GCN Circular 43311

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-Kislovodsk robotic telescope  [1]  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the SVOM GRB260103.08 (trigger No 1767405296,10h 29m 22.85s , +78d 07m 01.2s, R=1) errorbox  9 sec after notice time and 47 sec after trigger time at 2026-01-03 01:55:42 UT, with upper limit up to  17.8 mag. The observations began at zenith distance = 36 deg. The sun  altitude  is -29.5 deg. 

The galactic latitude b = 37 deg., longitude l = 131 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=3094431

We obtain a following upper limits.  

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

      52 | 2026-01-03 01:55:42 |   MASTER-Kislovodsk | (10h 28m 21.31s , +78d 15m 14.6s) |   C |    10 | 16.1 |        
      72 | 2026-01-03 01:55:42 |   MASTER-Kislovodsk | (10h 28m 21.31s , +78d 15m 14.7s) |   C |    50 | 17.2 |  Coadd 
      52 | 2026-01-03 01:55:43 |   MASTER-Kislovodsk | (10h 26m 28.30s , +78d 37m 51.0s) |  P| |    10 | 15.1 |        
      88 | 2026-01-03 01:56:13 |   MASTER-Kislovodsk | (10h 28m 20.71s , +78d 15m 17.8s) |   C |    20 | 16.5 |        
      88 | 2026-01-03 01:56:13 |   MASTER-Kislovodsk | (10h 26m 27.38s , +78d 37m 54.9s) |  P| |    20 | 15.8 |        
     129 | 2026-01-03 01:56:54 |   MASTER-Kislovodsk | (10h 28m 20.20s , +78d 15m 20.4s) |   C |    20 | 16.4 |        
     129 | 2026-01-03 01:56:54 |   MASTER-Kislovodsk | (10h 26m 26.58s , +78d 37m 57.6s) |  P| |    20 | 15.7 |        
     174 | 2026-01-03 01:57:35 |   MASTER-Kislovodsk | (10h 28m 19.34s , +78d 15m 23.0s) |   C |    30 | 16.8 |        
     219 | 2026-01-03 01:57:35 |   MASTER-Kislovodsk | (10h 28m 19.30s , +78d 15m 23.2s) |   C |   120 | 17.5 |  Coadd 
     174 | 2026-01-03 01:57:35 |   MASTER-Kislovodsk | (10h 26m 25.67s , +78d 38m 00.3s) |  P| |    30 | 15.9 |        
     229 | 2026-01-03 01:58:25 |   MASTER-Kislovodsk | (10h 28m 18.65s , +78d 15m 25.6s) |   C |    40 | 16.8 |        
     229 | 2026-01-03 01:58:25 |   MASTER-Kislovodsk | (10h 26m 24.60s , +78d 38m 02.7s) |  P| |    40 | 16.1 |        
     295 | 2026-01-03 01:59:25 |   MASTER-Kislovodsk | (10h 28m 17.63s , +78d 15m 28.0s) |   C |    50 | 16.9 |        
     295 | 2026-01-03 01:59:25 |   MASTER-Kislovodsk | (10h 26m 23.54s , +78d 38m 04.8s) |  P| |    50 | 16.2 |        
     375 | 2026-01-03 02:00:35 |   MASTER-Kislovodsk | (10h 28m 16.24s , +78d 15m 30.2s) |   C |    70 | 17.1 |        
     475 | 2026-01-03 02:00:35 |   MASTER-Kislovodsk | (10h 28m 16.19s , +78d 15m 30.3s) |   C |   270 | 17.8 |  Coadd 
     375 | 2026-01-03 02:00:35 |   MASTER-Kislovodsk | (10h 26m 22.26s , +78d 38m 06.6s) |  P| |    70 | 16.4 |        
     475 | 2026-01-03 02:02:05 |   MASTER-Kislovodsk | (10h 28m 14.77s , +78d 15m 32.1s) |   C |    90 | 17.2 |        
     475 | 2026-01-03 02:02:05 |   MASTER-Kislovodsk | (10h 26m 20.59s , +78d 38m 07.9s) |  P| |    90 | 16.6 |        
     596 | 2026-01-03 02:03:56 |   MASTER-Kislovodsk | (10h 28m 13.42s , +78d 15m 32.8s) |   C |   110 | 17.3 |        
     596 | 2026-01-03 02:03:56 |   MASTER-Kislovodsk | (10h 26m 18.31s , +78d 38m 08.2s) |  P| |   110 | 16.4 |        
     731 | 2026-01-03 02:06:07 |   MASTER-Kislovodsk | (10h 28m 13.42s , +78d 15m 32.8s) |   C |   120 | 14.8 |        
     731 | 2026-01-03 02:06:07 |   MASTER-Kislovodsk | (10h 26m 18.35s , +78d 38m 07.2s) |  P| |   120 | 14.4 |        
     908 | 2026-01-03 02:09:34 |   MASTER-Kislovodsk | (10h 34m 57.99s , +79d 17m 59.5s) |   C |    60 | 17.0 |        
     908 | 2026-01-03 02:09:34 |   MASTER-Kislovodsk | (10h 09m 58.98s , +79d 35m 40.7s) |   C |    60 | 17.2 |        
    1008 | 2026-01-03 02:11:13 |   MASTER-Kislovodsk | (10h 50m 24.38s , +77d 23m 12.9s) |   C |    60 | 17.0 |        
    1008 | 2026-01-03 02:11:13 |   MASTER-Kislovodsk | (10h 29m 13.06s , +77d 41m 41.3s) |   C |    60 | 17.3 |        
    1113 | 2026-01-03 02:12:58 |   MASTER-Kislovodsk | (10h 29m 26.49s , +78d 16m 54.1s) |   C |    60 | 17.0 |        
    1113 | 2026-01-03 02:12:58 |   MASTER-Kislovodsk | (10h 06m 36.99s , +78d 34m 43.4s) |   C |    60 | 17.2 |        
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