{
  "bibcode": "2007GCN..6531....1Y",
  "body": "M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama (OAO, NAOJ)\nand N. Kawai (Tokyo Tech) report on behalf of the MITSuME\ncollaboration:\n\nWe performed optical imaging observations (Rc and Ic) of the\nfield of GRB 070612A (Grupe et al., GCN 6509) with 50cm MITSuME\ntelescope at Okayama Astrophysical Observatory from UT 11:19 to\nUT 11:27 on June 12 2007.\n\nWe coadded 4 CCD frames for each band. Exposure time of each\nframe is 1 minute. We made flux calibration using USNO B1.0\ncatalg. We found a faint source at the position of the afterglow\ncandidate reported by Cenko et al. (GCN 6525, RA:08:05:29.6,\nDEC:+37:16:15) in Ic band. The Ic magnitude was 17.1 +/- 0.3.\nThere was no source brigher than 16.7 magnitude in Rc band. Flux\ncalibration was made with three USNO-B stars around the object.\n\n---------------------------------------------------------------\nband  mid-UT          exp.time     magnitude\nRc    June 12 11:23   4 x 1 min.   > 16.7 mag (upper limit)\nIc    June 12 11:34   4 x 1 min.   17.1 mag +/- 0.3 mag\n---------------------------------------------------------------",
  "circularId": 6531,
  "createdOn": 1181777129000,
  "email": "yoshida@oao.nao.ac.jp",
  "subject": "GRB070612A: MITSuME Okayama Observation",
  "submitter": "Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida@oao.nao.ac.jp>",
  "eventId": "GRB 070612A"
}