TITLE: GCN CIRCULAR NUMBER: 12617 SUBJECT: GRB 110921A: optical observations in Maidanak observatory DATE: 11/12/04 20:50:27 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (SAI MSU), M. Ibrahimov (UBAI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We update results of Maidanak observations preliminary reported in GCN 12380. We observed the field of the Swift GRB 110921A (Baumgartner et al., GCN 12373) with AZT-22 telescope of Maidanak observatory starting Sep. 21 (UT) 17:45:30. Several images in R-filter of 300 s exposure were taken under moderate seeing (FWHM ~ 1.7"). We detect a source in coordinates (J2000) 19 36 23.363 +36 19 43.02 with uncertainty of 0.2" and brightness of R = 22.0 +/- 0.15. This source is rather consistent both in position and brightness, with the SDSS object (Xu et al. GCN 12385; Vreeswijk et al. GCN 12387). So we do not detect afterglow reported by (Xu et al. GCN 12385; Breeveld et al. GCN 12389; Tokoyoda et al. GCN 12410; Volnova et al. GCN 12438). Tstart UT, T0+, Filter, Exposure, OT, Upper Limit (3 sigma) (mid, d) (s) 17:45:30 0.17895 R 8*300 n/d 22.5