TITLE: GCN CIRCULAR NUMBER: 23415 SUBJECT: GRB 181110A: MITSuME Akeno optical observation DATE: 18/11/10 12:11:22 GMT FROM: Katsuhiro L. Murata at Nagoya U K. L. Murata, R. Itoh, Y. Tachibana, S. Harita, K. Morita, K. Shiraishi, K. Iida, M. Oeda, M. Niwano, R. Adachi, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration We searched for the optical counterpart of GRB 181110A (Evans et al., GCN Circular #23413) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of AkenoObservatory, Yamanashi, Japan. The observation for the position of the 1st GCN of this trigger (trigger #871316) started on 08:44:56 UT which corresponds to 85 sec after the trigger. Here we report the result of the images after 08:55:15 UT. We detected the point source at the position consistent with the Swift/UVOT observation (Evans et al., GCN Circular #23413) and the Kanata observation (Yamanaka et al., GCN Circular # 23414). The measured magnitudes are listed as follows. T0+[min] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------------------------------------------------- ~12 09:00:58.3 420 ~14 ~14 ~14 ------------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used GSC2.3 catalog for flux calibration. The magnitudes are expressed in the AB system. Further analysis is ongoing.