Submillijansky Transients in Archival Radio Observations

We report the results of a 944 epoch survey for transient sources with archival data from the Very Large Array spanning 22 years with a typical epoch separation of 7 days. Observations were obtained at 5 or 8.4 GHz for a single field of view and achieved a typical point-source detection threshold at the beam center of 300 μJy per epoch. Ten transient sources were detected with a significance threshold such that only one false positive would be expected. Of these transients, eight were detected in only a single epoch. Two transients were too faint to be detected in individual epochs but were detected in 2 month averages. None of the 10 transients was detected in longer term averages or associated with persistent emission in the deep image produced from the combination of all epochs. The cumulative rate for the short-timescale radio transients above 370 μJy at 5 and 8.4 GHz is 0.07 deg-2 yr-1 ≲ R ≲ 40 deg-2 yr-1, where the uncertainty is due to the unknown duration of the transients, 20 minutes < tchar < 7 days. A two-epoch survey for transients will detect 1.5 ± 0.4 transients per square degree above a flux density of 370 μJy. Two transients are associated with galaxies at z = 0.040 and z = 0.249. These may be similar to the peculiar Type Ib/c radio supernova SN 1998bw associated with GRB 980428. We detect no counterparts for six transients in deep optical and infrared imaging. The hosts and progenitors of these transients are unknown.

[1]  T. Tanaka,et al.  High and Low Galactic Latitude Radio Transients in the Nasu 1.4 GHz Wide-Field Survey , 2007 .

[2]  T. Tanaka,et al.  A 3 Jy Radio Burst at a High Galactic Latitude , 2007 .

[3]  M. Kuniyoshi,et al.  A Strong Radio Transient at High Galactic Latitude , 2007 .

[4]  S. Gezari,et al.  Ultraviolet Detection of the Tidal Disruption of a Star by a Supermassive Black Hole , 2006, astro-ph/0612069.

[5]  D. Lorimer,et al.  A Periodically Active Pulsar Giving Insight into Magnetospheric Physics , 2006, Science.

[6]  A. Rau,et al.  The Nature of the Deep Lens Survey Fast Transients , 2006, astro-ph/0604343.

[7]  E. Berger,et al.  Radio Observations of a Large Sample of Late M, L, and T Dwarfs: The Distribution of Magnetic Field Strengths , 2006, astro-ph/0603176.

[8]  D. Frail,et al.  Radio and Optical Follow-up Observations of a Uniform Radio Transient Search: Implications for Gamma-Ray Bursts and Supernovae , 2006 .

[9]  R. N. Manchester,et al.  Transient radio bursts from rotating neutron stars , 2005, Nature.

[10]  Carlos E. C. J. Gabriel,et al.  Astronomical Data Analysis Software and Systems Xv , 2022 .

[11]  Gregory Y. Prigozhin,et al.  Global Characteristics of X-Ray Flashes and X-Ray-Rich Gamma-Ray Bursts Observed by HETE-2 , 2005 .

[12]  W. M. Goss,et al.  A Radio Transient 0.1 Parsecs from Sagittarius A* , 2005, astro-ph/0507221.

[13]  T. Lazio,et al.  A Wide-Field, Low-Frequency Radio Image of the Field of M31. II. Source Classification and Discussion , 2005, astro-ph/0506491.

[14]  T. Sakamoto,et al.  A short γ-ray burst apparently associated with an elliptical galaxy at redshift z = 0.225 , 2005, Nature.

[15]  T. Weekes,et al.  A Multiwavelength View of the TeV Blazar Markarian 421: Correlated Variability, Flaring, and Spectral Evolution , 2005, astro-ph/0505325.

[16]  S. Bilir,et al.  Absolute magnitudes for late-type dwarf stars for Sloan photometry , 2005, astro-ph/0503415.

[17]  S. D. Hyman,et al.  A powerful bursting radio source towards the Galactic Centre , 2005, Nature.

[18]  N. Gehrels,et al.  An expanding radio nebula produced by a giant flare from the magnetar SGR 1806–20 , 2005, Nature.

[19]  Berkeley,et al.  The extreme flare in III Zw 2: evolution of a radio jet in a Seyfert galaxy , 2005, astro-ph/0501616.

