The properties of close multiple stars

摘要: A reexamination of the properties close multiple systems is conducted, taking into account recent numerical, analytical, and observational results. The orbital elements 43 spectroscopic are presented in a table. Tables with photometry data describing their also provided. Attention given to period ratios, mass coplanarity, stability, lithium abundances age estimates, prospects future observations. Numerical studies indicate that fragmentation produces binary components ratios usually 1.0, while fission range 0.1-0.5. Using analytical stability criteria, all 27 considered stable if they corotating. If counter-rotating, four possibly unstable. However, other factors suggest even these probably stable. solar-type ranged from 100 million years 2,000 years.