Statistical analysis of single-lined red giant spectroscopic binaries.

This article reports a statistical analysis of the orbital elements (period, eccentricity, mass function) performed on a sample of 194 single-lined red giant spectroscopic binaries. From the eccentricity-period diagram, the authors deduce a circularization cut-off period of 70 days and find an eccentricity-period correlation that seemingly does not result from an observational bias. With the aid of two complementary methods, the authors derive the mass ratio distribution. A comparison with the observed mass function distribution shows a reasonably good agreement in the case of an uniform mass ratio distribution function and a single-valued giant mass of 1.5 M_sun. The authors finally present a comparison with a sample of barium stars.