activity
20202026
most citedEarly Release Science of the exoplanet WASP-39b with JWST NIRSpec PRISM

327 citations · 2.1k across the 66 of their papers we have counts for

collaborators

67 papers

astro-ph.EP2026

Recovering the Morning and Evening Limbs of WASP-94Ab from Its Limb-Averaged JWST Transmission Spectrum

Tyler R. Fairnington, Michael Radica, Michael Zhang +5

Recent JWST observations have revealed that the morning and evening limbs of the hot Jupiter WASP-94Ab have very different transmission spectra. An analysis of these resolved limb…

astro-ph.EP2026

The asymmetric limbs of HD 209458 b observed with JWST NIRCam F322W2/F444W

Cathal Maguire, Eva-Maria Ahrer, Charlotte Fairman +6

We present a reanalysis of JWST NIRCam F322W2/F444W transit observations of the hot Jupiter HD 209458 b to extract morning and evening transmission spectra. To determine whether as…

astro-ph.EP2026

Atmospheric Reconnaissance of TRAPPIST-1 f with JWST NIRISS SOSS: No Evidence for the Transit Light Source Effect

Olivia Lim, René Doyon, Ryan J. MacDonald +25

In just over three years of operation, JWST has observed all seven planets of the TRAPPIST-1 system. The two innermost planets were found to have little to no atmosphere, barring t…

astro-ph.EP2026

Strict Limits on Helium Absorption from LHS 1140 b from Four JWST NIRISS Transits

Michael Radica

Orbiting in the habitable zone of its host star, the 1.7 , 5.6 planet LHS 1140 b is a target of great interest. Recently Cherubim et al. (2026) published a det…

astro-ph.EP2026★ 1 cited

KRONOS I: The m JWST Transmission Spectrum of the 23 Myr V1298 Tau c

Matthew M. Murphy, Matthew C. Nixon, Adina D. Feinstein +16

While recent JWST observations of mature super-Earths and sub-Neptunes have frequently revealed featureless transmission spectra, their inflated progenitors offer a unique window i…

astro-ph.SR2026

KRONOS II: Solar-like Umbra and Penumbra Properties on the Young Sun V1298~Tau

Matthew M. Murphy, Adina D. Feinstein, Meir E. Schochet +14

Transiting exoplanets provide a unique laboratory for studying stellar surface heterogeneities via starspot or facular occultations. When observed at multiple wavelengths, this con…

astro-ph.EP2026

The Days Drag On on WASP-121 b: Interpreting its NIRISS Spectroscopic Phase Curve with General Circulation Models

Robert C. Frazier, Emily Rauscher, Jared Splinter +18

Ultra-hot Jupiters present extreme atmospheric phenomena not found in the Solar System. These planets' daysides experience strong temperature inversions, molecular species (includi…

astro-ph.EP2026

Super-Solar Metallicity and Tentative Evidence for Photochemistry on WASP-96b from JWST and Ground-Based VLT Transmission Spectroscopy

Michael Radica, Jake Taylor, Yoav Rotman +13

With its expanded wavelength coverage and increased precision compared to previous space-based observatories, JWST provides the opportunity to revisit benchmark planets and view th…

astro-ph.EP2026

On the Information Content of Ariel Transmission Spectra: Reassessing the Tier System

Michael Radica, Nicolas B. Cowan, Ryan Cloutier +1

The European Space Agency's Ariel mission will conduct a survey of the atmospheric properties of exoplanets around bright stars. The mission is nominally divided into three Tiers.…

astro-ph.EP2026

New Constraints on the M Dwarf Cosmic Shoreline from a Galaxy Far, Far Away

Michael Radica

Whether there is a cosmic shoreline that divides terrestrial planets which have atmospheres from those that don't is one of the biggest open questions in exoplanet science. Most at…

astro-ph.EP2025★ 8 cited

Diversity in the haziness and chemistry of temperate sub-Neptunes

Pierre-Alexis Roy, Björn Benneke, Marylou Fournier-Tondreau +17

Recent transit observations of K2-18b and TOI-270d revealed strong molecular absorption signatures, lending credence to the idea that temperate sub-Neptunes (T=250-40…

astro-ph.EP2025★ 2 cited

Separating flare and secondary atmospheric signals with RADYN modeling of near-infrared JWST transmission spectroscopy observations of TRAPPIST-1

Ward S. Howard, Adam F. Kowalski, Michael Radica +10

Although TRAPPIST-1's temperate planets have the highest transmission signals of any known system, flares contaminate 50-70% of transits at the 1000 ppm level, far above 100 ppm se…

astro-ph.EP2025★ 4 cited

No TiO detected in the hot Neptune-desert planet LTT-9779 b in reflected light at high spectral resolution

