Thermal relaxation of a two-dimensional plasma in a d.c. magnetic field. Part 1. Theory

A theory is presented for the rate of thermal relaxation of a two-dimensional plasma in a strong uniform d.c. magnetic field. The Vahala—Montgomery kinetic description is completed by providing a cut-off time for the time of interaction of two particles which contribute to the collision term. The kinetic equation preclicts that thermal relaxation occurs as a function of the dimensionless time (ω_pt) (ω_p/Ω) (n₀λ²_D)^-½, where ω_p, is the plasma frequency, Ω is the gyrofrequency, and n₀ λ²_D is the number of particles per Debye square. By contrast, in the absence of an external magnetic field, a two-dimensional plasma relaxes as a function of (ω_pt) (n₀λ²_D)^-1.