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The VLA-COSMOS Survey: I. Radio Identifications from the Pilot Project

E. Schinnerer·C. L. Carilli·N. Z. Scoville·M. Bondi·P. Ciliegi·P. Vettolani·O. Le Fevre·A. M. Koekemoer·F. Bertoldi·C. D. Impey
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Abstract

We present a catalog of 246 radio sources found in the central 1 degree of the COSMOS field at 1.4GHz. The VLA pilot project data have a resolution of 1.9"x1.6" and an rms noise limit of ~25-100uJy/beam covering 0.837 sqrdeg. About 20 radio sources are clearly extended and most of them appear to be double-lobed radio galaxies. We find evidence for a cluster of 7 radio sources with an extent of ~10' southeast of the COSMOS field center. This VLA pilot project was undertaken to demonstrate the feasibility of wide-field mosaicking at 2'' resolution at 1.4GHz using the VLA in its A array configuration. The 7-point mosaic data was used to develop the techniques necessary for reduction and analysis. These data will provide the initial astrometric frame for the optical (ground- and space-based) data of the COSMOS 2 sqrdeg survey. In addition, it demonstrates the feasibility of obtaining deep (rms ~ few uJy) radio imaging of this field at 1.4GHz, since the brightest radio emission peak detected within the area covered has a flux density of 13mJy/beam and no strong side-lobes from sources surrounding the COSMOS field were detected. Comparison of the number counts to other deep radio surveys shows that the COSMOS field is a representative deep field in the radio domain.

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E. Schinnerer, C. L. Carilli, N. Z. Scoville, M. Bondi, P. Ciliegi, P. Vettolani, O. Le Fevre, A. M. Koekemoer, F. Bertoldi, C. D. Impey. 2004-08-09. The VLA-COSMOS Survey: I. Radio Identifications from the Pilot Project. https://doi.org/10.1086/424860

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