TITLE: GCN CIRCULAR NUMBER: 31655 SUBJECT: Fermi trigger No 667737010: Global MASTER-Net observations report DATE: 22/02/28 13:30:15 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), B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez, M.L.H.Rodriguez (INAOE, OAGH) A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-OAGH robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB220228.44 (trigger No 667737010,20h 11m 24.00s , -02d 54m 00.0s, R=24.98) errorbox 9538 sec after notice time and 9569 sec after trigger time at 2022-02-28 13:09:35 UT, with upper limit up to 12.3 mag. Observations started at twilight. The observations began at zenith distance = 52 deg. The sun altitude is -8.7 deg. The galactic latitude b = -20 deg., longitude l = 40 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1897065 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 9600 | 2022-02-28 13:09:35 | MASTER-OAGH | (19h 44m 16.08s , +08d 48m 07.0s) | C | 60 | 12.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.