{
  "bibcode": "2018GCN.23396....1W",
  "body": "Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),\nWilliam H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.\nXavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),\nEleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz\n(UCSC), Jes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey\nMoseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki\nToy (UMD) report:\n\nWe observed the field of GRB 181030A (Sonbas et al., GCN Circ. 23389)\nwith the Reionization and Transients Infrared Camera (RATIR;\nwww.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio\nAstron��mico Nacional on Sierra San Pedro M��rtir from 2018/10 30.41 to\n2018/10 30.53 UTC (8.40 to 11.29 hours after the BAT trigger), obtaining\na total of 0.82 hours exposure in the r and i bands and 0.39 hours\nexposure in the Z, Y, J, and H bands.\n\nFor a source within the XRT error circle, in comparison with the SDSS\nDR9 and 2MASS catalogs, we obtain the following upper limits (3-sigma):\n\n  r\t> 22.25\n  i\t> 22.11\n  Z\t> 21.07\n  Y\t> 20.80\n  J\t> 20.31\n  H\t> 19.61\n\nThese magnitudes are in the AB system and are not corrected for Galactic\nextinction in the direction of the GRB.\n\nThe afterglow has clearly faded since the early observations of Sonbas\net al. (GCN Circ. 23389), Moskvitin & Spiridonova (GCN Circ. 23390), and\nLipunov et al. (GCN Circ. 23392).\n\nWe thank the staff of the Observatorio Astron��mico Nacional in San Pedro\nM��rtir.",
  "circularId": 23396,
  "createdOn": 1540914966000,
  "email": "alan@astro.unam.mx",
  "subject": "GRB 181030A: RATIR Optical and NIR Observations",
  "submitter": "Alan M. Watson at Instituto de Astronomia UNAM  <alan@astro.unam.mx>",
  "eventId": "GRB 181030A"
}