368 citations · 1.5k across the 36 of their papers we have counts for
37 papers
The future of high-resolution UV spectroscopy: Science with a UV Échelle spectrograph on the Habitable Worlds Observatory, or a dedicated mission
Annalisa De Cia, David Cont, Kevin Heng +39
High-resolution UV spectroscopy serves a diversity of science cases, from small bodies to planets, stars, and galaxies, but is currently limited to the Hubble Space Telescope and b…
Early Exploration of the Scientific Discovery Space for the Habitable Worlds Observatory
Courtney D. Dressing, Danica Adams, Evelyne Alecian +324
The Habitable Worlds Observatory (HWO) is a future NASA flagship mission concept identified by the Astro2020 Decadal Survey as the highest priority for large space missions. HWO sh…
CHEOPS observations of V1298 Tau: updated planetary densities and implications on the early evolution of the young system
Hinna Shivkumar, Sérgio Gomes, Jean-Michel Désert +9
The young (10-30 Myr) multi-planet system V1298 Tau presents a unique opportunity to probe the early formation and evolution of young systems. We present new CHEOPS observations of…
A metal-poor atmosphere with a hot interior for a young sub-Neptune progenitor: JWST/NIRSpec transmission spectrum of V1298 Tau b
Saugata Barat, Jean-Michel Désert, Sagnick Mukherjee +19
We present the JWST/NIRSpec G395H transmission spectrum of the young (10 - 20 Myr old) transiting planet V1298 Tau b (9.85+/-0.35 Re, Teq=670K). Combined HST and JWST observations…
First Comparative Exoplanetology Within a Transiting Multi-planet System: Comparing the atmospheres of V1298 Tau b and c
Saugata Barat, Jean-Michel Désert, Jayesh M. Goyal +13
The V1298 Tau system (20-30Myr), is a benchmark young multi-planet system that provides the opportunity to perform comparative exoplanetology between planets orbiting the same star…
The open-source sunbather code: modeling escaping planetary atmospheres and their transit spectra
Dion Linssen, Jim Shih, Morgan MacLeod +1
Atmospheric escape is thought to significantly influence the evolution of exoplanets, especially for sub-Jupiter planets on short orbital periods. Theoretical models predict that h…
Atmospheric Mass Loss from TOI-1259 A b, a Gas Giant Planet With a White Dwarf Companion
Morgan Saidel, Shreyas Vissapragada, Jessica Spake +6
The lack of close-in Neptune-mass exoplanets evident in transit surveys has largely been attributed either to photoevaporative mass loss or high-eccentricity migration. To distingu…
Helium in the Extended Atmosphere of the Warm Super-Puff TOI-1420b
Shreyas Vissapragada, Michael Greklek-McKeon, Dion Linssen +11
Super-puffs are planets with exceptionally low densities (~g~cm) and core masses (). Many lower-mass () super-…
Effects of planetary day-night temperature gradients on He 1083 nm transit spectra
Fabienne Nail, Antonija Oklopčić, Morgan MacLeod
A notable fraction of helium observations probing the evaporating atmospheres of short-period gas giants at 1083~nm exhibit a blueshift during transit, which might be indicative of…
A Large and Variable Leading Tail of Helium in a Hot Saturn Undergoing Runaway Inflation
Michael Gully-Santiago, Caroline V. Morley, Jessica Luna +14
Atmospheric escape shapes the fate of exoplanets, with statistical evidence for transformative mass loss imprinted across the mass-radius-insolation distribution. Here we present t…
Detection of an Atmospheric Outflow from the Young Hot Saturn TOI-1268b
Jorge Pérez González, Michael Greklek-McKeon, Shreyas Vissapragada +4
Photoevaporative mass-loss rates are expected to be highest when planets are young and the host star is more active, but to date there have been relatively few measurements of mass…
Expanding the inventory of spectral lines used to trace atmospheric escape in exoplanets
Dion Linssen, Antonija Oklopčić
