TITLE:   GCN CIRCULAR
NUMBER:  35774
SUBJECT: Fermi GRB 240222A: Global MASTER-Net observations report
DATE:    24/02/22 18:31:17 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 GRB 240222A ( Fermi GBM team, GCN 35769) errorbox  33348 sec after notice time and 33382 sec after trigger time at 2024-02-22 18:07:54 UT, with upper limit up to  18.3 mag. Observations started at twilight.  The observations began at zenith distance = 50 deg. The sun  altitude  is -10.1 deg. 

The galactic latitude b = -6 deg., longitude l = 281 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2383850

We obtain a following upper limits.  

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

   33473 | 2024-02-22 18:07:54 |         MASTER-SAAO | (09h 40m 49.96s , -68d 03m 28.5s) |   C |   180 | 17.9 |        
   33473 | 2024-02-22 18:07:54 |         MASTER-SAAO | (09h 18m 15.91s , -67d 52m 27.6s) |   C |   180 | 17.4 |        
   33672 | 2024-02-22 18:11:13 |         MASTER-SAAO | (09h 40m 56.74s , -68d 04m 32.3s) |   C |   180 | 18.3 |        
Filter C is a clear (unfiltred) band. 


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