Photoelectric light curve of the Algol system TW Andromedae and the interpretation of its distortions by the effects of hot spots.
Summary. Photoelectric observations in B and V of this semi-detached Algol system obtained in are discussed. In distinction to the usual method of treatment of observations, the parameters of rectification have been derived only from those parts of the light curves which, according to recent ideas on gas streams in Algol systems, could be assumed to be clear of the influences of them. As soon as the light curve outside of eclipses had been freed from the effects of reflection and ellipticity in this way, there remained systematic distortions which could be explained by the existence of an additional light source of about 3 % of the intensity of the uneclipsed system. This light source is situated on the bright F-component at high latitudes in front of the subgiant. It disappears twice during one period of revolution of the system: once whilst it is hidden by the F-star itself for about one half of the period, and for a second time within the course of the primary eclipse. The B- and V-observations could be represented satisfactorily by the same geometrical parameters of the system. Light from a third star is present. Key words: binaries - Algol Systems - hot spots
Astronomy and Astrophysics
- Pub Date:
- April 1973