I. De Gennaro Aquino
Research: 3D radiative transfer for chromospheres
The chromosphere is a narrow (order of 10E3 km) layer above the stellar photosphere. Easily observed for the Sun during total eclipses, characterized by a reddish-pink colour, it is easily detected on late type stars through several line diagnostics, most noticeably Ha and Ca II emission lines. The characterization and modelling of this narrow layer, which is the interface between the optically thick photosphere and the optically thin highly ionized corona, has been puzzling astrophysicist for decades. A complete description, with a full solution of the radiative transfer, 3D treatment of the plasma and time evolution, is nowadays impossible to obtain, but several MHD codes have been successfully designed to simulate the evolution of the plasma showing good agreement with solar and stellar observations. With PHOENIX, in its state-of-art 3D implementation, it is then possible to calculate the radiative transfer solution for these MHD models.