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Description
This table contains some of the results from the VLA-COSMOS 3-GHz Large Project based on 384 hours of observations with the Karl G. Jansky Very Large Array (VLA) at 3 GHz (10 cm) toward the 2 square degree Cosmic Evolution Survey (COSMOS) field. The final mosaic reaches a median rms of 2.3 µJy (µJy) beam<sup>-1</sup> over the 2 square degrees at an angular resolution of 0.75 arcseconds. To fully account for the spectral shape and resolution variations across the broad (2-GHz) band, the authors imaged all the data with a multiscale, multifrequency synthesis algorithm. In this table, the catalog of 10,830 radio sources down to 5 sigma is presented, out of which 67 are combined from multiple components. Comparing the positions of these 3-GHz sources with those from the Very Long Baseline Array (VLBA)-COSMOS survey, the authors estimate that the astrometry is accurate to 0.01 arcseconds at the bright end (signal-to-noise ratio, S/N<sub>3GHz</sub> > 20). Survival analysis on these data combined with the VLA-COSMOS 1.4-GHz Joint Project catalog yields an expected median radio spectral index alpha = -0.7. The authors compute completeness corrections via Monte Carlo simulations to derive the corrected 3-GHz source counts. Their counts are in agreement with previously derived 3-GHz counts based on single-pointing (0.087 square degrees) VLA data. In summary, the VLA-COSMOS 3-GHz Large Project simultaneously provides the largest and deepest radio continuum survey at high (0.75") angular resolution to date, bridging the gap between last-generation and next-generation surveys. The catalog contains sources selected down to a 5-sigma (where sigma ~2.3 µJy/beam) threshold. This catalog can be used for statistical analyses, accompanied with the corrections given in the data & catalog release paper. All completeness and bias corrections and source counts presented in the paper were calculated using this sample. The total fraction of spurious sources in the COSMOS 2 sq.deg. field is below 2.7% within this catalog. However, an increase of spurious sources up to 24% at 5.0 < S/N < 5.5 is present (for details see Sec. 5.2., Fig. 17 and Table 3 of the reference paper). A subsample with a minimal spurious source fraction can be selected by requiring an additional cutoff S/N >= 5.5 for single component sources (MULTI=0). The total fraction of spurious sources in the COSMOS 2 sq.deg. field within such a selected sample is below 0.4%, and the fraction of spurious sources is below 3% even at the lowest S/N of 5.5. This table was created by the HEASARC in June 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/602/A1">CDS Catalog J/A+A/602/A1</a> file table1.dat, the VLA-COSMOS 3-GHz radio source catalog. This is a service provided by NASA HEASARC .
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