//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28007 SUBJECT: IceCube-200620A: MASTER previous detection of ZTF20abgvabi/AT2020ncr DATE: 20/06/21 22:59:26 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E.Gorbovskoy, N.Tiurina, K.Zhirkov, P.Balanutsa,A.Kuznetsov,F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics Department), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix Aguilar OAFA), H. Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias), D. Buckley(South African Astronomical Observatory), O.A. Gres, N.M. Budnev (Irkutsk State University, API), A. Gabovich, Yu. Sergienko, V.Yurkov (Blagoveschensk Educational State University) MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) started IceCube-200620A inspection (The IceCube Collaboration GCN 27997) 8560 sec after trigger time at 2020-06-20 16:32:52 UT (Lipunov et al. GCN 28001, see cover map and error-box altitude at alert time and inspect time at https://master.sai.msu.ru/site/master2/observ.php?id=1386385 ) ZTF candidate ZTF20abgvabi/AT 2020ncr with RA,Dec(2000)=162.5306820 +12.1462203 (Reusch et al. GCN 28005) presents at MASTER archive images on 2015-12-25 (60s exposition). MASTER database (2006-2020) analysis will be continued.