TITLE: GCN CIRCULAR NUMBER: 19623 SUBJECT: GRB 160629A: SAO RAS independent OT detection DATE: 16/06/30 03:55:14 GMT FROM: Moskvitin Alexander at SAO RAS V. Sokolov, A. Valeev, A. Moskvitin and V. Komarova (SAO RAS) report on behalf of a larger team. We observed the error box of INTEGRAL GRB 160629A (Gotz et al. GCNC #19621) with the SAO RAS 6-meter telescope BTA + Scorpio. The observations started since ~10 minutes after the trigger. Several images in Rc band were obtained. We find a fading source with the coordinates R.A. = 00:19:27.1 Dec. = +76:58:00.7 error = 0".5 This object is consistent with the OT reported by Klotz et al. (GCNC #19622). We used USNO-B1 star 1669-0002297 (R.A = 00:19:31.12; Dec. = +76:57:41.3) with R2 = 15.53 for the calibrations. Preliminary magnitudes of OT are as following. T-T0,s exp,s R_mag err ========================== 615 30 17.40 0.03 688 60 17.55 0.03 848 180 17.71 0.02 1039 60 17.85 0.05 1118 30 18.13 0.08 1393 80 18.21 0.09 1508 80 18.24 0.11 1648 80 18.41 0.10 1964 180 18.55 0.09 3859 180 19.25 0.07 4066 180 19.18 0.04 4262 180 19.25 0.04 4483 180 19.29 0.11 4725 180 19.24 0.05 4926 180 19.24 0.03 5132 180 19.33 0.04 5347 180 19.30 0.04 5585 180 19.43 0.05 5824 180 19.44 0.06 ftp://ftp.sao.ru/pub/grb/GRB160629A/GRB160629A_BTA.jpg