TITLE: GCN CIRCULAR NUMBER: 43848 SUBJECT: LAT GRB260226.44: Global MASTER-Net observations report DATE: 26/02/26 15:44:21 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-Tunka robotic telescope [1] located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the LAT GRB260226.44 (trigger No 793795080,02h 47m 41.04s , +07d 43m 12.0s, R=0.105833) errorbox 16332 sec after trigger time at 2026-02-26 15:10:31 UT, with upper limit up to 17.0 mag. The observations began at zenith distance = 81 deg. The sun altitude is -40.1 deg. The galactic latitude b = -45 deg., longitude l = 167 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3157390 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 16337 | 2026-02-26 15:10:31 | MASTER-Tunka | (02h 46m 41.03s , +08d 13m 10.9s) | C | 10 | 16.4 | 16347 | 2026-02-26 15:10:31 | MASTER-Tunka | (02h 46m 41.03s , +08d 13m 11.0s) | C | 30 | 17.0 | Coadd 16338 | 2026-02-26 15:10:31 | MASTER-Tunka | (02h 46m 22.49s , +08d 16m 39.4s) | C | 10 | 16.0 | 16362 | 2026-02-26 15:10:56 | MASTER-Tunka | (02h 46m 34.45s , +08d 12m 33.1s) | C | 10 | 16.5 | 16363 | 2026-02-26 15:10:56 | MASTER-Tunka | (02h 46m 16.08s , +08d 15m 59.0s) | C | 10 | 15.8 | 16384 | 2026-02-26 15:11:18 | MASTER-Tunka | (02h 46m 33.55s , +08d 13m 32.1s) | C | 10 | 16.4 | 16384 | 2026-02-26 15:11:18 | MASTER-Tunka | (02h 46m 15.50s , +08d 16m 58.7s) | C | 10 | 16.0 | 16408 | 2026-02-26 15:11:41 | MASTER-Tunka | (02h 46m 40.83s , +08d 12m 31.4s) | C | 10 | 16.4 | 16408 | 2026-02-26 15:11:41 | MASTER-Tunka | (02h 46m 22.76s , +08d 15m 57.8s) | C | 10 | 15.9 | 16430 | 2026-02-26 15:12:04 | MASTER-Tunka | (02h 46m 33.93s , +08d 11m 31.6s) | C | 10 | 16.3 | 16431 | 2026-02-26 15:12:04 | MASTER-Tunka | (02h 46m 15.91s , +08d 14m 57.9s) | C | 10 | 15.8 | 16454 | 2026-02-26 15:12:27 | MASTER-Tunka | (02h 46m 40.26s , +08d 11m 42.7s) | C | 10 | 16.1 | 16454 | 2026-02-26 15:12:27 | MASTER-Tunka | (02h 46m 22.16s , +08d 15m 07.0s) | C | 10 | 15.3 | 16478 | 2026-02-26 15:12:52 | MASTER-Tunka | (02h 46m 37.35s , +08d 12m 56.4s) | C | 10 | 15.0 | 16479 | 2026-02-26 15:12:52 | MASTER-Tunka | (02h 46m 19.39s , +08d 16m 23.6s) | C | 10 | 14.8 | 16503 | 2026-02-26 15:13:17 | MASTER-Tunka | (02h 46m 37.23s , +08d 11m 26.2s) | C | 10 | 14.7 | 16503 | 2026-02-26 15:13:17 | MASTER-Tunka | (02h 46m 19.51s , +08d 14m 56.8s) | C | 10 | 14.6 | 16526 | 2026-02-26 15:13:40 | MASTER-Tunka | (02h 46m 39.73s , +08d 13m 11.3s) | C | 10 | 15.8 | 16527 | 2026-02-26 15:13:40 | MASTER-Tunka | (02h 46m 21.80s , +08d 16m 35.6s) | C | 10 | 15.2 | 16550 | 2026-02-26 15:14:03 | MASTER-Tunka | (02h 46m 33.44s , +08d 12m 29.2s) | C | 10 | 15.3 | 16550 | 2026-02-26 15:14:03 | MASTER-Tunka | (02h 46m 15.66s , +08d 15m 55.3s) | C | 10 | 14.9 | 16576 | 2026-02-26 15:14:30 | MASTER-Tunka | (02h 46m 34.78s , +08d 13m 28.4s) | C | 10 | 15.3 | 16577 | 2026-02-26 15:14:30 | MASTER-Tunka | (02h 46m 17.03s , +08d 16m 54.9s) | C | 10 | 15.1 | 16607 | 2026-02-26 15:15:01 | MASTER-Tunka | (02h 46m 40.60s , +08d 12m 25.3s) | C | 10 | 15.4 | 16607 | 2026-02-26 15:15:01 | MASTER-Tunka | (02h 46m 22.93s , +08d 15m 51.3s) | C | 10 | 14.9 | 16630 | 2026-02-26 15:15:23 | MASTER-Tunka | (02h 46m 33.66s , +08d 11m 26.0s) | C | 10 | 15.4 | 16630 | 2026-02-26 15:15:23 | MASTER-Tunka | (02h 46m 16.01s , +08d 14m 52.2s) | C | 10 | 15.1 | 16653 | 2026-02-26 15:15:46 | MASTER-Tunka | (02h 46m 41.11s , +08d 11m 47.9s) | C | 10 | 16.1 | 16653 | 2026-02-26 15:15:46 | MASTER-Tunka | (02h 46m 24.19s , +08d 15m 25.7s) | C | 10 | 14.8 | 16676 | 2026-02-26 15:16:09 | MASTER-Tunka | (02h 46m 37.35s , +08d 13m 13.3s) | C | 10 | 15.6 | 16676 | 2026-02-26 15:16:09 | MASTER-Tunka | (02h 46m 19.66s , +08d 16m 38.3s) | C | 10 | 15.2 | 16832 | 2026-02-26 15:18:43 | MASTER-Tunka | (02h 46m 34.69s , +08d 13m 32.9s) | C | 15 | 16.1 | 16832 | 2026-02-26 15:18:43 | MASTER-Tunka | (02h 46m 16.54s , +08d 16m 52.9s) | C | 15 | 15.5 | 16859 | 2026-02-26 15:19:09 | MASTER-Tunka | (02h 46m 40.75s , +08d 12m 32.7s) | C | 15 | 16.0 | 16859 | 2026-02-26 15:19:09 | MASTER-Tunka | (02h 46m 22.88s , +08d 15m 54.8s) | C | 15 | 15.4 | 16884 | 2026-02-26 15:19:37 | MASTER-Tunka | (02h 46m 35.06s , +08d 11m 32.5s) | C | 10 | 15.8 | 16884 | 2026-02-26 15:19:38 | MASTER-Tunka | (02h 46m 17.19s , +08d 14m 52.2s) | C | 10 | 15.2 | 16908 | 2026-02-26 15:20:02 | MASTER-Tunka | (02h 46m 41.38s , +08d 11m 36.4s) | C | 10 | 16.1 | 16908 | 2026-02-26 15:20:02 | MASTER-Tunka | (02h 46m 23.62s , +08d 14m 57.3s) | C | 10 | 15.4 | 16947 | 2026-02-26 15:20:41 | MASTER-Tunka | (02h 46m 38.12s , +08d 13m 07.4s) | C | 10 | 16.1 | 16947 | 2026-02-26 15:20:41 | MASTER-Tunka | (02h 46m 20.25s , +08d 16m 28.2s) | C | 10 | 15.4 | 16969 | 2026-02-26 15:21:02 | MASTER-Tunka | (02h 46m 38.11s , +08d 11m 37.5s) | C | 10 | 16.0 | 16969 | 2026-02-26 15:21:03 | MASTER-Tunka | (02h 46m 19.74s , +08d 14m 48.1s) | C | 10 | 15.5 | 16993 | 2026-02-26 15:21:26 | MASTER-Tunka | (02h 46m 40.15s , +08d 13m 08.3s) | C | 10 | 15.8 | 16993 | 2026-02-26 15:21:26 | MASTER-Tunka | (02h 46m 22.32s , +08d 16m 29.7s) | C | 10 | 15.3 | 17017 | 2026-02-26 15:21:51 | MASTER-Tunka | (02h 46m 35.71s , +08d 12m 33.0s) | C | 10 | 