Discovery of a meter-wavelength radio transient in the swire deep field: 1046+59

Abstract

We report the results of a low frequency radio variability and slow transient search using archival observations from the Very Long Array. We selected six 325MHz radio observations from the spring of 2006, each centered on the Spitzer-Space-Telescope Wide-area Infrared Extragalactic Survey (SWIRE) Deep Field: 1046+59. Observations were spaced between one day to threemonths, with a typical single-epoch peak flux sensitivity below 0.2mJybeam -1 near the field pointing center. We describe the observation parameters, data post-processing, and search methodology used to identify variable and transient emission. Our search revealed multiple variable sources and the presence of one, day-scale transient event with no apparent astronomical counterpart. This detection implies a transient rate of 1 1 event per 6.5 deg 2 per 72 observing hours in the direction of 1046+59 and an isotropic transient surface density Σ = 0.12 deg -2at 95% confidence for sources with average peak flux density higher than 2.1mJy over 12hr. © 2012. The American Astronomical Society. All rights reserved.