Density drift instabilities and weak collisions

Journal Article · Tue Mar 01 04:00:00 EST 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA03p02103· OSTI ID:6267916

Gary, S P; Bernhardt, P A; Cole, T E

This paper describes the effects of weak collisions on the linear kinetic theory of electrostatic density drift instabilities. The model assumes a weak, uniform density gradient, a uniform magnetic field and the BGK collision operator with a modification of the local approximation to derive a dispersion equation valid at all frequencies and wave numbers. The properties of the universal and collisional density drift instabilities at maximum growth rates are presented in detail. Their thresholds in an ionospheric model, which includes ion-neutral, electron-neutral, and electron-ion collisions, are in an ionospheric model, which includes ion-neutral, electron-neutral, and electron-ion collisions, are discussed and compared with the threshold of the lower hybrid density drift instability. In particular, the ionospheric conditions (plasma density < or approx. =10/sup 6/ cm altitute > or approx. =250 km) and maximum scale lengths necessary to excite the universal at wavelengths of the order of the ion gyroradius are presented. We conclude that the k/sup -5/ short wavelength density power spectra observed above 280 km in the PLUMEX experiment are due to the effects of the universal density drift instability.

• Research Organization: Earth and Space Sciences Division, University of California, Los Alamos National Laboratory, Los Alamos, NM 87545
• OSTI ID: 6267916
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88:A3; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
&amp; Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COLLISIONS
DISPERSION RELATIONS
DRIFT INSTABILITY
EARTH ATMOSPHERE
ELECTRON COLLISIONS
ELECTRON-ION COLLISIONS
ELECTRON-MOLECULE COLLISIONS
EQUATIONS
F REGION
INSTABILITY
INSTABILITY GROWTH RATES
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONOSPHERE
KINETIC EQUATIONS
MOLECULE COLLISIONS
PLANETARY IONOSPHERES
PLASMA DENSITY
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
SPREAD F