{
  "bibcode": "2012GCN.13817....1K",
  "body": "D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ),\nS. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)\nand N. Kawai(Tokyo Tech)\nreport on behalf of the MITSuME collaboration:\n\nWe observed the field of GRB 120923A (Yershov et al., GCNC 13796)\nwith the optical three color (g', Rc and Ic) CCD camera attached\nto the MITSuME 50cm telescope of Okayama Astrophysical Observatory.\n\nThe observation started on 2012-09-23 10:00:39 UT (~4.7 h after the burst)\nWe did not find any new point source within the enhanced XRT circle\n(Goad et al., GCNC 13801) in all the three bands.\nWe also could not detect the previously reported afterglow (Levan et al.,\nGCNC 13802).\n\nThree sigma upper limits of the OT are listed below. We used\nSDSS catalog for flux calibration.\n\nT0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic\n------------------------------------------------------\n0.23958    11:01:05    6360.0   >20.6  >20.2  >18.9\n------------------------------------------------------\nT0+ : Elapsed time after the burst [day]\nT-EXP: Total Exposure time [sec]",
  "circularId": 13817,
  "createdOn": 1348552487000,
  "email": "dikuroda@oao.nao.ac.jp",
  "subject": "GRB 120923A: MITSuME Okayama Optical upper limits",
  "submitter": "Daisuke Kuroda at OAO/NAOJ  <dikuroda@oao.nao.ac.jp>",
  "eventId": "GRB 120923A"
}