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The Ellipsoidal Variable b Persei


Steven L. Morris

Los Angeles Harbor College, Physics Dept., Wilmington, CA 90744

Received February 26, 2014; revised March 19, 2014 and April 4, 2014; accepted May 1, 2014


The bright (V = 4.6) ellipsoidal variable b Persei is unique, as it is a triple system that experiences an eclipse of the primary and secondary stars every 701.76 days by the tertiary component. This paper analyses the ellipsoidal light variations to show that the mass ratio is q = 0.28 ± 0.02 and the inclination is i = 43 ± 3°. Modeling the system with the Wilson-Devinney computer code leads to similar values of q = 0.25 ± 0.03 and i = 49 ± 10°.

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