65 citations · 334 across the 16 of their papers we have counts for
13 papers · 1 filter
A High-Resolution NUV Transmission Spectrum of KELT-9b: Mg II and Fe II Escaping from the Hottest Known Giant Planet
Austin Baldwin, Joshua D. Lothringer, Leonardo A. Dos Santos +5
We present high-resolution NUV observations from Hubble Space Telescope's (HST) Space Telescope Imaging Spectrograph (STIS) data for the hottest known gas planet, KELT-9b. Observat…
Tracing the Winds: A Uniform Interpretation of Helium Escape in Exoplanets from Archival Spectroscopic Observations
Patrick McCreery, Leonardo A. Dos Santos, Néstor Espinoza +2
Over the past decade, observations of evaporating exoplanets have become increasingly common, driven by the discovery of the near-infrared helium-triplet line as a powerful probe o…
Stellar X-ray variability and planetary evolution in the DS Tucanae system
George W. King, Lía R. Corrales, Vincent Bourrier +5
We present an analysis of four Chandra observations of the 45 Myr old DS Tuc binary system. We observed X-ray variability of both stars on timescales from hours to months, includin…
Observations of planetary winds and outflows
Leonardo A. Dos Santos
We have recently hit the milestone of 5,000 exoplanets discovered. In stark contrast with the Solar System, most of the exoplanets we know to date orbit extremely close to their ho…
Water and an escaping helium tail detected in the hazy and methane-depleted atmosphere of HAT-P-18b from JWST NIRISS/SOSS
Guangwei Fu, Néstor Espinoza, David K. Sing +11
JWST is here. The early release observation program (ERO) provides us with the first look at the scientific data and the spectral capabilities. One of the targets from ERO is HAT-P…
The Hubble PanCET program: Emission spectrum of hot Jupiter HAT-P-41b
Guangwei Fu, David K. Sing, Drake Deming +6
We present the most complete emission spectrum for inflated hot Jupiter HAT-P-41b combining new HST WFC/G141 spectrum from the Hubble Panchromatic Comparative Exoplanet Treasury (P…
The Maximum Mass-Loss Efficiency for a Photoionization-Driven Isothermal Parker Wind
Shreyas Vissapragada, Heather A. Knutson, Leonardo A. dos Santos +2
Observations of present-day mass-loss rates for close-in transiting exoplanets provide a crucial check on models of planetary evolution. One common approach is to model the planeta…
HST PanCET program: Non-detection of atmospheric escape in the warm Saturn-sized planet WASP-29 b
L. A. dos Santos, V. Bourrier, D. Ehrenreich +10
(Abridged) Short-period gas giant exoplanets are susceptible to intense atmospheric escape due to their large scale heights and strong high-energy irradiation. This process is thou…
The Hubble PanCET program: Long-term chromospheric evolution and flaring activity of the M dwarf host GJ 3470
V. Bourrier, L. A. dos Santos, J. Sanz-Forcada +9
Neptune-size exoplanets seem particularly sensitive to atmospheric evaporation, making it essential to characterize the stellar high-energy radiation that drives this mechanism. Th…
The Hubble PanCET Program: A Metal-rich Atmosphere for the Inflated Hot Jupiter HAT-P-41b
Kyle B. Sheppard, Luis Welbanks, Avi Mandell +14
We present a comprehensive analysis of the 0.3--5\,m transit spectrum for the inflated hot Jupiter HAT-P-41b. The planet was observed in transit with Hubble STIS and WFC3 as par…
Search for helium in the upper atmosphere of the hot Jupiter WASP-127 b using Gemini/Phoenix
Leonardo A. dos Santos, David Ehrenreich, Vincent Bourrier +8
Large-scale exoplanet search surveys have shown evidence that atmospheric escape is a ubiquitous process that shapes the evolution and demographics of planets. However, we lack a d…
The high-energy environment and atmospheric escape of the mini-Neptune K2-18 b
Leonardo A. dos Santos, David Ehrenreich, Vincent Bourrier +6
K2-18 b is a transiting mini-Neptune that orbits a nearby (38 pc) cool M3 dwarf and is located inside its region of temperate irradiation. We report on the search for hydrogen esca…
Observability of hydrogen-rich exospheres in Earth-like exoplanets
Leonardo A. dos Santos, Vincent Bourrier, David Ehrenreich +1
(Abridged) The existence of an extended neutral hydrogen exosphere around small planets can be used as an evidence for the presence of water in their lower atmosphere but, to date,…