{
  "bibcode": "2012GCN.13046....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 120311B (Marshall et al., GCNC 13038)\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 2012-03-11 16:48:04 UT (~1.7 h after the burst)\nWe did not find any new point source within the enhanced XRT circle\n(Osborne et al., GCNC 13042) in all the three bands.\n\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------------------------------------------------------\n0.09146    17:19:52    4380.0   >18.7  >18.8  >18.3\n0.15451    18:50:40    4740.0   >19.6  >19.6  >18.9\n------------------------------------------------------\nT0+ : Elapsed time after the burst [day]\nT-EXP: Total Exposure time [sec]",
  "circularId": 13046,
  "createdOn": 1331543689000,
  "email": "dikuroda@oao.nao.ac.jp",
  "subject": "GRB 120311B: MITSuME Okayama Optical upper limits",
  "submitter": "Daisuke Kuroda at OAO/NAOJ  <dikuroda@oao.nao.ac.jp>",
  "eventId": "GRB 120311B"
}