{
  "bibcode": "2012GCN.13545....1W",
  "body": "J. Wren, P. Wozniak, H. Davis, and W.T. Vestrand\nof Los Alamos National Laboratory report:\n\nThe RAPTOR network of robotic optical telescopes responded to Swift trigger\n529095 (Ukwatta et al., GCN 13530).  Observations began at 10:56:42.0 UT,\n27.9 s after the initial Swift trigger and before the end of the gamma-ray\nemitting interval.  Our observations were performed under clear skies with\nmorning twilight just beginning.  We clearly detect the optical counterpart\n(Ukwatta et al., GCN 13530, and Virgili et al., GCN 13531).  We initially\ndetect the counterpart at a magnitude of 13.2, and at about T+50 s\nit begins to fade steadily at a power law index of about 0.9 for the next\n1000 seconds.  Our unfiltered magnitudes are calibrated against the USNO-B1\nR-band.  The following table gives a sample of some of our observations.\nThe image mid-points are given relative to the initial BAT trigger time.\n\nt-mid(s)  exp(s)  mag     error\n--------------------------------------\n30.4      5       13.21   0.01\n39.8      5       13.28   0.01\n49.2      5       13.35   0.01\n118.4     10      14.18   0.01\n248.8     10      14.97   0.02\n391.8     30      15.36   0.02\n817.0     30      16.11   0.06\n1071.4    30      16.46   0.11",
  "circularId": 13545,
  "createdOn": 1343682947000,
  "email": "jwren@nis.lanl.gov",
  "subject": "GRB 120729A: Early RAPTOR Observations",
  "submitter": "James Wren at LANL  <jwren@nis.lanl.gov>",
  "eventId": "GRB 120729A"
}