thompson, Dori Blakely, Jerry W. Xuan +21

The companion GL229B was recently resolved by Xuan et al. (2024) as a tight binary of two brown dwarfs (Ba and Bb) through VLTI-GRAVITY interferometry and VLT-CRIRES+ RV measuremen…

astro-ph.IM2024

MAUVE: An Ultraviolet Astrophysics Probe Mission Concept

Mayura Balakrishnan, Rory Bowens, Fernando Cruz Aguirre +18

We present the mission concept "Mission to Analyze the UltraViolet universE" (MAUVE), a wide-field spectrometer and imager conceived during the inaugural NASA Astrophysics Mission…

astro-ph.EP2025

JWST Coronagraphic Images of 14 Her c: a Cold Giant Planet in a Dynamically Hot, Multi-planet System

Daniella C. Bardalez Gagliuffi, William O. Balmer, Laurent Pueyo +16

Most observed multi-planet systems are coplanar, in a dynamically "cold" configuration of concentric orbits like our own Solar System. With the James Webb Space Telescope (JWST) we…

astro-ph.EP2023

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…

astro-ph.EP2025

JWST-TST High Contrast: Medium-resolution spectroscopy reveals a carbon-rich circumplanetary disk around the young accreting exoplanet Delorme 1 AB b

Mathilde Mâlin, Kimberly Ward-Duong, Sierra L. Grant +21

Young accreting planetary-mass objects are thought to draw material from a circumplanetary disk (CPD) composed of gas and dust. While the gas within the disk is expected to dispers…

astro-ph.EP2026

JWST-TST High Contrast: First Direct Spectroscopy of GJ 504 b reveals Clouds and Possible Metal Enrichment

Aneesh Baburaj, Jean-Baptiste Ruffio, Marshall Perrin +27

Characterizing the coldest directly imaged companions through direct spectroscopy has only recently become possible with the James Webb Space Telescope. We present moderate-resolut…

astro-ph.EP2024

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

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.EP2025

Follow-Up Exploration of the TWA 7 Planet-Disk System with JWST NIRCam

Katie A. Crotts, Aarynn L. Carter, Kellen Lawson +39

The young M-star TWA 7 hosts a bright and near face-on debris disk, which has been imaged from the optical to the submillimeter. The disk displays multiple complex substructures su…

astro-ph.IM2023

The Science Performance of JWST as Characterized in Commissioning

Jane Rigby, Marshall Perrin, Michael McElwain +623

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performanc…

astro-ph.EP2025

JWST-TST High Contrast: Living on the Wedge, or, NIRCam Bar Coronagraphy Reveals CO in the HR 8799 and 51 Eri Exoplanets' Atmospheres

William O. Balmer, Jens Kammerer, Laurent Pueyo +19

High-contrast observations with JWST can reveal key composition and vertical mixing dependent absorption features in the spectra of directly imaged planets across the 3-5 m wav…

astro-ph.EP2021

Revealing asymmetrical dust distribution in the inner regions of HD 141569

Garima Singh, Trisha Bhowmik, Anthony Boccaletti +42

We obtained polarimetric differential imaging of a gas-rich debris disk around HD 141569A with SPHERE in the H-band to compare the scattering properties of the innermost ring at 44…

astro-ph.EP2024

JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b

David Grant, Nikole K. Lewis, Hannah R. Wakeford +39

Clouds are prevalent in many of the exoplanet atmospheres that have been observed to date. For transiting exoplanets, we know if clouds are present because they mute spectral featu…

astro-ph.EP2024

A JWST MIRI MRS View of the Tel Debris Disk and its Brown Dwarf Companion

Yiwei Chai, Christine H. Chen, Kadin Worthen +12

We report JWST MIRI MRS observations of the Pictoris moving group member, Telescopii ( Tel) A and its brown dwarf binary companion, Tel B. Following PSF subtract…

astro-ph.EP2024

JWST-TST High Contrast: Achieving direct spectroscopy of faint substellar companions next to bright stars with the NIRSpec IFU

Jean-Baptiste Ruffio, Marshall D. Perrin, Kielan K. W. Hoch +33

The JWST NIRSpec integral field unit (IFU) presents a unique opportunity to observe directly imaged exoplanets from 3-5 um at moderate spectral resolution (R~2,700) and thereby bet…

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.EP2025

New Orbital Constraints for YSES 1 b and HR 2562 B from High-Precision Astrometry and Planetary Radial Velocities

