[vsnet-grb-info 9722] GRB 100901A: Kanata Telescope observation of the optical afterglow

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11190
SUBJECT: GRB 100901A: Kanata Telescope observation of the optical afterglow
DATE:    10/09/03 06:03:58 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida at oao.nao.ac.jp>

M. Yoshida, M. Sasada, T. Komatsu and K. S. Kawabata (HASC, Hiroshima
University)

We performed R band imaging observation of the optical afterglow of
GRB 100901A (Immler et al., GCN 11159) with the 1.5m Kanata telescope
of Hiroshima University.

The observation was made from 2010-09-02 15:07:24 UT (~1.06 day after
the burst) to 15:50:33 UT.  The previously reported afterglow (e.g
Immler et al. GCN 11159; Kuroda et al. GCN 11172; or Kann et al.
GCN 11187) was clearly detected. The afterglow showed a marginal
increasing trend in brightness within this observation.

Photometric results of the afterglow are listed below. We used USNO-
B1.0 1127-0027231 (R = 15.37) for flux calibration.

#T0+[day]  MID-UT    T-EXP[sec]     Rc    err
-----------------------------------------------
1.070266   15:15:21   900.0       18.62   0.10
1.081620   15:31:42   900.0       18.60   0.07
1.096759   15:53:30   900.0       18.54   0.04
-----------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]