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GCN Circular 40673

Subject
EP250610a: Global MASTER-Net observations report
Date
2025-06-10T19:36:20Z (3 days 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-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 EP250610a ( EP Team et al., GCN 40660Loading...
 
 ) errorbox  972 sec after notice time and 9094 sec after trigger time at 2025-06-10 06:57:24 UT, with upper limit up to  17.6 mag. The observations began at zenith distance = 82 deg. The sun  altitude  is -57.2 deg. 

MASTER-Kislovodsk robotic telescope  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the EP250610a errorbox  44872 sec after notice time and 52993 sec after trigger time at 2025-06-10 19:09:03 UT, with upper limit up to  17.4 mag. The observations began at zenith distance = 15 deg. The sun  altitude  is -18.3 deg. 

The galactic latitude b = 42 deg., longitude l = 61 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2898181

We obtain a following upper limits.  

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

    9229 | 2025-06-10 06:57:24 |         MASTER-OAFA | (16h 33m 32.66s , +38d 48m 08.6s) |   C |   270 | 17.6 |  Coadd 
   53024 | 2025-06-10 19:09:03 |   MASTER-Kislovodsk | (16h 31m 32.68s , +38d 50m 44.6s) |   C |    60 | 17.0 |        
   53210 | 2025-06-10 19:12:09 |   MASTER-Kislovodsk | (16h 31m 34.53s , +38d 48m 49.2s) |   C |    60 | 17.4 |        
   53547 | 2025-06-10 19:17:46 |   MASTER-Kislovodsk | (16h 31m 41.01s , +38d 50m 51.7s) |   C |    60 | 17.1 |        
   53720 | 2025-06-10 19:20:40 |   MASTER-Kislovodsk | (16h 31m 35.46s , +38d 50m 56.6s) |   C |    60 | 16.0 |        
   53893 | 2025-06-10 19:23:32 |   MASTER-Kislovodsk | (16h 31m 32.13s , +38d 48m 59.5s) |   C |    60 | 17.0 |        
Filter C is a clear (unfiltred) band. 


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