{
  "bibcode": "2020GCN.27215....1P",
  "body": "Margarita Pereyra (UNAM), Nat Butler (ASU), Alan M. Watson (UNAM),\nEleonora Troja (GSFC/UMD), Simone Dichiara (GSFC/UMD), Rosa L. Becerra\n(UNAM), William H. Lee (UNAM), Diego Gonzalez (UNAM), Alexander Kutyrev\n(GSFC/UMD), and Tanner Wolfram (ASU), report:\n\nWe observed the field of GRB 200224B detected by the Fermi Gamma-ray Burst\nMonitor (GCN 27174, Fermi trigger 604213554), with the DDOTI/OAN wide-field\nimager at the Observatorio Astron��mico Nacional on Sierra San Pedro M��rtir (\nhttp://ddoti.astroscu.unam.mx) from 2020-02-24 06:47 to 2020-02-24 12:16\nUTC (1.68 to 7.16 hours after the event).\n\nWe observed a region of 13.6 degrees in RA by 20.4 degrees in declination,\nwith a 2 x 2 grid, centered on the Fermi GBM Final Position +11:51:36\n-28:52:11 J2000. This region contains about 277 square degrees. We obtained\n2040 to 2520 seconds exposure across the region. We calibrated our images\nagainst the APASS catalog. Our 10-sigma limiting magnitude is around w =\n19.45.\n\nComparing to the USNO-B1, DSS DR2 and Pan-STARRS DR1 catalogs, we do not\ndetect any uncataloged source with significant fading within the 90%\nprobability radius of 6.3 degrees.\n\nWe thank the staff of the Observatorio Astron��mico Nacional in San Pedro\nM��rtir.\n\n\n-- \n*Dr. Margarita Pereyra *\n\n*FFTF, Schlumberger Foundation Alumnae*\n----------------------------------------------------------------------------------------------------------------\n\n*Catedr��tico Conacyt*\n\n*Instituto de Astronom��a de la UNAM,*\n\n*Km. 107 Carretera Tijua**na-Ensenada, *\n\n*Ensenada Baja California, M��xico. C.P. 22860*\n\nOficina: 405\n\nSkype: margarita-pereyra",
  "circularId": 27215,
  "createdOn": 1582677012000,
  "email": "mpereyra@astro.unam.mx",
  "subject": "GRB 200224B: DDOTI/OAN optical observations report",
  "submitter": "Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra@astro.unam.mx>",
  "eventId": "GRB 200224B"
}