TITLE: GCN CIRCULAR NUMBER: 31956 SUBJECT: Fermi GRB 220426A: Global MASTER-Net observations report DATE: 22/04/27 04:30:33 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-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 GRB 220426A ( C. Malacaria et al., GCN 31955) errorbox 13914 sec after notice time and 13944 sec after trigger time at 2022-04-26 10:42:15 UT, with upper limit up to 18.2 mag. The observations began at zenith distance = 87 deg. The sun altitude is -23.6 deg. The galactic latitude b = -57 deg., longitude l = 33 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1954577 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 13974 | 2022-04-26 10:42:15 | MASTER-OAGH | (22h 26m 58.35s , -22d 47m 13.6s) | C | 60 | 14.0 | 13974 | 2022-04-26 10:42:15 | MASTER-OAGH | (22h 18m 46.43s , -23d 14m 51.0s) | C | 60 | 14.2 | 14195 | 2022-04-26 10:45:55 | MASTER-OAGH | (22h 27m 04.78s , -22d 46m 50.5s) | C | 60 | 14.4 | 14195 | 2022-04-26 10:45:55 | MASTER-OAGH | (22h 18m 53.88s , -23d 14m 54.4s) | C | 60 | 14.3 | 14416 | 2022-04-26 10:49:36 | MASTER-OAGH | (22h 27m 01.55s , -22d 45m 08.6s) | C | 60 | 14.7 | 14416 | 2022-04-26 10:49:36 | MASTER-OAGH | (22h 18m 52.02s , -23d 13m 27.6s) | C | 60 | 14.4 | 14638 | 2022-04-26 10:53:19 | MASTER-OAGH | (22h 27m 01.61s , -22d 46m 16.7s) | C | 60 | 15.0 | 14638 | 2022-04-26 10:53:19 | MASTER-OAGH | (22h 18m 53.98s , -23d 13m 57.4s) | C | 60 | 14.4 | 15069 | 2022-04-26 11:00:29 | MASTER-OAGH | (22h 26m 59.82s , -22d 44m 34.8s) | C | 60 | 13.5 | 15069 | 2022-04-26 11:00:29 | MASTER-OAGH | (22h 18m 47.92s , -23d 13m 32.3s) | C | 60 | 15.3 | 15399 | 2022-04-26 11:05:59 | MASTER-OAGH | (22h 26m 59.62s , -22d 44m 54.8s) | C | 60 | 16.0 | 15399 | 2022-04-26 11:05:59 | MASTER-OAGH | (22h 18m 51.90s , -23d 13m 10.4s) | C | 60 | 15.5 | 15621 | 2022-04-26 11:09:42 | MASTER-OAGH | (22h 27m 05.08s , -22d 45m 53.1s) | C | 60 | 15.9 | 15621 | 2022-04-26 11:09:42 | MASTER-OAGH | (22h 18m 57.09s , -23d 14m 19.4s) | C | 60 | 15.3 | 15843 | 2022-04-26 11:13:23 | MASTER-OAGH | (22h 27m 00.35s , -22d 46m 49.8s) | C | 60 | 16.0 | 15843 | 2022-04-26 11:13:23 | MASTER-OAGH | (22h 18m 53.16s , -23d 14m 44.6s) | C | 60 | 15.2 | 16335 | 2022-04-26 11:20:36 | MASTER-OAGH | (22h 27m 03.19s , -22d 44m 58.7s) | C | 180 | 16.9 | 16335 | 2022-04-26 11:20:36 | MASTER-OAGH | (22h 18m 54.54s , -23d 13m 07.3s) | C | 180 | 16.1 | 16677 | 2022-04-26 11:26:18 | MASTER-OAGH | (22h 27m 03.75s , -22d 46m 34.8s) | C | 180 | 18.1 | 16677 | 2022-04-26 11:26:18 | MASTER-OAGH | (22h 18m 54.96s , -23d 14m 42.0s) | C | 180 | 18.0 | 17018 | 2022-04-26 11:31:59 | MASTER-OAGH | (22h 27m 07.01s , -22d 45m 21.0s) | C | 180 | 18.2 | 17018 | 2022-04-26 11:31:59 | MASTER-OAGH | (22h 18m 58.09s , -23d 13m 28.3s) | C | 180 | 18.1 | 17360 | 2022-04-26 11:37:41 | MASTER-OAGH | (22h 27m 01.27s , -22d 45m 58.8s) | C | 180 | 18.2 | 17360 | 2022-04-26 11:37:41 | MASTER-OAGH | (22h 18m 52.06s , -23d 14m 06.9s) | C | 180 | 18.0 | 17703 | 2022-04-26 11:43:23 | MASTER-OAGH | (22h 27m 02.75s , -22d 44m 59.6s) | C | 180 | 17.6 | 17703 | 2022-04-26 11:43:23 | MASTER-OAGH | (22h 18m 53.37s , -23d 13m 07.8s) | C | 180 | 17.6 | 18045 | 2022-04-26 11:49:05 | MASTER-OAGH | (22h 27m 08.28s , -22d 46m 00.6s) | C | 180 | 16.9 | 18045 | 2022-04-26 11:49:05 | MASTER-OAGH | (22h 18m 58.55s , -23d 14m 08.2s) | C | 180 | 16.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.