{
  "bibcode": "2013GCN.14643....1W",
  "body": "Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),\nWilliam H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB),\nOri Fox (UCB) J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino\nCucchiara (UCSC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico\nRamirez-Ruiz (UCSC), Jos�� A. de Diego (UNAM), Leonid Georgiev (UNAM),\nJes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Neil Gehrels (GSFC),   \nand Harvey Moseley (GSFC) report:\n\nWe observed the field of GRB 130514A (Sonbas et al., GCN 14632) with the\nReionization and Transients Infrared Camera (RATIR; www.ratir.org) on the\n1.5m Harold Johnson Telescope at the Observatorio Astron��mico Nacional on\nSierra San Pedro M��rtir from 2013/05 14.30 to 2013/05 14.46 UTC (4.7 minutes\nto 3.90 hours after the BAT trigger), obtaining a total of 2.49 hours\nexposure in the r' and i' bands and 1.04 hours exposure in the Z,\nY, J, and H bands.\n\nFor a source within the Swift-XRT error circle, in comparison with USNO-B1\nand 2MASS, we obtain the following upper limits (3-sigma):\n\n  r' > 23.51\n  i' > 23.39\n  Z  > 22.07\n  Y  > 21.62\n  J  > 21.43\n  H  > 21.13\n\nThese magnitudes are in the AB system and not corrected for Galactic\nextinction in the direction of the GRB.\n\nSchmidl et al. (GCN Circular 14634) report a source with r = 20.0 and i =\n19.2 in images taken from 2 to 6 minutes after the BAT trigger. Perley\n(GCN Circular 14633) reports a marginal detection in r and z in images\ntaken from 12 to 27 minutes after the BAT trigger. We began exposing on\nthis field less than 5 minutes after the BAT trigger, but due to the\nhigh airmass of almost 5 and poor transparency on the south-eastern\nhorizon, our first useful images are not until about 17 minutes after\nthe trigger. The evolution of our 3-sigma limits is:\n\n  i' > 21.72 at 0.49 hours after the trigger   \n  i' > 22.48 at 1.14 hours\n  i' > 23.00 at 1.59 hours\n  i' > 23.17 at 2.02 hours\n  i' > 23.24 at 2.60 hours\n  i' > 23.30 at 3.34 hours\n  i' > 23.39 at 3.90 hours\n\nIf we extrapolate the Schmidl et al. measurement of i = 19.2 at 4 minutes\naccording to t^-1, we would expect to have detected their source in our\nobservations out to 2 hours. That we did not suggests that light curve\nfell faster than this. We note that quick-look light curve for Swift-XRT\nfalls by almost three orders of magnitude between about 3 minutes and 20\nminutes, which may be consistent with a rapid optical decay.\n\nWe thank the staff of the Observatorio Astron��mico Nacional in San Pedro\nM��rtir.\n\n[GCN OPS NOTE(14may13): Per author's request,\"Kann et al\" was changed\nto \"Schmidl et al\", and the \"approx equal\" ISO-char symbols were replaced\nwith simple equal signs (=).]",
  "circularId": 14643,
  "createdOn": 1368555186000,
  "email": "alan@astro.unam.mx",
  "subject": "GRB 130514A: RATIR Optical and NIR Observations",
  "submitter": "Alan M. Watson at Instituto de Astronomia UNAM  <alan@astro.unam.mx>",
  "eventId": "GRB 130514A"
}