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GCN Circular 40714

Subject
EP250612a: Global MASTER-Net observations report
Date
2025-06-12T22:36:21Z (a day ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
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-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) was pointed to the EP250612a ( EP Team et al., GCN 40700Loading...
 
 ) errorbox  33238 sec after notice time and 35413 sec after trigger time at 2025-06-12 22:18:18 UT, with upper limit up to  18.9 mag. The observations began at zenith distance = 24 deg. The sun  altitude  is -80.1 deg. 

The galactic latitude b = 25 deg., longitude l = 340 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2901165

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

   35444 | 2025-06-12 22:18:18 |         MASTER-SAAO | (15h 17m 45.90s , -26d 51m 07.4s) |   C |    60 | 18.5 |        
   35444 | 2025-06-12 22:18:18 |         MASTER-SAAO | (15h 15m 46.32s , -26d 35m 46.7s) |   C |    60 | 18.8 |        
   35635 | 2025-06-12 22:21:29 |         MASTER-SAAO | (15h 17m 42.75s , -26d 50m 04.0s) |   C |    60 | 18.6 |        
   35635 | 2025-06-12 22:21:29 |         MASTER-SAAO | (15h 15m 43.63s , -26d 34m 41.7s) |   C |    60 | 18.9 |        
   35828 | 2025-06-12 22:24:42 |         MASTER-SAAO | (15h 17m 49.62s , -26d 49m 56.6s) |   C |    60 | 18.6 |        
   35828 | 2025-06-12 22:24:42 |         MASTER-SAAO | (15h 15m 50.50s , -26d 34m 33.7s) |   C |    60 | 18.8 |        
   36019 | 2025-06-12 22:27:53 |         MASTER-SAAO | (15h 17m 48.24s , -26d 50m 30.1s) |   C |    60 | 18.6 |        
   36019 | 2025-06-12 22:27:53 |         MASTER-SAAO | (15h 15m 49.05s , -26d 35m 06.7s) |   C |    60 | 18.8 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.