[vsnet-grb-info 7143] GRB 081222: MITSuME optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8724
SUBJECT: GRB 081222: MITSuME optical observation
DATE:    08/12/25 01:51:58 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida at oao.nao.ac.jp>

D. Kuroda, 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 observed the field of GRB 081222 (Grupe et al. GCN 8691) with
the optical three color (g', Rc and Ic) imager attached to the
MITSuME 50cm telescope of Okayama Astrophysical Observatory on
Dec.22 2008 UT. We detected a fading point source at the position
of the X-ray - optical afterglow candidate (Covino et al. GCN 8692;
Updike et al. GCN8693; Grupe GCN 8705) in Rc band. Photometric
results are listed below. We used GSC2.3 catalog for flux
calibration.

# Mid-MJD      Mid-UT   EXP-T    g'       Rc          Ic
-------------------------------------------------------------
54822.401100  09:37:36  540.0  >18.3  18.0+/-0.3  >17.8
54822.438455  10:31:23 2940.0  >19.2  18.9+/-0.3  >18.2
54822.469650  11:16:18 4500.0  >19.2  19.3+/-0.4  18.6+/-0.3
-------------------------------------------------------------