GCN Circular 35663

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) was pointed to the IceCube Alert 240204.38 (trigger No 62272876,23h 14m 35.52s , +11d 03m 32.4s, R=0.51) errorbox  6920 sec after notice time and 6988 sec after trigger time at 2024-02-04 11:05:28 UT, with upper limit up to  18.9 mag. Observations started at twilight.  The observations began at zenith distance = 60 deg. The sun  altitude  is -10.4 deg. 

The galactic latitude b = -45 deg., longitude l = 89 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2371099

We obtain a following upper limits.  

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

    7018 | 2024-02-04 11:05:28 |        MASTER-Tunka | (23h 14m 28.24s , +11d 09m 19.8s) |   C |    60 | 16.2 |  Coadd 
    7321 | 2024-02-04 11:10:31 |        MASTER-Tunka | (23h 08m 00.78s , +10d 47m 13.2s) |   C |    60 | 14.4 |  Coadd 
    7709 | 2024-02-04 11:16:59 |        MASTER-Tunka | (23h 16m 05.80s , +10d 48m 14.4s) |   C |    60 | 14.7 |  Coadd 
    8468 | 2024-02-04 11:29:38 |        MASTER-Tunka | (23h 14m 28.13s , +11d 09m 38.0s) |   C |    60 | 14.6 |  Coadd 
    8843 | 2024-02-04 11:35:53 |        MASTER-Tunka | (23h 07m 54.64s , +10d 47m 24.9s) |   C |    60 | 14.1 |  Coadd 
    9217 | 2024-02-04 11:42:07 |        MASTER-Tunka | (23h 16m 02.60s , +10d 48m 22.4s) |   C |    60 | 14.7 |  Coadd 
    9470 | 2024-02-04 11:46:20 |        MASTER-Tunka | (23h 14m 20.74s , +11d 07m 47.7s) |   C |    60 | 17.9 |  Coadd 
    9536 | 2024-02-04 11:47:25 |        MASTER-Tunka | (23h 07m 58.87s , +10d 46m 11.9s) |   C |    60 | 17.8 |  Coadd 
    9893 | 2024-02-04 11:53:23 |        MASTER-Tunka | (23h 16m 01.82s , +10d 46m 04.6s) |   C |    60 | 18.9 |        
Filter C is a clear (unfiltred) band. 


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