GCN Circular 22140
Subject
GRB 171120A: MITSuME Akeno optical upper limits
Date
2017-11-21T10:18:12Z (6 years ago)
From
Katsuhiro L. Murata at Nagoya U <murata@u.phys.nagoya-u.ac.jp>
H. Mamiya, R. Itoh, K. L. Murata, T. Yoshii, Y. Tachibana, S. Harita, K.
Morita, T. Ozawa, K. Shiraishi, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 171120A (A. Tohuvavohu et
al., GCN Circular #22133) with the optical three color (g', Rc, and Ic) CCD
cameras attached to the MITSuME 50 cm telescope of Akeno Observatory,
Yamanashi, Japan.
The observation started on 2017-11-20 15:38:32.17 UT. We did not find any
new point source within enhanced XRT circle (P.A. Evans al., GCN Circular
#22135) in all three bands.
We obtained following limits for the magnitudes.
T0+[hour] MID-UT T-EXP[sec] g' Rc Ic
------------------------------------------------------------------------------------------------------
~3.26 18:40:07.63 9960 >21.5 >20.7 >19.8
------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.