290 citations · 1.4k across the 23 of their papers we have counts for
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A retrieval challenge exercise for the Ariel mission
Joanna K. Barstow, Quentin Changeat, Katy L. Chubb +5
The Ariel mission, due to launch in 2029, will obtain spectroscopic information for 1000 exoplanets, providing an unprecedented opportunity for comparative exoplanetology. Retrieva…
Why is it So Hot in Here? Exploring Population Trends in Thermal Emission Observations of Hot Jupiters using Planet-Specific Self-Consistent Atmospheric Models
Jayesh M Goyal, Nikole K Lewis, Hannah R Wakeford +2
Thermal emission has now been observed from many dozens of exoplanet atmospheres, opening the gateway to population-level characterization. Here, we provide theoretical explanation…
TRIDENT: A Rapid 3D Radiative Transfer Model for Exoplanet Transmission Spectra
Ryan J. MacDonald, Nikole K. Lewis
Transmission spectroscopy is one of the premier methods used to probe the temperature, composition, and cloud properties of exoplanet atmospheres. Recent studies have demonstrated…
Gemini/GMOS Transmission Spectroscopy of the Grazing Planet Candidate WD 1856+534 b
Siyi Xu, Hannah Diamond-Lowe, Ryan J. MacDonald +12
WD 1856+534 b is a Jupiter-sized, cool giant planet candidate transiting the white dwarf WD 1856+534. Here, we report an optical transmission spectrum of WD 1856+534 b obtained fro…
A comprehensive revisit of select Galileo/NIMS observations of Europa
Ishan Mishra, Nikole Lewis, Jonathan Lunine +4
The Galileo Near Infrared Mapping Spectrometer (NIMS) collected spectra of Europa in the 0.7-5.2 m wavelength region, which have been critical to improving our understanding of…
The Emission Spectrum of the Hot Jupiter WASP-79b from HST/WFC3
Trevor O. Foote, Nikole K. Lewis, Brian M. Kilpatrick +12
Here we present a thermal emission spectrum of WASP-79b, obtained via Hubble Space Telescope Wide Field Camera 3 G141 observations as part of the PanCET program. As we did not obse…
Differentiating Modern and Prebiotic Earth Scenarios for TRAPPIST-1e: High-resolution Transmission Spectra and Predictions for JWST
Zifan Lin, Ryan J. MacDonald, Lisa Kaltenegger +1
The TRAPPIST-1 system is a priority target for terrestrial exoplanet characterization. TRAPPIST-1e, residing in the habitable zone, will be observed during the JWST GTO Program. He…
ACCESS & LRG-BEASTS: a precise new optical transmission spectrum of the ultrahot Jupiter WASP-103b
James Kirk, Ben Rackham, Ryan MacDonald +17
We present a new ground-based optical transmission spectrum of the ultrahot Jupiter WASP-103b (K). Our transmission spectrum is the result of combining five new tran…
HST PanCET Program: A Complete Near-UV to Infrared Transmission Spectrum for the Hot Jupiter WASP-79b
Alexander D. Rathcke, Ryan J. MacDonald, Joanna K. Barstow +12
We present a new optical transmission spectrum of the hot Jupiter WASP-79b. We observed three transits with the STIS instrument mounted on HST, spanning 0.3 - 1.0 um. Combining the…
A Spectral Survey of WASP-19b with ESPRESSO
Elyar Sedaghati, Ryan J. MacDonald, Núria Casasayas-Barris +10
High resolution precision spectroscopy provides a multitude of robust techniques for probing exoplanetary atmospheres. We present multiple VLT/ESPRESSO transit observations of the…
ACCESS: An optical transmission spectrum of the high-gravity, hot Jupiter HAT-P-23b
Ian C. Weaver, Mercedes López-Morales, Munazza K. Alam +11
We present a new ground-based visible transmission spectrum of the high-gravity, hot Jupiter HAT-P-23b, obtained as part of the ACCESS project. We derive the spectrum from five tra…
Bayesian analysis of Juno/JIRAM's NIR observations of Europa
Ishan Mishra, Nikole Lewis, Jonathan Lunine +4
