Accession Number : AD0733336

Title :   The Patterns and Sources of High-Latitude Particle Precipitation.

Descriptive Note : Rept. for Jun 70-Jan 71,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Paulikas,George A.

Report Date : 01 NOV 1971

Pagination or Media Count : 121

Abstract : The paper surveys the properties of the zones of particle precipitation at high latitudes and considers the average properties of particle influx from the outer magnetosphere as determined by satellite and rocket observations as well as ground-based techniques. The paper tries to associate source regions, and, if possible, precipitation mechanisms with each of the families of precipitating particles which collectively form the auroral zone. The precipitation patterns for both electrons and protons exhibit a diurnal variation. The several zones of particle precipitation can be placed in relationship to each other. The zone of electron precipitation is best described as consisting of a region at low latitudes where electrons with characteristic energies of tens of keV precipitate; this region merges and overlaps at the higher latitudes with another region characterized by precipitating electrons of about 0.5 keV. The limited data available indicate that the zone of proton precipitation spatially overlaps the zone of electron precipitation. The plasma sheet, the extraterrestrial ring current, the polar cusp, and the outer radiation belt are considered as source regions of precipitating particles. Brief surveys of the precipitation of helium ions and of possible means of artificially inducing particle precipitation are also included. (Author)

Descriptors :   (*AURORAE, SOURCES), (*MAGNETOSPHERE, PARTICLE TRAJECTORIES), PROTONS, POLAR REGIONS, MAGNETIC STORMS, HELIUM, IONS, ELECTRON DENSITY

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE