Ionospheric modification and parametric instabilities

Journal Article · Thu Feb 01 04:00:00 EST 1979 · Rev. Geophys. Space Phys.; (United States)

DOI:https://doi.org/10.1029/RG017i001p00135· OSTI ID:6463590

Fejer, J A

Thresholds and linear growth rates for stimulated Brillouin and Raman scattering and for the parametric decay instability are derived by using arguments of energy transfer. For this purpose an expression for the ponderomotive force is derived. Conditions under which the partial pressure force due to differential dissipation exceeds the ponderomotive force are also discussed. Stimulated Brillouin and Raman scattering are weakly excited by existing incoherent backscatter radars. The parametric decay instability is strongly excited in ionospheric heating experiments. Saturation theories of the parametric decay instability are therefore described. After a brief discussion of the purely growing instability the effect of using several pumps is discussed as well as the effects of inhomogenicity. Turning to detailed theories of ionospheric heating, artificial spread F is discussed in terms of a purely growing instability where the nonlinearity is due to dissipation. Field-aligned short-scale striations are explained in terms of dissipation of the parametrically excited Langmuir waves (plasma oscillations): they might be further amplified by an explosive instability (except the magnetic equator). Broadband absorption is probably responsible for the 'overshoot' effect: the initially observed level of parametrically excited Langmuir waves is much higher than the steady state level.

• Research Organization: Max-Planck-Institute fuer Aeronomie, 3411 Katlenburg-Lindau 3, Federal Republic of Germany
• OSTI ID: 6463590
• Journal Information: Rev. Geophys. Space Phys.; (United States), Journal Name: Rev. Geophys. Space Phys.; (United States) Vol. 17:1; ISSN RGPSB
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BRILLOUIN EFFECT
COHERENT SCATTERING
DATA
DATA FORMS
DOCUMENT TYPES
EARTH ATMOSPHERE
F REGION
HEATING
INFORMATION
INSTABILITY
INSTABILITY GROWTH RATES
IONOSPHERE
ISOLATED VALUES
NUMERICAL DATA
PARAMETRIC INSTABILITIES
PLANETARY IONOSPHERES
PLASMA HEATING
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA WAVES
RAMAN EFFECT
REVIEWS
SCATTERING
SPREAD F
STRIATIONS
THEORETICAL DATA