{
  "bibcode": "2021GCN.29979....1W",
  "body": "Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H.\nLee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska\n(UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC), Owen\nLittlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jes��s Gonz��lez (UNAM), Carlos\nRom��n-Z����iga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou\n(U. Wash.), and Vicki Toy (UMD) report:\n\nWe observed the field of GRB 210509A (Page et al., GCN Circ. 29970) 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 2021/05 10.47 to 2021/05 10.48 UTC (19.34 to 19.70 hours after the BAT\ntrigger), obtaining a total of 0.21 hours exposure in the r and i bands and 0.08\nhours exposure in the Z, Y, J, and H bands.\n\nFor a source within the Swift-XRT error circle, in comparison with the SDSS DR9\nand 2MASS catalogs, we obtain the following upper limits (3-sigma):\n\n  r\t> 21.28\n  i\t> 21.09\n  Z\t> 18.17\n  Y\t> 19.19\n  J\t> 19.57\n  H\t> 17.30\n\nThese magnitudes are in the AB system and are not corrected for Galactic\nextinction in the direction of the GRB.",
  "circularId": 29979,
  "createdOn": 1620655886000,
  "email": "alan@astro.unam.mx",
  "subject": "GRB 210509A: RATIR Optical and NIR Upper Limits",
  "submitter": "Alan M Watson at UNAM  <alan@astro.unam.mx>",
  "eventId": "GRB 210509A"
}