TITLE: GCN CIRCULAR NUMBER: 15948 SUBJECT: GRB 140311B: MASTER early optical observations DATE: 14/03/11 22:02:51 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, M. Pruzhinskaya, D.Denisenko, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka was pointed to the GRB140311B 29 sec after notice time and 107 sec after trigger time at 2014-03-11 21:16:16 UT in two polarizations. On our first (20s exposure) set we haven`t found optical transient within SWIFT error-box (Racusin et. al. GCN 15945). The 5-sigma upper limit has been about 17.0 mag. The observations is proceed. MASTER II robotic telescope located in Blagoveschensk was pointed to the GRB140311B 9 sec after notice time and 85 sec after trigger time at 2014-03-11 21:15:54 UT in two polarizations. On our first (20s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 14.0 mag. The observations on this place made on the bright morning sky. The message may be cited. [GCN OPS NOTE(12mar14): Per author's request, the Subject was changed from "MASTER OT light curve (fwd)" to "MASTER early optical observations".]