TITLE: GCN CIRCULAR NUMBER: 25910 SUBJECT: IceCube Alert 191001.84: Global MASTER-Net observations report DATE: 19/10/01 20:28:03 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (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) was pointed to the IceCube Alert 191001.84 (20h 57m 25.200s , +12d 34m 31.80s, R=0.7867) errorbox 55 sec after trigger time at 2019-10-01 20:10:14 UT, with upper limit up to 20.0 mag. The observations began at zenit distance = 48 deg. The sun altitude is -41.9 deg. MASTER-IAC robotic telescope located in Spain (IAC Teide Observatory) was pointed to the IceCube Alert 191001.84 errorbox 86 sec after trigger time at 2019-10-01 20:10:45 UT, with upper limit up to 19.0 mag. The observations began at zenit distance = 22 deg. The sun altitude is -18.7 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1153994 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 146 | 2019-10-01 20:10:14 | MASTER-SAAO | (20h 57m 07.155s , +12d 35m 09.78s) | C | 180 | 20.0 | 97 | 2019-10-01 20:10:45 | MASTER-IAC | (20h 56m 31.124s , +12d 30m 35.93s) | P| | 20 | 17.5 | 97 | 2019-10-01 20:10:45 | MASTER-IAC | (20h 55m 50.004s , +12d 34m 14.43s) | P- | 20 | 17.1 | 143 | 2019-10-01 20:11:26 | MASTER-IAC | (20h 56m 31.110s , +12d 30m 37.13s) | P| | 30 | 17.8 | 143 | 2019-10-01 20:11:26 | MASTER-IAC | (20h 55m 50.002s , +12d 34m 16.22s) | P- | 30 | 17.5 | 197 | 2019-10-01 20:12:15 | MASTER-IAC | (20h 55m 49.990s , +12d 34m 17.20s) | P- | 40 | 17.7 | 197 | 2019-10-01 20:12:15 | MASTER-IAC | (20h 56m 31.097s , +12d 30m 38.25s) | P| | 40 | 18.1 | 260 | 2019-10-01 20:13:13 | MASTER-IAC | (20h 56m 31.079s , +12d 30m 39.26s) | P| | 50 | 18.3 | 260 | 2019-10-01 20:13:13 | MASTER-IAC | (20h 55m 49.972s , +12d 34m 18.00s) | P- | 50 | 17.9 | 334 | 2019-10-01 20:14:21 | MASTER-IAC | (20h 55m 49.964s , +12d 34m 18.65s) | P- | 60 | 18.0 | 334 | 2019-10-01 20:14:22 | MASTER-IAC | (20h 56m 31.082s , +12d 30m 40.13s) | P| | 60 | 18.4 | 424 | 2019-10-01 20:15:41 | MASTER-IAC | (20h 56m 31.085s , +12d 30m 40.80s) | P| | 80 | 18.7 | 424 | 2019-10-01 20:15:41 | MASTER-IAC | (20h 55m 49.935s , +12d 34m 19.16s) | P- | 80 | 18.2 | 531 | 2019-10-01 20:17:19 | MASTER-IAC | (20h 55m 49.889s , +12d 34m 19.46s) | P- | 100 | 18.5 | 531 | 2019-10-01 20:17:19 | MASTER-IAC | (20h 56m 31.085s , +12d 30m 41.37s) | P| | 100 | 19.0 | 660 | 2019-10-01 20:19:17 | MASTER-IAC | (20h 55m 49.831s , +12d 34m 19.51s) | P- | 120 | 18.6 | 660 | 2019-10-01 20:19:18 | MASTER-IAC | (20h 56m 31.088s , +12d 30m 41.66s) | P| | 120 | 19.0 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.