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Description
This table contains a sample of 883 sources detected in a deep Very Large Array (VLA) survey at 1.4 GHz in the Extended-Chandra Deep Field South (E-CDFS). The reference paper focuses on the identification of their optical and infrared (IR) counterparts. The authors use a likelihood-ratio technique that is particularly useful when dealing with deep optical images to minimize the number of spurious associations. They find a reliable counterpart for 95% of their radio sources. Most of the counterparts (74%) are detected at optical wavelengths, but there is a significant fraction (21%) that are only detectable in the IR. Combining newly acquired optical spectra with data from the literature, the authors are able to assign a redshift to 81% of the identified radio sources (37% spectroscopic). They also investigate the X-ray properties of the radio sources using the Chandra 4 Ms and 250 ks observations. In particular, the authors use a stacking technique to derive the average properties of radio objects undetected in the Chandra images. The results of their analysis are collected in this new catalog containing the position of the optical/IR counterpart, the redshift information, and the X-ray fluxes. It is the deepest multi-wavelength catalog of radio sources, which will be used for future study of this galaxy population. The E-CDFS was observed at 1.4 GHz with the VLA between 2007 June and September (Miller et al. 2008, ApJS, 179, 114). The mosaic image covered an area of about 34 by 34 arcminutes with near-uniform sensitivity. The typical rms is 7.4 µJy for a 2.8 by 1.6 arcseconds beam. The second data release (N. Miller et al. 2012, in preparation) provides a new source catalog with a 5-sigma point-source detection limit, for a total of 883 sources. The median value of the distribution is 58.5 µJy and the median signal-to-noise ratio (S/N) is 7.6. The authors note that ~ 90% of the sample has a flux density below 1 mJy, a regime where radio-quiet AGNs and star-forming galaxies (SFGs) become the dominant populations This table was created by the HEASARC in November 2012 based on the files table3.dat and table5.dat which were obtained from the ApJS web site. This is a service provided by NASA HEASARC .
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