TITLE: GCN CIRCULAR NUMBER: 11924 SUBJECT: GRB 110411A: MASTER prompt and follow-up optical limits DATE: 11/04/12 11:00:43 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs O. Gres, K.Ivanov, V.A.Poleshchuk, S.Yazev, N.M.Budnev, O.Chuvalaev Irkutsk State University E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka(Siberia) was pointed to the GRB110411A (Grupe et al., GCN 11918) 19 sec s after notice time and 44 sec after GRB time at 2011-04-11 19:34:55.3 UT in two polarizations. A series of Polarization, White and R-band images were obtained. We have not found OT at Xinglong TNT OT candidate position (Xin et al., GCN Circ 11923). The results from two tubes are: (GRB Time = 2011-04-11 19:34:11 UT) Date time Exp.time Limit Filt.(W-white) UT (s) (5-sigma) 2011-04-11 19:34:55 10 17.4 W 2011-04-11 19:34:55 10 18.0 W 2011-04-11 19:35:23 10 14.8 P/ 2011-04-11 19:35:23 10 15.4 P\ 2011-04-11 19:35:50 20 15.5 P/ 2011-04-11 19:35:51 20 16.0 P\ 2011-04-11 19:36:29 30 16.0 P/ 2011-04-11 19:36:29 30 16.5 P\ 2011-04-11 19:37:17 40 16.0 P/ 2011-04-11 19:37:18 40 16.7 P/ 2011-04-11 19:38:14 50 16.3 P\ 2011-04-11 19:38:14 50 16.9 P/ 2011-04-11 19:39:22 60 16.5 P\ 2011-04-11 19:39:22 60 17.0 P/ 2011-04-11 19:40:39 80 16.6 P\ 2011-04-11 19:40:39 80 17.2 P/ 2011-04-11 19:42:14 3790 19.4 P\ 2011-04-11 19:42:14 100 17.0 P/ 2011-04-11 19:42:15 3970 18.9 P\ 2011-04-11 19:42:15 100 17.7 P/ 2011-04-11 19:44:10 120 17.4 P\ 2011-04-11 19:44:11 120 17.4 P/ 2011-04-11 19:46:26 150 17.8 P\ 2011-04-11 19:46:26 150 17.7 P/ 2011-04-11 19:49:11 180 18.1 P\ 2011-04-11 19:49:12 180 17.9 P/ 2011-04-11 19:52:30 180 18.0 P\ 2011-04-11 19:52:30 180 17.9 P/ 2011-04-11 19:55:46 180 18.1 P\ 2011-04-11 19:55:46 180 18.0 P/ 2011-04-11 19:59:02 180 18.1 P\ 2011-04-11 19:59:02 180 18.1 P/ 2011-04-11 20:02:17 180 18.1 P\ 2011-04-11 20:02:18 180 18.1 P/ 2011-04-11 20:05:33 180 18.1 P\ 2011-04-11 20:05:34 180 18.1 P/ 2011-04-11 20:08:49 180 18.0 P\ 2011-04-11 20:08:49 180 18.0 P/ 2011-04-11 20:12:06 180 18.0 P\ 2011-04-11 20:12:06 180 18.0 P/ 2011-04-11 20:15:23 180 18.1 P\ 2011-04-11 20:15:24 180 18.0 P/ 2011-04-11 20:18:40 180 18.1 P\ 2011-04-11 20:18:41 180 18.0 P/ 2011-04-11 20:21:57 180 18.1 P\ 2011-04-11 20:21:58 180 18.0 P/ 2011-04-11 20:25:14 180 18.0 P\ 2011-04-11 20:25:14 180 18.0 P/ 2011-04-11 20:28:38 180 18.1 P\ 2011-04-11 20:28:40 180 18.0 P/ 2011-04-11 20:31:56 180 18.1 P\ 2011-04-11 20:31:57 180 18.0 P/ 2011-04-11 20:35:13 180 18.0 P\ 2011-04-11 20:35:13 180 17.9 P/ 2011-04-11 20:38:32 180 18.1 P\ 2011-04-11 20:38:32 180 17.9 P/ 2011-04-11 20:41:48 180 17.8 P\ 2011-04-11 20:41:48 180 17.9 P/ 2011-04-11 20:45:04 180 17.8 P\ 2011-04-11 20:45:04 180 17.9 P/ 2011-04-11 20:48:20 180 17.8 P\ 2011-04-11 20:48:20 180 17.7 P/ 2011-04-11 20:51:45 180 17.7 P\ 2011-04-11 20:51:46 180 17.7 P/ 2011-04-11 20:59:09 180 19.0 W 2011-04-11 20:59:09 900 19.4 W 2011-04-11 20:59:09 180 18.8 R 2011-04-11 20:59:09 900 19.2 R 2011-04-11 21:02:42 180 18.7 W 2011-04-11 21:02:43 180 18.8 R 2011-04-11 21:06:52 180 18.5 W 2011-04-11 21:06:52 180 18.5 R 2011-04-11 21:10:28 180 18.2 W 2011-04-11 21:10:28 180 18.3 R 2011-04-11 21:14:04 180 18.0 W 2011-04-11 21:14:04 180 18.0 R The message may be cited.