On the study of the mass ratio of spectroscopic binaries

We present a new algorithm to derive the true mass-ratio distribution of an observed sample of spectroscopic binaries. The algorithm includes an iterative procedure in which each binary of unknown inclination is replaced by an ensemble of virtual systems with a distribution of inclinations. This work shows that contrary to a widely held assumption, the inclination angles of each virtual ensemble should not be distributed randomly in space. We also suggest a way to account for the observational selection effect associated with the inability to detect single-line spectroscopic binaries with low-amplitude radial-velocity modulation. We present several numerical simulations which demonstrate the advantage of the new algorithm compared with the classical method to determine binary mass-ratio distribution.