Brownian Motion of a Dust Molecule

The dynamics of the bound complex consisting of two particles and being under the action of external random forces is studied theoretically. It is assumed that the interparticle forces are nonreciprocal. It is shown that, in the general case, the mean-square fluctuations of the velocities of different particles differ from each other and from the thermostat temperature. Numerical calculations of the dynamics of Brownian particles in plasma consisting of the Boltzmann electrons and directed ion flow have been performed.