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arXiv · 1611.03501

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

B. Luo·W. N. Brandt·Y. Q. Xue·B. Lehmer·D. M. Alexander·F. E. Bauer·F. Vito·G. Yang·A. R. Basu-Zych·A. Comastri·R. Gilli·Q. -S. Gu·A. E. Hornschemeier·A. Koekemoer·T. Liu·V. Mainieri·M. Paolillo·P. Ranalli·P. Rosati·D. P. Schneider·O. Shemmer·I. Smail·M. Sun·P. Tozzi·C. Vignali·J. -X. Wang
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Abstract

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 ($K_s\le23$) 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 $\approx1.9\times10^{-17}$, $6.4\times10^{-18}$, and $2.7\times10^{-17}$ 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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B. Luo, W. N. Brandt, Y. Q. Xue, B. Lehmer, D. M. Alexander, F. E. Bauer, F. Vito, G. Yang, A. R. Basu-Zych, A. Comastri, R. Gilli, Q. -S. Gu, A. E. Hornschemeier, A. Koekemoer, T. Liu, V. Mainieri, M. Paolillo, P. Ranalli, P. Rosati, D. P. Schneider, O. Shemmer, I. Smail, M. Sun, P. Tozzi, C. Vignali, J. -X. Wang. 2016-11-10. The Chandra Deep Field-South Survey: 7 Ms Source Catalogs. https://doi.org/10.3847/1538-4365%2F228%2F1%2F2

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