Implications for Solar-Type Binary Statistics of the Morbey-Griffin Improved Binary Analysis

We do not contest the preceding results by Morbey and Griffin but rather congratulate those authors on their improved instrumental and statistical methods. We ask here about the effects upon the binary statistics of solar-type stars of deleting the unconfirmed binaries. Specifically we assumed, in accord with Morbey and Griffin's recommendations, that all sharp-lined systems with orbital velocity amplitudes K₁ < 8.0 km s⁻¹ are undetected, as well as all broad-lined systems with K₁ < 12.0 km s⁻¹. After deleting 15 such binaries, there is some compensation by deriving larger correction factors for undetected binaries, namely six more. We find no significant change in the binary frequency for periods of 10⁻³ - 1O⁻¹ yr, a marginal reduction of 28% ± 24% in the numbers of binaries in 10⁻¹ -10 yr, and no changes at all for longer periods. The two forms of the secondary mass functions for periods greater than or less than 100 yr are unchanged.