{
  "bibcode": "2018GCN.23189....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 (U. Wash.), and Vicki Toy (UMD) report:\n\nWe observed the field of GRB 180828A (Beardmore, et al., GCN 23182) 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 2018/08 29.14 to 2018/08 29.28 UTC (8.29 to\n11.70 hours after the BAT trigger), obtaining a total of 1.73 hours\nexposure in the r and i bands and 0.79 hours exposure in the Z, Y, J, and H\nbands.\n\nWe find one uncatalogued source within the Swift-XRT error circle\n(Beardmore at at., GCN 23182) at RA, Dec = 17:54:52.5 -25:47:56.3 (J2000,\n+/-0.5\").  This source is outside the enhanced XRT error region (Evans et\nal., GCN 23184), within which we find no new sources.  In comparison with\nthe 2MASS catalog, we obtain the following detection and 3-sigma upper\nlimit:\n\n J > 21.4\n H = 20.8 +/- 0.3\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 has high\nextinction, with E[B-V]~16.\n\nWe thank the staff of the Observatorio Astron��mico Nacional in San Pedro\nM��rtir.",
  "circularId": 23189,
  "createdOn": 1535559243000,
  "email": "natbutler@asu.edu",
  "subject": "GRB 180828A: RATIR Optical and NIR Observations",
  "submitter": "Nat Butler at Az State U  <natbutler@asu.edu>",
  "eventId": "GRB 180828A"
}