TITLE: GCN CIRCULAR NUMBER: 11216 SUBJECT: GRB 100905A: MASTER Prompt Optical Observations DATE: 10/09/05 17:43:04 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 V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka 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 MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located at Tunka was pointed to the Swift GRB 100905A (Marshall et al. GCN Circ. 11214) 33 sec after Notice time (55 s after GRB trigger time) in two polarizations bands. There is no optical transient at XRT position (Marshall et al. GCN Circ. 11214). Following data has been received: start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd? Band -------------------------------------------------------------------------- 15:09:10 15:09:20 10 16.5 55.0 N Polariz 15:09:39 19:09:59 20 17.1 84.0 N Polariz 15:10:45 15:11:15 30 17.3 150.0 N Polariz 15:11:35 15:12:15 40 17.5 200.0 N Polariz -------------------------------------------------------------------------- The observations and data reductions is continued. The message may be cited.