Accession Number : AD0664423

Title :   PROPAGATION CHARACTERISTICS OF PLANE SMALL AMPLITUDE HYDROMAGNETIC DISTURBANCES IN THE EARTH'S UPPER ATMOSPHERE,

Corporate Author : TEXAS UNIV AUSTIN ELECTRICAL ENGINEERING RESEARCH LAB

Personal Author(s) : Bostick,F. X. , Jr. ; Prince,C. E. , Jr. ; Smith,H. W.

Report Date : 15 JUL 1964

Pagination or Media Count : 113

Abstract : From the equations of motion, continuity and state, written for a gas consisting of electrons and a single species of positive ions and neutral particles together with Maxwell's equations, the general dispersion relation for plane small amplitude hydromagnetic waves is derived. This relation, a polynomial of the fifth degree in the square of the propagation constant, is solved numerically for medium parameters representative of those encountered in the earth's upper atmosphere. Each of the five roots of the dispersion relation represents a different wave type. Two of the five wave types may be described as essentially transverse waves with the component field fluctuations occurring in planes perpendicular to the direction of propagation. Three of the wave types are longitudinal type waves in which the field component fluctuations occur in planes parallel to the direction of propagation. Of the five wave types, only the two transverse waves appear to be responsible for the transmission of significant amounts of energy through the upper atmosphere. One of the wave forms, qualitatively described as a sound wave in the electron gas, is evanescent throughout the geomagnetic micropulsation frequency range and therefore should not exist with an appreciable amplitude anywhere in the upper atmosphere at those frequencies. (Author)

Descriptors :   (*UPPER ATMOSPHERE, MAGNETIC FIELDS), (*ELECTROMAGNETIC RADIATION, IONOSPHERIC PROPAGATION), GAS IONIZATION, PERTURBATION THEORY, WAVE PROPAGATION, ATTENUATION, ELECTROMAGNETIC PROPERTIES, MAGNETOHYDRODYNAMICS, NUMERICAL ANALYSIS, GEOMAGNETISM, CHARGED PARTICLES

Subject Categories : Atmospheric Physics
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE