{
  "editedOn": 1731008442026,
  "body": "Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William\nH. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB)\nJ. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UCSC),\nEleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC),\nJosé A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM),\nCarlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC)\nreport:\n\nWe observed the field of GRB 130418A (De Pasquale, et al., GCN 14377) with\nthe Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on\nthe 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional\non Sierra San Pedro Mártir from 2013/04 19.14 to 2013/04 19.19 UTC (8.24 to\n9.54 hours after the BAT trigger), obtaining a total of 1.07 hours exposure\nin the r' and i' bands and 0.45 hours exposure in the Z, Y, J, and H bands.\n\nFor a source within the Swift-UVOT error circle (Kuin et al., GCN 14384),\nin comparison with SDSS DR8 and 2MASS, we obtain the following detections\nin the AB magnitude system:\n\n r'    18.87 +/- 0.02\n i'    18.77 +/- 0.02\n Z    18.30 +/- 0.02\n Y    18.07 +/- 0.02\n J    18.06 +/- 0.02\n H    17.53 +/- 0.02\n\nThese magnitudes are not corrected for Galactic extinction in the direction\nof the GRB.  Relative to the GROND detections about 3 hrs earlier (Nardini\net al., GCN 14386), the afterglow has faded by about 0.4 mag in all\noptical/NIR bands.  Continued observations are planned.\n\nWe thank the staff of the Observatorio Astronómico Nacional in San Pedro\nMártir.",
  "version": 2,
  "createdOn": 1366349429000,
  "subject": "GRB 130418A: RATIR Optical and NIR Observations",
  "circularId": 14388,
  "submitter": "Nat Butler at UC berkeley  <natxbutler@gmail.com>",
  "editedBy": "Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>",
  "format": "text/plain",
  "eventId": "GRB 130418A",
  "bibcode": "2013GCN.14388....1B",
  "email": "natxbutler@gmail.com"
}