16.1 | 17017 | 2026-02-26 15:21:51 | MASTER-Tunka | (02h 46m 17.88s , +08d 15m 54.5s) | C | 10 | 15.4 | 17042 | 2026-02-26 15:22:16 | MASTER-Tunka | (02h 46m 35.36s , +08d 13m 30.6s) | C | 10 | 15.9 | 17042 | 2026-02-26 15:22:16 | MASTER-Tunka | (02h 46m 17.46s , +08d 16m 51.1s) | C | 10 | 15.2 | 17068 | 2026-02-26 15:22:41 | MASTER-Tunka | (02h 46m 40.47s , +08d 12m 31.9s) | C | 10 | 15.9 | 17068 | 2026-02-26 15:22:41 | MASTER-Tunka | (02h 46m 22.01s , +08d 15m 41.5s) | C | 10 | 15.5 | 17092 | 2026-02-26 15:23:05 | MASTER-Tunka | (02h 46m 35.02s , +08d 11m 33.0s) | C | 10 | 15.7 | 17092 | 2026-02-26 15:23:05 | MASTER-Tunka | (02h 46m 17.26s , +08d 14m 55.9s) | C | 10 | 15.2 | 17114 | 2026-02-26 15:23:27 | MASTER-Tunka | (02h 46m 41.21s , +08d 11m 47.1s) | C | 10 | 15.8 | 17114 | 2026-02-26 15:23:27 | MASTER-Tunka | (02h 46m 23.36s , +08d 15m 07.6s) | C | 10 | 15.5 | 17139 | 2026-02-26 15:23:52 | MASTER-Tunka | (02h 46m 38.16s , +08d 13m 22.7s) | C | 10 | 15.8 | 17139 | 2026-02-26 15:23:52 | MASTER-Tunka | (02h 46m 19.90s , +08d 16m 35.1s) | C | 10 | 15.3 | 17163 | 2026-02-26 15:24:16 | MASTER-Tunka | (02h 46m 38.13s , +08d 11m 34.8s) | C | 10 | 15.8 | 17163 | 2026-02-26 15:24:16 | MASTER-Tunka | (02h 46m 20.56s , +08d 15m 02.0s) | C | 10 | 15.3 | 17187 | 2026-02-26 15:24:40 | MASTER-Tunka | (02h 46m 41.99s , +08d 13m 24.9s) | C | 10 | 16.0 | 17187 | 2026-02-26 15:24:40 | MASTER-Tunka | (02h 46m 24.35s , +08d 16m 51.1s) | C | 10 | 15.3 | 17209 | 2026-02-26 15:25:03 | MASTER-Tunka | (02h 46m 35.05s , +08d 12m 30.7s) | C | 10 | 15.9 | 17209 | 2026-02-26 15:25:03 | MASTER-Tunka | (02h 46m 17.41s , +08d 15m 58.0s) | C | 10 | 15.2 | 17231 | 2026-02-26 15:25:25 | MASTER-Tunka | (02h 46m 34.52s , +08d 13m 31.1s) | C | 10 | 15.8 | 17231 | 2026-02-26 15:25:25 | MASTER-Tunka | (02h 46m 16.43s , +08d 16m 48.8s) | C | 10 | 15.2 | 17258 | 2026-02-26 15:25:51 | MASTER-Tunka | (02h 46m 41.61s , +08d 12m 31.5s) | C | 10 | 15.8 | 17258 | 2026-02-26 15:25:51 | MASTER-Tunka | (02h 46m 24.00s , +08d 15m 56.3s) | C | 10 | 15.3 | 17281 | 2026-02-26 15:26:14 | MASTER-Tunka | (02h 46m 34.33s , +08d 11m 30.5s) | C | 10 | 15.8 | 17281 | 2026-02-26 15:26:14 | MASTER-Tunka | (02h 46m 16.53s , +08d 14m 52.9s) | C | 10 | 15.2 | 17305 | 2026-02-26 15:26:38 | MASTER-Tunka | (02h 46m 40.80s , +08d 11m 40.7s) | C | 10 | 16.0 | 17305 | 2026-02-26 15:26:38 | MASTER-Tunka | (02h 46m 22.93s , +08d 14m 59.1s) | C | 10 | 15.2 | 17330 | 2026-02-26 15:27:03 | MASTER-Tunka | (02h 46m 37.97s , +08d 13m 22.4s) | C | 10 | 15.7 | 17330 | 2026-02-26 15:27:03 | MASTER-Tunka | (02h 46m 