[20]  MIT,et al.  An Overabundance of Transient X-Ray Binaries within 1 Parsec of the Galactic Center , 2004, astro-ph/0412492.

[21]  N. Panagia,et al.  Radio emission from supernovae and gamma-ray bursters and the need for the SKA , 2004 .

[22]  S. Hawley,et al.  From Radio to X-Ray: The Quiescent Atmosphere of the dMe Flare Star EV Lacertae , 2006, astro-ph/0604255.

[23]  Arjun Dey,et al.  Submitted to the Astrophysical Journal Letters Mid-Infrared Selection of Active Galaxies , 2004 .

[24]  J. G. Jernigan,et al.  Global characteristics of X-ray flashes and X-ray rich GRBs observed by HETE-2 , 2004, astro-ph/0409128.

[25]  Alejandro Clocchiatti,et al.  The Deep Lens Survey Transient Search. I. Short Timescale and Astrometric Variability , 2004 .

[26]  Larry R. D'Addario,et al.  The Allen Telescope Array , 2004, SPIE Astronomical Telescopes + Instrumentation.

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

[28]  D. Gary,et al.  Statistical Study of Two Years of Solar Flare Radio Spectra Obtained with the Owens Valley Solar Array , 2004 .

[29]  Michael C. Liu,et al.  A Giant Outburst at Millimeter Wavelengths in the Orion Nebula , 2003, astro-ph/0308277.

[30]  S. R. Kulkarni,et al.  A Radio Survey of Type Ib and Ic Supernovae: Searching for Engine-driven Supernovae , 2003, astro-ph/0307228.

[31]  R. Foley,et al.  Optical Photometry and Spectroscopy of the SN 1998bw–like Type Ic Supernova 2002ap , 2003, astro-ph/0307136.

[32]  A. Tzioumis,et al.  First Results from MASIV: The Microarcsecond Scintillation-induced Variability Survey , 2003, astro-ph/0306484.

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

[34]  J. Cordes,et al.  Searches for Fast Radio Transients , 2003, astro-ph/0304364.

[35]  C. B. Moore,et al.  A Survey for Transient Astronomical Radio Emission at 611 MHz , 2003, astro-ph/0304260.

[36]  J. Weatherall,et al.  Nanosecond radio bursts from strong plasma turbulence in the Crab pulsar , 2003, Nature.

[37]  Alison L. Coil,et al.  The DEIMOS spectrograph for the Keck II Telescope: integration and testing , 2003, SPIE Astronomical Telescopes + Instrumentation.

[38]  D. Frail,et al.  Variability of Submillijansky Radio Sources , 2003, astro-ph/0302528.

[39]  A. Moorwood,et al.  Instrument Design and Performance for Optical/Infrared Ground-based Telescopes, , 2003 .

[40]  Daniel Durand,et al.  Astronomical Data Analysis Software and Systems XI , 2009 .

[41]  L. Kedziora-Chudczer,et al.  Interstellar Scintillation of the Polarized Flux Density in Quasar PKS 0405–385 , 2002, astro-ph/0208307.

[42]  M. Guedel.  Stellar Radio Astronomy: Probing Stellar Atmospheres from Protostars to Giants , 2002, astro-ph/0206436.

[43]  D. Branch,et al.  A Search for Radio Emission from Supernovae with Ages from about 1 Week to More than 80 Years , 2002, astro-ph/0204466.

[44]  T. Totani,et al.  Orphan Afterglows of Collimated Gamma-Ray Bursts: Rate Predictions and Prospects for Detection , 2002, astro-ph/0204258.

[45]  E. Ofek,et al.  Orphan Gamma-Ray Burst Radio Afterglows: Candidates and Constraints on Beaming , 2002, astro-ph/0203262.

[46]  C. Carilli,et al.  Radio-to-Far-Infrared Spectral Energy Distribution and Photometric Redshifts for Dusty Starburst Galaxies , 2001, astro-ph/0112074.

[47]  K. Griest,et al.  The Difficulty in Using Orphan Afterglows to Measure Gamma-Ray Burst Beaming , 2001, astro-ph/0103436.

