GCN Circular 35466

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tunka robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB240102.13 (trigger No 725857207,12h 04m 45.60s , -16d 33m 36.0s, R=1.99) errorbox  29555 sec after notice time and 72382 sec after trigger time at 2024-01-02 23:06:24 UT, with upper limit up to  14.2 mag. The observations began at zenith distance = 71 deg. The sun  altitude  is -18.3 deg. 

The galactic latitude b = 45 deg., longitude l = 288 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2348394

We obtain a following upper limits.  

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

   72390 | 2024-01-02 23:06:24 |        MASTER-Tunka | (12h 08m 29.91s , -19d 22m 13.7s) |   C |    15 | 14.1 |        
   72417 | 2024-01-02 23:06:51 |        MASTER-Tunka | (12h 07m 49.80s , -17d 29m 14.6s) |   C |    15 | 14.2 |        
   72445 | 2024-01-02 23:07:21 |        MASTER-Tunka | (12h 16m 18.51s , -17d 29m 19.9s) |   C |    10 | 14.1 |        
   72483 | 2024-01-02 23:08:02 |        MASTER-Tunka | (11h 53m 08.38s , -15d 34m 47.7s) |   C |     5 | 13.7 |        
   72503 | 2024-01-02 23:08:22 |        MASTER-Tunka | (12h 00m 39.66s , -15d 33m 13.3s) |   C |     5 | 13.7 |        
Filter C is a clear (unfiltred) band. 


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