Related papers: Modeling magnesium escape from HD209458b atmospher…
One of the most well-studied exoplanets to date, HD 189733 b, stands out as an archetypal hot Jupiter with many observations and theoretical models aimed at characterizing its atmosphere, interior, host star, and environment. We report here…
Stellar high-energy radiation (X-ray and extreme ultraviolet, XUV) drives atmospheric escape in close-in exoplanets. Given that stellar irradiation depends on the stellar magnetism and that stars have magnetic cycles, we investigate how…
Using a self-consistent atmosphere code, we construct a new model of the atmosphere of the transiting extrasolar giant planet HD 209458b to investigate the disparity between the observed strength of the sodium absorption feature at 589 nm…
Observational evidence for escaping exoplanet atmospheres has been obtained for a few exoplanets to date. It comes from strong transit signals detected in the ultraviolet, most notably in the wings of the hydrogen Lyman-$\alpha$…
The study of exoplanetary atmospheres is key to understand the differences between their physical, chemical and dynamical processes. Up to now, the bulk of atmospheric characterization analysis has been conducted on transiting planets. On…
A multi-fluid model for an atomic hydrogen-proton mixture in the upper atmosphere of extrosolar planet is presented when the continuity and momentum equations of each component have been already solved with an energy equation. The particle…
The magnetosphere of an exoplanet has yet to be unambiguously detected. Investigations of star-planet interaction and neutral atomic hydrogen absorption during transit to detect magnetic fields in hot Jupiters have been inconclusive, and…
Super-puffs are planets with exceptionally low densities ($\rho \lesssim 0.1$~g~cm$^{-3}$) and core masses ($M_c \lesssim 5 M_\oplus$). Many lower-mass ($M_p\lesssim10M_\oplus$) super-puffs are expected to be unstable to catastrophic mass…
We present a time-dependent radiative model of the atmosphere of HD209458b and investigate its thermal structure and chemical composition. In a first step, the stellar heating profile and radiative timescales were calculated under…
Characterising the atmospheres of exoplanets is key to understanding their nature and provides hints about their formation and evolution. High-resolution measurements of the helium triplet, He(2$^{3}$S), absorption of highly irradiated…
Detecting heavy atoms in the inflated atmospheres of giant exoplanets that orbit close to their parent stars is a key factor for understanding their bulk composition, and the processes that drive their expansion and interaction with the…
Water, methane and carbon-monoxide are expected to be among the most abundant molecules besides molecular hydrogen in the hot atmosphere of close-in EGPs. Transit observations in the mid-IR allow the atmospheric content of transiting…
Absorption of stellar X-ray and Extreme Ultraviolet radiation in the upper atmosphere of close-in exoplanets can give rise to hydrodynamic outflows, which may lead to the gradual shedding of their primordial, light element envelopes. Excess…
We analyze the absorption and emission-line profiles produced by a set of simple, cool gas wind models motivated by galactic-scale outflow observations. We implement monte carlo radiative transfer techniques that track the propagation of…
Lyman $\alpha$ observations during an exoplanet transit have proved to be very useful to study the interaction between the stellar wind and the planetary atmosphere. They have been extensively used to constrain planetary system parameters…
We present two-dimensional multi-fluid numerical modelling of the upper atmosphere of the hot Jupiter WASP-12b. The model includes hydrogen chemistry, and self-consistently describes the expansion of the planetary upper atmosphere and mass…
The detection of hot atomic hydrogen and heavy atoms and ions at high altitudes around close-in extrasolar giant planets (EGPs) such as HD209458b imply that these planets have hot and rapidly escaping atmospheres that extend to several…
The growth of spectroscopic observations of exoplanetary systems allows the possibility of testing theoretical models and studying the interaction that exoplanetary atmospheres have with the wind and the energetic photons from the star. In…
Using a global 3D, fully self-consistent, multi-fluid hydrodynamic model, we simulate the escaping upper atmosphere of the warm Neptune GJ436b, driven by the stellar XUV radiation impact and gravitational forces and interacting with the…
Recent James Webb Space Telescope observations of cool, rocky exoplanets reveal a probable lack of thick atmospheres, suggesting prevalent escape of the secondary atmospheres formed after losing primordial hydrogen. Yet, simulations…