VizieR Online Data Catalog: SWIFT observations of gamma-ray burst afterglows (Page+, 2019)

Our objective is to examine the early periods of GRB optical afterglow light curves to determine what fraction of the sample shows significant afterglow emission when Swift UVOT first arrives on target. Therefore, we require a sample of GRB afterglows that (a) are optically bright enough that we can expect to detect the afterglow in settling observations at a significant fraction of the peak flux, (b) were observed soon after the trigger, and (c) have redshifts so that their observed properties can be transformed to the rest frame.

With these criteria in mind, we have started with the sample of GRBs studied by Oates et al. (2012MNRAS.426L..86O). The sample of Oates et al. (2012MNRAS.426L..86O) was drawn from the second UVOT GRB catalogue (Roming et al. 2017ApJS..228...13R), which contains all of the GRBs observed with Swift UVOT from the launch of Swift until 2010 December 25. For our study we have included only objects which have a peak V magnitude of =<16.0, which corresponds to a sample of 23 GRBs.

All of the GRBs in the sample were observed with Swift UVOT in automated target (AT) mode, and the analysis is restricted to those observations obtained in the initial observing segment, roughly the first 24h from the detection of the burst. For each GRB the UVOT V-band sky images and event data were retrieved from the UK Swift Science Data Centre (http://www.swift.ac.uk).

Table A1 gives the photometry for the stars in each GRB field of view.

(1 data file).