TITLE:   GCN CIRCULAR
NUMBER:  35970
SUBJECT: Fermi  trigger No 732657380: Global MASTER-Net observations report
DATE:    24/03/21 15:45:44 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-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB240320.83 (trigger No 732657380,18h 20m 40.80s , -34d 13m 12.0s, R=3.14) errorbox 9088 sec after trigger time at 2024-03-20 22:27:43 UT, with upper limit up to  17.0 mag. The observations began at zenith distance = 78 deg. The sun  altitude  is -57.9 deg. 

The galactic latitude b = -10 deg., longitude l = 359 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2403918

We obtain a following upper limits.  

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

    9119 | 2024-03-20 22:27:43 |         MASTER-SAAO | (18h 28m 13.21s , -38d 52m 59.6s) |   C |    60 | 16.6 |        
    9119 | 2024-03-20 22:27:43 |         MASTER-SAAO | (18h 25m 58.91s , -38d 40m 19.5s) |   C |    60 | 17.0 |        
    9199 | 2024-03-20 22:29:03 |         MASTER-SAAO | (18h 19m 02.96s , -37d 00m 13.3s) |   C |    60 | 16.3 |        
Filter C is a clear (unfiltred) band. 


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