The Frequency Distribution of Semi-major Axis of Wide Binaries. Cosmogony and Dynamical Evolution

摘要: The frequency distribution f(a) of semi-major axis double and multiple systems, as well their eccentricities mass ratios, contain valuable fossil information about the process star formation dynamical history systems. In order to advance in understanding these questions, we have made an extensive analysis f (a) for wide binaries (a>25 AU) various published catalogues, our own (Poveda et al., 1994; Allen 2000; Poveda & Hernandez, 2003). Based upon all studies established that is function age system follows Oepik's ~ 1/a range 100 AU < a a[c](t), where a[c](t) critical beyond which dissociated by encounters with massive objects. We argue physics behind energy relaxation, analogous present stellar clusters (secular relaxation) or spherical galaxies (violent relaxation). ratios triple systems existence runaway stars, indicate both types relaxation are important binary formation.