TITLE: GCN CIRCULAR NUMBER: 43373 SUBJECT: IceCube Alert 260111.84: Global MASTER-Net observations report DATE: 26/01/11 20:39:22 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru> V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko, G.Antipov, A.Sankovich, Yu.Tselik, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU), O.Gress, N.Budnev (ISU), C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A.Sosnovskij (CrAO), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity), D.Buckley (SAAO), R.Rebolo (The Instituto de Astrofisica de Canarias), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory) MASTER-Kislovodsk robotic telescope [1] located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the IceCube Alert 260111.84 (trigger No 3811884,04h 44m 30.72s , +35d 03m 43.2s, R=0.51) errorbox 12 sec after notice time and 58 sec after trigger time at 2026-01-11 20:11:32 UT, with upper limit up to 19.2 mag. The observations began at zenith distance = 21 deg. The sun altitude is -64.6 deg. MASTER-Tunka robotic telescope located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the IceCube Alert 260111.84 errorbox 26 sec after notice time and 72 sec after trigger time at 2026-01-11 20:11:46 UT, with upper limit up to 14.1 mag. The observations began at zenith distance = 61 deg. The sun altitude is -44.9 deg. MASTER-SAAO robotic telescope located in South Africa (South African Astronomical Observatory) was pointed to the IceCube Alert 260111.84 errorbox 61 sec after notice time and 107 sec after trigger time at 2026-01-11 20:12:21 UT, with upper limit up to 18.9 mag. The observations began at zenith distance = 67 deg. The sun altitude is -24.8 deg. The galactic latitude b = -6 deg., longitude l = 168 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3100219 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 64 | 2026-01-11 20:11:32 | MASTER-Kislovodsk | (04h 43m 04.86s , +35d 34m 12.2s) | P| | 10 | 15.9 | 64 | 2026-01-11 20:11:32 | MASTER-Kislovodsk | (04h 43m 29.08s , +35d 12m 14.1s) | C | 10 | 16.9 | 89 | 2026-01-11 20:11:32 | MASTER-Kislovodsk | (04h 43m 29.08s , +35d 12m 14.1s) | C | 60 | 18.0 | Coadd 78 | 2026-01-11 20:11:46 | MASTER-Tunka | (04h 43m 38.90s , +35d 16m 36.1s) | P- | 10 | 14.1 | 78 | 2026-01-11 20:11:46 | MASTER-Tunka | (04h 43m 07.38s , +35d 23m 28.3s) | P| | 10 | 13.0 | 99 | 2026-01-11 20:12:02 | MASTER-Kislovodsk | (04h 43m 04.82s , +35d 34m 09.7s) | P| | 20 | 16.4 | 99 | 2026-01-11 20:12:02 | MASTER-Kislovodsk | (04h 43m 29.04s , +35d 12m 12.1s) | C | 20 | 17.4 | 118 | 2026-01-11 20:12:21 | MASTER-SAAO | (04h 42m 05.60s , +34d 48m 35.2s) | C | 20 | 18.0 | 153 | 2026-01-11 20:12:21 | MASTER-SAAO | (04h 42m 05.60s , +34d 48m 35.2s) | C | 90 | 18.9 | 118 | 2026-01-11 20:12:21 | MASTER-SAAO | (04h 40m 03.11s , +35d 04m 27.6s) | C | 20 | 17.8 | 153 | 2026-01-11 20:12:21 | MASTER-SAAO | (04h 40m 03.11s , +35d 04m 27.6s) | C | 90 | 18.8 | 145 | 2026-01-11 20:12:43 | MASTER-Kislovodsk | (04h 43m 28.95s , +35d 12m 09.1s) | C | 30 | 17.8 | 145 | 2026-01-11 20:12:43 | MASTER-Kislovodsk | (04h 43m 04.76s , +35d 34m 06.1s) | P| | 30 | 17.0 | 162 | 2026-01-11 20:13:01 | MASTER-SAAO | (04h 42m 05.86s , +34d 48m 37.9s) | C | 30 | 18.3 | 162 | 2026-01-11 20:13:01 | MASTER-SAAO | (04h 40m 03.42s , +35d 04m 31.2s) | C | 30 | 18.2 | 200 | 2026-01-11 20:13:33 | MASTER-Kislovodsk | (04h 43m 04.72s , +35d 34m 02.5s) | P| | 40 | 16.9 | 200 | 2026-01-11 20:13:33 | MASTER-Kislovodsk | (04h 43m 28.88s , +35d 12m 06.2s) | C | 40 | 17.9 | 255 | 2026-01-11 20:13:33 | MASTER-Kislovodsk | (04h 43m 28.89s , +35d 12m 06.1s) | C | 150 | 18.7 | Coadd 216 | 2026-01-11 20:13:49 | MASTER-SAAO | (04h 42m 06.14s , +34d 48m 40.7s) | C | 40 | 18.4 | 216 | 2026-01-11 20:13:50 | MASTER-SAAO | (04h 40m 03.68s , +35d 04m 34.5s) | C | 40 | 18.2 | 265 | 2026-01-11 20:14:33 | MASTER-Kislovodsk | (04h 43m 04.64s , +35d 33m 58.2s) | P| | 50 | 17.1 | 265 | 2026-01-11 20:14:33 | MASTER-Kislovodsk | (04h 43m 28.78s , +35d 12m 02.4s) | C | 50 | 18.0 | 280 | 2026-01-11 20:14:49 | MASTER-SAAO | (04h 42m 06.49s , +34d 48m 43.7s) | C | 50 | 18.5 | 280 | 2026-01-11 20:14:49 | MASTER-SAAO | (04h 40m 03.97s , +35d 04m 38.1s) | C | 50 | 18.4 | 341 | 2026-01-11 20:15:44 | MASTER-Kislovodsk | (04h 43m 28.69s , +35d 11m 58.8s) | C | 60 | 18.2 | 341 | 2026-01-11 20:15:44 | MASTER-Kislovodsk | (04h 43m 04.53s , +35d 33m 54.1s) | P| | 60 | 17.4 | 354 | 2026-01-11 20:15:58 | MASTER-SAAO | (04h 42m 06.82s , +34d 48m 46.7s) | C | 60 | 18.8 | 354 | 2026-01-11 20:15:58 | MASTER-SAAO | (04h 40m 04.29s , +35d 04m 41.7s) | C | 60 | 18.5 | 432 | 2026-01-11 20:17:05 | MASTER-Kislovodsk | (04h 43m 04.39s , +35d 33m 49.7s) | P| | 80 | 17.4 | 432 | 2026-01-11 20:17:05 | MASTER-Kislovodsk | (04h 43m 28.56s , +35d 11m 55.0s) | C | 80 | 18.4 | 542 | 2026-01-11 20:17:05 | MASTER-Kislovodsk | (04h 43m 28.56s , +35d 11m 54.9s) | C | 300 | 19.2 | Coadd 433 | 2026-01-11 20:17:17 | MASTER-SAAO | (04h 42m 07.12s , +34d 48m 50.4s) | C | 60 | 18.7 | 433 | 2026-01-11 20:17:17 | MASTER-SAAO | (04h 40m 04.61s , +35d 04m 45.6s) | C | 60 | 18.6 | 513 | 2026-01-11 20:18:36 | MASTER-SAAO | (04h 42m 07.48s , +34d 48m 53.0s) | C | 60 | 18.8 | 513 | 2026-01-11 20:18:36 | MASTER-SAAO | (04h 40m 04.97s , +35d 04m 48.8s) | C | 60 | 18.6 | 552 | 2026-01-11 20:18:56 | MASTER-Kislovodsk | (04h 43m 28.37s , +35d 11m 50.5s) | C | 100 | 18.4 | 552 | 2026-01-11 20:18:56 | MASTER-Kislovodsk | (04h 43m 04.21s , +35d 33m 44.7s) | P| | 100 | 17.6 | 592 | 2026-01-11 20:19:55 | MASTER-SAAO | (04h 42m 07.81s , +34d 48m 55.7s) | C | 60 | 18.8 | 592 | 2026-01-11 20:19:55 | MASTER-SAAO | (04h 40m 05.29s , +35d 04m 51.9s) | C | 60 | 18.6 | 683 | 2026-01-11 20:20:56 | MASTER-Kislovodsk | (04h 43m 04.05s , +35d 33m 39.6s) | P| | 120 | 17.6 | 683 | 2026-01-11 20:20:56 | MASTER-Kislovodsk | (04h 43m 28.20s , +35d 11m 46.1s) | C | 120 | 18.4 | 671 | 2026-01-11 20:21:14 | MASTER-SAAO | (04h 42m 08.14s , +34d 48m 58.6s) | C | 60 | 18.8 | 671 | 2026-01-11 20:21:14 | MASTER-SAAO | (04h 40m 05.62s , +35d 04m 55.0s) | C | 60 | 18.7 | 750 | 2026-01-11 20:22:33 | MASTER-SAAO | (04h 42m 08.48s , +34d 49m 01.7s) | C | 60 | 18.8 | 750 | 2026-01-11 20:22:33 | MASTER-SAAO | (04h 40m 05.95s , +35d 04m 58.4s) | C | 60 | 18.6 | 833 | 2026-01-11 20:23:27 | MASTER-Kislovodsk | (04h 43m 27.94s , +35d 11m 41.5s) | C | 120 | 18.5 | 840 | 2026-01-11 20:23:33 | MASTER-Kislovodsk | (04h 43m 03.83s , +35d 33m 33.8s) | P| | 120 | 17.8 | 829 | 2026-01-11 20:23:52 | MASTER-SAAO | (04h 42m 08.82s , +34d 49m 04.0s) | C | 60 | 18.8 | 829 | 2026-01-11 20:23:52 | MASTER-SAAO | (04h 40m 06.27s , +35d 05m 01.0s) | C | 60 | 18.6 | 981 | 2026-01-11 20:25:54 | MASTER-Kislovodsk | (04h 43m 03.62s , +35d 33m 28.6s) | P| | 120 | 17.6 | 981 | 2026-01-11 20:25:54 | MASTER-Kislovodsk | (04h 43m 27.69s , +35d 11m 36.9s) | C | 120 | 18.4 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. [1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp. http : // www.pereplet.ru/lipunov/625.html View this GCN Circular online at https://gcn.nasa.gov/circulars/43373. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...