{
  "bibcode": "2018GCN.22582....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\nRamirez-Ruiz (UCSC), Jes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM),\nHarvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and\nVicki Toy (UMD) report:\n\nWe observed the field of GRB 180402A (Lien, et al., GCN 22580) 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 2018/04 2.41 to 2018/04 2.50 UTC (1.8 minutes\nto 2.33 hours after the BAT trigger), obtaining a total of 1.76 hours\nexposure in the r and i bands.\n\nFor a source within the Swift-XRT error circle, in comparison with the\nUSNO-B1 catalog, we obtain the following upper limits (3-sigma):\n\n  r > 23.3\n  i > 23.3\n\nThese magnitudes are in the AB system and are not corrected for Galactic\nextinction in the direction of the GRB.\n\nWe thank the staff of the Observatorio Astron��mico Nacional in San Pedro\nM��rtir.",
  "circularId": 22582,
  "createdOn": 1522684306000,
  "email": "natbutler@asu.edu",
  "subject": "GRB 180402A: RATIR Upper Limits",
  "submitter": "Nat Butler at Az State U  <natbutler@asu.edu>",
  "eventId": "GRB 180402A"
}