Accession Number:

AD0753162

Title:

Radiation Induced F-Region Plasma Phenomena

Descriptive Note:

Technical rept.

Corporate Author:

PRINCETON UNIV NJ

Personal Author(s):

• Perkins, Francis W.
• Valeo, Ernest J.

Report Date:

1972-05-01

Pagination or Media Count:

31.0

Abstract:

Collective plasma phenomena induced in the ionospheric F-region by intense high-frequency radiation are examined on several time and length scales. The short wavelength, high-frequency turbulence associated with the observed high-frequency enhanced electron density fluctuations at the electron plasma frequency is shown to result from parametric excitation of plasma and acoustic waves by the high-frequency radiation. The wave kinetic equation describing the non-linear evaluation of the turbulence is presented. The time asymptotic spectral intensity is calculated and a formula for the total energy absorption from the incident radiation via nonlinear collective effects is obtained. A radiation induced self-focussing instability is found on a length scale somewhat larger than an ion Larmor radius. and is offered as a possible explanation for the occurrence of magnetic field aligned density filaments, which are associated with the phenomenon of artificial Spread-F. The calculated growth rates are in agreement with the time delay for appearance of spread-F after modifier turn on.

Descriptors:

• *IONOSPHERIC DISTURBANCES
• IONOSPHERIC PROPAGATION
• MAGNETIC FIELDS
• OSCILLATION
• TURBULENCE

Subject Categories:

• Atmospheric Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE