Eclipse Mapping of Symbiotic Binaries

Abstract

We describe an ultraviolet eclipse mapping of the symbiotic binary EG And. Analysis of FUSE and HST/STIS observations at differing orbital phases probe different layers of the chromosphere and wind of the red giant in absorption. Whilst the primary aim of the study is to examine the thermal and dynamic conditions at the base of these winds, much is learnt about both the hot and cool material within the system. It is found that the behavior of the hot material associated with the dwarf is highly variable but the inner wind of the giant is relatively undisturbed due to the wind density and the low-luminosity of the dwarf.