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Description
This table contains the Chandra source list for the entire area of the Galactic Bulge Survey (GBS) based on the lists provided in Jonker et al. (2011, ApJ, 194, 18: Paper I) and Jonker et al. (2014, ApJS, 210, 18: Paper II). The previous version of this table, based solely on the data presented in Paper I, contained the Chandra source list based on the first three-quarters of the GBS that had been observed as of the date of writing of that paper. Among the goals of the GBS are constraining the neutron star (NS) equation of state and the black hole (BH) mass distribution via the identification of eclipsing NS and BH low-mass X-ray binaries (LMXBs). The latter goal will, in addition, be obtained by significantly enlarging the number of BH systems for which a BH mass can be derived. Further goals include constraining X-ray binary formation scenarios, in particular the common envelope phase and the occurrence of kicks, via source-type number counts and an investigation of the spatial distribution of X-ray binaries, respectively. The GBS targets two strips of 6 degrees by 1 degrees (12 deg<sup>2</sup> in total), one above (1<sup>o</sup> < b < 2<sup>o</sup>) and the other below (-2<sup>o</sup> < b < -1<sup>o</sup>) the Galactic plane in the direction of the Galactic center at X-ray, optical and near-infrared wavelengths. By avoiding the Galactic plane (-1<sup>o</sup> < b < 1<sup>o</sup>) the authors limit the influence of extinction on the X-ray and optical emission but still sample relatively large number densities of sources. The survey is designed such that a large fraction of the X-ray sources can be identified from their optical spectra. The X-ray survey, by design, covers a large area on the sky while the depth is shallow, using 2 ks per Chandra pointing. In this way, the authors maximize the predicted number ratio of (quiescent) LMXBs to cataclysmic variables. The survey is approximately homogeneous in depth to a 0.5-10 keV flux of 7.7 x 10<sup>-14</sup> erg cm<sup>-2</sup> s<sup>-1</sup>. As of Paper I, the authors had covered about three-fourths (8.3 deg<sup>2</sup>) of the projected survey area with Chandra observations providing 1234 unique X-ray sources. In Paper II, the authors find 424 additional X-ray sources in the 63 Chandra observations that they report on there. In the papers, the authors discuss the characteristics and the X-ray variability of the brightest of the sources as well as the radio properties from existing radio surveys. They point out an interesting asymmetry in the number of X-ray sources as a function of their Galactic l and b coordinates which is probably caused by differences in average extinction towards the different parts of the GBS survey area. This table was originally ingested by the HEASARC in June 2011 based on an electronic version of Table 3 from Paper I which was obtained from the ApJS web site. The current version of this table was ingested by the HEASARC in January 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/210">CDS catalog J/ApJS/210</a>,18 file cxogbs.dat, which appears to be the combination of an Table 3 from Paper I with Table 1 from Paper II. This is a service provided by NASA HEASARC .
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