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GCN Circular 17980

V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
2015-06-28T11:27:33Z (9 years ago)
Alexei Pozanenko at IKI, Moscow <>
E. Mazaeva (IKI), S. Schmalz (AIP), I. Reva (Fesenkov Astrophysical 
Institute), R. Inasaridze (AAO),  N. Tungalag (Research Center of 
Astronomy and Geophysics MAS), I. Molotov (KIAM), A. Volnova (IKI),  A. 
Pozanenko  (IKI) report on behalf of larger GRB follow-up

We are observing (Mazaeva et al, GCN 17940) the  V404 Cyg activity 
detected by BAT/Swift (Barthelmy et al., GCN 17929), GBM/Fermi (Younes, 
GCN 17932; Jenke GCN 17935),   Konus-Wind (Golenetskiiet al., GCN 
17938), MAXI (Negoro et al., ATel #7646), and INTEGRAL (Roque et al., 
ATel #7693) with Zeiss-1000 (East) 1-m telescope of Tien Shan 
Astronomical Observatory, ORI-40 0.4m telescope of ISON-Khureltogot and 
AS-32 0.7m telescope of Abastumani observatory. The V404 Cyg optical 
activity reported by many observatories is clearly visible in our 
observations on time scale of at least 60 s (time exposures of our 
observations in R and Clear filters are 60 and 30 s).

Preliminary light curves of the V404 Cyg activity in R-band  are following:

overall light curve obtained till now (no all data still reduced)

and zoom of each day since initial Swift trigger (Barthelmy et al., GCN 

Photometry is based on following USNO-B1.0 stars

ID              R2
1238-0434779    13.52
1238-0434864    14.12
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