TITLE: GCN CIRCULAR NUMBER: 31678 SUBJECT: IceCube Alert 220304.74: Global MASTER-Net observations report DATE: 22/03/04 18:39:39 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 IceCube Alert 220304.74 (trigger No 4701751,03h 15m 19.20s , +04d 27m 50.4s, R=1.25) errorbox 399 sec after notice time and 452 sec after trigger time at 2022-03-04 17:51:44 UT, with upper limit up to 19.3 mag. Observations started at twilight. The observations began at zenith distance = 54 deg. The sun altitude is -9.4 deg. The galactic latitude b = -42 deg., longitude l = 177 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1902082 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 478 | 2022-03-04 17:51:44 | MASTER-SAAO | (03h 15m 25.92s , +04d 21m 56.3s) | C | 50 | 16.4 | 618 | 2022-03-04 17:51:44 | MASTER-SAAO | (03h 15m 25.92s , +04d 21m 56.3s) | C | 330 | 17.5 | Coadd 572 | 2022-03-04 17:52:54 | MASTER-SAAO | (03h 15m 22.53s , +04d 23m 34.3s) | C | 100 | 16.6 | 980 | 2022-03-04 17:59:02 | MASTER-SAAO | (03h 15m 17.23s , +04d 21m 55.3s) | C | 180 | 17.3 | 1180 | 2022-03-04 18:02:22 | MASTER-SAAO | (03h 15m 23.33s , +04d 22m 05.8s) | C | 180 | 17.9 | 1379 | 2022-03-04 18:05:41 | MASTER-SAAO | (03h 15m 19.93s , +04d 24m 00.7s) | C | 180 | 18.5 | 1579 | 2022-03-04 18:09:01 | MASTER-SAAO | (03h 15m 19.45s , +04d 22m 22.8s) | C | 180 | 18.8 | 1779 | 2022-03-04 18:12:20 | MASTER-SAAO | (03h 15m 21.63s , +04d 24m 10.7s) | C | 180 | 18.8 | 2083 | 2022-03-04 18:18:24 | MASTER-SAAO | (03h 14m 17.07s , +04d 54m 40.3s) | C | 60 | 17.4 | 2329 | 2022-03-04 18:22:30 | MASTER-SAAO | (03h 22m 21.30s , +04d 54m 46.9s) | C | 60 | 19.3 | 2408 | 2022-03-04 18:23:50 | MASTER-SAAO | (03h 13m 48.57s , +03d 01m 53.2s) | C | 60 | 19.1 | 2573 | 2022-03-04 18:26:34 | MASTER-SAAO | (03h 21m 56.33s , +03d 01m 52.0s) | C | 60 | 19.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.