TITLE: GCN CIRCULAR NUMBER: 11660 SUBJECT: GRB 110207A: MASTER prompt and early optical observations DATE: 11/02/07 13:52:28 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres, S.Yazev, N.M.Budnev, Irkutsk State University E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, V.Shumkov, S.Shurpakov Sternberg Astronomical Institute, Moscow State University V.Krushinski, I.Zalozhnich, A. Popov Ural State University, Kourovka A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory Two MASTER II robotic telescopes (MASTER-Net: http://observ.pereplet.ru) located in Amur-Blagoveschensk and Tunka-Baykal was pointed to the GRB110207A 65 and 30 sec after GRB time correspondingly. On our first (10s exposure) set we haven`t found optical transient within SWIFT-BAT error-box (Littlejohns et al., GCN Curc 11658). Because GRB duration is 40 sec, the first images from Tunka is prompt. The obdervations was done at high zenith distance (>80 degrees). The 3-sigma upper limit has been about: ----------------------------------------------------------------------- Start Time mean time Exp Limit Filter Site after trigger after trigger (s) ----------------------------------------------------------------------- 30s 35s 10 13.0 V+P\/ Tunka-Baykal 65s 70s 10 14.1 V+P-| Amur-Blagoveschensk 65s 747s 1370 17.0 V+P-| Amur-Blagoveschensk 1700s 1790s 180 17.4 R Tunka-Baykal ------------------------------------------------------------------------ P - is polarization. The message may be cited. mailto: lipunov@sai.msu.ru