[vsnet-grb-info 28502] Swift GRB210807.78: Global MASTER-Net observations report

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  30605
SUBJECT: Swift GRB210807.78: Global MASTER-Net observations report 
DATE:    21/08/07 19:11:19 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) was pointed to the Swift GRB210807.78 (trigger No 1064377,16h 20m 31.75s , -15d 53m 51.4s, R=0.05) errorbox  12 sec after notice time and 153 sec after trigger time at 2021-08-07 18:44:14 UT, with upper limit up to  18.5 mag. The observations began at zenith distance = 20 deg. The sun  altitude  is -33.7 deg. 

The galactic latitude b = 23 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=1683617

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

     169 |         MASTER-SAAO | P\  |    30 | 17.0 |        
     215 |         MASTER-SAAO | P\  |    40 | 18.3 |        
     274 |         MASTER-SAAO | P\  |    50 | 18.5 |        


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