[vsnet-alert 3266] Re: Nova Aql 99 photometry

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

On Wed, 21 Jul 1999, Center for Backyard Astrophysics Brno station wrote:

> Dear colleagues,
> 
> we made ~2 hours long run in R band and found only linear change of brightness.No oscilations larger that 0.01 mag were observed. CCD ST-7 on 0,4m Newtonian was used.
> 
> With best regards
> 
> Rudolf Novak
> Nicholas Copernicus Observatory Brno, CZech Republic
> 
> -- http://email.seznam.cz 
> -- email zdarma na cely zivot
> 
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The importance of such observations has been discussed by me in details
before in the vsnet. In summary, finding periodicities in the light curves
of young novae would:

1. Improve the statistics of orbital periods in novae, which are still
   poor (only last week I tried to prove a point, and found out that more
   data are needed). 

2. Tells us about the evolution of the accretion processes in these 
   systems.

3. It should teach us more about the relation between novae and other
   subclasses of CVs, and perhaps help to rule out a few of the 
   evolutionary scenarios, which are still controversial.

Assuming that the mV=8.8 mag represents the maximum brightness of Nova 
Aql 1999, the nova is currently ~3 mag below maximum. According to my 
experience it might be a bit early for a periodicity search, which should
be more fruitful when the nova decays by ~2 more mags. Anyway, since
typical nova periods range between ~2-10 hours (with a peak around 
~3.5-4 hr), a 2-hr run is usually useless unless spin periods of the
rotating white dwarfs are observed. Longer runs and red filters are
preferred.

Regards,
Alon
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   Dr. Alon Retter         Tel. (work)     +44-(0)1782-58-3493
   Physics Dept.           Fax  (work)     +44-(0)1782-711093
   Keele University        -----------------------------------
   Staffordshire           'As a scientist I don't believe myself, so
   ST5 5BG, U.K.            why should I believe you?' (A.R. 1965-2085)
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