TITLE: GCN CIRCULAR NUMBER: 29189 SUBJECT: Fermi GRB 201228B: Global MASTER-Net observations report DATE: 20/12/28 16:45:14 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-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 201228B ( Fermi GBM team, GCN 29188) errorbox 1104 sec after notice time and 1136 sec after trigger time at 2020-12-28 15:40:42 UT, with upper limit up to 18.8 mag. Observations started at twilight. The observations began at zenith distance = 4 deg. The sun altitude is -15.3 deg. The galactic latitude b = -12 deg., longitude l = 120 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1513509 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 1227 | 2020-12-28 15:40:42 | MASTER-Tavrida | (00h 39m 42.51s , +41d 18m 49.9s) | C | 180 | 18.8 | 1227 | 2020-12-28 15:40:42 | MASTER-Tavrida | (00h 39m 21.36s , +41d 17m 02.5s) | C | 180 | 18.2 | 1426 | 2020-12-28 15:44:02 | MASTER-Tavrida | (00h 39m 44.66s , +41d 20m 13.1s) | C | 180 | 18.8 | 1566 | 2020-12-28 15:47:21 | MASTER-Tavrida | (00h 39m 44.39s , +41d 20m 10.4s) | C | 60 | 18.2 | 1566 | 2020-12-28 15:47:21 | MASTER-Tavrida | (00h 39m 22.94s , +41d 18m 23.7s) | C | 60 | 18.4 | 2262 | 2020-12-28 15:58:58 | MASTER-Tavrida | (23h 56m 43.97s , +48d 01m 31.2s) | C | 60 | 17.9 | 2262 | 2020-12-28 15:58:58 | MASTER-Tavrida | (23h 56m 19.28s , +47d 59m 37.6s) | C | 60 | 17.8 | 2342 | 2020-12-28 16:00:17 | MASTER-Tavrida | (23h 56m 15.68s , +54d 03m 05.9s) | C | 60 | 17.2 | 2342 | 2020-12-28 16:00:17 | MASTER-Tavrida | (23h 55m 46.62s , +54d 01m 09.4s) | C | 60 | 17.3 | 2500 | 2020-12-28 16:02:56 | MASTER-Tavrida | (23h 56m 47.04s , +46d 02m 54.9s) | C | 60 | 17.9 | 2501 | 2020-12-28 16:02:56 | MASTER-Tavrida | (23h 56m 22.59s , +46d 00m 58.5s) | C | 60 | 17.9 | 2759 | 2020-12-28 16:07:14 | MASTER-Tavrida | (01h 05m 16.31s , +50d 04m 07.5s) | C | 60 | 18.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.