TITLE: GCN CIRCULAR NUMBER: 28125 SUBJECT: Swift GRB200716C: Global MASTER-Net OT detection DATE: 20/07/16 23:41:37 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, F. Balakin, I. Gorbunov Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk Irkutsk State University A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk D. Buckley, S. Potter, A. Kniazev, M. Kotze South African Astronomical Observatory R. Podesta, Carlos Lopez and F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) Hugo Levato Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) MASTER-IAC robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) was pointed to the GRB200716C (Ukwatta et al, GCN 28124) 55 sec after notice time and 79 sec after trigger time at 2020-07-16 22:59:00 UT. On our 5-th (50s exposure) set , obtained 243 sec after tigger time at 2020-07-16 23:01:45 UT, we found an optical transient within Swift error-box (ra=196.012 dec=29.6292 r=0.05) brighter. T-Tmid Date Time Expt. Ra Dec Mag ---------|---------------------|-------|-----------------|-----------------|----- 268 2020-07-16 23:01:45 50 (13h 04m 02.41s , +29d 38m 39.4s) 16.3 The 5-sigma upper limit has been about 16.6mag The message may be cited.