相关论文: Mass-loss rates for transiting exoplanets
Exoplanets with short orbit period reside very close to their host stars. They transition very rapidly between different sectors of the circumstellar space environment along their orbit, leading to large variations of the magnetic field in…
According to theory, high energy emission from the coronae of cool stars can severely erode the atmosphere of orbiting planets. To test the long term effects of the erosion we study a large sample of planet-hosting stars observed in X-rays.…
Systems of close-in super-Earths display striking diversity in planetary bulk density and composition. Giant impacts are expected to play a role in the formation of many of these worlds. Previous works, focused on the mechanical shock…
We present a uniform analysis of the atmospheric escape rate of Neptune-like planets with estimated radius and mass (restricted to $M_{\rm p}<30\,M_{\oplus}$). For each planet we compute the restricted Jeans escape parameter, $\Lambda$, for…
Aims. In this letter, we calculate for the first time the full transonic hydrodynamic escape of an Earth-like atmosphere. We consider the case of an Earth-mass planet with an atmospheric composition identical to that of the current Earth…
Atmospheric escape has been detected from the exoplanet HD 209458b through transit observations of the hydrogen Lyman-alpha line. Here we present spectrally resolved Lyman-alpha transit observations of the exoplanet HD 189733b at two…
The role of charge exchange in shaping exoplanet photoevaporation remains a topic of contention. Exchange of electrons between stellar wind protons from the exoplanet's host star and neutral hydrogen from the planet's wind has been proposed…
High energy radiation from a planet host star can have strong influence on the final habitability of a system through several mechanisms. In this context we have constructed a catalogue containing the X-ray luminosities, as well as basic…
Volatile loss from exoplanetary atmospheres and its possible implications for the longevity of habitable surface conditions is a topic of vigorous debate currently. The vast majority of the habitable zone terrestrial-like exoplanets known…
Atmospheric escape shapes the fate of exoplanets, with statistical evidence for transformative mass loss imprinted across the mass-radius-insolation distribution. Here we present transit spectroscopy of the highly irradiated, low-gravity,…
Planets in close orbits around their host stars are subject to strong irradiation. High-energy irradiation, originating from the stellar corona and chromosphere, is mainly responsible for the evaporation of exoplanetary atmospheres. We have…
We calculate the rate of photoevaporation of a circumstellar disk by energetic radiation (FUV, 6eV $<h\nu<$13.6eV; EUV, 13.6eV $<h\nu<$0.1keV; and Xrays, $h\nu>0.1$keV) from its central star. We focus on the effects of FUV and X-ray photons…
Exoplanets on close-in orbit are subject to intense X-ray and ultraviolet (XUV) irradiation from their star. Their atmosphere therefore heats up, sometimes to the point where it thermally escapes from the gravitational potential of the…
Long-period transiting exoplanets provide an opportunity to study the mass-radius relation and internal structure of extrasolar planets. Their studies grant insights into planetary evolution akin to the Solar System planets, which, in…
We investigate the evaporation history of known transiting exoplanets in order to consider the origin of observed correlations between mass, surface gravity and orbital period. We show that the survival of the known planets at their current…
A large number of terrestrial planets in the classical habitable zone of stars of different spectral types has already been discovered and many are expected to be discovered in near future. However, owing to the lack of knowledge on the…
The K2-33 planetary system hosts one transiting ~5 R_E planet orbiting the young M-type host star. The planet's mass is still unknown, with an estimated upper limit of 5.4 M_J. The extreme youth of the system (<20 Myr) gives the…
Context: When the planet transits its host star, it is possible to measure the planetary radius and (with radial velocity data) the planet mass. For the study of planetary atmospheres, it is essential to obtain transit and occultation…
Stellar flares are a frequent occurrence on young low-mass stars around which many detected exoplanets orbit. Flares are energetic, impulsive events, and their impact on exoplanetary atmospheres needs to be taken into account when…
The amount of ultraviolet irradiation and ablation experienced by a planet depends strongly on the temperature of its host star. Of the thousands of extra-solar planets now known, only four giant planets have been found that transit hot,…