TITLE: GCN CIRCULAR NUMBER: 40286 SUBJECT: Fermi trigger No 767623859: Global MASTER-Net observations report DATE: 25/04/30 09:31:00 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 GRB250429.54 (trigger No 767623859,22h 03m 43.92s , -05d 28m 01.2s, R=31.13) errorbox 73850 sec after notice time and 73884 sec after trigger time at 2025-04-30 09:22:19 UT, with upper limit up to 19.5 mag. The observations began at zenith distance = 42 deg. The sun altitude is -22.3 deg. The galactic latitude b = -45 deg., longitude l = 55 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2856527 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 73905 | 2025-04-30 09:22:19 | MASTER-OAFA | (21h 58m 38.65s , -10d 46m 32.6s) | C | 40 | 17.6 | 73915 | 2025-04-30 09:22:19 | MASTER-OAFA | (22h 07m 54.27s , -10d 23m 06.7s) | C | 60 | 19.2 | 73983 | 2025-04-30 09:23:37 | MASTER-OAFA | (22h 01m 48.50s , -14d 36m 44.5s) | C | 40 | 17.8 | 73993 | 2025-04-30 09:23:37 | MASTER-OAFA | (22h 11m 12.61s , -14d 13m 10.4s) | C | 60 | 19.5 | 74058 | 2025-04-30 09:24:53 | MASTER-OAFA | (22h 13m 36.90s , -16d 29m 55.1s) | C | 40 | 18.0 | 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/40286. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...