A STUDY OF THE MECHANISMS OF WHISTLER PROPAGATION AND VLF EMISSION GENERATION.
Abstract
The review is organized under three main topics: (1) Properties of the magnetosphere, (2) Propagation and Detection Studies, and (3) Wave-Particle Interactions. Using whistlers, plasma drift motion was detected in the magnetosphere for the first time, and this has been interpreted in terms of a magnetospheric electric field with a westward component of about 0.3 mv/m at an equatorial distance of 4 earth radii. The upper cutoff frequency of whistlers was found to be remarkably close to 1/2 the minimum gyrofrequency along the field-line path, providing strong evidence in support of the 'duct' cutoff theory of R. L. Smith. A sudden cutoff of whistler-mode signals was found at latitudes above the plasmapause. Research on wave-particle interaction theory has shown that previous theories have neglected the transient effects which are of importance in the interaction of whistlers with the medium. These results suggest that presently published theory on wave-particle interactions may be inapplicable to much of the whistler and discrete vlf emission phenomena. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1967
- Accession Number
- AD0648675
Entities
People
- R. A. Helliwell
Organizations
- Stanford University