Kaspar Von Braun
IPAC
 

"Directly Determined Radii and Effective Surface Temperatures of Exoplanet Host Stars"
 

The formation, evolution, and environment of extrasolar planets are heavily influenced by their respective parent stars, including location and extent of the habitable zone. To provide constraints on the characterization of these planets, it is therefore of significant scientific value to directly determine astrophysical parameters of the host stars. Of particular interest are stellar radius and effective surface temperature since the combination of these two parameters will determine the luminosity of the star, and, in turn, the radiation an extrasolar planet receives for given orbital radius. We used the Palomar Testbed Interferometer (PTI) to measure angular diameters of exoplanet host stars (EHSs) with known Hipparcos parallaxes. Using multiband literature photometry, spectral energy distribution fitting allowed us to determine astrophysical parameters of nine EHSs. We present our results on these stars and give comparisons to literature values. Finally, we give a statistical comparison between astrophysical properties of the nine EHSs and a set of ~20 control stars observed in the same manner at PTI.