TITLE: GCN CIRCULAR NUMBER: 41612 SUBJECT: EP250830a: Global MASTER-Net observations report DATE: 25/08/30 14:27:21 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-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) was pointed to the EP250830a ( EP Team et al., GCN 41611) errorbox 9623 sec after trigger time at 2025-08-30 06:37:32 UT, with upper limit up to 20.1 mag. The observations began at zenith distance = 65 deg. The sun altitude is -54.1 deg. The galactic latitude b = -23 deg., longitude l = 275 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2980099 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 9644 | 2025-08-30 06:37:32 | MASTER-OAFA | (07h 03m 18.97s , -64d 47m 00.0s) | C | 40 | 19.3 | 9684 | 2025-08-30 06:37:32 | MASTER-OAFA | (07h 03m 18.97s , -64d 46m 60.0s) | C | 120 | 20.1 | Coadd 9690 | 2025-08-30 06:38:18 | MASTER-OAFA | (07h 03m 18.83s , -64d 46m 58.5s) | C | 40 | 19.3 | 9735 | 2025-08-30 06:39:04 | MASTER-OAFA | (07h 03m 18.65s , -64d 46m 56.6s) | C | 40 | 19.3 | 9781 | 2025-08-30 06:39:50 | MASTER-OAFA | (07h 03m 18.51s , -64d 46m 55.0s) | C | 40 | 19.3 | 9821 | 2025-08-30 06:39:50 | MASTER-OAFA | (07h 03m 18.52s , -64d 46m 54.9s) | C | 120 | 20.1 | Coadd 9827 | 2025-08-30 06:40:35 | MASTER-OAFA | (07h 03m 18.38s , -64d 46m 53.5s) | C | 40 | 19.3 | 9872 | 2025-08-30 06:41:21 | MASTER-OAFA | (07h 03m 18.20s , -64d 46m 52.4s) | C | 40 | 19.3 | 9918 | 2025-08-30 06:42:07 | MASTER-OAFA | (07h 03m 18.10s , -64d 46m 51.1s) | C | 40 | 19.4 | 9964 | 2025-08-30 06:42:52 | MASTER-OAFA | (07h 03m 17.96s , -64d 46m 49.8s) | C | 40 | 19.4 | 10010 | 2025-08-30 06:43:38 | MASTER-OAFA | (07h 03m 17.75s , -64d 46m 48.2s) | C | 40 | 19.3 | 10056 | 2025-08-30 06:44:24 | MASTER-OAFA | (07h 03m 17.57s , -64d 46m 46.8s) | C | 40 | 19.3 | 10101 | 2025-08-30 06:45:10 | MASTER-OAFA | (07h 03m 17.44s , -64d 46m 45.6s) | C | 40 | 16.0 | 10147 | 2025-08-30 06:45:56 | MASTER-OAFA | (07h 03m 17.20s , -64d 46m 44.0s) | C | 40 | 19.1 | 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/41612. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...