TITLE:   GCN CIRCULAR
NUMBER:  36003
SUBJECT: Integral GRB240401.69: Global MASTER-Net observations report
DATE:    24/04/01 17:19:26 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

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-Tavrida robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Integral GRB240401.69 (trigger No 10651,05h 34m 06.25s , +22d 00m 11.5s, R=0.0546667) errorbox  946 sec after notice time and 961 sec after trigger time at 2024-04-01 16:54:58 UT, with upper limit up to  16.4 mag. Observations started at twilight.  The observations began at zenith distance = 36 deg. The sun  altitude  is -8.8 deg. 

The galactic latitude b = -5 deg., longitude l = 185 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2411905

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

    1051 |      MASTER-Tavrida |   C |   180 | 14.9 |        
    1241 |      MASTER-Tavrida |   C |   180 | 15.3 |        
    1428 |      MASTER-Tavrida |   C |   180 | 15.7 |        
    1615 |      MASTER-Tavrida |   C |   180 | 15.9 |        
    1802 |      MASTER-Tavrida |   C |   180 | 16.2 |        
    1991 |      MASTER-Tavrida |   C |   180 | 16.4 |        
Filter C is a clear (unfiltred) band. 


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