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Description
The authors have used the Very Large Array (VLA) in C configuration to carry out a sensitive 20-cm radio survey of regions of the sky that have been surveyed in the far-infrared (FIR) over the wavelength range 5 -200 microns (µm) with ISO (Infrared Space Observatory) as part of the European Large-Area ISO Survey (ELAIS). As usual in surveys based on a relatively small number of overlapping VLA pointings, the flux limit varies over the area surveyed: from a 5-sigma limit of 0.135 mJy over an area of 0.12 deg<sup>2</sup> to 1.15 mJy or better over the whole region covered of 4.22 deg<sup>2</sup>. In their paper, the authors present the complete radio catalog of 867 sources, 428 of which form a complete sample in the flux range 0.2 - 1.0 mJy. These regions of the sky have previously been surveyed to shallower flux limits at 20 cm with the VLA as part of the VLA D-configuration NVSS (full width at half-maximum, FWHM = 45arcseconds) and VLA-B configuration FIRST (FWHM = 5 arcseconds) surveys. This whole survey has a nominal 5-sigma flux limit a factor of 2 below that of the NVSS; 3.4 deg<sup>2</sup> of the survey reaches the nominal flux limit of the FIRST survey and 1.5 deg<sup>2</sup> reaches 0.25 mJy, a factor of 4 below the nominal FIRST survey limit. In addition, this survey is at a resolution intermediate between the two surveys and thus is well suited for a comparison of the reliability and resolution-dependent surface brightness effects that affect interferometric radio surveys. The authors have carried out a detailed comparison of their survey and these two independent surveys in order to assess the reliability and completeness of each. Considering the whole sample, they found that to the 5-sigma nominal limits of 2.3 and 1.0 mJy, respectively, the NVSS and FIRST surveys have a completeness of 96<sup>+2</sup><sub>-3</sub> and 89<sup>+2</sup><sub>-3</sub> % and a reliability of 99<sup>+1</sup><sub>-2</sub> and 94<sup>+2</sup><sub>-2</sub> %. The radio observations were obtained of three ISO ELAIS survey regions in the Northern celestial hemisphere (N1 1610+5430, N2 1636+4115 and N3 1429+3306) (see Table 1 of the reference paper for the details of the fields and the individual pointings). The observations are made with the Very Large Array (VLA) radio telescope at 1.4 GHz (20 cm) in the VLA C configuration (maximum baseline 3.4 km) with an angular resolution (FWHM) of ~15 arcseconds. The aim of these VLA observations was to obtain uniform coverage of the ELAIS regions with an rms noise limit of ~50 microJansky (µJy). This table contains the 921 components of 867 total sources detected at a level of >= 5 sigma (44 of which are multiple component sources as defined in Section 4.3 of the reference paper) over a total area of 4.222 deg<sup>2</sup>. There are also entries describing the properties of the total sources for the 44 multi-component sources (for which the positions have been computed as the flux-weighted average positions of their components), and thus this catalog contains 965 (921 + 44) entries. To filter out the latter, component_id values != 'T' should be selected when searching this table. This table was originally ingested by the HEASARC in August 2012, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/302/222">CDS Catalog J/MNRAS/302/222</a> file table3.dat. It was last updated in September 2013 to remove a duplicate entry for the source ELAISR J142743+331323. This is a service provided by NASA HEASARC .
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