[vsnet-grb-info 20572] GRB 180418A: MITSuME Ishigakijima Optical Observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22670
SUBJECT: GRB 180418A: MITSuME Ishigakijima Optical Observation
DATE:    18/04/24 02:00:28 GMT
FROM:    Ryosuke Itoh at Tokyo Institute of Tech.  <itoh at hp.phys.titech.ac.jp>

T. Horiuchi,  H. Hanayama, M. Honma (IAO, NAOJ),
R. Itoh, K. Shiraishi, K. Murata, Y. Tachibana and  N. Kawai (Tokyo Tech)
report on behalf of the MITSuME and OISTER collaboration:

We observed the field of GRB 180418A (D'Elia et al.,GCN 22646)
with the optical three color (g', Rc and Ic) CCD camera attached
to the Murikabushi 1m telescope of Ishigakijima Astronomical
Observatory.

The observation started on 2018-04-18 13:55:32 UT, (~7 hours after
the burst). We detected the previously reported afterglow
(W. Zheng and A. Filippenko, GCNC22647) in the R band.

The photometric results of the OT are listed below.
We used UCAC-4 catalog for flux calibration.

#T0+[hour]  MID-UT    T-EXP[sec] g'   Rc   Ic
-------------------------------------------------------------------
8.6    15:22:01      10380  >22.8  22.4+/-0.5 >22.0
-------------------------------------------------------------------
T0+ : Elapsed time after the burst [hour]
T-EXP: Total Exposure time [sec]