{
  "bibcode": "2010GCN.11073....1C",
  "body": "S. B. Cenko (UC Berkeley) reports on behalf of a larger collaboration:\n\nWe have imaged the field of GRB 100807A (Grupe et al., GCN 11067) with the\nautomated Palomar 60 inch telescope.  Observations were obtained in the\nSloan r', i', and z' filters beginning at 9:16 UT on 7 August (~ 3 min\nafter the Swift trigger).\n\nAt the edge of the enhanced XRT position (Osborne et al., GCN 11070), we\ndetect a fading point source with coordinates (J2000.0):\n\n\tRA: 03:41:12.43    Dec: +67:40:17.4\n\nUsing several nearby objects in the USNO-B1 catalog for reference, we\nreport the following photometry for this object:\n\nUT (mid-point)\tt_burst (min)\tFilter\t\tMagnitude\n---------------------------------------------------------------\n09:16:55\t3.7\t\tR\t\t20.47 +/- 0.17\n09:18:21\t5.1\t\tI\t\t19.80 +/- 0.14\n09:47:07\t33.9\t\tR\t\t21.57 +/- 0.20\n09:49:58\t36.8\t\tI\t\t20.96 +/- 0.20\n\nThe above magnitudes have not been corrected for the large Galactic\nextinction along the line of sight.\n\nThe fading behavior confirms this source is the optical afterglow of GRB\n100807A.",
  "circularId": 11073,
  "createdOn": 1281214556000,
  "email": "cenko@srl.caltech.edu",
  "subject": "GRB 100807A: P60 Optical Afterglow Discovery",
  "submitter": "S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>",
  "eventId": "GRB 100807A"
}