TITLE: GCN CIRCULAR NUMBER: 32230 SUBJECT: Swift GRB220620.02: Global MASTER-Net observations report DATE: 22/06/20 04:28:33 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), 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), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB220620.02 (trigger No 1111002,19h 57m 34.27s , +35d 00m 06.1s, R=0.05) errorbox 11636 sec after notice time and 12108 sec after trigger time at 2022-06-20 03:45:59 UT, with upper limit up to 15.6 mag. The observations began at zenith distance = 78 deg. The sun altitude is -76.5 deg. The galactic latitude b = 3 deg., longitude l = 71 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2010790 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 12199 | MASTER-OAFA | C | 180 | 14.9 | 14128 | MASTER-OAFA | C | 180 | 15.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.