Waves in the Plasmasphere — 4. Doppler Shifted Cyclotron Resonance of Electrons with Whistlers

Abstract

In the outer regions of the plasmasphere and in the plasmapause there is, as well as the cold plasma, a substantial population of energetic plasma of ring current origin. The highest energy particles of the van Allen belts are found on the innermost L-shells. In such regions v. l. f. waves are propagated in the whistler mode with the conditions being almost entirely determined by the cold plasma. Resonant hot electrons from the ring current population can cause amplification of existing waves or can be the source mechanism which generates waves in the whistler mode. The predominant interaction is Doppler shifted cyclotron resonance.