TITLE: GCN CIRCULAR NUMBER: 11228 SUBJECT: GRB 100906A: MASTER early OT observations DATE: 10/09/06 14:12:54 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs 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 Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka Two MASTER robotic telescopes (MASTER-Net: http://observ.pereplet.ru) located near Baykal Lake (Tunka) and Blagoveschensk was pointed to the Swift GRB 100906A (Markwardt et al., GCN CIRCULAR 11227) 23 sec after Notice time (38 s after trigger time) and 43 s after Notice time (58s after trigger time). We have a number polarization, unfiltered images with exposition 10, 20, 30, 40, 60... s. We see bright OT at Swift Uvot position (Markwardt et al., GCN CIRCULAR 11227). The message may be cited. mailto: lipunov@sai.msu.ru