TITLE: GCN CIRCULAR NUMBER: 28271 SUBJECT: GRB 200819A: MITSuME Ishigaki optical upper limits DATE: 20/08/20 04:43:13 GMT FROM: Katsuhiro L. Murata at Nagoya U Takashi Horiuchi, Hidekazu Hanayama (NAOJ), Katsuhiro L. Murata, Yoichi Yatsu, Nobuyuki Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 200819A (Dichiara et al., GCN 28263; Evans et al., GCN 28265) with the optical three color (g', Rc, and Ic) CCD cameras attached to the 105 cm Murikabushi telescope of Ishigakijima Astronomical Observatory, Okinawa, Japan. The observation with a series of 60 sec exposures started on 2020-08−19 16:35:33 UT. Throughout, the images were terribly extended by the altitude oscillation of the Murikabushi Telescope. We stacked the 79 images and did not find any new point sources other than the USNO-B1.0 sources from the stacked images. We obtained the SN = 10 limits as follows. T0+[min] MID-UT T-EXP[sec] SN=10 limits ------------------------------------------------------------------------------------------------ 52 2020-08-19T17:21:38 960 g'>18.7, Rc>19.0, Ic>17.8 ------------------------------------------------------------------------------------------------