[vsnet-grb-info 11653] GRB 120311B: MITSuME Okayama Optical upper limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13046
SUBJECT: GRB 120311B: MITSuME Okayama Optical upper limits
DATE:    12/03/12 09:14:49 GMT
FROM:    Daisuke Kuroda at OAO/NAOJ  <dikuroda at oao.nao.ac.jp>

D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ),
S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME collaboration:

We observed the field of GRB 120311B (Marshall et al., GCNC 13038)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.

The observation started on 2012-03-11 16:48:04 UT (~1.7 h after the burst)
We did not find any new point source within the enhanced XRT circle
(Osborne et al., GCNC 13042) in all the three bands.


Three sigma upper limits of the OT are listed below. We used
SDSS catalog for flux calibration.

T0+[day]   MID-UT   T-EXP[sec]    g'     Rc     Ic
------------------------------------------------------
0.09146    17:19:52    4380.0   >18.7  >18.8  >18.3
0.15451    18:50:40    4740.0   >19.6  >19.6  >18.9
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]