TITLE: GCN CIRCULAR NUMBER: 45648 SUBJECT: EP Alert 260919.40: Global MASTER-Net observations report DATE: 26/09/19 19:37:10 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs 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 (Lomonosov MSU) D.Buckley (SAAO), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity) A.Sosnovskij (Lomonosov MSU) A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory) L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory) R.Rebolo (The Instituto de Astrofisica de Canarias) O.Gress, N.Budnev(ISU) M. Segura, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA) MASTER-Tavrida robotic telescope [1] located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the EP Alert 260919.40 (trigger No 1709318491,02h 00m 10.08s , -08d 39m 25.2s, R=0.0513526) errorbox 35625 sec after notice time and 36068 sec after trigger time at 2026-09-19 19:30:47 UT, with upper limit up to 17.7 mag. The observations began at zenith distance = 79 deg. The sun altitude is -36.1 deg. The galactic latitude b = -65 deg., longitude l = 168 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3507102 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 36099 | 2026-09-19 19:30:47 | MASTER-Tavrida | (02h 00m 07.97s , -08d 39m 15.8s) | C | 60 | 17.7 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. [1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp. http : // www.pereplet.ru/lipunov/625.html