ﻻ يوجد ملخص باللغة العربية
Transit observations of HD209458b in the UV revealed signatures of neutral magnesium escaping the planets upper atmosphere. The absorption detected in the MgI line provides unprecedented information on the physical conditions at the altitude where the atmospheric blow-off takes place. Here we use a 3D model of atmospheric escape to estimate the transit absorption signatures in the MgI line of their host stars. The detectability of these signatures depends on the brightness of the star and the escape rate of neutral magnesium. We identify a sample of potentially evaporating exoplanets that covers a wide range of stellar and planetary properties, and whose extended exospheres might be detected through MgI line observations with current UV facilities, allowing further steps in comparative exoplanetology.
Close-in exoplanets with highly eccentric orbits are subject to large variations in incoming stellar flux between periapse and apoapse. These variations may lead to large swings in atmospheric temperature, which in turn may cause changes in the chemi
We present scaling laws for advection, radiation, magnetic drag and ohmic dissipation in the atmospheres of hot giant exoplanets. In the limit of weak thermal ionization, ohmic dissipation increases with the planetary equilibrium temperature (T_eq >~
Although atmospheric transmission spectroscopy of HD209458b with the Hubble Space Telescope has been very successful, attempts to detect its atmospheric absorption features using ground-based telescopes have so far been fruitless. Here we present a n
We describe the incorporation of polarized radiative transfer into the atmospheric radiative transfer modelling code VSTAR (Versatile Software for Transfer of Atmospheric Radiation). Using a vector discrete-ordinate radiative transfer code we are abl
Current observations of the atmospheres of close-in exoplanets are predominantly obtained with two techniques: low-resolution spectroscopy with space telescopes and high-resolution spectroscopy from the ground. Although the observables delivered by t