Interference effects in the long-time tail of the velocity auto-correlation function for a dense one-component plasma in a magnetic field

The long-time behaviour of the velocity autocorrelation function that describes the motion of a tagged particle through a one-component plasma in a uniform magnetic field has been determined with the use of mode-coupling theory. The long-time tail depends on the orientation of the velocity with respect to the magnetic field. Owing to the anisotropy of the collective mode spectrum the mode-coupling integrals are afflicted with interference effects. As a consequence the long-time behaviour of the velocity autocorrelation function for a plasma in a magnetic field differs qualitatively from that found for an unmagnetized plasma.