Whistler-mode propagation at frequencies near the electron gyrofrequency

Abstract

Parallel whistler-mode propagation in a hot anisotropic plasma at frequencies near the electron gyrofrequency is considered by using analytical methods and a simple graphical technique, without any special restrictions on the value of the imaginary part of the plasma dispersion function argument. An exact criterion for the possibility of whistler-mode propagation in the vicinity of the electron gyrofrequency is derived. In particular it is pointed out that whistlers in this frequency interval can propagate only in a very hot and rarefied plasma submerged in a strong magnetic field. These whistlers can only be damped, the modulus of the decrement of the damping cannot exceed 1·1 times the electron plasma frequency. The refractive index remains close to unity.