TITLE: GCN CIRCULAR NUMBER: 43648 SUBJECT: LAT GRB260208.41: Global MASTER-Net observations report DATE: 26/02/08 16:44:32 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 GRB260208.41 (trigger No 792237169,06h 38m 33.12s , -13d 50m 16.8s, R=0.0598333) errorbox 6014 sec after notice time and 24109 sec after trigger time at 2026-02-08 16:34:34 UT, with upper limit up to 16.4 mag. The observations began at zenith distance = 70 deg. The sun altitude is -52.8 deg. The galactic latitude b = -9 deg., longitude l = 224 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3126408 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 24140 | 2026-02-08 16:34:34 | MASTER-Tunka | (06h 37m 00.05s , -13d 24m 07.8s) | C | 60 | 15.9 | 24212 | 2026-02-08 16:35:47 | MASTER-Tunka | (06h 36m 53.46s , -13d 23m 06.3s) | C | 60 | 15.9 | 24284 | 2026-02-08 16:36:59 | MASTER-Tunka | (06h 36m 52.89s , -13d 21m 12.6s) | C | 60 | 16.4 | 24358 | 2026-02-08 16:38:12 | MASTER-Tunka | (06h 36m 59.13s , -13d 21m 17.5s) | C | 60 | 16.4 | 24431 | 2026-02-08 16:39:25 | MASTER-Tunka | (06h 36m 53.87s , -13d 21m 24.3s) | C | 60 | 16.4 | 24505 | 2026-02-08 16:40:40 | MASTER-Tunka | (06h 37m 00.18s , -13d 21m 29.5s) | C | 60 | 16.0 | 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/43648. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...