TITLE: GCN CIRCULAR NUMBER: 18825 SUBJECT: GRB 160104A: MITSuME Okayama upper limits DATE: 16/01/05 00:07:57 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of MITSuME and OISTER collaboration: We observed the field of GRB 160104A (Melandri et al., GCNC 18815) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory. The observation started on 2016-01-04 12:42:48 UT (~1.3 h after the burst). We could not detect the previously reported afterglow (Guidorzi et al., GCNC 18816; Saito et al., GCNC 18817) in all the three bands. Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration. #T0+[day] MID-UT T-EXP[sec] g' Rc Ic ----------------------------------------------------- 0.08648 13:28:43 4620.0 >20.4 >20.0 >19.4 ----------------------------------------------------- T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec]