{
  "bibcode": "2017GCN.20915....1B",
  "body": "Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William\nH. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier\nProchaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora\nTroja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jes��s\nGonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey Moseley (GSFC), John\nCapone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report:\n\nWe observed the field of GRB 170318A (Sbarufatti, et al., GCN 20904) with\nthe Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on\nthe 1.5m Harold Johnson Telescope at the Observatorio Astron��mico Nacional\non Sierra San Pedro M��rtir from 2017/03 18.51 to 2017/03 18.53 UTC (3.0 to\n27.6 minutes after the BAT trigger), obtaining a total of 0.24 hours\nexposure in the r and i bands and 0.11 hours exposure in the Z, Y, J, and H\nbands.\n\nWe do not detect a source within the Swift-XRT error circle (Evans, et al.,\nGCN 20907).  In comparison with the USNO-B1 and 2MASS catalogs, we obtain\nthe following upper limits (3-sigma):\n\n r > 23.39\n i > 22.82\n Z > 21.72\n Y > 21.56\n J > 21.12\n H > 20.73\n\nThese magnitudes are in the AB system and are not corrected for Galactic\nextinction in the direction of the GRB.  We note that this field suffers\nlarge Galactic extinction (A_V~3).\n\nWe thank the staff of the Observatorio Astron��mico Nacional in San Pedro\nM��rtir.",
  "circularId": 20915,
  "createdOn": 1489874917000,
  "email": "natbutler@asu.edu",
  "subject": "GRB 170318A: RATIR Optical and NIR Observations",
  "submitter": "Nat Butler at Az State U  <natbutler@asu.edu>",
  "eventId": "GRB 170318A"
}