GCN Circular 35735

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 GRB240215.83 (trigger No 729719508,19h 32m 16.08s , -19d 58m 58.8s, R=15.48) errorbox  18211 sec after notice time and 18776 sec after trigger time at 2024-02-16 01:04:40 UT, with upper limit up to  17.1 mag. The observations began at zenith distance = 79 deg. The sun  altitude  is -35.3 deg. 

The galactic latitude b = -18 deg., longitude l = 19 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2379323

We obtain a following upper limits.  

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

   18806 | 2024-02-16 01:04:40 |         MASTER-SAAO | (18h 29m 54.08s , -29d 10m 00.4s) |   C |    60 | 17.1 |        
   18806 | 2024-02-16 01:04:40 |         MASTER-SAAO | (18h 35m 54.74s , -29d 22m 02.4s) |   C |    60 | 16.3 |        
   18886 | 2024-02-16 01:05:59 |         MASTER-SAAO | (18h 33m 53.01s , -31d 04m 57.6s) |   C |    60 | 17.0 |        
   18886 | 2024-02-16 01:05:59 |         MASTER-SAAO | (18h 40m 00.68s , -31d 16m 59.2s) |   C |    60 | 16.6 |        
   18966 | 2024-02-16 01:07:19 |         MASTER-SAAO | (18h 45m 19.22s , -33d 11m 57.5s) |   C |    60 | 17.1 |        
Filter C is a clear (unfiltred) band. 


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