A DeepChandraCatalog of X‐Ray Point Sources toward the Galactic Center

(abridged) We present a catalog of 2357 point sources detected during 590 ksof Chandra observations of the 17-by-17 arcminute field around Sgr A*. Thisfield encompasses a physical area of 40 by 40 pc at a distance of 8 kpc. Thecompleteness limit of the sample at the Galactic center is 10^{31} erg s^{-1}(2.0--8.0 keV), while the detection limit is an order of magnitude lower. The281 sources detected below 1.5 keV are mainly in the foreground of the Galacticcenter, while comparisons to the Chandra deep fields at high Galactic latitudessuggest that only about 100 of the observed sources are background AGN. Thesurface density of absorbed sources (not detected below 1.5 keV) falls off as1/theta away from Sgr A*, in agreement with the distribution of stars ininfrared surveys. Point sources brighter than our completeness limit produce10% of the flux previously attributed to diffuse emission. The log(N)-log(S)distribution of the Galactic center sources is extremely steep (power-law slopealpha = 1.7). If this distribution extends down to a flux of 10^{-17} ergcm^{-1} s^{-1} (10^{29} erg s^{-1} at 8 kpc, 2.0--8.0 keV) with the same slope,then point sources would account for all of the previously reported diffuseemission. Therefore, the 2.0--8.0 keV luminosity distribution must flattenbetween 10^{29} - 10^{31} erg s^{-1}. Finally, the spectra of more than half ofthe Galactic center sources are very hard, and can be described by a power law($E^{-Gamma}) with photon index Gamma < 1. Such hard spectra have been seenpreviously only from magnetically accreting white dwarfs and wind-accretingneutron stars, suggesting that there are large numbers of these systems in ourfield.Comment: Published in ApJ. 22 pages, including 15 figures. Minor changes to match published versio