[vsnet-grb-info 27486] Fermi trigger No 636187116: Global MASTER-Net observations report

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29589
SUBJECT: Fermi  trigger No 636187116: Global MASTER-Net observations report 
DATE:    21/02/28 18:00:37 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(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 GRB210228.28 (trigger No 636187116,06h 06m 28.80s , -41d 17m 24.0s, R=1) errorbox  34607 sec after notice time and 40338 sec after trigger time at 2021-02-28 17:50:49 UT, with upper limit up to  16.9 mag. Observations started at twilight.  The observations began at zenith distance = 12 deg. The sun  altitude  is -8.3 deg. 

The galactic latitude b = -25 deg., longitude l = 248 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1557721

We obtain a following upper limits.  

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

   40369 | 2021-02-28 17:50:49 |         MASTER-SAAO | (06h 01m 25.31s , -43d 08m 17.8s) |   C |    60 | 16.3 |        
   40449 | 2021-02-28 17:52:09 |         MASTER-SAAO | (06h 11m 27.87s , -41d 09m 11.1s) |   C |    60 | 16.8 |        
   40608 | 2021-02-28 17:54:49 |         MASTER-SAAO | (06h 01m 07.25s , -39d 08m 08.8s) |   C |    60 | 16.9 |        
Filter C is a clear (unfiltred) band. 


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