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Description
This table contains a catalog of radio afterglow observations of gamma-ray bursts (GRBs) over a 14 year period from 1997 to 2011. This sample of 304 afterglows consists of 2,995 flux density measurements (including upper limits) at frequencies between 0.6 GHz and 660 GHz, with the majority of data taken in the 8.5-GHz frequency band (1,539 measurements). The authors use this dataset to carry out a statistical analysis of the radio-selected sample. The detection rate of radio afterglows stayed unchanged almost at 31% before and after the launch of the Swift satellite. The canonical long-duration GRB radio light curve at 8.5 GHz peaks at three to six days in the source rest frame, with a median peak luminosity of 10<sup>31</sup> erg/s/Hz. The peak radio luminosities for short-hard bursts, X-ray flashes, and the supernova-GRB classes are an order of magnitude or more fainter than this value. There are clear relationships between the detectability of a radio afterglow and the fluence or energy of a GRB, and the X-ray or optical brightness of the afterglow. However, the authors find few significant correlations between these same GRB and afterglow properties and the peak radio flux density. In their paper, they also produce synthetic light curves at centimeter and millimeter bands using a range of blast wave and microphysics parameters derived from multi-wavelength afterglow modeling, and use them to compare with the radio sample. Finding agreement, the authors extrapolate this behavior to predict the centimeter and millimeter behavior of GRBs which will observed by the Expanded Very Large Array and the Atacama Large Millimeter Array. The compiled sample consists of 304 GRBs observed with radio telescopes between 1997 January and 2011 January, along with the 2011 April 28 Fermi burst, GRB 110428A. The sample consists of a total of 2,995 flux density measurements taken in the frequency range from 0.6 to 660 GHz and spanning a time range from 0.026 to 1,339 days. Most of the afterglows (270 in total) in this sample were observed as part of VLA radio afterglow programs, whereas 15 bursts were observed by the Expanded VLA (EVLA), and 19 southern bursts with the Australia Telescope Compact Array (ATCA). This catalog describes the radio, optical and X-ray afterglow detections (see Section 2.2 of the reference paper): out of the 304 bursts, 123 bursts were observed in the pre-Swift epoch from 1997 until 2004. The remaining 181 bursts were observed between 2005 and 2011 April (the post-Swift epoch). Out of the 95 radio-detected afterglows (see Section 2.2 of the reference paper), 63 had radio lightcurves (i.e., three or more detections in a single radio band), whereas 32 bursts had less than three detections. For the GRBs for which the light curves were available, the authors determined the peak flux density and the time of the peak in the VLA frequency bands (i.e., 1.4 GHz, 4.9 GHz, 8.5 GHz, 15 GHz, and 22.5 GHz bands) by fitting the data with forward shock formula of the form (Frail 2005, IAU Coll. 192, p. 451) given in equation (1) of the reference paper. This formula may not accurately represent the full complexity of the radio lightcurve evolution. However, it is good enough to determine the approximate values for the peak flux density F<sub>m</sub> and the time of the peak t<sub>m</sub>. See the discussion in Section 3.5 of the reference paper for more details and some caveats. For the remaining bursts, the flux density values were taken directly from the data, and hence do not have the best-fit errors for the peak flux, peak time and rest-frame peak time parameters F<sub>m</sub>, t<sub>m</sub> and t<sub>m</sub>/(1+z), respectively. This table was created by the HEASARC in November 2013 based on CDS catalog J/ApJ/746/156 files table1.dat and table4.dat. This is a service provided by NASA HEASARC .
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