TITLE: GCN CIRCULAR NUMBER: 15171 SUBJECT: GRB 130903A: ISON-Kislovodsk optical Upper Limits DATE: 13/09/03 13:21:41 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), V. Nevskiy (ISON), I. Molotov (KIAM), A. Pozanenko (IKI), report on behalf of larger collaboration: We observed the field of GRB 130903A (INTEGRAL trigger 6930; Mereghetti et al. 2013, GCN 15169) with SANTEL-400AN (0.4-m f/3) telescope of ISON-Kislovodsk observatory.Observations started on Sep. 09 (UT) 01:11:40, i.e. 34 minutes after burst triger. We obtained several unfiltered images of 100 s exposure. We do not detect any source within 1.5 arcmin of error circle localization (Mereghetti et al. 2013, GCN 15169) . Photometry of combined image is following T_start, T0+, Exp., Filter, UL (3 sigma) (UT) mid (d) (s) 01:11:40T01:11:40 0.02363 1000 none >19.6 and based on SDSS stars, R (gri -> R transformations by Lupton 2005): # SDSS R Err_R 1 J052835.34-000624.7 15.543 0.013 2 J052817.12-000749.0 14.650 0.012 3 J052841.64-000642.3 14.233 0.013 Within error circle (Mereghetti et al. 2013, GCN 15169) we note a presence of probable bright galaxy J052830.20-000723.9 r=19.706 (however marked in SDSS-DR9 as point like object).