Fraction of the radial velocity stable stars in the early observations of the Grid Giant Star Survey

Abstract

The GGSS is a partially-filled, all-sky survey to identify K-giant stars with low level of RV-variability. We study histograms of the radial velocity (RV) variability obtained in the early phase of the Grid Giant Star Survey (GGSS, Bizyaev et al., 2006). This part of the survey has been conducted with a very limited nubmer of observations per star, and rough accuracy. We apply the Monte-Carlo simulations to infer a fraction of the RV-stable stars in the sample. Our optimistic estimate is that 20% of all considered K-giants have RV-variability under 30 m s$^{-1}$. Different assumptions of intrinsic RV-variability for our stars give 12 -- 20 % of RV-stable K-giants in the studied sample.