[vsnet-grb-info 17266] GRB 151118A: MITSuME Akeno optical upper limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18630
SUBJECT: GRB 151118A: MITSuME Akeno optical upper limits 
DATE:    15/11/21 08:27:02 GMT
FROM:    Taketoshi Yoshii at Tokyo Tech  <yoshii.t.ac at m.titech.ac.jp>

Y.Yano, T.Fujiwara, T. Yoshii, Y. Saito, 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 151118A (A. Amaral–Rogers et al., GCN Circular #18611) 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 2015-11-18 19:14:09 UT (~16.1 h after the burst).
We did not find any new point source within XRT circle in all three bands.

We obtained following limits for the magnitudes.

T0+[sec] MID-UT T-EXP[sec] g' Rc Ic
-------------------------------------------------------------
58059  19:44:17  2520  > 20.3  > 19.6  > 18.4
-------------------------------------------------------------
T0+ : Elapsed time after the burst 
T-EXP: Total Exposure time 
We used GSC2.3 catalog for flux calibration.