Description
This table contains the source catalog from the Allen Telescope Array Twenty-centimeter Survey (ATATS), a multi-epoch (12 visits), 690 deg<sup>2</sup> radio image and catalog at 1.4 GHz. The survey is designed to detect rare, very bright transients as well as to verify the capabilities of the ATA to form large mosaics. The combined image using data from all 12 ATATS epochs has an rms noise sigma = 3.94 mJy beam<sup>-1</sup> and a dynamic range of 180, with a circular beam of 150 arcseconds FWHM. It contains 4408 sources to a limiting sensitivity of 5 sigma = 20 mJy beam<sup>-1</sup>. The authors compare the catalog generated from this 12-epoch combined image to the NRAO VLA Sky Survey (NVSS), a legacy survey at the same frequency, and find that they can measure source positions to better than ~ 20 arcseconds. For sources above the ATATS completeness limit, the median flux density is 97% of the median value for matched NVSS sources, indicative of an accurate overall flux calibration. The authors examine the effects of source confusion due to the effects of differing resolution between the ATATS and NVSS on their ability to compare flux densities. They detect no transients at flux densities greater than 40 mJy in comparison with NVSS and place a 2 sigma upper limit of 0.004 deg<sup>-2</sup> on the transient rate for such sources. These results suggest that the >~ 1 Jy transients reported by Matsumara et al. (2009, AJ, 138, 787) may not be true transients, but rather variable sources at their flux density threshold. This table was created by the HEASARC in September 2010 based on the electronic version of Table 2 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
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