[vsnet-grb-info 17367] GRB 151228A: MITSuME Akeno optical upper limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18747
SUBJECT: GRB 151228A: MITSuME Akeno optical upper limits
DATE:    15/12/29 09:15:22 GMT
FROM:    Taketoshi Yoshii at Tokyo Tech  <yoshii.t.ac at m.titech.ac.jp>

Y.Saito, T.Fujiwara, T. Yoshii, Y. Tano, Y. Tachibana,
Y.Ono, S.Harita, Y.Muraki, Y. Yatsu, and N. Kawai (Tokyo Tech)

report on behalf of the MITSuME collaboration:

We searched for the optical counterpart of GRB 151228A (T. N. Ukwatta et al., GCN Circular #18731) with the
optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.

The observation started on 2015-12-28 19:25:49 UT (~16.3 h after the burst).
We did not find any new point source within BAT circle in all three bands.

We obtained following limits for the magnitudes.

T0+[sec]       MID-UT     T-EXP[sec]      g'        Rc             Ic
--------------------------------------------------------------------------------------
58837         20:04:32      4200         > 20.0     > 20.0     > 19.3
---------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.