{
  "bibcode": "2021GCN.30973....1W",
  "body": "Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H.\nLee (UNAM), Eleonora Troja (GSFC), Michael G. Richer (UNAM), Ori Fox (STScI), J.\nXavier Prochaska (UCSC), Josh Bloom (UCB), Enrico Ramirez-Ruiz (UCSC), Jes��s\nGonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey Moseley (GSFC), Rosa L.\nBecerra (UNAM), Simone Dichiara (UMD), and Oc��lotl L��pez (UNAM) report:\n\nWe observed the field of GRB 211023B (Dichiara et al., GCN 30960) with the\nReionization and Transients Infrared Camera (RATIR) on the 1.5m Harold Johnson\nTelescope at the Observatorio Astron��mico Nacional on Sierra San Pedro M��rtir\nfrom 2021/10 24.49 to 2021/10 24.53 UTC (14.54 to 15.54 hours after the BAT\ntrigger), obtaining a total of 0.73 hours exposure in the r and i bands and 0.30\nhours exposure in the Z, Y, J, and H bands.\n\nFor a source within the UVOT error circle, in comparison with the SDSS DR9 and\n2MASS catalogs, we obtain the following detections and upper limits (3-sigma):\n\n  r\t> 22.4\n  i\t> 22.1\n  Z\t> 20.6\n  Y\t> 20.3\n  J\t> 21.0\n  H\t> 20.7\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 M��rtir.",
  "circularId": 30973,
  "createdOn": 1635086097000,
  "email": "alan@astro.unam.mx",
  "subject": "GRB 211023B: RATIR Optical and NIR Upper Limits",
  "submitter": "Alan M Watson at UNAM  <alan@astro.unam.mx>",
  "eventId": "GRB 211023B"
}