  We propose to measure the radii of the Penn State - Torun Planet Search
(PTPS) exoplanet host star candidates using the CHARA Array. Stellar radii
estimated from spectroscopic analysis are usually inaccurate due to indirect
nature of the method and strong evolutionary model dependency. Also the
so-called degeneracy of stellar evolutionary tracks due to convergence of many
tracks in the giant branch decreases the precision of such estimates. However,
the radius of a star is a critical parameter for the calculation of stellar
luminosity and mass, which are often not well known especially for giants. With
well determined effective temperature (from spectroscopy) and radius the
luminosity may be calculated precisely. In turn also stellar mass may be
estimated much more precisely. Therefore, direct radii measurements increase
precision in the determination of planetary candidates masses and the surface
temperatures of the planets.
