TITLE:   GCN CIRCULAR
NUMBER:  40432
SUBJECT: EP250511a: Global MASTER-Net observations report
DATE:    25/05/11 20:36:40 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

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 EP250511a ( EP Team et al., GCN 40429) errorbox  28887 sec after notice time and 44100 sec after trigger time at 2025-05-11 20:14:59 UT, with upper limit up to  16.9 mag. The observations began at zenith distance = 30 deg. The sun  altitude  is -55.6 deg. 

The galactic latitude b = 58 deg., longitude l = 322 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2867812

We obtain a following upper limits.  

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

   44115 | 2025-05-11 20:14:59 |         MASTER-SAAO | (13h 27m 09.60s , -02d 50m 52.7s) |   C |    30 | 16.8 |        
   44220 | 2025-05-11 20:14:59 |         MASTER-SAAO | (13h 27m 09.60s , -02d 50m 52.5s) |   C |   240 | 16.8 |  Coadd 
   44165 | 2025-05-11 20:15:48 |         MASTER-SAAO | (13h 27m 07.01s , -02d 49m 12.4s) |   C |    30 | 16.9 |        
   44259 | 2025-05-11 20:16:38 |         MASTER-SAAO | (13h 27m 08.05s , -02d 50m 48.6s) |   C |   120 | 16.7 |        
   44399 | 2025-05-11 20:18:57 |         MASTER-SAAO | (13h 27m 12.36s , -02d 49m 05.6s) |   C |   120 | 16.8 |        
   44538 | 2025-05-11 20:21:16 |         MASTER-SAAO | (13h 27m 08.49s , -02d 49m 44.1s) |   C |   120 | 16.6 |        
   44707 | 2025-05-11 20:23:36 |         MASTER-SAAO | (13h 27m 08.91s , -02d 48m 40.9s) |   C |   180 | 15.3 |        
   44907 | 2025-05-11 20:26:55 |         MASTER-SAAO | (13h 27m 18.75s , -02d 49m 37.8s) |   C |   180 | 16.1 |        
Filter C is a clear (unfiltred) band. 


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