TITLE: GCN CIRCULAR NUMBER: 29056 SUBJECT: GRB 201214B: MITSuME Akeno optical upper limits DATE: 20/12/16 13:52:03 GMT FROM: Noriatsu Nakamura at Tokyo Inst. of Tech. N. Nakamura, R. Hosokawa, K. L. Murata, R. Adachi, M. Niwano, F. Ogawa, N. Ito, S. Ogata, H. Takamatsu, H. Hara, Y. Yatsu, and N. Kawai (TokyoTech) report on behalf of the MITSuME collaboration: We observed the field of GRB 201214B (The Fermi GBM team, GCN #29039, P. Evans et al., GCN #29043, V. Lipunov et al., GCN #29044, D. Palmer et al., GCN #29045, B. Sbarufatti et al., GCN #29052 ) 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 with a series of 60 sec exposures started at 2020-12-15 18:51:41 UT(28.8 hour after trigger). We did not find any new point sources within the enhanced Swift BAT circle (D. Palmer et al., GCN #29045) in all three bands. We obtained the 5-sigma limits of the stacked images as follows T0+[hour] MID-UT T-EXP[sec] 5-sigma limits ------------------------------------------------------------------------------------------------ 28.8 18:51:41 10380 g'>20.9,Rc>21.0,Ic>20.3 ------------------------------------------------------------------------------------------------ T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used the PS1 catalog for flux calibration. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al., https://doi.org/10.1093/pasj/psaa091, https://arxiv.org/abs/2008.11486; https://github.com/MNiwano/Eclaire).