Using Georgia State University's CHARA Array interferometer, we measured angular diameters for 25 giant stars, six of which host exoplanets. The combination of these measurements and Hipparcos parallaxes produce physical linear radii for the sample. Except for two outliers, our values match angular diameters and physical radii estimated using photometric methods to within the associated errors with the advantage that our uncertainties are significantly lower. We also calculated the effective temperatures for the stars using the newly-measured diameters. Our values do not match those derived from spectroscopic observations as well, perhaps due to the inherent properties of the methods used or because of a missing source of extinction in the stellar models that would affect the spectroscopic temperatures.
@article{arxiv.0912.5491,
title = {Angular Diameters and Effective Temperatures of Twenty-five K Giant Stars from the CHARA Array},
author = {Ellyn K. Baines and Michaela P. Doellinger and Felice Cusano and Eike W. Guenther and Artie P. Hatzes and Harold A. McAlister and Theo A. ten Brummelaar and Nils H. Turner and Judit Sturmann and Laszlo Sturmann and P. J. Goldfinger and Christopher D. Farrington and Stephen T. Ridgway},
journal= {arXiv preprint arXiv:0912.5491},
year = {2014}
}