Multiple stars: physics vs. dynamics

R.Zhuchkov, V.Orlov, A.Rubinov

Kazan State University, St.~Petersburg State University


Abstract

We review the physical and dynamical parameters of multiple stars.
Possible scenaria of multiple star formation are discussed:
their birth in dense cloud cores,
decay of small stellar groups and clusters.
We compare physical and dynamical features of multiple stars
to be formed as a result of these processes simulations with
the actual multiple stars. Multiplicity function,
mass spectrum of components, their period, eccentricity and mass
ratio distributions, hierarchy of the structures are analysed.
Also we discuss multiple systems where the ages of the
components are sufficiently different.
The following possible explanations of such phenomenon are suggested:
an imperfection of evolutionary tracks for low-mass stars;
formation of such systems by capture;
merging of components during dynamical evolution of multiple stars.