[vsnet-obs 22606] re Nova Cir 1999 photometry (Garradd)

[Alon Retter <ar@astro.keele.ac.uk>]

Hi Gordon,

While you know my interest in young novae, I must say, that my 
opinion about continuous photometry of novae straight after the 
outburst is very negative. During the first stage of the nova, the 
binary system is believed to be in the common envelope phase - the 
2 stars are engulfed within this envelope, and there is no chance 
to observe periodicity. This would not be true if the 2 stars are 
far away from each other, but then the periodicity would be very 
long. Anyway, the immense light from the outburst would ruin any 
chance to find periodicities so early. Therefore, one should wait 
until the nova decays at least 4-5 mag before searching for periods. 
The decrease in the light is the dominant parameter (not the time 
elapsed since the outburst!). 

Despite everything I said, I do encourage tests of the theories, 
which might be wrong.

Anyway, I've checked your data, and could not find evidence for
a short-term periodicity. 

I don't think that you see flickering in the light curve. It looks to 
me like errors. To my knowledge the cause for flickering is still 
unknown, but they might be formed either in the immediate vicinity 
of the white dwarf or near the bright spot. None would be seen at this 
early stage of the nova. 

According to my experience, Nova V382 Vel 1999 and Nova Aql 1999, 
currently ~4-5 mag below maximum are very nice targets for the period
search.  If you, however, decide to observe them, try at least 2
successive full nights for this purpose.

Cheers,
Alon
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