q(α) reconsidered

The distribution of mass ratios in spectroscopic binaries, q(α), has been brought up to date and plotted in a slightly more sensible way. All features of the previous determination persist. The most important of these is bimodality: q(α) has peaks near M2/M1 = 0.2 to 0.3 and 0.9 to 1.0. Every subsample, including unevolved systems, also displays this double-peaked distribution function. It probably implies that binaries are formed by two mechanisms, acting like fission and capture. (author)