RE: GSC 0279 0321 is probably not an eclipser (also note on colour index use)

["Creager, Robert S" <CreagRS@LOUISVILLE.STORTEK.COM>]

Thanks for the discourse John.  One of those duh moments.

Gnuplot can easily handle two column arithmatic, and much more.  The Perl
scripts can easily create anoter column of info, at any point.

Cheers,
Rob

> -----Original Message-----
> From: jg [mailto:jg@jgws.freeisp.co.uk]
> Sent: Thursday, June 06, 2002 5:14 AM
> To: Tom Droege
> Cc: tass@listserv.wwa.com
> Subject: GSC 0279 0321 is probably not an eclipser (also note 
> on colour
> index use)
> 
> 
> NOTE : I don't know whether selectun and gnuplot are amenable 
> to on the
> fly creation of V-I values for plotting or whether this would 
> have to be
> done separately, as the data output does not include V-I, but 
> the colour
> index would make an immediate diagnostic tool for EA stars 
> where patchy
> lightcurves have hints of minima and maxima in the TASS CD 
> datasets but
> the light curve is not well sampled.  There are quite a few of these
> amongst the variable star candidates.  Maybe it should be included in
> the data, this would however make the .cal and .big files 
> bigger, due to
> including an extra column of information.  Not certain as to 
> whether it
> would also be increasing processing time as I am not even remotely
> familiar with perl, whether it's a compiler or an interpreter, nor how
> fast it works, so I'm not sure whether it is worth the effort.  It is
> certainly not primary but derived data, but then again where does
> primary data end and derived data start?
> 
> Ironically, this would not so much be to choose EA stars as to discard
> them.  Some people simply find them less interesting, but on a more
> objective point, it looks like there's a one day selection effect  in
> the periods (or two minima 2 d or 1/2 d that can appear 1 to 
> be one day
> in gapped data).  EA stars with these periods will need a 
> great deal of
> observational follow up to sort them out, whereas pulsating stars will
> probably soon reveal their nature, even if their period turn 
> out to be a
> large fraction submultiple of a day.  If you don't have a full
> _continuous_ lightcurve for an eclipser it is hardy to be certain that
> you haven't missed a secondary eclipse in some cases, whereas gapped
> data for pulsators can be folded and solved quite nicely in similar
> circumstances.
> 
> Just thoughts.
> 
> 
> Cheers
> 
> John
> 
> John Greaves
> UK
> 
> 
> PS The HAT paper contains about the 8th different way I've 
> ever seen the
> GSC number denoted (re graphs in it), though this is the 
> first time I've
> ever seen the two sets of numbers running together without a delimiter
> of any kind.  This is _non-preferred_, as the GSC numbers are not one
> number but two.
>