{
  "bibcode": "2015GCN.17920....1S",
  "body": "Y.Saito, T.Fujiwara, T. Yoshii, Y. Tachibana, H. Ohuchi, Y. Yano,\nS. Kurita, Y.Ono, S.Harita, Y.Muraki, Y. Yatsu, and N. Kawai (Tokyo Tech)\nreport on behalf of the MITSuME collaboration:\n\nWe observed the field of GRB 150608A (M.Arimoto et al., GCN Circular #17912) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.\n\nThe observation started on 2015-06-09 18:17:37 UT (~30.5 h after the burst). We cound not detect any optical point source in the error circle of the previously reported afterglow detected by Swift-XRT (M.G.Bernardini et al., GCN Circular #17917) in all three bands.\n\nThree sigma upper limits are listed below.\n\nT0+[hour]      MID-UT      T-EXP[sec]         g'           Rc           Ic\n---------------------------------------------------------------------------------------\n  30.5131     18:23:03          600            > 17.9     > 18.0     > 17.4\n---------------------------------------------------------------------------------------\nT0+ : Elapsed time after the burst\nT-EXP: Total Exposure time\nWe used GSC2.3 catalog for flux calibration",
  "circularId": 17920,
  "createdOn": 1434085224000,
  "email": "yoshii.t.ac@m.titech.ac.jp",
  "subject": "GRB 150608A: MITSuME Akeno optical upper limits",
  "submitter": "Taketoshi Yoshii at Tokyo Tech  <yoshii.t.ac@m.titech.ac.jp>",
  "eventId": "GRB 150608A"
}