TITLE:   GCN CIRCULAR
NUMBER:  37393
SUBJECT: Fermi GRB 240905B: Global MASTER-Net observations report
DATE:    24/09/05 11:30:40 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-Amur robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 240905B ( Fermi GBM team, GCN 37389) errorbox  23620 sec after notice time and 23653 sec after trigger time at 2024-09-05 11:01:29 UT, with upper limit up to  16.2 mag. Observations started at twilight.  The observations began at zenith distance = 35 deg. The sun  altitude  is -9.3 deg. 

The galactic latitude b = 22 deg., longitude l = 41 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2589953

We obtain a following upper limits.  

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

   23684 | 2024-09-05 11:01:29 |         MASTER-Amur | (17h 37m 46.69s , +16d 24m 43.3s) |   C |    60 | 16.2 |        
   23763 | 2024-09-05 11:02:49 |         MASTER-Amur | (17h 46m 01.25s , +16d 24m 00.3s) |   C |    60 | 16.1 |        
   23865 | 2024-09-05 11:04:31 |         MASTER-Amur | (17h 48m 50.82s , +18d 19m 37.2s) |   C |    60 | 15.8 |        
Filter C is a clear (unfiltred) band. 


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