TITLE: GCN CIRCULAR NUMBER: 18616 SUBJECT: GRB 151027A: SAO RAS and Mt. Terskol observations DATE: 15/11/18 12:41:05 GMT FROM: Moskvitin Alexander at SAO RAS A. S. Moskvitin (SAO RAS), I. V. Sokolov (Terskol Branch of INASAN) report on behalf of larger GRB follow-up team. We observed the field of GRB 151027A twice: with 2-m Zeiss-2000 + FLI CCD (Mt. Terskol) and 1-m Zeiss-1000 + EEV 42-40 CCD (SAO RAS) on November 6 and 12 respectively (T-T0 = 10.5 and 16.5 days). We have obtained 10x300 and 24x300 sec. frames in R band. We do not detect the GRB OT (Maselli et al., GCNC #18478) down to the limiting magnitude R_lim = 22.8 in both stacked images. As the standard stars we used USNO-B1 objects from GCNCs #18521, 18558 and 18559. We should note that nearby USNO-B1 source reported by S. Dichiara et al. (GCNC #18510) and E. Mazaeva et al. (GCNC #18559) is clearly detected in our images.