{
  "bibcode": "2020GCN.26977....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 200131A (Sbarufatti et al., GCN 26953) with\nthe Reionization and Transients Infrared Camera (RATIR; www.ratir.org)\non the 1.5m Harold Johnson Telescope at the Observatorio Astron��mico\nNacional on Sierra San Pedro M��rtir from 2020/02 2.10 to 2020/02 2.17\nUTC (27.70 to 29.45 hours after the BAT trigger), obtaining a total of\n1.42 hours exposure in the r and i bands, and from 2020/02 3.10 to\n2020/02 3.12 UTC (51.69 to 52.28 hours after the BAT trigger), obtaining\na total of 0.49 hours exposure in the r and i bands.\n\nThe optical transient (Lipunov et al., GCN Circ. 26954, Butler et al.,\nGCN Circ. 26957, Strausbaugh et al., GCN Circ. 26959, Gokuldass et al.,\nGCN Circ. 26960, Pozanenko et al., GCN Circ. 26964 & 26965) is detected\non 2020/02/02 with:\n\n  r = 21.39 +/- 0.11\n  i = 21.39 +/- 0.07\n\nand on 2020/02/03 with:\n\n  r = 22.26 +/- 0.29\n  i = 22.45 +/- 0.35\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": 26977,
  "createdOn": 1580757728000,
  "email": "natbutler@asu.edu",
  "subject": "GRB 200131A: Further RATIR Optical Observations",
  "submitter": "Nat Butler at Az State U  <natbutler@asu.edu>",
  "eventId": "GRB 200131A"
}