TITLE: GCN CIRCULAR NUMBER: 17362 SUBJECT: GRB 150123A: MASTER inspection DATE: 15/01/30 10:24:03 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, N.Tyurina, P.Balanutsa, D.Denisenko, A.Kuznetsov, V.Kornilov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute O.Gres, K.Ivanov, S.Yazev, N.M.Budnev, V.A.Poleshchuk Irkutsk State University V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University 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, Kourovka D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory H. Levato and C. Saffe Instituto de Ciencias Astronomicas de la Tierra y del Espacio (ICATE), San Juan, Argentina C. Mallamacci, C. Lopez and F. Podest Observatorio Astronomico Felix Aguilar (OAFA), San Juan National University, Argentina MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka, Kislovodsk and SAAO made inspection inside MAXI GRB150123A (Fukushima et. al GCN 17345) error box which starting 3297 sec after trigger time at 2015-01-23 15:56:47 UT. We don't find creadible OT candidate in MAXI error box on single and coadd images with following upper limits. T_start T-Tmid Exp Site Coadd Mlimit Comment 15:56:47 3297 180 Tunka -- 15.0 High clouds 15:56:55 3305 180 Kilov -- 17.0 5 images only 16:28:50 6562 1800 Tunka 10 19.0 17:14:03 8974 1800 Tunka 10 19.0 18:44:04 13186 180 SAAO -- 18.5 Starting after sunset. 18:44:04 14398 1620 SAAO 9 20.6 19:20:41 17075 1800 SAAO 10 20.6 We also check all Swift-XRT transints (Melandri et. al. GCN 17348) on all out images. Source #1 is a galaxy with no avidance for brightening. Source #2 empty space with no OT and known stars at edge of error circle Source #3 position is blended by close bright stars. This message may be cited.