TITLE: GCN CIRCULAR NUMBER: 18316 SUBJECT: GRB 150915A: MASTER-NET optical observations DATE: 15/09/15 22:38:43 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov, D.Kuvshinov, E.Popova Lomonosov Moscow State University, Sternberg Astronomical Institute K.Ivanov, O.Gres, N.M.Budnev, S.Yazev, Irkutsk State University D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A.Gabovich Blagoveschensk Educational State University, Blagoveschensk V.Krushinski, I.Zalozhnih 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 IAC (Tenerife, Spain) was pointed to the GRB150915A 22 sec after notice time and 95 sec after trigger time at 2015-09-15 21:20:03 UT in two polarizations. On our first single (20s exposure) and coadd (760s exposure) sets we haven`t found optical transient within SWIFT error-box (Elia et al. GCN 18315). The 5-sigma upper limit has been about 17.3 on single and 19.8 on coadd image. MASTER II robotic telescope located in SAAO (South Africa) was pointed to the GRB150915A 25 sec after notice time and 100 sec after trigger time at 2015-09-15 21:20:07 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 17.2 mag The message may be cited.