Astronomy and Astrophysics, volume 388, 100-112 (2002/6-2)
ROSAT X-ray sources in the field of the LMC. II. Statistics of background AGN and X-ray binaries.
Abstract (from CDS):
About 200 X-ray sources from a sample of spectrally hard ROSAT PSPC sources, given in the catalog of Haberl & Pietsch (1999A&AS..139..277H), and observed in a ∼60 square degree field of the LMC during several archival pointed observations with a wide range of exposure times have been reanalyzed. For these sources accurate count rates and hardness ratios have been recalculated. In comparison to Haberl & Pietsch (1999A&AS..139..277H) we used merged data from all available observations and we derived average source parameters by investigating each source individually. From a simulation powerlaw spectral tracks have been derived in the HR1-HR2 plane and ∼170 sources have been classified as background X-ray sources or as LMC X-ray binaries. 80% of the spectrally hard X-ray sources with more than 50 observed counts have been found to be consistent with background X-ray sources and 20% with LMC X-ray binaries (53 sources with AGN and 15 with X-ray binaries). The discovery of a new supersoft source RX J0529.4-6713 at the southern HI boundary of the supergiant shell LMC4 is reported. We find two new candidate X-ray binary systems which are associated with the optical bar of the LMC and additional candidate X-ray binaries which are associated with supergiant shells.