Dynamical Friction in Binary Systems
Abstract
The energy loss rate from dynamical friction for a binary traveling uniformly through a homogeneous collisionless background such as the dark matter in the Galactic disk is calculated for the case that the orbital velocity is small compared with the background's velocity dispersion. The basic equation for Fourier components of the perturbation imprinted on the background's distribution function by the binary components is obtained. It is shown that one term of this basic equation contributes an energy loss just like that which Chandrasekhar's formula would predict were the binary components treated independently. The energy loss contributed by the other term of the basic equation is approximated and its order of magnitude is found to be similar to the Chandrasekhar term, but the logarithmic cutoff factor is replaced by one involving the number of completed binary orbits, so that there is a secularly growing part of the energy loss rate.
 Publication:

The Astrophysical Journal
 Pub Date:
 August 1990
 DOI:
 10.1086/169075
 Bibcode:
 1990ApJ...359..427B
 Keywords:

 Binary Stars;
 Chandrasekhar Equation;
 Computational Astrophysics;
 Dark Matter;
 Friction;
 Stellar Motions;
 Perturbation Theory;
 Pulsars;
 Stellar Evolution;
 Stellar Orbits;
 Astrophysics;
 DARK MATTER;
 INTERSTELLAR: MATTER;
 STARS: BINARIES;
 STARS: STELLAR DYNAMICS