[vsnet-grb-info 23920] GRB191016A: MITSuME Okayama optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26019
SUBJECT: GRB191016A: MITSuME Okayama optical observation
DATE:    19/10/17 11:15:15 GMT
FROM:    Sayaka Toma at Tokyo Institute of Technology  <toma at hp.phys.titech.ac.jp>

S. Toma, M. Niwano, R. Adachi, K. L. Murata,  M. Oeda, K.Shiraishi, K. Iida,
F. Ogawa, R. Hosokawa, Y. Yatsu, and N. Kawai (TokyoTech)
report on behalf of the MITSuME collaboration:


We searched for the optical counterpart of GRB 191016A (J.D. Gropp et
al., GCN Circular #26008) with the optical three color (g', Rc, and
Ic) CCD cameras
attached to the MITSuME 50 cm telescope of Okayama
Astrophysical Observatory, Okayama, Japan.

The observation started on 09:37:49.50 UT which corresponds to
5.5 hours after the trigger.
We detected the point source at the position consistent with the
afterglow detected previously (Alan M. Watson et al. GCN #26010).
The measured magnitudes and 3-sigma limit are listed as follows.

T0+[sec]    MID-UT      T-EXP[sec]        g'       Rc        Ic
———————————————————————————————————————————————————
20794      13:31:46          20040              19.5+/-0.4
> 19.0     18.6+/-0.2
-------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 and UCAC4 catalog for flux calibration.
The magnitudes are expressed in the Vega system.