Inferred minimum companion masses and mass ratios of binaries with well-constrained orbits. Left: minimum companion masses m₂ plotted against primary mass m₁ for the reduced subset of binaries with uni- (blue) and bimodal (red) posterior solutions in 47 Tuc. The dashed line indicates a mass ratio of q = 1, the dotted line marks the approximate hydrogen burning limit. Right: primary stellar radius R₁ divided by the determined (minimum) binary semi-major axis a as a function of minimum mass ratio. The color scheme is the same as in the left-hand figure. The dash-dotted line indicates the Roche radius. The black diamond marks a binary with a possible white dwarf companion.