RX J0039.4+4105 , the SIMBAD biblio

This paper reports the results of the analysis of the second ROSAT PSPC survey of M 31 performed in summer 1992. We compare our results with those of the first survey, already published in Supper et al. (1997A&A...317..328S). Within the ∼10.7deg² field of view, 396 individual X-ray sources are detected in the second survey data, of which 164 are new detections. When combined with the first survey, this result in a total of 560 X-ray sources in the field of M 31. Their (0.1keV-2.0keV) fluxes range from 7x10^–15erg/cm²/s to 7.6x10^–12erg/cm²/s, and of these 560 sources, 55 are tentatively identified with foreground stars, 33 with globular clusters, 16 with supernova remnants, and 10 with radio sources and galaxies (including M 32). A comparison with the results of the Einstein M 31 survey reveals 491 newly detected sources, 11 long term variable sources, and 7 possible transient sources. Comparing the two ROSAT surveys, we come up with 34 long term variable sources and 8 transient candidates. For the M 31 sources, the observed luminosities range from 4x10³⁵erg/s to 4x10³⁸erg/s. The total (0.1keV-2.0keV) luminosity of M 31 is (3.4±0.3)x10³⁹erg/s, distributed approximately equally between the bulge and disk. Within the bulge region, the luminosity of a possible diffuse component combined with faint sources below the detection threshold is (2.0±0.5)x10³⁸erg/s. An explanation in terms of hot gaseous emission leads to a maximum total gas mass of (1.0±0.3)x10⁶M_☉.