TITLE:   GCN CIRCULAR
NUMBER:  36294
SUBJECT: Fermi  trigger No 735697285: Global MASTER-Net observations report
DATE:    24/04/25 00:31:14 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) started inspect of the Fermi GRB240425.01 (trigger No 735697285,15h 01m 45.60s , +45d 39m 00.0s, R=5.8) errorbox  96 sec after notice time and 128 sec after trigger time at 2024-04-25 00:23:28 UT, with upper limit up to  13.0 mag. The observations began at zenith distance = 20 deg. The sun  altitude  is -21.9 deg. 

MASTER-SAAO robotic telescope  located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB240425.01 errorbox  109 sec after notice time and 141 sec after trigger time at 2024-04-25 00:23:41 UT, with upper limit up to  17.1 mag. The observations began at zenith distance = 79 deg. The sun  altitude  is -59.1 deg. 

The galactic latitude b = 58 deg., longitude l = 77 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2434813

We obtain a following upper limits.  

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

     144 | 2024-04-25 00:23:28 |      MASTER-Tavrida | (15h 02m 27.12s , +45d 55m 23.3s) |   C |    30 | 13.0 |        
     156 | 2024-04-25 00:23:41 |         MASTER-SAAO | (15h 00m 05.69s , +45d 46m 57.7s) |   C |    30 | 17.1 |        
     156 | 2024-04-25 00:23:41 |         MASTER-SAAO | (15h 02m 38.82s , +45d 34m 01.6s) |   C |    30 | 17.0 |        
     181 | 2024-04-25 00:24:05 |      MASTER-Tavrida | (15h 02m 29.03s , +45d 57m 04.9s) |   C |    30 | 12.4 |        
     206 | 2024-04-25 00:24:31 |         MASTER-SAAO | (15h 00m 05.85s , +45d 47m 01.8s) |   C |    30 | 17.1 |        
     206 | 2024-04-25 00:24:31 |         MASTER-SAAO | (15h 02m 38.88s , +45d 34m 06.6s) |   C |    30 | 17.0 |        
Filter C is a clear (unfiltred) band. 


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