TITLE: GCN CIRCULAR NUMBER: 29471 SUBJECT: Swift GRB210211.36: Global MASTER-Net observations report DATE: 21/02/11 08:54:08 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 GRB210211.36 (trigger No 1032024,17h 57m 43.92s , -46d 17m 56.4s, R=0.05) errorbox 25 sec after notice time and 43 sec after trigger time at 2021-02-11 08:44:02 UT, with upper limit up to 15.3 mag. The observations began at zenith distance = 52 deg. The sun altitude is -17.9 deg. The galactic latitude b = -11 deg., longitude l = 346 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1544962 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 49 | MASTER-OAFA | C | 10 | 15.3 | 79 | MASTER-OAFA | C | 10 | 15.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.