TITLE:   GCN CIRCULAR
NUMBER:  10388
SUBJECT: GRB100206: MITSuME optical upper limits
DATE:    10/02/07 02:15:59 GMT
FROM:    Daisuke Kuroda at OAO/NAOJ  <dikuroda@oao.nao.ac.jp>

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

We observed the field of GRB 100206A (Krimm et al. GCN 10376)
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 2010-02-06 13:31:10 UT (65s after the
burst). We did not find any new point source in the XRT error
circle in all the three bands.

Three sigma upper limits of the OT are listed below. We used
GSC2.3 catalog for flux calibration.

PDAY     MID-UT    T-EXP    g'     Rc     Ic
---------------------------------------------------
0.00422  13:36:10   480.0 >19.0  >19.0  >17.9
0.02166  14:01:17  2940.0 >19.8  >19.8  >18.7
---------------------------------------------------