Description
This table contains the X-ray source catalogs for the ~7 Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 square arcminutes. Utilizing WAVDETECT for initial source detection and ACIS Extract for photometric extraction and significance assessment, the authors have created a main source catalog (entries with source_sample = 'M' in this HEASARC table) containing 1,008 sources that are detected in up to three X-ray bands: 0.5-7.0 keV, 0.5-2.0 keV, and 2-7 keV. A supplementary source catalog entries with source_sample = 'S' in this HEASARC table) is also provided, including 47 lower-significance sources that have bright (K<sub>s</sub> <~ 23<sup>m</sup>) near-infrared (NIR) counterparts. The authors have identified multiwavelength counterparts for 992 (98.4%) of the 1,008 main-catalog sources, and they have collected redshifts for 986 of these sources, including 653 spectroscopic redshifts and 333 photometric redshifts. Based on the X-ray and multiwavelength properties, the authors have identified 711 active galactic nuclei (AGNs) from the main-catalog sources. Compared to the previous ~4 Ms CDF-S catalogs, 291 of the main-catalog sources are new detections. The observations utilized in this survey have achieved unprecedented X-ray sensitivity with average flux limits over the central ~1 arcmin<sup>2</sup> region of ~1.9 x 10<sup>-17</sup>, 6.4 x 10<sup>-18</sup>, and 2.7 x 10<sup>-17</sup> erg cm<sup>-2</sup> s<sup>-1</sup> in the three X-ray bands, respectively. In the reference paper, the authors provide cumulative number-count measurements observing, for the first time, that normal galaxies start to dominate the X-ray source population at the faintest 0.5-2.0 keV flux levels. The highest X-ray source density reaches ~50,500 deg<sup>-2</sup>, and 47% +/- 4% of these sources are AGNs (~23,900 deg<sup>-2</sup>). The authors adopted a binomial no-source probability value, P<sub>B</sub> < 0.007 as the criterion to prune their initial candidate source list and generate a main source catalog, which includes 1,008 sources with a ~97% multiwavelength-identification rate. This adopted P<sub>B</sub> threshold will have inevitably rejected real X-ray sources. To recover some of these real sources, the authors created a supplementary source catalog that contains lower-significance X-ray sources that have bright optical/NIR counterparts; the chance of a bright optical/NIR source being associated with a spurious X-ray detection is quite small. A total of 47 candidate CDF-S sources having 0.007 <= P<sub>B</sub> < 0.1 are associated with bright, K<sub>s</sub> <= 23<sup>m</sup>, TENIS sources, where the false-match rate is only 1.7%, and these 47 sources constitute the supplementary catalog. A Galactic column density of N<sub>H,Gal</sub> = 8.8 * 10<sup>19</sup> cm<sup>-2</sup> along the line of sight to the CDF-S is assumed in this study. All quoted magnitudes are in the AB system. A cosmology with H<sub>0</sub> = 67.8 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.308, and Omega<sub>Lambda</sub> = 0.692 (Planck Collaboration et al. 2016 values) is used to calculate luminosities. This HEASARC table contains the 1,008 sources from the main Chandra source catalog (these entries are identified by the HEASARC-created source_sample parameter being set to 'M' in this table) and the 47 lower-significance sources from the supplementary NIR-bright Chandra source catalog (these entries are identified by the HEASARC-created source_sample parameter being set to 'S' in this table). This table thus has 1,055 entries. This table was created by the HEASARC in March 2017 based upon electronic versions of Tables 4 and 5, the 'Main Chandra Source Catalog' and the 'Supplementary NIR-Bright Chandra Source Catalog', respectively, which were obtained from the ApJS website. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .
|