Jonathan Roberts, William Thompson, Jason J. Wang +20

We present new VLTI/GRAVITY astrometry and updated orbit fits for the directly imaged companions YSES 1 b and HR 2562 B, substellar objects straddling the planet-brown dwarf bounda…

astro-ph.IM2024

Standing on the Shoulders of Giants: A Comprehensive Spectroscopic Survey of Transiting & High-Contrast Giant Planets

Munazza K. Alam, Emily Rickman, Kielan Hoch +6

We propose a comprehensive survey of giant planets ranging from close-in highly irradiated hot Jupiters to young, wide-orbit directly imaged planets. The combination of two establi…

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.IM2023

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems: Best Practices for Data Collection in Cycle 2 and Beyond

Sasha Hinkley, Beth Biller, Andrew Skemer +35

We present a set of recommended best practices for JWST data collection for members of the community focussed on the direct imaging and spectroscopy of exoplanetary systems. These…

astro-ph.EP2025

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

YSES 2b is a background star: Differential astrometric M-dwarf measurements in time

Matthew Kenworthy, Tomas Stolker, Jens Kammerer +13

We wish to confirm the nature of YSES 2b, a purportedly faint companion of the young star YSES 2. We used on-sky observations from SPHERE and GRAVITY to measure the astrometric pos…

astro-ph.EP2024

VLTI/GRAVITY Observations of AF Lep b: Preference for Circular Orbits, Cloudy Atmospheres, and a Moderately Enhanced Metallicity

William O. Balmer, Kyle Franson, Antoine Chomez +26

Direct imaging observations are biased towards wide-separation, massive companions that have degenerate formation histories. Although the majority of exoplanets are expected to for…

astro-ph.EP2026

JWST NIRCam Reveals the Largest Known M-dwarf Debris Disk Around TWA 10 and New Scattered-Light Observations of the TWA 25 Debris Disk

Katie A. Crotts, Aarynn L. Carter, Beth Biller +26

We present JWST NIRCam observations of two M-dwarf systems located in the TW Hydra association, TWA 10 and TWA 25. Both systems harbor detected debris disks in the F200W and F444W…

astro-ph.EP2025

JWST-TST DREAMS: NIRSpec/PRISM Transmission Spectroscopy of the Habitable Zone Planet TRAPPIST-1 e

Néstor Espinoza, Natalie H. Allen, Ana Glidden +32

TRAPPIST-1 e is one of the very few rocky exoplanets that is both amenable to atmospheric characterization and that resides in the habitable zone of its star -- located at a distan…

astro-ph.EP2026

Direct Images of CO2 Absorption in the Atmosphere of a Super-Jupiter: Enhanced Metallicity Suggestive of Formation in a Disk

William O. Balmer, Laurent Pueyo, Ashley Messier +15

It is unclear how directly imaged substellar companions with masses near the deuterium burning limit form, because these objects are rare and their bulk properties are not diagnost…

astro-ph.EP2025

Differentiating Formation Models with New Dynamical Masses for the PDS 70 Protoplanets

David Trevascus, Sarah Blunt, Valentin Christiaens +22

Hot- and cold-start planet formation models predict differing luminosities for the young, bright planets that direct imaging surveys are most sensitive to. However, precise mass es…

astro-ph.EP2024

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.EP2025

Discovery of a Debris Disk Around TWA 20

Skyler Palatnick, Maxwell A. Millar-Blanchaer, Jingwen Zhang +20

We report the discovery of a debris disk surrounding the M3 star, TWA 20, revealed by JWST coronagraphic observations using the Near-infrared Camera (NIRCam). With reference-star d…

astro-ph.EP2024

JWST/NIRCam 4-5 m Imaging of the Giant Planet AF Lep b

Kyle Franson, William O. Balmer, Brendan P. Bowler +23

With a dynamical mass of , the recently discovered giant planet AF Lep b is the lowest-mass imaged planet with a direct mass measurement. Its youth and spectra…

astro-ph.EP2025

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

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 obta…

astro-ph.IM2024

Investing in the Unrivaled Potential of Wide-Separation Sub-Jupiter Exoplanet Detection and Characterisation with JWST -- Strategic Exoplanet Initiatives with HST and JWST White Paper

Aarynn L. Carter, Rachel Bowens-Rubin, Per Calissendorff +15

We advocate for a large scale imaging survey of nearby young moving groups and star-forming regions to directly detect exoplanets over an unexplored range of masses, ages and orbit…