Spectra of high-frequency waves in hot magnetized plasmas

Abstract

533.9On the basis of numerical solution of the dispersion equation, we obtain the spectra of weakly damped high-frequency waves in a hot magnetized plasma for the case where the electron cyclotron frequency ω He is below the plasma frequency ω pe . It is shown that the longitudinal wave propagating at an angle to the magnetic field evolves into the slow extraordinary wave for the refractive index n ≤ 1. For n 1, the longitudinal-wave frequency increases with the refractive index, and the wave evolves into the wave with anomalous dispersion if the angle θ between the wave vector and the magnetic field is close to 90 • . In the same range of θ angles, Bernstein modes appear in the spectrum of plasma eigenmode oscillations.

High-frequency waves in a hot plasma in a moderately strong magnetic field

“…A significant effect influencing the properties of the plasma in this case is that of the finite Larmor radius of electrons (effect of strong spatial dispersion), which manifests itself if the wavelength and the electron gyroradius become of the same order of magnitude. The dispersion properties of high-frequency waves (for which ω > ω He , where ω is the wave frequency and ω He is the electron gyrofrequency) in a hot magnetoplasma were studied in [6,7] in the case where the electron plasma frequency ω pe exceeds the electron gyrofrequency. In [6], the dispersion surfaces were plotted for waves in the plasma with fixed parameters which corresponded to the parameters of the Earth's magnetosphere.…”

“…In [6], the dispersion surfaces were plotted for waves in the plasma with fixed parameters which corresponded to the parameters of the Earth's magnetosphere. In [7], we studied the properties of such waves in the plasma having a temperature corresponding to that of the solar corona. The calculations were performed for different values of the plasma parameters with allowance for wave attenuation.…”

“…Figures 1-6 show the results of solving Eq. (1) with the help of the formulas from the Appendix in [7] as the dependences of the refractive index n on the frequency. The solutions of Eq.…”