[vsnet-alert 10794] Re: re ST CHA in outburst?

[Boris.Gaensicke at warwick.ac.uk]

Hi John et al. 

> Only potential evidence going for CVness now is this filled in ugz/nl - 
> esque thing you mentioned re their spectrum, if said is uniquely 
> diagnostic for ugz/nl?

the AAVSO data (all from Rod Stubbings, it seems) suggest real  
variability by ~2mag,

http://www.aavso.org/cgi-bin/lcg.pl?name=st%20cha&lastdays=800&start=&stop=&obstotals=on&grid=on&pointsize=1&width=600&height=450&mag1=&mag2=&mean=&visual=on&uband=on&bband=on&v=on&r=on&iband=on&j=on&h=on&unknown=on&fainterthan=on&unvalidated=on

That, coupled with the spectrum in Steiner's paper makes a UGZ or NL 
nature very likely.

Yes, the evidence for eclipses is not too strong, but one or two solid 
nights of time series should (dis)prove that claim. Berto reported a 4h 
run with no clear variability - that may have been bad luck, if the period 
is indeed 7h. Finding an eclipsing long-period UGZ or NL seems worth that 
investment... and if it is not eclipsing, than at least records can be 
corrected. 

Any volunteers out there?

As for establishing whether it is a UGZ or a NL, more intense (daily) 
monitoring will tell.

Cheers, 

Boris