TITLE: GCN CIRCULAR NUMBER: 15534 SUBJECT: GRB 131127B: MASTER-Net optical observations DATE: 13/11/28 15:22:44 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, D.Denisenko, Sternberg Astronomical Institute, Moscow 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.Krushinsky, I.Zalozhnih, A. Popov Ural Federal University, Yekaterinburg, 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 GRB131127.59 73 sec after GRB time at 2013-11-27 14:13:31.093 UT. Fortunately, the central part (42%) of the IPN error box (Golenetskii et al., GCN 15529) was covered by first MASTER image (10s exposure). Unfortunatelly, observations was done at the very high zenit distance (~85 degrees). We haven`t found optical transient. The 5-sigma upper limit has been about 14.1 mag We have 4 images (the one of the tube was under horizont): Id (image) Coord Pro.type time Exp.time Limit 587443 20h 19m 27.4s -02d 51m 25s Alert 14:13:31 10 14.1 587444 20h 19m 27.3s -02d 51m 31s Alert 14:14:29 30 15.0 587446 20h 19m 27.0s -02d 51m 41s Alert 14:15:52 40 14.8 587448 20h 19m 27.1s -02d 51m 42s Alert 14:17:38 60 15.0 The fist image (FOW = 2x2 degrees) with IPN error box is available at http://master.sai.msu.ru/static/GRB/grb131127_IPN.jpeg . The reduction is continued. The message may be cited.