TITLE: GCN CIRCULAR NUMBER: 31832 SUBJECT: IceCube Alert 220405.21: Global MASTER-Net observations report DATE: 22/04/05 05:39:32 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) was pointed to the IceCube Alert 220405.21 (trigger No 1833389,08h 58m 35.28s , -01d 13m 04.8s, R=0.65) errorbox 19 sec after notice time and 72 sec after trigger time at 2022-04-05 04:58:38 UT, with upper limit up to 18.4 mag. The observations began at zenith distance = 40 deg. The sun altitude is -39.7 deg. The galactic latitude b = 28 deg., longitude l = 230 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1933135 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 78 | 2022-04-05 04:58:38 | MASTER-OAGH | (08h 54m 34.29s , -01d 12m 46.4s) | C | 10 | 15.9 | 78 | 2022-04-05 04:58:38 | MASTER-OAGH | (08h 54m 07.08s , -00d 44m 08.9s) | P- | 10 | 15.7 | 114 | 2022-04-05 04:59:09 | MASTER-OAGH | (08h 54m 34.25s , -01d 13m 50.3s) | C | 20 | 16.7 | 114 | 2022-04-05 04:59:09 | MASTER-OAGH | (08h 54m 06.99s , -00d 45m 13.1s) | P- | 20 | 16.3 | 160 | 2022-04-05 04:59:51 | MASTER-OAGH | (08h 54m 36.30s , -01d 12m 32.0s) | C | 30 | 16.4 | 160 | 2022-04-05 04:59:51 | MASTER-OAGH | (08h 54m 09.03s , -00d 43m 55.0s) | P- | 30 | 16.5 | 216 | 2022-04-05 05:00:42 | MASTER-OAGH | (08h 54m 31.27s , -01d 13m 19.2s) | C | 40 | 16.6 | 216 | 2022-04-05 05:00:42 | MASTER-OAGH | (08h 54m 03.99s , -00d 44m 41.8s) | P- | 40 | 16.7 | 283 | 2022-04-05 05:01:44 | MASTER-OAGH | (08h 54m 31.23s , -01d 12m 20.0s) | C | 50 | 17.0 | 283 | 2022-04-05 05:01:44 | MASTER-OAGH | (08h 54m 03.93s , -00d 43m 43.1s) | P- | 50 | 17.0 | 365 | 2022-04-05 05:02:55 | MASTER-OAGH | (08h 54m 10.01s , -00d 44m 42.4s) | P- | 70 | 17.3 | 365 | 2022-04-05 05:02:55 | MASTER-OAGH | (08h 54m 37.35s , -01d 13m 21.0s) | C | 70 | 17.4 | 461 | 2022-04-05 05:04:27 | MASTER-OAGH | (08h 54m 31.37s , -01d 14m 20.8s) | C | 80 | 17.4 | 461 | 2022-04-05 05:04:27 | MASTER-OAGH | (08h 54m 03.99s , -00d 45m 43.0s) | P- | 80 | 17.5 | 572 | 2022-04-05 05:06:08 | MASTER-OAGH | (08h 54m 10.03s , -00d 45m 30.1s) | P- | 100 | 17.7 | 572 | 2022-04-05 05:06:08 | MASTER-OAGH | (08h 54m 37.47s , -01d 14m 08.1s) | C | 100 | 18.4 | 708 | 2022-04-05 05:08:09 | MASTER-OAGH | (08h 54m 34.63s , -01d 12m 46.2s) | C | 130 | 17.9 | 708 | 2022-04-05 05:08:09 | MASTER-OAGH | (08h 54m 07.11s , -00d 44m 08.2s) | P- | 130 | 17.8 | 878 | 2022-04-05 05:10:44 | MASTER-OAGH | (08h 54m 34.81s , -01d 14m 07.6s) | C | 160 | 17.7 | 878 | 2022-04-05 05:10:44 | MASTER-OAGH | (08h 54m 07.20s , -00d 45m 29.6s) | P- | 160 | 17.8 | 1070 | 2022-04-05 05:13:45 | MASTER-OAGH | (08h 54m 38.08s , -01d 12m 29.3s) | C | 180 | 18.2 | 1070 | 2022-04-05 05:13:45 | MASTER-OAGH | (08h 54m 10.33s , -00d 43m 51.1s) | P- | 180 | 17.9 | 1271 | 2022-04-05 05:17:07 | MASTER-OAGH | (08h 54m 32.31s , -01d 13m 24.8s) | C | 180 | 17.5 | 1271 | 2022-04-05 05:17:07 | MASTER-OAGH | (08h 54m 04.44s , -00d 44m 45.8s) | P- | 180 | 17.7 | 1473 | 2022-04-05 05:20:29 | MASTER-OAGH | (08h 54m 32.47s , -01d 12m 26.0s) | C | 180 | 17.9 | 1473 | 2022-04-05 05:20:29 | MASTER-OAGH | (08h 54m 04.49s , -00d 43m 47.4s) | P- | 180 | 17.7 | 1699 | 2022-04-05 05:24:14 | MASTER-OAGH | (08h 54m 38.79s , -01d 13m 25.9s) | C | 180 | 17.9 | 1699 | 2022-04-05 05:24:14 | MASTER-OAGH | (08h 54m 10.67s , -00d 44m 46.8s) | P- | 180 | 17.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.