We report here an analysis of the physical stellar parameters of the giant star HD 185351 using Kepler short-cadence photometry , optical and near infrared interferometry from CHARA , and high-resolution spectroscopy .
Asteroseismic oscillations detected in the Kepler short-cadence photometry combined with an effective temperature calculated from the interferometric angular diameter and bolometric flux yield a mean density , \rho _ { \star } = 0.0130 \pm 0.0003 \rho _ { \odot } and surface gravity , \log { g } = 3.280 \pm 0.011 .
Combining the gravity and density we find R _ { \star } = 5.35 \pm 0.20 R _ { \odot } and M _ { \star } = 1.99 \pm 0.23 M _ { \odot } .
The trigonometric parallax and CHARA angular diameter give a radius R _ { \star } = 4.97 \pm 0.07 R _ { \odot } .
This smaller radius , when combined with the mean stellar density , corresponds to a stellar mass 1.60 \pm 0.08 M _ { \odot } , which is smaller than the asteroseismic mass by 1.6– \sigma .
We find that a larger mass is supported by the observation of mixed modes in our high-precision photometry , the spacing of which is consistent only for M _ { \star } \gtrsim 1.8 M _ { \odot } .
Our various and independent mass measurements can be compared to the mass measured from interpolating the spectroscopic parameters onto stellar evolution models , which yields a model-based mass M _ { \star, model } = 1.87 \pm 0.07 M _ { \odot } .
This mass agrees well with the asteroseismic value , but is 2.6– \sigma higher than the mass from the combination of asteroseismology and interferometry .
The discrepancy motivates future studies with a larger sample of giant stars .
However , all of our mass measurements are consistent with HD 185351 having a mass in excess of 1.5 M _ { \odot } .