Accession Number : AD0783512

Title :   Investigation of Phenomena Affecting Auroral Ionosphere.

Descriptive Note : Final rept. 1 Mar 73-30 Apr 74,

Corporate Author : LOCKHEED MISSILES AND SPACE CO INC PALO ALTO CALIF PALO ALTO RESEARCH LAB

Personal Author(s) : Cladis,J. B. ; Davidson,G. T. ; Francis,W. E. ; Newkirk,L. L. ; Walt,M.

Report Date : 09 JUL 1974

Pagination or Media Count : 70

Abstract : Rocket data obtained during a magnetic substorm on 16 August 1970 indicates the auroral ionosphere was unstable to the high-frequency, Hall current, two stream instability. This mechanism has been proposed to explain field-aligned ionospheric irregularities. Such irregularities were present during the rocket experiment. According to the theory, certain critical values of electron number density, current density, and relative electron-ion drift velocity must be exceeded for the instability to occur. An analysis is described in which calculated values of these quantities are derived from the rocket measurements of the dc electric field and the precipitating electrons. The results are found to exceed the respective critical values and enforce the conclusion that the field-aligned irregularities were produced by this instability. (Modified author abstract)

Descriptors :   *IONOSPHERIC DISTURBANCES, *AURORAE, MAGNETIC STORMS, ELECTRON DENSITY, ION DENSITY, WHISTLERS, MAGNETOSPHERE

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE