{
  "bibcode": "2013GCN.14879....1C",
  "body": "S. B. Cenko (NASA/GSFC) and D. A. Perley report on behalf of a larger\ncollaboration:\n\nWe have imaged the field of the Swift GRB 130612A (Racusin et al., GCN\n14874) with the robotic Palomar 60 inch telescope.  Observations consist\nof individual 120 s frames in the g', r', i', and z' filters beginning at\n4:20 UT on 2013 June 12 (58 minutes after the Swift trigger).  The\noptical afterglow is detected in individual frames in all four\nfilters.  Using several nearby point sources from the USNO-B1 catalog for\nreference, we measure a magnitude of R = 20.8 at this time.",
  "circularId": 14879,
  "createdOn": 1371012961000,
  "email": "cenko@srl.caltech.edu",
  "subject": "GRB 130612A: P60 Observations",
  "submitter": "S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>",
  "eventId": "GRB 130612A"
}