TITLE: GCN CIRCULAR NUMBER: 11126 SUBJECT: GRB100816A: MITSuME optical upper limits DATE: 10/08/18 06:09:10 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 the MITSuME collaboration: We observed the field of GRB 100816A (Oates et al., GCN 11102) 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 2010-08-16 14:00:49 UT (~13.4 h after the burst). We did not find any new point source within the enhanced XRT error circle (Evans et al., GCNC 11110) in all the three bands. We could not detect the previously reported host galaxy (Im et al., GCN 11108; Tanvir et al., GCN 11109; Malesani et al., GCN 11120). Three sigma upper limits of the OT are listed below. We used GSC 2.3 catalog for flux calibration. T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.67447 16:49:05 6240.0 >21.0 >20.5 >19.9 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec]