{
  "bibcode": "2014GCN.16640....1S",
  "body": "L. P. Singer (Caltech), S. B. Cenko (NASA/GSFC), and M. M. Kasliwal\n(Carnegie Observatories/Princeton) report on behalf of the\nintermediate Palomar Transient Factory (iPTF) collaboration:\n\nWe searched for optical counterparts of GRB 140729A (Arimoto, GCN 16633;\nBissaldi, GCN 16635; Stanbro, GCN 16636) using the Palomar 48-inch\nOschin telescope (P48). Based on the final Fermi GBM localization\nwith a 1-sigma statistical radius of 1.57 deg, we imaged 10 fields\ncovering an area of 73 deg2. These fields also contained all of the\nFermi LAT error circle and its intersection with the IPN annulus\n(Svinkin, GCN 16637).\n\nIn our observations on 2014-07-29 from 04:05:50 to 04:51:48 UT (3.48\nto 4.5 hours after the burst), we find no plausible optical afterglow\ncandidates within the LAT error circle, to a limiting magnitude of\nR=20.6.\n\nThe diagram http://www.its.caltech.edu/~lsinger/iptf/Fermi428287016.pdf\nshows the locations of our ten P48 fields in relation to the Fermi\nGBM 1- and 2-sigma statistical+systematic contours as well as the LAT\nerror circle and the IPN annulus.",
  "circularId": 16640,
  "createdOn": 1406694760000,
  "email": "lsinger@caltech.edu",
  "subject": "GRB 140729A: iPTF optical upper limit",
  "submitter": "Leo Singer at CIT/PTF  <lsinger@caltech.edu>",
  "eventId": "GRB 140729A"
}