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GCN Circular 40905

Subject

Fermi GRB 250702E: Global MASTER-Net observations report

Event

GRB 250702E

Date

2025-07-03T02:15:35Z (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-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) started inspect of the Fermi GRB 250702E ( Fermi GBM team, GCN 40890Loading...
 
 ) errorbox  28126 sec after notice time and 28161 sec after trigger time at 2025-07-03 00:10:54 UT, with upper limit up to  18.6 mag. The observations began at zenith distance = 28 deg. The sun  altitude  is -68.5 deg. 

The galactic latitude b = -12 deg., longitude l = 19 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2923298

We obtain a following upper limits.  

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

   28191 | 2025-07-03 00:10:54 |         MASTER-SAAO | (18h 58m 11.78s , -10d 24m 39.1s) |   C |    60 | 18.2 |        
   28289 | 2025-07-03 00:12:31 |         MASTER-SAAO | (19h 06m 18.96s , -10d 26m 55.8s) |   C |    60 | 18.6 |        
Filter C is a clear (unfiltred) band. 


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