TITLE: GCN CIRCULAR NUMBER: 23249 SUBJECT: GRB 180914B : continued TSHAO optical observations DATE: 18/09/17 20:04:01 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Pozanenko (IKI), I. Reva (FAPHI), A. Kusakin (FAPHI), A. Volnova (IKI), M. Krugov (FAPHI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 180914B (Ursi, et al., GCN 23226; Bissaldi et al., GCN 23232; Frederiks et al., GCN 23240) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on September 17 (UT) 14:28:30. We observed the object reported e.g. (Zheng & Filippenko GCN 23237; Troja et al. GCN 23238; de Ugarte Postigo et al., GCN 23239; Paul & Kuin, GCN 23241). Preliminary photometry of the object is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2018-09-17 14:28:30 2.87843 R 60*60 20.53 0.07 22.2 The photometry is based on several nearby SDSS-DR9 stars SDSS-DR9_id R(Lupton) J220926.80+250130.1 15.705 J220922.87+250206.0 16.156 J220929.88+250257.7 15.812 J220928.05+250309.0 17.230 J220928.90+250327.6 15.524 J220924.12+250415.7 15.485 J220920.37+250610.6 15.050 J220902.04+250312.5 15.321