TITLE: GCN CIRCULAR NUMBER: 41588 SUBJECT: EP250828a: Global MASTER-Net observations report DATE: 25/08/29 08:54:21 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 EP250828a ( EP Team et al., GCN 41574) errorbox 75567 sec after notice time and 1 days 1111 sec after trigger time at 2025-08-29 07:51:04 UT, with upper limit up to 18.8 mag. The observations began at zenith distance = 76 deg. The sun altitude is -39.8 deg. The galactic latitude b = -26 deg., longitude l = 76 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2978651 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 87541 | 2025-08-29 07:51:04 | MASTER-OAFA | (21h 51m 57.17s , +20d 28m 10.2s) | C | 60 | 18.8 | 87618 | 2025-08-29 07:52:21 | MASTER-OAFA | (21h 52m 02.14s , +20d 27m 10.6s) | C | 60 | 18.6 | 87694 | 2025-08-29 07:53:37 | MASTER-OAFA | (21h 51m 56.69s , +20d 26m 10.1s) | C | 60 | 18.6 | 87771 | 2025-08-29 07:54:54 | MASTER-OAFA | (21h 52m 01.95s , +20d 26m 11.4s) | C | 60 | 18.6 | 87831 | 2025-08-29 07:54:54 | MASTER-OAFA | (21h 52m 02.01s , +20d 26m 11.0s) | C | 180 | 18.5 | Coadd 87844 | 2025-08-29 07:56:07 | MASTER-OAFA | (21h 50m 57.78s , +20d 27m 39.7s) | C | 60 | 18.5 | 87918 | 2025-08-29 07:57:20 | MASTER-OAFA | (21h 50m 57.71s , +20d 27m 39.6s) | C | 60 | 18.5 | 87991 | 2025-08-29 07:58:34 | MASTER-OAFA | (21h 50m 57.62s , +20d 27m 39.5s) | C | 60 | 18.5 | 88064 | 2025-08-29 07:59:46 | MASTER-OAFA | (21h 50m 57.50s , +20d 27m 39.7s) | C | 60 | 18.4 | 88137 | 2025-08-29 08:00:59 | MASTER-OAFA | (21h 50m 57.38s , +20d 27m 40.1s) | C | 60 | 18.3 | 88723 | 2025-08-29 08:10:46 | MASTER-OAFA | (21h 52m 01.43s , +20d 26m 02.4s) | C | 60 | 17.4 | 88801 | 2025-08-29 08:12:04 | MASTER-OAFA | (21h 51m 59.20s , +20d 27m 52.2s) | C | 60 | 17.3 | 88879 | 2025-08-29 08:13:22 | MASTER-OAFA | (21h 51m 59.14s , +20d 26m 02.3s) | C | 60 | 17.3 | 88939 | 2025-08-29 08:13:22 | MASTER-OAFA | (21h 51m 59.16s , +20d 26m 02.1s) | C | 180 | 17.4 | Coadd 88954 | 2025-08-29 08:14:36 | MASTER-OAFA | (21h 52m 02.29s , +20d 27m 53.3s) | C | 60 | 17.0 | 89030 | 2025-08-29 08:15:53 | MASTER-OAFA | (21h 51m 56.83s , +20d 26m 54.8s) | C | 60 | 16.6 | 89107 | 2025-08-29 08:17:09 | MASTER-OAFA | (21h 51m 55.72s , +20d 27m 52.7s) | C | 60 | 16.0 | 89182 | 2025-08-29 08:18:25 | MASTER-OAFA | (21h 52m 01.38s , +20d 26m 50.8s) | C | 60 | 15.7 | 89256 | 2025-08-29 08:19:38 | MASTER-OAFA | (21h 51m 55.58s , +20d 25m 48.1s) | C | 60 | 15.1 | 89331 | 2025-08-29 08:20:53 | MASTER-OAFA | (21h 52m 01.76s , +20d 26m 13.7s) | C | 60 | 13.9 | 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/41588. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...