GCN Circular 45481

Subject
EP260830a: Global MASTER-Net observations report
Event
EP260830a
Date
2026-09-01T06:36:34Z (2 days ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
M. Segura,  F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA)

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 (CrAO RAS)

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)


MASTER-OAFA robotic telescope  [1]  located in Argentina (OAFA observatory of San Juan National University) was pointed to the EP260830a ( EP Team at NAOC/CAS <ep_ta@bao.ac.cn> et al., GCN 45480Loading...
 
 ) errorbox  245 sec after notice time and 1 days 53772 sec after trigger time at 2026-09-01 06:26:35 UT, with upper limit up to  18.6 mag. The observations began at zenith distance = 49 deg. The sun  altitude  is -55.3 deg. 

The galactic latitude b = -45 deg., longitude l = 109 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=3497638

We obtain a following upper limits.  

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

  140203 | 2026-09-01 06:26:35 |         MASTER-OAFA | (00h 07m 26.40s , +16d 48m 31.6s) |   C |    60 | 18.5 |        
  140280 | 2026-09-01 06:27:53 |         MASTER-OAFA | (00h 07m 25.14s , +16d 49m 34.6s) |   C |    60 | 18.6 |        
  140357 | 2026-09-01 06:29:09 |         MASTER-OAFA | (00h 07m 32.14s , +16d 48m 37.1s) |   C |    60 | 18.5 |        
  140434 | 2026-09-01 06:30:27 |         MASTER-OAFA | (00h 07m 26.13s , +16d 47m 39.6s) |   C |    60 | 18.6 |        
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