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

232 citations · 1.4k across the 39 of their papers we have counts for

collaborators

41 papers

astro-ph.EP2026

Enhancing the Interpretability of Radial Velocity Analysis Using Leave-one-out Cross-validation

Matthew C. Nixon, Ritvik Basant, Rafael Luque +2

Radial velocity (RV) observations are reaching increasingly high precision, enabling the targeting of low-amplitude signals. Assessing results obtained at the limits of our capabil…

astro-ph.EP2026

Precise Determination of the Metallicity and C/O of WASP-39~b From a Single JWST Instrument Mode with Phase-Resolved Cross-Correlation Retrievals

Arjun B. Savel, Eliza M. -R. Kempton, Erin M. May +4

Measuring atmospheric metallicities and C/O ratios is a key goal of JWST exoplanet science, given their proposed link to planet formation. Achieving this goal has previously been s…

astro-ph.EP2026

C, N, O, S, and photochemistry in a temperate giant planet orbiting a late M dwarf

Michael Zhang, Qiao Xue, Jeehyun Yang +20

We report the JWST NIRSpec/PRISM transit spectrum of TOI-6894b, an exceptional 420 K sub-Saturn that is one of the rare giant planets transiting a late M dwarf. Remarkably, both th…

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.EP2026

Photochemical Production of CS2 in Temperate-to-Warm Gas Giant Exoplanet Atmospheres

Jeehyun Yang, Vighnesh Nagpal, Michael Zhang +16

Sulfur chemistry has emerged as an important probe of exoplanet atmospheres in the JWST era, although observational constraints have thus far been largely limited to SO2 and H2S in…

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

Impact of Clouds on the Atmosphere-Mantle Interface of Sub-Neptunes

Sagnick Mukherjee, Matthew C. Nixon, Luis Welbanks +4

Sub-Neptunes are among the most common type of close-in planets found in our galaxy, yet their bulk composition remains largely uncertain; H-rich envelopes overlaying rocky cores,…

astro-ph.EP2026★ 1 cited

The Identification of CS2 and Evidence for Carbon-Sulfur Chemical Coupling in a Warm Giant Exoplanet Atmosphere

Anastasia Triantafillides, Thomas G. Beatty, Matthew C. Nixon +14

Transmission spectroscopy with the James Webb Space Telescope (JWST) is revealing growing chemical complexity in giant exoplanet atmospheres. Of particular interest is sulfur, whic…

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★ 14 cited

Magma ocean interactions can explain JWST observations of the sub-Neptune TOI-270 d

Matthew C. Nixon, R. Sander Somers, Arjun B. Savel +9

Sub-Neptunes with substantial atmospheres may possess magma oceans in contact with the overlying gas, with chemical interactions between the atmosphere and magma playing an importa…

astro-ph.EP2025★ 6 cited

Not All Sub-Neptune Exoplanets Have Magma Oceans

Bodie Breza, Matthew C. Nixon, Eliza M. -R. Kempton

The evolution and structure of sub-Neptunes may be strongly influenced by interactions between the outer gaseous envelope of the planet and a surface magma ocean. However, given th…

astro-ph.EP2025

A carbon-rich atmosphere on a windy pulsar planet

Michael Zhang, Maya Beleznay, Timothy D. Brandt +17

A handful of enigmatic Jupiter-mass objects have been discovered orbiting pulsars. One such object, PSR\,J2322-2650b, uniquely resembles a hot Jupiter exoplanet due to its minimum…

astro-ph.EP2025

Do Rocky Planets around M Stars Have Atmospheres? A Statistical Approach to the Cosmic Shoreline

Jegug Ih, Eliza M. -R. Kempton, Hannah Diamond-Lowe +6

Answering the question "do rocky exoplanets around M stars have atmospheres?" is a key science goal of the JWST mission, with 500 hours of Director's Discretionary Time (DDT) award…

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★ 20 cited

Challenges in the detection of gases in exoplanet atmospheres

Luis Welbanks, Matthew C. Nixon, Peter McGill +12

Claims of detections of gases in exoplanet atmospheres often rely on comparisons between models including and excluding specific chemical species. However, the space of molecular c…

astro-ph.EP2025

The radiative effects of photochemical hazes on the atmospheric circulation and phase curves of sub-Neptunes

Maria E. Steinrueck, Vivien Parmentier, Laura Kreidberg +13

Measuring the atmospheric composition of hazy sub-Neptunes like GJ~1214b through transmission spectroscopy is difficult because of the degeneracy between mean molecular weight and…

astro-ph.EP2025★ 9 cited

Enabling Robust Exoplanet Atmospheric Retrievals with Gaussian Processes

Yoav Rotman, Luis Welbanks, Michael R. Line +3

Atmospheric retrievals are essential tools for interpreting exoplanet transmission and eclipse spectra, enabling quantitative constraints on the chemical composition, aerosol prope…

astro-ph.EP2025★ 1 cited

TOI-421 b: A Hot Sub-Neptune with a Haze-Free, Low Mean Molecular Weight Atmosphere

Brian Davenport, Eliza M. -R. Kempton, Matthew C. Nixon +8

Common features of sub-Neptunes atmospheres observed to date include signatures of aerosols at moderate equilibrium temperatures (~500-800 K), and a prevalence of high mean molecul…

astro-ph.EP2024

A Fourth Planet in the Kepler-51 System Revealed by Transit Timing Variations

Kento Masuda, Jessica E. Libby-Roberts, John H. Livingston +49

Kepler-51 is a -old Sun-like star hosting three transiting planets with radii - and orbital periods -$130\,\mathrm{day…

astro-ph.EP2024★ 62 cited

A Benchmark JWST Near-Infrared Spectrum for the Exoplanet WASP-39b

A. L. Carter, E. M. May, N. Espinoza +77

Observing exoplanets through transmission spectroscopy supplies detailed information on their atmospheric composition, physics, and chemistry. Prior to JWST, these observations wer…

astro-ph.EP2024

New insights into the internal structure of GJ 1214 b informed by JWST

Matthew C. Nixon, Anjali A. A. Piette, Eliza M. -R. Kempton +7

Recent JWST observations of the sub-Neptune GJ 1214 b suggest that it hosts a high-metallicity (>100x solar), hazy atmosphere. Emission spectra of the planet show molecular absorpt…

astro-ph.EP2024★ 96 cited

Sulphur dioxide in the mid-infrared transmission spectrum of WASP-39b

Diana Powell, Adina D. Feinstein, Elspeth K. H. Lee +70

The recent inference of sulphur dioxide (SO) in the atmosphere of the hot (1100 K), Saturn-mass exoplanet WASP-39b from near-infrared JWST observations suggests that phot…

astro-ph.EP2024★ 1 cited

Hydrogen sulfide and metal-enriched atmosphere for a Jupiter-mass exoplanet

Guangwei Fu, Luis Welbanks, Drake Deming +15

As the closest transiting hot Jupiter to Earth, HD 189733b has been the benchmark planet for atmospheric characterization. It has also been the anchor point for much of our theoret…

astro-ph.EP2024

Simultaneous retrieval of orbital phase resolved JWST/MIRI emission spectra of the hot Jupiter WASP-43b: evidence of water, ammonia and carbon monoxide

Jingxuan Yang, Mark Hammond, Anjali A. A. Piette +14

Spectroscopic phase curves of hot Jupiters measure their emission spectra at multiple orbital phases, thus enabling detailed characterisation of their atmospheres. Precise constrai…