A PHOTOMETRIC ANALYSIS OF THE APSIDAL MOTION BINARY-SYSTEM PV CASSIOPEIAE

Thirty-one nights of UBV(RI)c photometry of the apsidal-motion binary system PV Cassiopeiae are presented. Timings for six primary and eight secondary minima have been determined. With the new photometry, we performed new orbital solutions with the NDE model. Reflection was found to be moderately important and the limb-darkening coefficient for the U filter to be significantly higher than theory. In these new solutions, not only is the secondary component the more massive, it is also the more luminous and larger of the two components. The colors for both components of PV Cas suggest a B9.5 V spectral type, which, together with the adopted masses and radii, are consistent with relatively unevolved main-sequence stars. An orbital eccentricity of 0.032 was adopted for the system. We determined a new nonlinear ephemeris, which provides a period of apsidal motion of U=94±2 years. An internal structure constant of log k2=-2A7 results. © 1995 American Astronomical Society.