Electromagnetic cyclotron-loss-cone instability associated with weakly relativistic electrons
Abstract
The amplification of fast extraordinary mode waves with frequencies very close to the electron cyclotron frequency is investigated for a plasma which consists of a weakly relativistic electron component with a loss-cone type distribution and a cold background electron component. The basic mechanism of the amplification is attributed to a relativistic cyclotron resonance between the wave and the energetic electrons. The method employed in the present analysis enables us to solve the dispersion relation in a self-consistent manner for arbitrary ratio of the densities of the energetic and background electrons. It is found that the maximum growth rates occur at certain values of ω2pe/Ω2e and the angular dependence of the growth rate is sensitive to the ratios ω2pe/Ω2e and ne/nb. Here ωpe and Ωe are the electron plasma frequency and the electron cyclotron frequency, respectively, and ne and nb denote the number densities of the energetic and background electrons, respectively.
- Publication:
-
Journal of Plasma Physics
- Pub Date:
- December 1982
- DOI:
- 10.1017/S0022377800000453
- Bibcode:
- 1982JPlPh..28..503W
- Keywords:
-
- Cyclotron Frequency;
- High Energy Electrons;
- Plasma Waves;
- Relativistic Particles;
- Relativistic Plasmas;
- Wave Amplification;
- Distribution Functions;
- Electric Fields;
- Interstellar Masers;
- Plasma Frequencies;
- Plasma Physics