DISCOVERY OF A METER-WAVELENGTH RADIO TRANSIENT IN THE SWIRE DEEP FIELD: 1046+59

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 325 MHz 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 three months, with a typical single-epoch peak flux sensitivity below 0.2 mJy beam{sup -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{sup 2} per 72 observing hours in the direction of 1046+59 and an isotropic transient surface density {Sigma} = 0.12 deg{sup -2}at 95% confidence for sources with average peak flux density higher than 2.1 mJy over 12 hr.

[1]  M. G. Fleming,et al.  THE ALLEN TELESCOPE ARRAY Pi GHz SKY SURVEY. I. SURVEY DESCRIPTION AND STATIC CATALOG RESULTS FOR THE BOÖTES FIELD , 2010, 1009.4443.

[2]  L. Blanchet.  Gravitational Radiation from Post-Newtonian Sources and Inspiralling Compact Binaries , 2002, Living reviews in relativity.

[3]  et al,et al.  Search for gravitational-wave bursts in the first year of the fifth LIGO science run , 2009, 0905.0020.

[4]  R. Gershberg,et al.  Catalogue and bibliography of the UV Cet-type flare stars and related objects in the solar vicinity , 1999 .

[5]  D. Helfand,et al.  Transient pulsed radio emission from a magnetar , 2006, Nature.

[6]  K. Abazajian,et al.  THE SEVENTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY , 2008, 0812.0649.

[7]  M. Mclaughlin,et al.  A Bright Millisecond Radio Burst of Extragalactic Origin , 2007, Science.

[8]  Technology,et al.  The Radiometric Bode’s Law and Extrasolar Planets , 2004, astro-ph/0405343.

[9]  P. Zarka.  Auroral radio emissions at the outer planets: Observations and theories , 1998 .

[10]  D. Gary,et al.  RADIO EMISSION FROM SOLAR FLARES , 1998 .

[11]  T. Lazio,et al.  A powerful bursting radio source towards the Galactic Centre , 2005, Nature.

[12]  E. Momjian,et al.  Discovery of radio emission from the brown dwarf LP944-20 , 2001, Nature.

[13]  P. S. Ray,et al.  SURVEYING THE DYNAMIC RADIO SKY WITH THE LONG WAVELENGTH DEMONSTRATOR ARRAY , 2010, 1010.5893.

[14]  S. Burke-Spolaor,et al.  The millisecond radio sky: transients from a blind single-pulse search , 2009, 0911.1790.

[15]  Alexei V. Filippenko,et al.  Submillijansky Transients in Archival Radio Observations , 2007, 0705.3158.

[16]  B. M. Gaensler,et al.  Long-term Monitoring of Molonglo Calibrators , 1999, Publications of the Astronomical Society of Australia.

[17]  A. Hewish,et al.  Observation of a Rapidly Pulsating Radio Source , 1968, Nature.

[18]  R. Blandford,et al.  Flicker of extragalactic radio sources and refractive interstellar scintillation , 1986 .

[19]  T. Tanaka,et al.  THE CLOSELY POSITIONED THREE RADIO TRANSIENTS IN THE NASU 1.4 GHz WIDE-FIELD SURVEY , 2009 .

[20]  M. H. Wieringa,et al.  A Complete Catalog of Radio Afterglows: The First Five Years , 2003 .

[21]  Marcos J. Montes,et al.  Radio emission from supernovae and gamma-ray bursters , 2002 .

[22]  Frazer N. Owen,et al.  THE DEEP SWIRE FIELD. II. 90 cm CONTINUUM OBSERVATIONS AND 20 cm–90 cm SPECTRA , 2009, 0904.2011.

[23]  B. Rickett.  Refractive interstellar scintillation of radio sources , 1986 .

[24]  Shami Chatterjee,et al.  A 22-yr southern sky survey for transient and variable radio sources using the Molonglo Observatory Synthesis Telescope , 2010, 1011.0003.

[25]  S. Hawley,et al.  STEADY AND TRANSIENT RADIO EMISSION FROM ULTRACOOL DWARFS , 2009, 0905.4197.

[26]  Luc Blanchet,et al.  Gravitational Radiation from Post-Newtonian Sources and Inspiralling Compact Binaries , 2002, Living reviews in relativity.

[27]  H. Rottgering,et al.  The Westerbork Northern Sky Survey (WENSS) I. A 570 square degree Mini-Survey around the North Ecliptic Pole ? , 1997 .

[28]  Rachel L. Webster,et al.  Detection of Crab Giant Pulses Using the Mileura Widefield Array Low Frequency Demonstrator Field Prototype System , 2007, 0705.0404.

[29]  N. Gehrels,et al.  SEARCHES FOR PROMPT RADIO EMISSION AT 151 MHZ FROM THE GAMMA-RAY BURSTS GRB 950430 AND GRB 950706 , 1996 .

[30]  D. Staelin,et al.  Pulsating Radio Sources near the Crab Nebula , 1968, Science.

[31]  Ray W. Klebesadel,et al.  Observations of Gamma-Ray Bursts of Cosmic Origin , 1973 .

[32]  Geoffrey C. Bower,et al.  A Search for Radio Transients in VLA Archival Images of the 3C 286 Field , 2010 .

[33]  J. Hessels,et al.  An automated archival VLA transients survey , 2011, 1103.0511.

[34]  S. Hawley,et al.  From Radio to X-Ray: Flares on the dMe Flare Star EV Lacertae , 2004, astro-ph/0411236.