TITLE: GCN CIRCULAR NUMBER: 40832 SUBJECT: Swift GRB 250625A: Global MASTER-Net observations report DATE: 25/06/26 02:24:25 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-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB 250625A ( M. Ferro et al., GCN 40825) errorbox 16240 sec after notice time and 16278 sec after trigger time at 2025-06-25 20:36:14 UT, with upper limit up to 14.7 mag. The observations began at zenith distance = 22 deg. The sun altitude is -20.8 deg. MASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB 250625A errorbox 35307 sec after notice time and 35345 sec after trigger time at 2025-06-26 01:54:01 UT, with upper limit up to 18.9 mag. The observations began at zenith distance = 60 deg. The sun altitude is -53.1 deg. The galactic latitude b = 28 deg., longitude l = 45 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2916460 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 16368 | MASTER-Tavrida | C | 180 | 14.7 | 35435 | MASTER-OAFA | C | 180 | 18.5 | 35630 | MASTER-OAFA | C | 180 | 18.2 | 35825 | MASTER-OAFA | C | 180 | 18.9 | 36026 | MASTER-OAFA | C | 180 | 18.6 | 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/40832. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...