TITLE: GCN CIRCULAR NUMBER: 16501 SUBJECT: GRB 140629A: MITSuME Akeno Optical observation DATE: 14/07/02 06:24:29 GMT FROM: Taketoshi Yoshii at Tokyo Tech Y. Yano, T. Yoshii, Y. Saito, Y. Tachibana, H. Ohuchi, S. Kurita, Y. Ono, T. Fujiwara, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 140629A (A. Y. Lien et al., GCN Circular #16477) 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 2014-06-29 14:23:32 UT (6 min after the burst). We detected the previously reported optical afterglow of GRB140629A (V.Yurkov et al., GCN Circular #16478) in the g', Rc and Ic band. The measured magnitudes are listed below. T0+[sec] MID-UT T-EXP[sec] g' Rc Ic ---------------------------------------------------------------------------------------------------- 362 14:24:02 60.0 15.06+/-0.04 14.25+/-0.03 13.83+/-0.03 11482 17:43:45 600.0 18.77+/-0.23 18.06+/-0.16 17.67+/-0.21 ---------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used GSC2.3 catalog for flux calibration.