TITLE: GCN CIRCULAR NUMBER: 31523 SUBJECT: Fermi trigger No 664738369: Global MASTER-Net observations report DATE: 22/01/25 00:15:35 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-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 GRB220124.73 (trigger No 664738369,15h 36m 43.20s , -46d 38m 24.0s, R=5.08) errorbox 22659 sec after notice time and 22686 sec after trigger time at 2022-01-24 23:50:50 UT, with upper limit up to 17.4 mag. The observations began at zenith distance = 69 deg. The sun altitude is -36.9 deg. The galactic latitude b = 7 deg., longitude l = 331 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1859424 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 22716 | 2022-01-24 23:50:50 | MASTER-SAAO | (15h 40m 50.18s , -48d 11m 29.0s) | C | 60 | 17.3 | 22796 | 2022-01-24 23:52:10 | MASTER-SAAO | (15h 28m 56.26s , -48d 12m 23.0s) | C | 60 | 17.1 | 22876 | 2022-01-24 23:53:30 | MASTER-SAAO | (15h 40m 11.99s , -46d 19m 14.7s) | C | 60 | 17.2 | 22955 | 2022-01-24 23:54:49 | MASTER-SAAO | (15h 51m 43.86s , -46d 17m 51.9s) | C | 60 | 17.4 | 23035 | 2022-01-24 23:56:09 | MASTER-SAAO | (15h 30m 25.59s , -44d 23m 51.4s) | C | 60 | 17.4 | 23115 | 2022-01-24 23:57:29 | MASTER-SAAO | (15h 41m 31.19s , -44d 24m 36.9s) | C | 60 | 17.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.