{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["026:00"], "contactPoint": {"@type": "vcard:Contact", "fn": "HEASARC Help Desk", "hasEmail": "mailto:andrew.ptak@nasa.gov"}, "description": "This table contains the results of a complete spectral survey of the X-ray point sources detected in five XMM-Newton observations along the major axis of M 31 but avoiding the central bulge, aimed at establishing the population characteristics of X-ray sources in this galaxy. One observation of each disc field of M 31 was taken using the EPIC pn and MOS cameras on XMM-Newton in January and June 2002. The authors obtained background-subtracted spectra and lightcurves for each of the 335 X-ray point sources detected across the five observations from 2002. They also correlate their source list with those of earlier X-ray surveys and radio, optical and infra-red catalogs. Sources with more than 50 source counts are individually spectrally fit in order to create the most accurate luminosity functions of M 31 to date. Based on the spectral fitting of these sources with a power law model, the authors observe a broad range of best-fit photon index. From this distribution of best-fit index, they identify 16 strong high mass X-ray binary system candidates in M 31. They show the first cumulative luminosity functions created using the best-fit spectral model to each source with more than 50 source counts in the disc of M 31. The cumulative luminosity functions show a distinct flattening in the X-ray luminosity L<sub>X</sub> interval 37.0 <~ log L<sub>X</sub> erg s<sup>-1</sup> <~ 37.5. Such a feature may also be present in the X-ray populations of several other galaxies, but at a much lower statistical significance. The authors investigate the number of AGN present in their source list and find that, above L<sub>X</sub> ~1.4 x 10<sup>36</sup> erg s<sup>-1</sup>, the observed population is statistically dominated by the point source population of M 31. This table was created by the HEASARC in October 2009 based on the electronic version of Table A1 from the reference paper which was obtained from the CDS (their catalog J/A+A/495/733 file tablea1.dat. This is a service provided by NASA HEASARC .", "distribution": [{"@type": "dcat:Distribution", "downloadURL": "https://heasarc.gsfc.nasa.gov/W3Browse/all/m31xmm2.html", "format": "HTML", "mediaType": "text/html"}, {"@type": "dcat:Distribution", "downloadURL": "https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=m31xmm2&", "format": "BIN", "mediaType": "application/octet-stream"}], "identifier": "ivo://nasa.heasarc/m31xmm2", "keyword": ["__"], "landingPage": "ivo://nasa.heasarc/m31xmm2", "license": "https://www.usa.gov/government-works", "modified": "2026-04-13", "programCode": ["026:000"], "publisher": {"@type": "org:Organization", "name": "High Energy Astrophysics Science Archive Research Center"}, "theme": ["Astrophysics"], "title": "M 31 XMM-Newton Spectral Survey X-Ray Point Source Catalog"}