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The Chandra Deep Field-South Survey: 7 Ms Source Catalogs

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 نشر من قبل Bin Luo
 تاريخ النشر 2016
  مجال البحث فيزياء
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We present X-ray source catalogs for the $approx7$ Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 arcmin$^2$. Utilizing WAVDETECT for initial source detection and ACIS Extract for photometric extraction and significance assessment, we create a main source catalog containing 1008 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 is also provided including 47 lower-significance sources that have bright ($K_sle23$) near-infrared counterparts. We identify multiwavelength counterparts for 992 (98.4%) of the main-catalog sources, and we collect redshifts for 986 of these sources, including 653 spectroscopic redshifts and 333 photometric redshifts. Based on the X-ray and multiwavelength properties, we identify 711 active galactic nuclei (AGNs) from the main-catalog sources. Compared to the previous $approx4$ Ms CDF-S catalogs, 291 of the main-catalog sources are new detections. We have achieved unprecedented X-ray sensitivity with average flux limits over the central $approx1$ arcmin$^2$ region of $approx1.9times10^{-17}$, $6.4times10^{-18}$, and $2.7times10^{-17}$ erg cm$^{-2}$ s$^{-1}$ in the three X-ray bands, respectively. We 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 $approx50,500$ deg$^{-2}$, and $47%pm4%$ of these sources are AGNs ($approx23,900$ deg$^{-2}$).



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