TITLE: GCN CIRCULAR NUMBER: 31190 SUBJECT: IceCube Alert 211208.84: Global MASTER-Net observations report DATE: 21/12/08 20:39:17 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, T.Pogrosheva, E.Minkina, A.Chasovnikov, V.Topolev, V.Grinshpun, 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 (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) was pointed to the IceCube Alert 211208.84 (trigger No 21306805,07h 35m 36.48s , +15d 41m 38.4s, R=0.51) errorbox 640 sec after notice time and 682 sec after trigger time at 2021-12-08 20:14:13 UT, with upper limit up to 15.8 mag. The observations began at zenith distance = 45 deg. The sun altitude is -28.1 deg. The galactic latitude b = 17 deg., longitude l = 204 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1808238 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 773 | 2021-12-08 20:14:13 | MASTER-Amur | (07h 34m 50.32s , +15d 18m 50.3s) | C | 180 | 15.8 | 773 | 2021-12-08 20:14:13 | MASTER-Amur | (07h 34m 23.36s , +15d 44m 19.3s) | C | 180 | 14.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.