{
  "bibcode": "2010GCN.10471....1C",
  "body": "S. B. Cenko (UC Berkeley) reports on behalf of a larger collaboration:\n\nWe have imaged the field of GRB100305A (Troja et al., GCN 10470) with the\nautomated Palomar 60-inch telescope.  Images were obtained in the Sloan\ng', r', i', and z' filters beginning at 09:09 UT on 5 March 2010 (~ 3.5\nminutes after the burst).\n\nIn coadded images, we find no sources inside the XRT error circle to the\nfollowing limits (calculated with respect several point sources in the\nSDSS DR7 catalog):\n\nFilter\t\tMid-point\tt_burst\t\tExposure\tMagnitude\n-------------------------------------------------------------------------\nr'\t\t09:25\t\t19.5 min\t720.0\t\t> 22.0\nz'\t\t09:27\t\t21.7 min\t420.0\t\t> 20.5\ni'\t\t09:28\t\t23.3 min\t660.0\t\t> 22.0\n\nThe lack of an optical afterglow candidate, together with the long\nduration and lack of X-ray absorption in excess of the Galactic value\n(Troja et al., GCN 10470), make GRB100305A a candidate high redshift\nevent.  We encourage additional follow-up at longer wavelengths.",
  "circularId": 10471,
  "createdOn": 1267786117000,
  "email": "cenko@srl.caltech.edu",
  "subject": "GRB 100305A: P60 Observations",
  "submitter": "S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>",
  "eventId": "GRB 100305A"
}