{
  "bibcode": "2005GCN..4107....1B",
  "body": "A. J. Blustin (UCL-MSSL), A. Parsons (GSFC), S. T. Holland (GSFC),\nP. Meszaros, M. Chester (PSU), N. Gehrels (GSFC) on behalf of\nthe Swift/UVOT team report:\n\nThe Swift/UVOT began taking a settled exposure of the field of\nGRB 051016B 78 s after the trigger (Parsons et al. GCN 4103).\nA faint optical/UV source (not visible in the DSS) is detected\nin summed images at the position reported by Chen et al. (GCN 4105)\nat greater than 3 sigma in four of the UVOT filters; the\nmagnitudes and upper limits are as follows:\n\nFilter  T_range(sec)  Exp(sec)  Mag/3-sig upper limit\n\nV       78-29720      2418      20.5 (upper limit)\nB       445-28020     2748      22.0 +/- 0.5\nU       391-35505     2507      20.9 +/- 0.3\nUVW1    337-34740     2796      21.7 +/- 0.4\nUVM2    283-33833     2798      21.0 (upper limit)\nUVW2    554-28928     2748      22.8 +/- 0.6\n\nThe detection in UVW2 would imply that the redshift of the source\nis less than ~1.3.\n\nThere was a further uncatalogued nearby UV-only source at\n(J2000 08:48:27.7 +13:39:12.0), outside the XRT error circle,\nwith the following magnitudes:\n\nFilter   Mag\n\nUVW1     21.9 +/- 0.4\nUVM2     22.3 +/- 0.4\nUVW2     22.0 +/- 0.3\n\nFurther data will be required to tell whether either source is\nvariable.\n\n\n\n\n\n\n\n\n\n\n\n_______________________________________________\nUvot_cal mailing list\nUvot_cal@phoenix.astro.psu.edu\nhttps://phoenix.astro.psu.edu/mailman/listinfo/uvot_cal",
  "circularId": 4107,
  "createdOn": 1129556759000,
  "email": "ajb@mssl.ucl.ac.uk",
  "subject": "GRB 051016B: Swift/UVOT detection",
  "submitter": "Alexander Blustin at MSSL-UCL  <ajb@mssl.ucl.ac.uk>",
  "eventId": "GRB 051016B"
}