Juno spacecraft's spectrometer JIRAM recently observed the moon Europa in the 2-5 μm wavelength region. Here we present analysis of the average spectrum of a set of observations ne…
Evidence of a Clear Atmosphere for WASP-62b: the Only Known Transiting Gas Giant in the JWST Continuous Viewing Zone
Munazza K. Alam, Mercedes Lopez-Morales, Ryan J. MacDonald +12
Exoplanets with cloud-free, haze-free atmospheres at the pressures probed by transmission spectroscopy represent a valuable opportunity for detailed atmospheric characterization an…
The White Dwarf Opportunity: Robust Detections of Molecules in Earth-like Exoplanet Atmospheres with the James Webb Space Telescope
Lisa Kaltenegger, Ryan J. MacDonald, Thea Kozakis +4
The near-term search for life beyond the solar system currently focuses on transiting planets orbiting small M dwarfs, and the challenges of detecting signs of life in their atmosp…
Why is it so Cold in Here?: Explaining the Cold Temperatures Retrieved from Transmission Spectra of Exoplanet Atmospheres
Ryan J. MacDonald, Jayesh M. Goyal, Nikole K. Lewis
Transmission spectroscopy is a powerful technique widely used to probe exoplanet terminators. Atmospheric retrievals of transmission spectra are enabling comparative studies of exo…
Understanding the atmospheric properties and chemical composition of the ultra-hot Jupiter HAT-P-7b II. Mapping the effects of gas kinetics
Karan Molaverdikhani, Christiane Helling, Ben W. P. Lew +5
The atmospheres of ultra-hot Jupiters are commonly considered to be at thermochemical equilibrium. We aim to provide disequilibrium chemistry maps for a global understanding of the…
The Metal-Rich Atmosphere of the Neptune HAT-P-26b
Ryan J. MacDonald, Nikku Madhusudhan
Transmission spectroscopy is enabling precise measurements of atmospheric H2O abundances for numerous giant exoplanets. For hot Jupiters, relating H2O abundances to metallicities p…
HO abundances and cloud properties in ten hot giant exoplanets
Arazi Pinhas, Nikku Madhusudhan, Siddharth Gandhi +1
Transmission spectroscopy of exoplanets has the potential to provide precise measurements of atmospheric chemical abundances, in particular of hot Jupiters whose large sizes and hi…
Exploring HO Prominence in Reflection Spectra of Cool Giant Planets
Ryan J. MacDonald, Mark S. Marley, Jonathan J. Fortney +1
The H2O abundance of a planetary atmosphere is a powerful indicator of formation conditions. Inferring H2O in the solar system giant planets is challenging, due to condensation dep…
Signatures of Nitrogen Chemistry in Hot Jupiter Atmospheres
Ryan J. MacDonald, Nikku Madhusudhan
Inferences of molecular compositions of exoplanetary atmospheres have generally focused on C, H, and O-bearing molecules. Recently, additional absorption in HST WFC3 transmission s…
Detection of titanium oxide in the atmosphere of a hot Jupiter
Elyar Sedaghati, Henri M. J. Boffin, Ryan J. MacDonald +6
As an exoplanet transits its host star, some of the light from the star is absorbed by the atoms and molecules in the planet's atmosphere, causing the planet to seem bigger; plotti…
Community targets for JWST's early release science program: evaluation of WASP-63b
Brian M. Kilpatrick, Patricio E. Cubillos, Kevin B. Stevenson +21
We present observations of WASP-63b by the Hubble Space Telescope (HST) as part of "A Preparatory Program to Identify the Single Best Transiting Exoplanet for JWST Early Release Sc…
HD 209458b in New Light: Evidence of Nitrogen Chemistry, Patchy Clouds and Sub-Solar Water
Ryan J. MacDonald, Nikku Madhusudhan
Interpretations of exoplanetary transmission spectra have been undermined by apparent obscuration due to clouds/hazes. Debate rages on whether weak HO features seen in exoplane…