GCN Circular 44150

Subject
EP260329b: Global MASTER-Net observations report
Event
EP260329b
Date
2026-03-29T23:45:30Z (11 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  [1]  located in Argentina (OAFA observatory of San Juan National University) was pointed to the EP260329b ( EP Team et al., GCN 44142Loading...
 
 ) errorbox  41172 sec after notice time and 46747 sec after trigger time at 2026-03-29 23:35:07 UT, with upper limit up to  17.2 mag. Observations started at twilight.  The observations began at zenith distance = 75 deg. The sun  altitude  is -13.8 deg. 

The galactic latitude b = 65 deg., longitude l = 277 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=3219325

We obtain a following upper limits.  

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

   46777 | 2026-03-29 23:35:07 |         MASTER-OAFA | (12h 05m 25.47s , +04d 20m 43.8s) |   C |    60 | 16.4 |        
   46837 | 2026-03-29 23:35:07 |         MASTER-OAFA | (12h 05m 25.47s , +04d 20m 43.7s) |   C |   180 | 17.2 |  Coadd 
   46852 | 2026-03-29 23:36:21 |         MASTER-OAFA | (12h 05m 25.71s , +04d 21m 49.7s) |   C |    60 | 16.6 |        
   46927 | 2026-03-29 23:37:36 |         MASTER-OAFA | (12h 05m 33.10s , +04d 20m 55.0s) |   C |    60 | 16.7 |        
   47124 | 2026-03-29 23:40:54 |         MASTER-OAFA | (12h 05m 30.36s , +04d 21m 51.8s) |   C |    60 | 16.9 |        
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