[vsnet-alert 7430] observation of sgrv4641

["Toni Scarmato" <toniscarmato@hotmail.com>]

Dear all,

very interesting observation of SGRV4641 this  night with my 203 mm SCT,
f/10, 70x and 140x, unfiltered.
Good conditions of the sky beetwen 22.37 and 00.02 Local Time with the
"star" at ~12.0v magnitude during the quiescence fase.

Those are two series of flares observed:

first series

20020708.859 11.4v TSc flare
20020708.864 11.0v TSc flare
20020708.866 10.5v TSc "big" flare at maximum for 4 seconds, steady state at
mv=11.4 for 20 seconds, fading 2 second
20020708.870 11.2v TSc flare
20020708.875 11.3v TSc flare
20020708.879 11.0v TSc flare

second series

20020708.911 11.3v TSc flare
20020708.915 10.7v TSc big flare for at maximum 8 seconds  fading 2 second
not steady state
20020708.918 11.4v TSc flare at maximum for 30 seconds.


It is interesting to note that during the maximum of the flares the emission
surface is not of stellar shape but show a central side that appear as a
star and an exsternal side about 1' diffuse but with an intense emission in
visual band.
Also, beetwen a flare and other, the "star" have had other irregular
oscillations of brightness but of smaller intensity.


Best Regards,

Toni Scarmato

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