Electrostatic lower hybrid waves excited by electromagnetic whistler mode waves scattering from planar magnetic-field-aligned plasma density irregularities

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA095iA01p00149· OSTI ID:5254578

Bell, T F; Ngo, H D ^[1]

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1. Stanford Univ., CA (United States)

Recent satellite observations demonstrate that high amplitude, short wavelength (5 m {le} {lambda} {le} 100 m) electrostatic waves are commonly excited by electromagnetic whistler mode waves propagating in regions of the magnetosphere and topside ionosphere where small-scale magnetic-field-aligned plasma density irregularities are thought to exist. A new theoretical model of this phenomenon is presented, based upon passive linear scattering in a cold magnetoplasma. In this model the electrostatic waves are excited by linear mode coupling as the incident electromagnetic whistler mode waves scatter from the magnetic-field-aligned plasma density irregularities. The excited short wavelength waves are quasi-electrostatic whistler mode waves, a type of lower hybrid wave, whose wave normal lies near the whistler mode resonance cone where the wave refractive index becomes very large. The amplitude of the excited electrostatic lower hybrid waves is calculated for a wide range of values of input electromagnetic wave frequency, wave normal direction, electron plasma frequency, gyrofrequency, ion composition, and irregularity scale and density enhancement. Results indicate that high amplitude lower hybrid waves can be excited over a wide range of parameters for irregularity density enhancements as low as 5% whenever the scale of the irregularity is of the same order as the lower hybrid wavelength.

• OSTI ID: 5254578
• Journal Information: Journal of Geophysical Research; (United States), Vol. 95:A1; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH MAGNETOSPHERE
PLASMA DENSITY
PLASMA WAVES
IONOSPHERE
DIAGNOSTIC TECHNIQUES
ION DENSITY
IONIC COMPOSITION
MATHEMATICAL MODELS
SATELLITES
SCATTERING
VARIATIONS
WAVE PROPAGATION
WHISTLERS
EARTH ATMOSPHERE
ELECTROMAGNETIC RADIATION
NOISE
PLANETARY IONOSPHERES
RADIATIONS
RADIO NOISE
RADIOWAVE RADIATION
640201* - Atmospheric Physics- Auroral
Ionospheric
& Magetospheric Phenomena