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

Luo, B. and Bauer, F. E. and Brandt, W. N. and Alexander, D. M. and Lehmer, B. D. and Schneider, D. P. and Brusa, M. and Comastri, A. and Fabian, A. C. and Finoguenov, A. and Gilli, R. and Hasinger, G. and Hornschemeier, E. and Koekemoer, A. and Mainieri, V. and Paolillo, M. and Rosati, P. and Shemmer, O. and Silverman, J. D. and Smail, I. and Steffen, A. T. and Vignali, C. (2008) The Chandra Deep Field-South Survey: 2 Ms Source Catalogs. Astrophysical Journal Supplement Series, 179 (1). pp. 19-36. ISSN 0067-0049.

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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 ≈1.9 × 10^(−17) and ≈1.3 × 10^(−16) ergs cm^(−2) s^(−1) 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. Optical R-band 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. The average backgrounds in the 0.5-2.0 and 2-8 keV bands are 0.066 and 0.167 counts Ms^(−1) pixel^(−1), respectively, and the background counts follow Poisson distributions. The effective exposure times and sensitivity limits of the CDF-S are now comparable to those of the ≈2 Ms Chandra Deep Field-North (CDF-N). We also present cumulative number counts for the main catalog and compare the results to those for the CDF-N. The soft-band number counts for these two fields agree well with each other at fluxes higher than ≈2 × 10^(−16) ergs cm^(−2) s^(−1), while the CDF-S number counts are up to ≈25% smaller than those for the CDF-N at fluxes below ≈2 × 10^(−16) ergs cm^(−2) s^(−1) in the soft band and ≈2 × 10^(−15) ergs cm^(−2) s^(−1) in the hard band, suggesting small field-to-field variations.

Item Type:Article
Related URLs:
URLURL TypeDescription
Luo, B.0000-0002-9036-0063
Bauer, F. E.0000-0002-8686-8737
Brandt, W. N.0000-0002-0167-2453
Alexander, D. M.0000-0002-5896-6313
Comastri, A.0000-0003-3451-9970
Smail, I.0000-0003-3037-257X
Additional Information:© 2008. The American Astronomical Society. Received 2008 April 21; accepted 2008 June 20. Support for this work was provided by NASA through Chandra Award SP8-9003A (B. L., F. E. B., W. N. B., M. B., A. F.) issued by the Chandra X-ray Observatory Center, which is operated by the Smithsonian Astrophysical Observatory. We also acknowledge the financial support of the Royal Society (D. M. A. and I.R. S.), the Science and Technology Facilities Council fellowship program (B. D. L.), NSF grant 06-7634 (D. P. S.), contract ASIYINAF I /023/05/0 and grant PRIN-MIUR 2006-02-5203 (A. C., R. G., and C. V.).We thank H. D. Tananbaum for allocating the time for these observations and T. L. Aldcroft, P. Broos, and L. K. Townsley for helpful discussions.
Funding AgencyGrant Number
Science and Technology Facilities Council (STFC)UNSPECIFIED
Agenzia Spaziale Italiana (ASI)ASI/INAF I /023/05/0
Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR)PRIN-MIUR 2006-02-5203
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Subject Keywords:cosmology: observations, diffuse radiation, galaxies: active, surveys, X-rays: galaxies
Record Number:CaltechAUTHORS:20090717-101324172
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:14605
Deposited By: Ruth Sustaita
Deposited On:24 Jul 2009 16:11
Last Modified:31 Oct 2017 22:07

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