TITLE: GCN CIRCULAR NUMBER: 41791 SUBJECT: Fermi GRB 250910B: Global MASTER-Net observations report DATE: 25/09/11 10:31:00 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-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 250910B ( Fermi GBM team, GCN 41778) errorbox 45057 sec after notice time and 45097 sec after trigger time at 2025-09-11 07:23:42 UT, with upper limit up to 19.9 mag. The observations began at zenith distance = 40 deg. The sun altitude is -41.7 deg. The galactic latitude b = -34 deg., longitude l = 252 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2989479 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 45128 | 2025-09-11 07:23:42 | MASTER-OAFA | (05h 21m 01.46s , -46d 16m 04.7s) | C | 60 | 19.9 | 45203 | 2025-09-11 07:24:58 | MASTER-OAFA | (05h 21m 06.25s , -46d 17m 02.2s) | C | 60 | 19.8 | 45277 | 2025-09-11 07:26:12 | MASTER-OAFA | (05h 21m 01.18s , -46d 17m 59.3s) | C | 60 | 19.9 | 45353 | 2025-09-11 07:27:28 | MASTER-OAFA | (05h 21m 05.78s , -46d 17m 54.0s) | C | 60 | 19.9 | 45428 | 2025-09-11 07:28:43 | MASTER-OAFA | (05h 21m 03.82s , -46d 16m 02.0s) | C | 60 | 19.8 | 45503 | 2025-09-11 07:29:58 | MASTER-OAFA | (05h 21m 03.84s , -46d 17m 30.1s) | C | 60 | 19.8 | 45579 | 2025-09-11 07:31:13 | MASTER-OAFA | (05h 21m 06.46s , -46d 16m 12.8s) | C | 60 | 19.8 | 45656 | 2025-09-11 07:32:31 | MASTER-OAFA | (05h 21m 00.95s , -46d 16m 45.4s) | C | 60 | 19.8 | 45734 | 2025-09-11 07:33:49 | MASTER-OAFA | (05h 21m 01.87s , -46d 15m 42.5s) | C | 60 | 19.8 | 45811 | 2025-09-11 07:35:06 | MASTER-OAFA | (05h 21m 07.33s , -46d 16m 40.1s) | C | 60 | 19.9 | 45888 | 2025-09-11 07:36:22 | MASTER-OAFA | (05h 21m 00.65s , -46d 17m 37.5s) | C | 60 | 19.8 | 45962 | 2025-09-11 07:37:36 | MASTER-OAFA | (05h 21m 07.79s , -46d 17m 14.3s) | C | 60 | 19.9 | 46036 | 2025-09-11 07:38:51 | MASTER-OAFA | (05h 21m 04.04s , -46d 15m 34.4s) | C | 60 | 19.9 | 46112 | 2025-09-11 07:40:06 | MASTER-OAFA | (05h 21m 04.05s , -46d 17m 27.2s) | C | 60 | 19.9 | 46187 | 2025-09-11 07:41:21 | MASTER-OAFA | (05h 21m 07.22s , -46d 15m 29.4s) | C | 60 | 19.9 | 46263 | 2025-09-11 07:42:38 | MASTER-OAFA | (05h 21m 00.93s , -46d 16m 25.0s) | C | 60 | 19.9 | 46340 | 2025-09-11 07:43:55 | MASTER-OAFA | (05h 21m 00.54s , -46d 15m 22.3s) | C | 60 | 19.9 | 46417 | 2025-09-11 07:45:11 | MASTER-OAFA | (05h 21m 06.25s , -46d 16m 20.5s) | C | 60 | 19.8 | 46495 | 2025-09-11 07:46:29 | MASTER-OAFA | (05h 21m 01.68s , -46d 17m 18.0s) | C | 60 | 19.9 | 46569 | 2025-09-11 07:47:43 | MASTER-OAFA | (05h 21m 06.17s , -46d 16m 51.8s) | C | 60 | 19.9 | 46645 | 2025-09-11 07:49:00 | MASTER-OAFA | (05h 21m 04.24s , -46d 15m 24.7s) | C | 60 | 19.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/41791. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...