TITLE: GCN CIRCULAR NUMBER: 28819 SUBJECT: Swift GRB 201031A: Global MASTER-Net observations report DATE: 20/11/01 00:18:23 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (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, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (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 GRB 201031A ( S. Laha et al., GCN 28814) errorbox 34924 sec after notice time and 35035 sec after trigger time at 2020-11-01 00:03:50 UT, with upper limit up to 16.6 mag. Observations started at twilight. The observations began at zenith distance = 76 deg. The sun altitude is -13.9 deg. The galactic latitude b = 20 deg., longitude l = 11 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1472957 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 35125 | MASTER-OAFA | C | 180 | 16.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.