Kepler Follow-up Observation Program. II. Spectro.

Two samples of stars were observed over 6yr (2009-2015): 614 standard stars (divided into "platinum" and "gold" categories) selected based on their asteroseismic detections and 2667 host stars of Kepler Objects of Interest (KOIs), most of them planet candidates.

Four data analysis pipelines were used to derive stellar parameters for the observed stars. We compare the Teff, log(g), and [Fe/H] values derived for the same stars by different pipelines; from the average of the standard deviations of the differences in these parameter values, we derive error floors of ~100K, 0.2dex, and 0.1dex for Teff, log(g), and [Fe/H], respectively. Noticeable disagreements are seen mostly at the largest and smallest parameter values (e.g., in the giant star regime).