Sophia R. Vaughan, Jayne L. Birkby, Natasha E. Batalha +12

LTT-9779 b is an inhabitant of the hot Neptune desert and one of only a few planets with a measured high albedo. Characterising the atmosphere of this world is the key to understan…

astro-ph.EP2025★ 6 cited

Horizontal and vertical exoplanet thermal structure from a JWST spectroscopic eclipse map

Ryan C. Challener, Megan Weiner Mansfield, Patricio E. Cubillos +33

Highly-irradiated giant exoplanets known as "ultra-hot Jupiters" are anticipated to exhibit large variations of atmospheric temperature and chemistry as a function of longitude, la…

astro-ph.EP2025

A complex structure of escaping helium spanning more than half the orbit of the ultra-hot Jupiter WASP-121\,b

Romain Allart, Louis-Philippe Coulombe, Yann Carteret +19

Atmospheric escape of planets on short orbital periods, driven by the host star's irradiation, influences their evolution, composition, and atmospheric dynamics. Our main avenue to…

astro-ph.EP2025★ 7 cited

Possible Evidence for the Presence of Volatiles on the Warm Super-Earth TOI-270 b

Louis-Philippe Coulombe, Björn Benneke, Joshua Krissansen-Totton +25

The search for atmospheres on rocky exoplanets is a crucial step in understanding the processes driving atmosphere formation, retention, and loss. Past studies have revealed the ex…

astro-ph.EP2025

Precise Constraints on the Energy Budget of WASP-121 b from its JWST NIRISS/SOSS Phase Curve

Jared Splinter, Louis-Philippe Coulombe, Robert C. Frazier +20

Ultra-hot Jupiters exhibit day-to-night temperature contrasts upwards of 1000 K due to competing effects of strong winds, short radiative timescales, magnetic drag, and H2 dissocia…

astro-ph.EP2025★ 7 cited

The JWST Rocky Worlds DDT Program reveals GJ 3929b to likely be a bare rock

Qiao Xue, Michael Zhang, Brandon P. Coy +14

We report first results from the JWST Rocky Worlds Director's Discretionary Time program. Two secondary eclipses of the terrestrial exoplanet GJ 3929b were recently observed using…

astro-ph.EP2025★ 1 cited

Strict limits on potential secondary atmospheres on the temperate rocky exo-Earth TRAPPIST-1 d

Caroline Piaulet-Ghorayeb, Björn Benneke, Martin Turbet +23

The nearby TRAPPIST-1 system, with its seven small rocky planets orbiting a late-type M8 star, offers an unprecedented opportunity to search for secondary atmospheres on temperate…

astro-ph.EP2025★ 10 cited

Enriched volatiles and refractories but deficient titanium on the dayside atmosphere of WASP-121b revealed by JWST/NIRISS

Stefan Pelletier, Louis-Philippe Coulombe, Jared Splinter +21

With dayside temperatures elevated enough for all atmospheric constituents to be present in gas form, ultra-hot Jupiters offer a unique opportunity to probe the composition of gian…

astro-ph.EP2025

Detailed Architecture of the L 98-59 System and Confirmation of a Fifth Planet in the Habitable Zone

Charles Cadieux, Alexandrine L'Heureux, Caroline Piaulet-Ghorayeb +12

The L 98-59 system, identified by TESS in 2019, features three transiting exoplanets in compact orbits of 2.253, 3.691, and 7.451 days around an M3V star, with an outer 12.83-day n…

astro-ph.EP2025

An Earth-like Density for the Temperate Earth-sized Planet GJ 12b

Madison Brady, Jacob Bean, Ritvik Basant +9

While JWST has provided us with the opportunity to probe the atmospheres of potentially-habitable planets, observations of the TRAPPIST-1 system have shown us that active stars sev…

astro-ph.EP2025

JWST NIRISS Transmission Spectroscopy of the Super-Earth GJ 357b, a Favourable Target for Atmospheric Retention

Jake Taylor, Michael Radica, Richard D. Chatterjee +18

We present a JWST NIRISS/SOSS transmission spectrum of the super-Earth GJ 357 b: the first atmospheric observation of this exoplanet. Despite missing the first 40 % of the tr…

astro-ph.EP2025

Continuous helium absorption from the leading and trailing tails of WASP-107b

Vigneshwaran Krishnamurthy, Yann Carteret, Caroline Piaulet-Ghorayeb +19

The detection of helium escaping the atmosphere of exoplanets has revolutionized our understanding of atmospheric escape and exoplanetary evolution. Using high-precision spectrosco…