SIMULTANEOUS LIGHT AND RADIAL-VELOCITY CURVE SOLUTIONS FOR U-CEPHEI

The light-curve synthesis approach of Wilson & Devinney has been used to solve simultaneously light and radial velocity curves of the Algol-type eclipsing binary star U Cephei. We have performed eight new differential corrections solutions using the photometric data of Markworth and the radial velocity data of Batten to obtain a consistent set of orbital and astrophysical parameters for the light and velocity curves of this famous system. We find U Cephei to be best modeled using the semidetached (mode 5) system geometry of the Wilson & Devinney program, with a primary rotating at about 5.2 times its synchronous rate, and have found absolute system parameters to be M1 = 4.93 M., M2 = 3.27 M., R1 = 2.77 R., and R2 = 5.22 R..