WHISTLER DETERMINATION OF ELECTRON ENERGY AND DENSITY DISTRIBUTIONS IN THE MAGNETOSPHERE,
Abstract
Fiftty-seven nose whistlers recorded at five stations between April 1958 and June 1962 were employed to test the validity of model magnetospheric electron distributions and two theories for the upper cutoff frequency of the whistler signal. Five electron density distributions were tested. In some cases, the ratios of the upper cutoff frequency to the equatorial gyrofrequency, are scattered with most whistlers having the ratio >0.5. This indicateees that the cutoff is probably not caused by escape of high-frequency components fro1m field-aligned ducts. On the other hand, the assumption that the cutoff above the upper cutoff frequency is caused by a thermal Dopplerr shift in the cyclotron resonance is strongly supported. For these whistlers the resonant particle energies at the upper cutoff frequency range between 0.2 and 2.0 keV and in this interva1l the differential energy spectrum of the normalized density is a remarkably smooth fauunction which varies as 1/E with no significant height or time variation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1963
- Accession Number
- AD0421010
Entities
People
- F. L. Scarf
- H. B. Liemohn
Organizations
- Boeing