20.40s , +08d 16m 48.5s) | C | 10 | 15.2 | 17355 | 2026-02-26 15:27:29 | MASTER-Tunka | (02h 46m 38.21s , +08d 11m 42.8s) | C | 10 | 15.8 | 17356 | 2026-02-26 15:27:29 | MASTER-Tunka | (02h 46m 20.53s , +08d 15m 06.2s) | C | 10 | 15.2 | 17379 | 2026-02-26 15:27:52 | MASTER-Tunka | (02h 46m 40.47s , +08d 13m 29.7s) | C | 10 | 15.8 | 17379 | 2026-02-26 15:27:52 | MASTER-Tunka | (02h 46m 22.85s , +08d 16m 53.5s) | C | 10 | 15.2 | 17404 | 2026-02-26 15:28:18 | MASTER-Tunka | (02h 46m 34.36s , +08d 12m 28.4s) | C | 10 | 15.8 | 17404 | 2026-02-26 15:28:18 | MASTER-Tunka | (02h 46m 16.62s , +08d 15m 50.9s) | C | 10 | 15.2 | 17428 | 2026-02-26 15:28:41 | MASTER-Tunka | (02h 46m 35.07s , +08d 13m 27.8s) | C | 10 | 15.7 | 17428 | 2026-02-26 15:28:42 | MASTER-Tunka | (02h 46m 17.38s , +08d 16m 50.8s) | C | 10 | 15.1 | 17457 | 2026-02-26 15:29:10 | MASTER-Tunka | (02h 46m 39.98s , +08d 12m 26.4s) | C | 10 | 15.7 | 17457 | 2026-02-26 15:29:10 | MASTER-Tunka | (02h 46m 22.36s , +08d 15m 50.5s) | C | 10 | 15.1 | 17480 | 2026-02-26 15:29:33 | MASTER-Tunka | (02h 46m 34.99s , +08d 11m 25.9s) | C | 10 | 15.7 | 17480 | 2026-02-26 15:29:33 | MASTER-Tunka | (02h 46m 17.41s , +08d 14m 49.8s) | C | 10 | 15.2 | 17507 | 2026-02-26 15:30:01 | MASTER-Tunka | (02h 46m 40.94s , +08d 11m 33.4s) | C | 10 | 15.7 | 17507 | 2026-02-26 15:30:01 | MASTER-Tunka | (02h 46m 23.14s , +08d 14m 53.9s) | C | 10 | 15.1 | 17531 | 2026-02-26 15:30:24 | MASTER-Tunka | (02h 46m 37.85s , +08d 13m 16.0s) | C | 10 | 15.7 | 17531 | 2026-02-26 15:30:24 | MASTER-Tunka | (02h 46m 20.32s , +08d 16m 41.5s) | C | 10 | 15.0 | 17553 | 2026-02-26 15:30:46 | MASTER-Tunka | (02h 46m 37.93s , +08d 11m 54.6s) | C | 10 | 15.7 | 17553 | 2026-02-26 15:30:46 | MASTER-Tunka | (02h 46m 20.09s , +08d 15m 13.6s) | C | 10 | 15.0 | 17576 | 2026-02-26 15:31:10 | MASTER-Tunka | (02h 46m 40.42s , +08d 12m 54.8s) | C | 10 | 15.6 | 17576 | 2026-02-26 15:31:10 | MASTER-Tunka | (02h 46m 22.84s , +08d 16m 17.8s) | C | 10 | 14.9 | 17600 | 2026-02-26 15:31:33 | MASTER-Tunka | (02h 46m 34.70s , +08d 12m 22.5s) | C | 10 | 15.6 | 17600 | 2026-02-26 15:31:33 | MASTER-Tunka | (02h 46m 16.99s , +08d 15m 44.7s) | C | 10 | 15.1 | 17626 | 2026-02-26 15:32:00 | MASTER-Tunka | (02h 46m 35.77s , +08d 13m 23.5s) | C | 10 | 15.6 | 17626 | 2026-02-26 15:32:00 | MASTER-Tunka | (02h 46m 18.12s , +08d 16m 47.2s) | C | 10 | 15.1 | 17650 | 2026-02-26 15:32:23 | MASTER-Tunka | (02h 46m 40.81s , +08d 12m 21.6s) | C | 10 | 15.7 | 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/43848. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...