[vsnet-grb-info 5404] GRB071112C MITSuME Okayama Optical Observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7082
SUBJECT: GRB071112C MITSuME Okayama Optical Observation
DATE:    07/11/13 23:06:45 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida at oao.nao.ac.jp>

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

We performed optical imaging observations (G, Rc and Ic) of the field of
GRB 071112C (Perri et al., GCN 7059) with 50cm MITSuME telescope at
Okayama Astrophysical Observatory from UT 18:35 to UT 19:52 on November
12 2007.

We found a fading source at the position of the optical afterglow
reported by several authors (Yuan et al., GCN 7061; Wang et al., GCN
7063; Burenin et al., GCN 7066; Chen et al., GCN 7067; Sollerman et al.,
GCN 7070) in all bands. We made flux calibration using USNO B1.0
catalog. The photometric results are following.

start-T   end-T     mid-T     exp-T  G          Rc         Ic
---------------------------------------------------------------------
18:35:34  18:36:34  18:36:04   1min  17.1+-0.1  17.0+-0.1  17.9+-0.1
18:35:34  18:39:00  18:37:17   3min  17.2+-0.1  17.2+-0.1  18.0+-0.1
18:39:12  18:45:09  18:42:10   5min  17.9+-0.1  18.0+-0.1  18.6+-0.1
18:45:19  18:56:20  18:50:49   7min  18.8+-0.2  18.5+-0.2  19.6+-0.2
18:56:30  19:08:46  18:32:38  10min  19.3+-0.4  19.0+-0.2  >19.8
19:08:56  19:57:01  19:32:58  40min  >19.5      19.6+-0.2  >20.0
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