TITLE: GCN CIRCULAR NUMBER: 17564 SUBJECT: GRB 150309A: ISON-Kislovodsk optic upper limit DATE: 15/03/11 12:35:27 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Vazaeva (IKI), V. Nevskiy (ISON), A. Volnova (IKI), I. Molotov (KIAM), A. Pozanenko (IKI),report on behalf of larger collaboration: We observed the field of the Swift GRB 150309A (Cummings et al., GCN 17553) with Santel-400AN telescope of ISON-Kislovodsk observatory starting on Mar. 09 (UT) 23:11:26, i.e. ~8.5 min after the burst trigger. In the enhanced XRT position (Osborne et al., GCN 17555) we do not detect any object. An upper limit is following Date UT start t-T0 Filter Exp. UL(3 sigma) (mid, days) (s) 2014-09-03 23:11:26 0.02590 None 49*60 20.0 The photometry is based on USNO-B1.0 star USNO-B1.0_id R2 1764-0030460 15.42