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arXiv · 0806.3968

The Chandra Deep Field-South Survey: 2 Ms Source Catalogs

Abstract

We present point-source catalogs for the ~2 Ms exposure of the Chandra Deep Field-South (CDF-S); this is one of the two most-sensitive X-ray surveys ever performed. The survey covers an area of ~436 arcmin^2 and reaches on-axis sensitivity limits of ~1.9x10^{-17} and ~1.3x10^{-16} ergs/cm^2/s for the 0.5-2.0 and 2-8 keV bands, respectively. Four hundred and sixty-two X-ray point sources are detected in at least one of three X-ray bands that were searched; 135 of these sources are new compared to the previous ~1 Ms CDF-S detections. Source positions are determined using centroid and matched-filter techniques; the median positional uncertainty is ~0.36". The X-ray-to-optical flux ratios of the newly detected sources indicate a variety of source types; ~55% of them appear to be active galactic nuclei while ~45% appear to be starburst and normal galaxies. In addition to the main Chandra catalog, we provide a supplementary catalog of 86 X-ray sources in the ~2 Ms CDF-S footprint that was created by merging the ~250 ks Extended Chandra Deep Field-South with the CDF-S; this approach provides additional sensitivity in the outer portions of the CDF-S. A second supplementary catalog that contains 30 X-ray sources was constructed by matching lower significance X-ray sources to bright optical counterparts (R<23.8); the majority of these sources appear to be starburst and normal galaxies. The total number of sources in the main and supplementary catalogs is 578. R-band optical counterparts and basic optical and infrared photometry are provided for the X-ray sources in the main and supplementary catalogs. We also include existing spectroscopic redshifts for 224 of the X-ray sources. (Abstract abridged)

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B. Luo, F. E. Bauer, W. N. Brandt, D. M. Alexander, B. D. Lehmer, D. P. Schneider, M. Brusa, A. Comastri, A. C. Fabian, A. Finoguenov, R. Gilli, G. Hasinger, A. E. Hornschemeier, A. Koekemoer, V. Mainieri, M. Paolillo, P. Rosati, O. Shemmer, J. D. Silverman, I. Smail, A. T. Steffen, C. Vignali. 2008-06-24. The Chandra Deep Field-South Survey: 2 Ms Source Catalogs. https://doi.org/10.1086/591248

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