{
  "bibcode": "2008GCN..7370....1Y",
  "body": "M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama, H. Toda\n(OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf of the\nMITSuME collaboration:\n\nWe performed optical imaging observations (g', Rc, and Ic) of\nthe field of GRB 080307 (Holland et al. GCN 7362) with the\n50cm MITSuME telescope at Okayama Astrophysical Observatory\nfrom UT 11:25:50 to UT 12:47:00 on March 7 2008.\n\nFlux calibration was made using USNO B1.0 catalog. We could\nnot identify any new source at the XRT position (Holland et al.\nGCN 7362) or the UVOT positions (Schady et al. GCN 7367).\nThree sigma upper limits are listed below.\n\nmid-UT                exp.time     g'     Rc      Ic\n-------------------------------------------------------\n2008-03-07 11:31:20    10 min.   >19.6   >19.3   >18.7\n2008-03-07 12:12:00    57 min.   >20.5   >20.3   >19.5\n-------------------------------------------------------",
  "circularId": 7370,
  "createdOn": 1204905594000,
  "email": "yoshida@oao.nao.ac.jp",
  "subject": "GRB080307: Optical upper limits",
  "submitter": "Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida@oao.nao.ac.jp>",
  "eventId": "GRB 080307"
}