{
  "bibcode": "1999GCN...295....1Z",
  "body": "J. Zhu, H. T. Zhang, on behalf of the BAO GRB follow-up team, report:\n\n\"Observations of the GRB 990506 field were made with the BAO 0.6/0.9m\nSchmidt telescope in Xinglong from 1 hour and 10 minutes after the GRB,\nusing R-band filter and 2k x 2k CCD. The 16 observation fields (each of\n58' x 58') covered 3.6 degrees x 3.6 degrees field centered at the\nBACODINE/HUNTSVILLE/LOCBURST position, so it contains the IPN/RXTE box\nannounced later in (GCN 291) by Hurley and Barthelmy. Observations\nfor that area were made by two 300s exposures at 12:41:47 UT and 14:41:38 UT\nrespectively (about 1 and 3 hours after the GRB), and comparison with DSS-I\nimage shows no additional source (appeared in both of the two images we\nmade) in a detection limit of about R=19.0. No source could be seen at the\nposition of F.J. Vrba et. al (GCN 294). Data reduction was delayed by\nelectral power failure in observation site, and wider part around that area\nwill be checked later.\n\nThis report may be cited.\"",
  "circularId": 295,
  "createdOn": 926063656000,
  "email": "grb@bac.pku.edu.cn",
  "subject": "GRB 990506, optical observations from +1 to +3 hours",
  "submitter": "Jin Zhu at Beijing Obs  <grb@bac.pku.edu.cn>",
  "eventId": "GRB 990506"
}