[vsnet-alert 5981] Re: AL Com

[Taichi Kato <tkato>]

Re: AL Com

> Just some time ago I stoped (because of clouds) my run on AL Com 
> described before. So I was able to compare all data obtained here at 
> Brno (I don't know state on VSNET team now). Light curve shows linear 
> trend observed for many last days but data from yestarday and today 
> seems to cover a dip. Yesterday I observed AL Com using 60cm Newton and 
> when I finished Petr Sobotka kindly continued using 40cm Newtonian. 
> Combined data show very rapid rising. The observation finished right now 
> shows in oposite slow fading. This may indicate that the dip known in AL 
> Com (and in V 2176 Cyg for example) was a tenths of hours before.

   Because of the intermittent network shutdown, the message arrived
with a substantial delay.  Sorry that we have not been able to include
this information in the AstroAlert message.

   Great job!!!

   The same feature, but was not well observed, of the 1995 superoutburst
of AL Com has just repeated!  We consider this is a normal outburst
(as a variety of post-superoutburst rebrightening), and the present rise
seems to be a way to the possible second superoutburst.  In the 1995
superoutburst of AL Com, the presence of a precursor short outburst
has been considered as evidence that a normal outburst triggered the
second superoutburst, whose mechanism is not yet theoretically explained.

   The present great observation will open a new era of observations
of WZ Sge-type dwarf novae!  Congratulations to Rudolf, and all observers
involved!  Please keep the present extensive coverage, to fully follow
the evolution of the second superoutburst.  Never be tired :-)

Regards,
Taichi Kato
VSNET Collaboration team

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