TITLE: GCN CIRCULAR NUMBER: 7305 SUBJECT: GRB080212: Optical afterglow candidate observed by MITSuME Telescope DATE: 08/02/13 11:50:53 GMT FROM: Michitoshi Yoshida at Okayama Astrophysical Obs M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We performed optical imaging observation (g', Rc, and Ic) of the field of GRB 080212 (Ziaeepour et al. GCN 7296) with 50cm MITSuME telescope at Okayama Astrophysical Observatory from UT 17:36:37 (124 sec after the trigger) to UT 20:30:38 on Feb 12 2008. We found a 18 mag star in the vicinity of the XRT position (Goad et al. GCN 7300). This is the late-K star reported by Berger (GCN 7304). Although we could not spatially resolve the faint source close to this star reported by Berger (GCN7304), we found that a fading component is overlaid on the star. This component is a GRB afterglow candidate. We estimated the magnitudes of the fading component by subtracting the flux of the star at 2 hours after the trigger from the star magnitude at early time. The estimated magnitudes of the fading component are summarized below. Observation date 2008-02-12 UT mid-UT exp-T g' Rc Ic --------------------------------------------------------- 17:42:47 10min 19.46+-0.26 17.77+-0.15 17.98+-0.22 18:00:27 22min > 21.0 18.77+-0.14 18.91+-0.21 18:19:08 52min > 21.0 19.88+-0.10 > 20.5 18:58:37 113min > 21.0 > 20.5 > 20.5 ---------------------------------------------------------