[vsnet-grb-info 21518] GRB 190106A: MITSuME Akeno optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23617
SUBJECT: GRB 190106A: MITSuME Akeno optical observation
DATE:    19/01/06 14:36:58 GMT
FROM:    Ryosuke Itoh at Tokyo Institute of Tech.  <itoh at hp.phys.titech.ac.jp>

R. Itoh, K. L. Murata, Y. Tachibana, S. Harita, K. Morita,
K. Shiraishi, K. Iida, M. Niwano, R. Adachi, M. Oeda,  Y. Yatsu,
and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration

We searched for the optical counterpart of GRB 190106A (Sonbas et al., GCN
Circular #23615) with the optical three color (g', Rc, and Ic) CCD cameras
attached to the MITSuME 50cm telescope of Akeno Observatory, Yamanashi, Japan.

The observation started on 13:35:33 UT which corresponds to
49 sec after the trigger.
We detected the point source at the position consistent with the Swift/UVOT
observation (Sonbas et al., GCN Circular #23615) and MASTER
observation (Lipunov et al., GCN Circular #23616).
The measured magnitudes are listed as follows.

T0+[sec]    MID-UT      T-EXP[sec]        g'       Rc        Ic
-------------------------------------------------------------------------------------------------------
~49      13:36:02.6           60               ~16.1      ~15.6   ~15.5
-------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used UCAC-4 catalog for flux calibration.
The magnitudes are expressed in the AB system.

Further analysis is ongoing.