GCN Circular 17091

D. Kuroda (OAO, NAOJ),  H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ),
K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima),
K. Ohta (Kyoto) and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME and OISTER collaboration:

We observed the field of GRB 141121A (Lien et al., GCNC 17075)
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 2014-11-23 17:42:18 UT (~2.6 days after the burst).
We detected the previously reported afterglow (Tanga et al., GCNC 17078;
Perley et al., GCNC 17081) in all the three bands.

Photometric results of the OT are listed below.
We used SDSS-DR7 catalog for flux calibration.

#T0+[day]  MID-UT    T-EXP[sec]  g'    g'_err  Rc    Rc_err  Ic    Ic_err
--------------------------------------------------------------------------
2.61049    18:29:49    4800.0    21.02 0.08    20.44 0.07    19.64 0.09
--------------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]