{
  "bibcode": "2018GCN.23481....1W",
  "body": "Alan M. Watson (UNAM), Margarita Pereyra (UNAM), Nat Butler (ASU), Rosa\nL. Becerra (UNAM), William H. Lee (UNAM), Carlos Rom��n-Z����iga (UNAM),\nAlexander Kutyrev (GSFC), and Eleonora Troja (GSFC), report:\n\nWe observed the field of GRB 181201A (Mereghetti et al., GCN 23469) with\nthe COATLI 50-cm telescope and interim imager at the Observatorio\nAstron��mico Nacional on the Sierra de San Pedro M��rtir\n(http://coatli.astroscu.unam.mx) from 2018-12-02 01:39:01 to 04:02:58\n(from 23.0 to 25.4 hours after the trigger), obtaining a total of 1.89\nhours of exposure in the w filter.\n\nWe detect the optical counterpart reported by Podesta et al. (GCN Circ.\n23470) at w = 17.82 +/- 0.01.\n\nOur w magnitudes are calibrated against the USNO-B1 catalog (adjusted to\nan approximate AB system) and are not corrected for Galactic extinction\nin the direction of the GRB.\n\nWe thank the COATLI technical team (Fernando ��ngeles, Oscar Chapa,\nSalvador Cuevas, Alejandro Farah, Jorge Fuentes, Rosal��a Langarica,\nFernando Quir��s, and Carlos Tejada) and the staff of the Observatorio\nAstron��mico Nacional.",
  "circularId": 23481,
  "createdOn": 1543732662000,
  "email": "alan@astro.unam.mx",
  "subject": "GRB 181201A: COATLI Optical Detection",
  "submitter": "Alan M. Watson at Instituto de Astronomia UNAM  <alan@astro.unam.mx>",
  "eventId": "GRB 181201A"
}