TITLE: GCN CIRCULAR NUMBER: 28633 SUBJECT: Swift GRB201015.95: Global MASTER-Net OT detection DATE: 20/10/15 23:00:44 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk Irkutsk State University V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk R. Podesta, Carlos Lopez and F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias D. Buckley, S. Potter, A. Kniazev, M. Kotze South African Astronomical Observatory MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the GRB201015.95 67 sec after notice time and 88 sec after trigger time at 2020-10-15 22:51:41 UT. On our 3-th (30s exposure) set , obtained 168 sec after tigger time at 2020-10-15 22:53:01 UT, we found 1 optical transient within Swift error-box (ra=354.342 dec=53.3925 r=0.05) brighter than 17.6. T-Tmid Date Time Expt. Ra Dec Mag ---------|---------------------|-------|-----------------|-----------------|------- 183 2020-10-15 22:53:01 30 (23h 37m 16.42s , +53d 24m 55.8s) 16.9 The 5-sigma upper limit has been about 17.6mag The message may be cited.