Modulation of instabilities in the magnetosphere by hydrodynamic oscillations
Abstract
Theoretical calculations are presented which demonstrate that low-amplitude hydromagnetic oscillations periodically change the electron energy and pitch-angle distributions in the magnetosphere, thus modulating the increment of the cyclotron instability. As a consequence of this, both the intensity of VLF radiation and the precipitating-particle fluxes are modulated. It is shown that the modulation period depends on the reflection coefficient of VLF waves and may last for seconds or longer.
- Publication:
-
Low-Frequency Radiations and Signals in the Magnetosphere
- Pub Date:
- 1975
- Bibcode:
- 1975lfrs.rept....8T
- Keywords:
-
- Electron Precipitation;
- Magnetospheric Electron Density;
- Magnetospheric Instability;
- Plasma Oscillations;
- Very Low Frequencies;
- Cyclotron Frequency;
- Modulation;
- Particle Flux Density;
- Vlf Emission Recorders;
- Geophysics