[vsnet-alert 8500] V4641 Sgr on June 28-29: prominent optical flashes

[Makoto Uemura]

V4641 Sgr on June 29: prominent optical flashes

    B. Monard kindly sent us the data sets on June 28 and 29. 
The light curves shows several optical flashes; >0.5mag flares having 
durations < 1min.  Except for flares and flashes, the light curves 
clearly show ellipsoidal modulations.  General characteristics of 
the light curves are quite similar to those observed in post-outburst 
active phase in 2002 and 2004.  Now we meet a good chance to study 
the optical flash.  Multicolor photometry would provide a crucial clue 
for the optical flash.

Regards,
Makoto Uemura
Hiroshima University