{
  "bibcode": "2009GCN..8933....1C",
  "body": "S. B. Cenko, B. E. Cobb, D. A. Perley, and J. S. Bloom (UC Berkeley)\nreport on behalf of a larger collaboration:\n\nWe have imaged the field of the short GRB 090305 (Beardmore et al., GCN\n8932) with GMOS mounted on the Gemini South telescope beginning\napproximately 27 minutes after the burst.  Observations were taken in\nthe Sloan g', r', and i' filters and cover nearly the entire BAT error\ncircle.\n\nInside the BAT error circle, we find a fading point source at the location\n(J2000.0):\n\n   RA: 16:07:07.61\n   Dec: -31:33:21.9\n\nCalibrating with respect to the USNO-B1 object at 16:07:06.58, -31:33:37.9\n(R2=18.99), we measure an initial magnitude of R ~ 23.3.  The source fades\nby approximately 1.1 mag over the next two hours, corresponding to a\npower-law decay index of ~ 0.6 (assuming no contribution from an\nunderlying host galaxy).  At this point we tentatively consider this\nsource the afterglow of GRB090305, although we await confirmation from the\nXRT.\n\nWe wish to thank the staff at Gemini South, in particular Peter Pessev,\nfor performing our target of opportunity observations.",
  "circularId": 8933,
  "createdOn": 1236249167000,
  "email": "cenko@srl.caltech.edu",
  "subject": "GRB090305: GMOS-S Candidate Optical Afterglow",
  "submitter": "S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>",
  "eventId": "GRB 090305"
}