TITLE: GCN CIRCULAR NUMBER: 43956 SUBJECT: Fermi GRB 260310B: Global MASTER-Net observations report DATE: 26/03/10 22:30:30 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) started inspect of the Fermi GRB 260310B ( Fermi GBM team, GCN 43955) errorbox 542 sec after notice time and 552 sec after trigger time at 2026-03-10 21:50:36 UT, with upper limit up to 16.9 mag. The observations began at zenith distance = 59 deg. The sun altitude is -50.4 deg. The galactic latitude b = 21 deg., longitude l = 209 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3179876 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 582 | 2026-03-10 21:50:36 | MASTER-Kislovodsk | (07h 54m 35.80s , +13d 00m 23.6s) | C | 60 | 16.6 | 687 | 2026-03-10 21:52:21 | MASTER-Kislovodsk | (07h 58m 19.92s , +14d 56m 29.1s) | C | 60 | 16.9 | 790 | 2026-03-10 21:54:03 | MASTER-Kislovodsk | (07h 46m 02.42s , +14d 53m 53.7s) | C | 60 | 16.8 | 892 | 2026-03-10 21:55:45 | MASTER-Kislovodsk | (07h 51m 26.76s , +11d 07m 39.5s) | C | 60 | 16.5 | 1118 | 2026-03-10 21:59:32 | MASTER-Kislovodsk | (08h 03m 35.41s , +11d 08m 23.4s) | C | 60 | 16.6 | 1219 | 2026-03-10 22:01:12 | MASTER-Kislovodsk | (07h 50m 14.85s , +16d 47m 46.5s) | C | 60 | 16.5 | 1322 | 2026-03-10 22:02:55 | MASTER-Kislovodsk | (08h 02m 41.51s , +16d 48m 06.7s) | C | 60 | 16.7 | 1426 | 2026-03-10 22:04:39 | MASTER-Kislovodsk | (08h 10m 41.96s , +14d 55m 27.7s) | C | 60 | 16.8 | 1527 | 2026-03-10 22:06:20 | MASTER-Kislovodsk | (07h 39m 13.82s , +11d 06m 33.0s) | C | 60 | 16.6 | 1631 | 2026-03-10 22:08:04 | MASTER-Kislovodsk | (07h 48m 50.33s , +09d 12m 03.5s) | C | 60 | 16.5 | 1742 | 2026-03-10 22:09:56 | MASTER-Kislovodsk | (08h 00m 58.87s , +09d 12m 38.7s) | C | 60 | 16.7 | 1849 | 2026-03-10 22:11:42 | MASTER-Kislovodsk | (07h 37m 42.68s , +16d 48m 11.2s) | C | 60 | 16.7 | 1955 | 2026-03-10 22:13:28 | MASTER-Kislovodsk | (07h 33m 33.75s , +14d 52m 48.8s) | C | 60 | 16.5 | 2299 | 2026-03-10 22:19:12 | MASTER-Kislovodsk | (07h 30m 05.05s , +12d 59m 15.0s) | C | 60 | 16.2 | 2407 | 2026-03-10 22:21:00 | MASTER-Kislovodsk | (08h 15m 46.83s , +11d 07m 53.6s) | C | 60 | 16.6 | 2515 | 2026-03-10 22:22:48 | MASTER-Kislovodsk | (08h 15m 18.68s , +16d 48m 43.7s) | C | 60 | 16.4 | 2623 | 2026-03-10 22:24:36 | MASTER-Kislovodsk | (08h 19m 09.07s , +12d 59m 50.9s) | C | 60 | 16.8 | 2720 | 2026-03-10 22:26:13 | MASTER-Kislovodsk | (08h 07m 48.22s , +18d 41m 27.6s) | C | 60 | 16.5 | 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/43956. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...