Escaping exoplanet atmospheres have been observed as deep transit signatures in a few specific spectral lines. Detections have been made in the hydrogen Ly- line, the metastable…
Giant Tidal Tails of Helium Escaping the Hot Jupiter HAT-P-32 b
Zhoujian Zhang, Caroline V. Morley, Michael Gully-Santiago +14
Capturing planets in the act of losing their atmospheres provides rare opportunities to probe their evolution history. Such analysis has been enabled by observations of the helium…
Non-detection of Helium in the Hot Jupiter WASP-48b
Katherine A. Bennett, Seth Redfield, Antonija Oklopčić +3
Hot Jupiters orbiting extremely close to their host star may experience atmospheric escape due to the large amounts of high-energy radiation they receive. Understanding the conditi…
Keck/NIRSPEC studies of He I in the atmospheres of two inflated hot gas giants orbiting K dwarfs: WASP-52b and WASP-177b
James Kirk, Leonardo A. Dos Santos, Mercedes López-Morales +5
We present the detection of neutral helium at 10833A in the atmosphere of WASP-52b and tentative evidence of helium in the atmosphere of the grazing WASP-177b, using high-resolutio…
The Upper Edge of the Neptune Desert Is Stable Against Photoevaporation
Shreyas Vissapragada, Heather A. Knutson, Michael Greklek-McKeon +9
Transit surveys indicate that there is a deficit of Neptune-sized planets on close-in orbits. If this ``Neptune desert' is entirely cleared out by atmospheric mass loss, then plane…
More Evidence for Variable Helium Absorption from HD 189733b
Michael Zhang, P. Wilson Cauley, Heather A. Knutson +5
We present a new Keck/NIRSPEC observation of metastable helium absorption from the upper atmosphere of HD 189733b, a hot Jupiter orbiting a nearby moderately active star. We measur…
A Mirage or an Oasis? Water Vapor in the Atmosphere of the Warm Neptune TOI-674 b
Jonathan Brande, Ian J. M. Crossfield, Laura Kreidberg +14
We report observations of the recently discovered warm Neptune TOI-674 b (5.25 \rearth{}, 23.6 \mearth{}) with the Hubble Space Telescope's Wide Field Camera 3 instrument. TOI-674…
A Search for Planetary Metastable Helium Absorption in the V1298 Tau System
Shreyas Vissapragada, Guðmundur Stefánsson, Michael Greklek-McKeon +28
Early in their lives, planets endure extreme amounts of ionizing radiation from their host stars. For planets with primordial hydrogen and helium-rich envelopes, this can lead to s…
The post-transit tail of WASP-107b observed at 10830A
J. J. Spake, A. Oklopčić, L. A. Hillenbrand
Understanding the effects of high-energy radiation and stellar winds on planetary atmospheres is vital for explaining the observed properties of close-in exoplanets. Observations o…
Stellar Wind Confinement of Evaporating Exoplanet Atmospheres and its Signatures in 1083 nm Observations
Morgan MacLeod, Antonija Oklopčić
Atmospheric escape from close-in exoplanets is thought to be crucial in shaping observed planetary populations. Recently, significant progress has been made in observing this proce…
Metastable Helium Reveals an Extended Atmosphere for the Gas Giant HAT-P-18b
Kimberly Paragas, Shreyas Vissapragada, Heather A. Knutson +6
The metastable helium line at 1083 nm can be used to probe the extended upper atmospheres of close-in exoplanets and thus provide insight into their atmospheric mass loss, which is…
No escaping helium from 55 Cnc e
Michael Zhang, Heather A. Knutson, Lile Wang +3
We search for escaping helium from the hot super Earth 55 Cnc e by taking high-resolution spectra of the 1083 nm line during two transits using Keck/NIRSPEC. We detect no helium ab…
Non-detection of Helium in the Upper Atmospheres of Three Sub-Neptune Exoplanets
David Kasper, Jacob L. Bean, Antonija Oklopčić +5
We present a search for helium in the upper atmospheres of three sub-Neptune size planets to investigate the origins of these ubiquitous objects. The detection of helium for a low…