[48]  D. Frail,et al.  Discovery of Radio Emission from the Brown Dwarf LP944-20 , 2001, astro-ph/0102301.

[49]  L. Ho,et al.  Detailed Analysis of Early to Late-Time Spectra of Supernova 1993J , 2000, astro-ph/0006264.

[50]  A. G. de Bruyn,et al.  The Discovery of a Microarcsecond Quasar: J1819+3845. , 1999, The Astrophysical journal.

[51]  M. Skrutskie,et al.  L Dwarfs and the Substellar Mass Function , 1999, astro-ph/9905170.

[52]  M. Feroci,et al.  Discovery of a Radio Flare from GRB 990123 , 1999, astro-ph/9903441.

[53]  S. R. Kulkarni,et al.  An outburst of relativistic particles from the soft γ-ray repeater SGR1900+14 , 1999, Nature.

[54]  G. E. Latimer,et al.  Centimeter-Wavelength Total Flux and Linear Polarization Properties of Radio-loud BL Lacertae Objects , 1998, astro-ph/9810485.

[55]  J. H. Swank,et al.  Rossi X-ray Timing Explorer , 1998, astro-ph/9802188.

[56]  T. Bastian,et al.  A Search for Radio Emission from Extrasolar Planets , 1999 .

[57]  D. Frail,et al.  Radio emission from the unusual supernova 1998bw and its association with the γ-ray burst of 25 April 1998 , 1998, Nature.

[58]  D. Frail,et al.  The radio afterglow from the γ-ray burst of 8 May 1997 , 1997, Nature.

[59]  J. Rhoads.  How to Tell a Jet from a Balloon: A Proposed Test for Beaming in Gamma-Ray Bursts , 1997, astro-ph/9705163.

[60]  B. Paczyński.  Gravitational Microlensing in the Local Group , 1996, astro-ph/9604011.

[61]  Harland W. Epps,et al.  THE KECK LOW-RESOLUTION IMAGING SPECTROMETER , 1995 .

[62]  J. Linsky,et al.  The ROSAT All-Sky Survey of active binary coronae. I - Quiescent fluxes for the RS Canum Venaticorum systems , 1993 .

[63]  Stephen C. Odewahn,et al.  THE AUTOMATED PLATE SCANNER CATALOG OF THE PALOMAR SKY SURVEY I. SCANNING PARAMETERS AND PROCEDURES , 1993 .

[64]  Arlo U. Landolt,et al.  UBVRI Photometric Standard Stars in the Magnitude Range 11 , 1992 .

[65]  D. Frail,et al.  A Transient Radio Source near the Center of the Milky Way Galaxy , 1992, Science.

[66]  M. F. Aller,et al.  The University of Michigan Radio Astronomy Data Base. I. Structure Function Analysis and the Relation between BL Lacertae Objects and Quasi-stellar Objects , 1992 .

[67]  G. Abell,et al.  A Catalog of Rich Clusters of Galaxies , 1989 .

[68]  S. Amy,et al.  A Search for Transient Events at 843 MHz , 1989, Publications of the Astronomical Society of Australia.

[69]  Martin J. Rees,et al.  Tidal disruption of stars by black holes of 106–108 solar masses in nearby galaxies , 1988, Nature.

[70]  R. Wade,et al.  The Radial Velocity Curve and Peculiar TiO Distribution of the Red Secondary Star in Z Chamaeleontis , 1988 .

[71]  H. J. Rood,et al.  An Analysis of Observed Correlations of Abell Clusters in D = 6 Related to their Morphological Classification (Revised RS) , 1987 .

[72]  K. Horne,et al.  AN OPTIMAL EXTRACTION ALGORITHM FOR CCD SPECTROSCOPY. , 1986 .

[73]  P. I. Nelson,et al.  Statistical methods for astronomical data with upper limits. I - Univariate distributions , 1985 .

[74]  D. Walsh,et al.  Transient radio source near the galactic centre , 1976, Nature.

[75]  R. Hjellming,et al.  Radio Spectrum of Cygnus X-1 , 1971, Nature.

[76]  Lee.  The Astronomische Nachrichten , 1858 .