[Aavso-photometry] Eclipsing binary magnitude ranges on AAVSO charts

[Patrick Wils]

> If you then look at Simbad's references, you can find some detailed
> studies of the system.  A particularly good one is 	
> Srivastava, R. K., "Photoelectric elements of the eclipsing binary
> ST Persei," 1970BAICz..21..219S
> 
> In there, the author gives light curves in B&V, relative to the
> selected comparison star (BD +38 607; TYC 02851-01660;
> 03:00:16.79, +39:27:12.1). It shows the differential V range to be
> -0.3 to +1.5, or 1.8 magnitudes.  If we assume V=9.5 at maximum,
> this would mean that the star should be 11.3 at minimum,
> which is why the GCVS gives the range it does.  The range is much
> more in B, by the way - an amplitude of 2.4 magnitudes.

In 1976AcA....26...15W, Weis and Chen argue that Srivastava included the 11.8V companion (at 11"N from ST Per) in his aperture, so that the real amplitudes in B and V should be 3.6 and 2.8 mag respectively.  This would give mag 12.3V in minimum, much more in agreement with Yenal's observation.

Patrick