The X-Ray Sources of M31

Abstract

The well determined distance to M31 provides a unique opportunity to study galactic x-ray sources in a spiral system at a well known distance, without the uncertainty on the luminosity inherent to the study of x-ray sources in our own Galaxy. M31 was extensively mapped with both imaging instruments on board the Einstein satellite. Preliminary results were presented earlier (cf. Long and Van Speybroeck 1983, and references therein), and a list of possible identifications of sources outside the very confused region around the nucleus was given by Crampton et al. (1984). I am reporting the main results obtained so far from the ongoing careful analysis of the x-ray observations.