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The Chandra COSMOS Survey. I. Overview and Point Source Catalog

Elvis, Martin and Civano, Francesca and Vignali, Cristian and Puccetti, Simonetta and Fiore, Fabrizio and Cappelluti, Nico and Aldcroft, T. L. and Fruscione, Antonella and Zamorani, G. and Comastri, Andrea and Brusa, Marcella and Gilli, Roberto and Miyaji, Takamitsu and Damiani, Francesco and Koekemoer, Anton M. and Finoguenov, Alexis and Brunner, Hermann and Urry, C. M. and Silverman, John and Mainieri, Vincenzo and Hasinger, Guenther and Griffiths, Richard and Carollo, Marcella and Hao, Heng and Guzzo, Luigi and Blain, Andrew and Calzetti, Daniela and Carilli, C. and Capak, Peter and Ettori, Stefano and Fabbiano, Giuseppina and Impey, Chris and Lilly, Simon and Mobasher, Bahram and Rich, Michael and Salvato, Mara and Sanders, D.B. and Schinnerer, Eva and Scoville, N. and Shopbell, Patrick and Taylor, James E. and Taniguchi, Yoshiaki and Volonteri, Marta (2009) The Chandra COSMOS Survey. I. Overview and Point Source Catalog. Astrophysical Journal Supplement Series, 184 (1). pp. 158-171. ISSN 0067-0049.

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The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8 Ms, Chandra program that has imaged the central 0.5 deg^2 of the COSMOS field (centered at 10 ^h , +02 ^o ) with an effective exposure of ~160 ks, and an outer 0.4 deg^2 area with an effective exposure of ~80 ks. The limiting source detection depths are 1.9 × 10^(–16) erg cm^(–2) s^(–1) in the soft (0.5-2 keV) band, 7.3 × 10^(–16) erg cm^(–2) s^(–1) in the hard (2-10 keV) band, and 5.7 × 10^(–16) erg cm^(–2) s^(–1) in the full (0.5-10 keV) band. Here we describe the strategy, design, and execution of the C-COSMOS survey, and present the catalog of 1761 point sources detected at a probability of being spurious of <2 × 10^(–5) (1655 in the full, 1340 in the soft, and 1017 in the hard bands). By using a grid of 36 heavily (~50%) overlapping pointing positions with the ACIS-I imager, a remarkably uniform (±12%) exposure across the inner 0.5 deg^2 field was obtained, leading to a sharply defined lower flux limit. The widely different point-spread functions obtained in each exposure at each point in the field required a novel source detection method, because of the overlapping tiling strategy, which is described in a companion paper. This method produced reliable sources down to a 7-12 counts, as verified by the resulting logN-logS curve, with subarcsecond positions, enabling optical and infrared identifications of virtually all sources, as reported in a second companion paper. The full catalog is described here in detail and is available online.

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Additional Information:© 2009 The American Astronomical Society. Received 2008 November 4, accepted for publication 2009. July 29. Published 2009 August 27. We thank the Chandra mission planning team, especially Pat Slane and Jan Vrtilek, and the Chandra pipeline data processing team for the extraordinary efforts they put into the successful scheduling and execution of C-COSMOS. We also thank the rest of COSMOS team whose support has been invaluable in reaching this stage. We thank Bin Luo for sensitivity curves of Chandra Deep Fields. We gratefully thank the Chandra EPO team, in particular Eli Bressert, for creating the true color X-ray image. This research has made use of data obtained from the Chandra Data Archive and software provided by the Chandra X-ray Center (CXC) in the application packages CIAO and Sherpa. This work was supported in part by NASA Chandra grant number GO7-8136A (M.E., C.V., M.B., A.F.), NASA contract NAS8-39073 (Chandra X-ray Center), and by NASA/ADP grant NNX07AT02G (TM at UCSD). In Italy this work is supported by ASI/INAF contracts I/023/05/0, I/024/05/0 and I/088/06, by PRIN/MUR grant 2006-02-5203. In Germany this project is supported by the Bundesministerium für Bildung und Forschung/Deutsches Zentrum für Luft und Raumfahrt and the Max Planck Society.
Funding AgencyGrant Number
NASA ChandraGO7-8136A
Agenzia Spaziale Italiana (ASI)I/023/05/0
Agenzia Spaziale Italiana (ASI)I/024/05/0
Agenzia Spaziale Italiana (ASI)I/088/06
Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR)2006-02-5203
Bundesministerium für Bildung und Forschung (BMBF)UNSPECIFIED
Max Planck SocietyUNSPECIFIED
Deutsches Zentrum für Luft und Raumfahrt (DLR)UNSPECIFIED
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Subject Keywords:catalogs; cosmology: observations; galaxies: evolution; quasars: general; surveys; X-rays: general
Record Number:CaltechAUTHORS:20091006-105300882
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Official Citation:The Chandra COSMOS Survey. I. Overview and Point Source Catalog Martin Elvis, Francesca Civano, Cristian Vignali, Simonetta Puccetti, Fabrizio Fiore, Nico Cappelluti, T. L. Aldcroft, Antonella Fruscione, G. Zamorani, Andrea Comastri, Marcella Brusa, Roberto Gilli, Takamitsu Miyaji, Francesco Damiani, Anton M. Koekemoer, Alexis Finoguenov, Hermann Brunner, C.M. Urry, John Silverman, Vincenzo Mainieri, Guenther Hasinger, Richard Griffiths, Marcella Carollo, Heng Hao, Luigi Guzzo, Andrew Blain, Daniela Calzetti, C. Carilli, Peter Capak, Stefano Ettori, Giuseppina Fabbiano, Chris Impey, Simon Lilly, Bahram Mobasher, Michael Rich, Mara Salvato, D.B. Sanders, Eva Schinnerer, N. Scoville, Patrick Shopbell, James E. Taylor, Yoshiaki Taniguchi, and Marta Volonteri 2009 ApJS 184 158-171 doi: 10.1088/0067-0049/184/1/158
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:16182
Deposited By: Ruth Sustaita
Deposited On:06 Oct 2009 21:13
Last Modified:02 Dec 2015 22:42

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