{
  "bibcode": "2006GCN..4636....1C",
  "body": "S. B. Cenko, D.-S. Moon, (Caltech), and B. P. Schmidt (MSO-ANU) report on\nbehalf of a larger collaboration:\n\nWe have imaged the field GRB060202 (Fox et al., GCN 4629) with the\nLow-Resolution Imaging Spectrometer mounted on the 10-m Keck I telescope.\nObservations consisted of 2 x 300 s images taken simultaneously in the\ng and I filters at a mean time of approximately February 3.22.  Images\nwere taken under good seeing conditions, though shortly after sunset with\na high background.\n\nInside the revised XRT error circle (Morris et al., GCN 4632), we find one\nfaint source (S1) in our I-band images detected at approximately the\n2-sigma level.  The location of this source is (J2000):\n\n\tRA: 02:23:22.88\n\tDec: +38:23:04.3\n\nwith an approximate error of 1.0\" in each coordinate.  The magnitude of\nthis object, with reference to the USNO-B2 catalog, is approximately I =\n22.6 +/- 0.3, with photometric calibration dominating the errors.  We find\nno source in our g-band coadd at this location to a limiting magnitude of\napproximately g > 22.0.  We note this position is consistent with the\ndetection of a K-band source with UKIRT by Wang et al. (private\ncommunication, GCN forthcoming).\n\nThere is one additional source (S2), of similar magnitude and color,\nlocated just outside the edge of the XRT error circle, which we include\nfor completeness.  The location of this source (J2000.0) is:\n\n\tRA: 02:23:22.80\n\tDec: +38:23:08.9\n\nWhile we cannot comment on variability at this time, we propose that the\nsource S1 is the afterglow of GRB 060202.\n\nThe early R-band limits provided by Monfardini et al. (GCN 4630) indicate\na red R-I color for this potential afterglow.  Given the possibility that\nthis object is at high redshift (z > 5), we have triggered Gemini NIR\nimaging of the field.  A report on these observations will follow in\na subsequent GCN.",
  "circularId": 4636,
  "createdOn": 1138958600000,
  "email": "cenko@srl.caltech.edu",
  "subject": "GRB 060202: Optical Afterglow Candidate from Keck/LRIS",
  "submitter": "S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>",
  "eventId": "GRB 060202"
}