Related papers: Star-planet interaction through spectral lines
The interaction between the magnetic fields of late-type stars and their close-by planets may produce stellar flares as observed in active binary systems. However, in spite of several claims, conclusive evidence is still lacking. We…
The theory of remote sensing shows that observing a planet at multiple phase angles ($\alpha$) is a powerful strategy to characterize its atmosphere. Here, we analyse how the information contained in reflected-starlight spectra of…
Exoplanets that orbit close to their host stars are much more highly irradiated than their Solar System counterparts. Understanding the thermal structures and appearances of these planets requires investigating how their atmospheres respond…
Context: Several studies have so far placed useful constraints on planetary atmospheric properties using transmission spectrsocopy, and in the case of HD209458b even the radial velocity of the planet during the transit event has been…
We calculated an atmospheric grid for hot mini-Neptune and giant exoplanets, that links astrophysical observable parameters- orbital distance and stellar type- with the chemical atmospheric species expected. The grid can be applied to…
Exoplanets on eccentric orbits experience an incident stellar flux that can be markedly larger at periastron versus apoastron. This variation in instellation can lead to dramatic changes in atmospheric structure in regions of the atmosphere…
We propose a new data analysis method for obtaining transmission spectra of exoplanet atmospheres and brightness variation across the stellar disk from transit observations. The new method is capable of recovering exoplanet atmosphere…
(Abridged) We search for evidence of star-planet magnetic interactions in the nearby Proxima Centauri planetary system using high-quality, high-spectral-resolution optical observations. We measure a photospheric stellar rotation period of…
Absorption of stellar H\alpha\ by the upper atmosphere of the planet HD189733b has recently been detected by Jensen et al. Motivated by this observation, we have developed a model for atomic hydrogen in the n=2 state and compared the…
Exoplanets are now being discovered in profusion. However, to understand their character requires spectral models and data. These elements of remote sensing can yield temperatures, compositions, and even weather patterns, but only if…
High resolution spectroscopy has allowed for unprecedented levels of atmospheric characterization, especially for the hottest gas giant exoplanets known as ultrahot Jupiters (UHJs). High-resolution spectra are sensitive to 3D effects,…
One of the great quests of astronomy is to obtain the spectrum of a terrestrial planet orbiting within the habitable zone of its star, and the dominant challenge in doing so is to isolate the light of the planet from that of the star.…
The absorption signals of metastable He in HD 209458b and several other exoplanets can be explained via escaping atmosphere model with a subsolar He/H ratio. The low abundance of helium can be a result of planet formation if there is a…
The Wide Field Camera 3 (WFC3) on Hubble Space Telescope (HST) is currently one of the most widely used instruments for observing exoplanetary atmospheres, especially with the use of the spatial scanning technique. An increasing number of…
In gamma-ray binaries neutron star is orbiting a companion that produces a strong stellar wind. We demonstrate that observed properties of "stellar wind"-"pulsar wind" interaction depend both on the overall wind thrust ratio, as well as…
The analysis of exoplanetary atmospheres by means of high-resolution spectroscopy is an expanding research field which provides information on chemical composition, thermal structure, atmospheric dynamics and orbital velocity of exoplanets.…
Based on our previous work (Vidotto et al. 2009a), we investigate the effects on the wind and magnetospheric structures of weak-lined T Tauri stars due to a misalignment between the axis of rotation of the star and its magnetic dipole…
With the discovery of ever smaller and colder exoplanets, terrestrial worlds with hazy atmospheres must be increasingly considered. Our Solar System's Titan is a prototypical hazy planet, whose atmosphere may be representative of a large…
During primary transits, the spectral signatures of an exoplanet atmosphere can be measured using transmission spectroscopy. The goal of this work is to accurately measure the atomspheric sodium absorption light curve in HD189733b,…
Exoplanets orbiting M-dwarfs within habitable zones are exposed to stellar environments more extreme than that terrestrial planets experience in our Solar System, which can significantly impact the atmospheres of the exoplanets and affect…