{
  "bibcode": "2012GCN.13766....1K",
  "body": "Klotz A. (IRAP-CNRS-OMP), Gendre B. (ASDC/INAF-OAR),\nBoer M. (UNS-CNRS-OCA), Atteia J.L. (IRAP-CNRS-OMP) report:\n\nWe continue to observe the afterglow of GRB 120913B\n(LaCluyze et al. GCNC 13764). A rapid photometric\nanalysis gives the following magnitudes:\n\nt0+Mid(s)  Rmag\n    159     16.5\n    200     16.3\n    281     15.8\n    351     15.9\n    451     16.2\n    652     16.6\n   1054     17.0\n\nWe measure an optical decay alpha=-1 from\nobservations after 300s, i.e. after the\noptical peak.\n\nConsidering the optical decay, optical\npredicted magnitudes are:\n\n2012-09-14T00:56 UT R=18.4 (t0+1h)\n2012-09-14T01:56 UT R=19.1 (t0+2h)\n2012-09-14T02:56 UT R=19.6 (t0+3h)\n2012-09-14T03:56 UT R=20.0 (t0+4h)\n2012-09-15T00:56 UT R=21.0 (t0+1day)\n\nThese predictions can help spectrometry\nobservations.",
  "circularId": 13766,
  "createdOn": 1347585367000,
  "email": "Alain.Klotz@free.fr",
  "subject": "GRB 120913B: TAROT La Silla observatory optical photometry",
  "submitter": "Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>",
  "eventId": "GRB 120913B"
}