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Description
This table contains the results of an X-ray campaign towards the young open cluster NGC 6231. The XMM-Newton observations, of a total duration of ~ 180 ks, reveal that NGC 6231 is very rich in the X-ray domain too. Indeed, 610 X-ray sources were detected in the present field of view, centered on the colliding wind binary HD 152248 in the cluster core (RA, Dec J2000.0 of 16 54 10.06, -41 49 30.1). The limiting sensitivity of this survey is approximately 6 x 10^-15<sup>erg/s/cm</sup>2 but clearly depends on the location in the field of view and on the source spectrum. Using different existing catalogs, over 85% of the X-ray sources could be associated with at least one optical and/or infrared counterpart within a limited cross-correlation radius of 2.5 or 3-arcsec according to the optical/IR catalog used. The surface density distribution of the X-ray sources presents a slight N-S elongation. Once corrected for the spatial sensitivity variation of the EPIC instruments, the radial profile of the source surface density is well described by a King profile with a central density of about 8 sources per arcmin<sup>2</sup> and a core radius close to 3.1 arcminutes. The distribution of the X-ray sources seems closely related to the optical source distribution. The expected number of foreground and background sources should represent about 9% of the detected sources, thus strongly suggesting that most of the observed X-ray emitters are physically belonging to NGC 6231. Finally, beside a few bright but soft objects -- corresponding to the early-type stars of the cluster -- most of the sources are relatively faint (~5 x 10<sup>-15</sup> erg/s/cm<sup>2</sup>) with an energy distribution peaked around 1.0 - 2.0 keV. The catalog of the 610 X-ray sources detected in the 30'-diameter field of view of XMM-Newton is presented here, including the equatorial coordinates, logarithmic likelihoods and count rates for the three EPIC instruments and for various energy ranges, as well as the cross-identification of the X-ray sources with various optical/infrared catalogs (2MASS, GSC2.2, USNO B1.0, SSB06) and their most commonly used names (HD/HDE, CD, CPD, Segg., SBL98, Braes), with only the closest identifications being reported here. This table was created by the HEASARC in March 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/454/1047">CDS catalog J/A+A/454/1047</a> files table3.dat and table6.dat. This is a service provided by NASA HEASARC .
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