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Optical and X-ray Identification of Faint Radio Sources in the GOODS-S ACS Field

J. Afonso·B. Mobasher·A. Koekemoer·R. P. Norris·L. Cram
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Abstract

We present optical and X-ray identifications for the sixty-four radio sources in the GOODS-S ACS field revealed in the ATCA 1.4 GHz survey of the Chandra Deep Field South. Optical identifications are made using the ACS images and catalogs, while the X-ray view is provided by the Chandra X-ray Observatory 1 Ms observations. Redshifts for the identified sources are drawn from publicly available catalogs of spectroscopic observations and multi-band photometric-based estimates. Using this multiwavelength information we provide a first characterization of the faint radio source population in this region. The sample contains a mixture of star-forming galaxies and active galactic nuclei, as identified by their X-ray properties and optical spectroscopy. A large number of morphologically disturbed galaxies is found, possibly related to the star-formation phenomena. In spite of the very deep optical data available in this field, seven of the sixty-four radio sources have no optical identification to z(850)~28 mag. Only one of these is identified in the X-rays.

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J. Afonso, B. Mobasher, A. Koekemoer, R. P. Norris, L. Cram. 2005-10-27. Optical and X-ray Identification of Faint Radio Sources in the GOODS-S ACS Field. https://doi.org/10.1086/498823

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