TITLE: GCN CIRCULAR NUMBER: 33105 SUBJECT: Fermi GRB 221226A: Global MASTER-Net observations report DATE: 22/12/26 19:15:18 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, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (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), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 221226A ( Fermi GBM team, GCN 33104) errorbox 6665 sec after notice time and 6700 sec after trigger time at 2022-12-26 18:36:07 UT, with upper limit up to 18.0 mag. Observations started at twilight. The observations began at zenith distance = 76 deg. The sun altitude is -9.8 deg. The galactic latitude b = -8 deg., longitude l = 166 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2187618 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 6730 | 2022-12-26 18:36:07 | MASTER-SAAO | (04h 44m 22.09s , +35d 17m 23.9s) | C | 60 | 15.0 | 6810 | 2022-12-26 18:37:27 | MASTER-SAAO | (04h 28m 26.64s , +33d 24m 58.1s) | C | 60 | 15.8 | 6980 | 2022-12-26 18:40:16 | MASTER-SAAO | (04h 25m 49.17s , +35d 17m 58.7s) | C | 60 | 16.1 | 7071 | 2022-12-26 18:41:48 | MASTER-SAAO | (04h 22m 22.24s , +37d 11m 21.9s) | C | 60 | 16.4 | 7162 | 2022-12-26 18:43:19 | MASTER-SAAO | (04h 32m 21.78s , +37d 12m 39.9s) | C | 60 | 16.6 | 7412 | 2022-12-26 18:47:29 | MASTER-SAAO | (04h 41m 26.03s , +37d 12m 15.3s) | C | 60 | 16.8 | 7583 | 2022-12-26 18:50:19 | MASTER-SAAO | (04h 38m 01.88s , +33d 23m 26.3s) | C | 60 | 17.2 | 7674 | 2022-12-26 18:51:51 | MASTER-SAAO | (04h 34m 37.01s , +35d 19m 08.3s) | C | 60 | 17.3 | 7764 | 2022-12-26 18:53:20 | MASTER-SAAO | (04h 44m 24.37s , +35d 17m 47.7s) | C | 60 | 17.2 | 7844 | 2022-12-26 18:54:40 | MASTER-SAAO | (04h 28m 29.31s , +33d 24m 59.4s) | C | 60 | 17.3 | 8014 | 2022-12-26 18:57:30 | MASTER-SAAO | (04h 25m 46.26s , +35d 19m 15.9s) | C | 60 | 17.4 | 8104 | 2022-12-26 18:59:01 | MASTER-SAAO | (04h 22m 25.82s , +37d 12m 14.8s) | C | 60 | 17.8 | 8195 | 2022-12-26 19:00:31 | MASTER-SAAO | (04h 32m 20.32s , +37d 11m 24.2s) | C | 60 | 17.7 | 8444 | 2022-12-26 19:04:41 | MASTER-SAAO | (04h 41m 26.27s , +37d 11m 56.5s) | C | 60 | 17.7 | 8615 | 2022-12-26 19:07:32 | MASTER-SAAO | (04h 37m 58.66s , +33d 24m 36.4s) | C | 60 | 18.0 | 8706 | 2022-12-26 19:09:02 | MASTER-SAAO | (04h 34m 35.73s , +35d 19m 35.3s) | C | 60 | 18.0 | 8785 | 2022-12-26 19:10:22 | MASTER-SAAO | (04h 44m 29.63s , +35d 18m 45.8s) | C | 60 | 18.0 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.