Aa. Hussein et Wa. Scales, SIMULATION STUDIES OF PARAMETRIC DECAY PROCESSES ASSOCIATED WITH IONOSPHERIC STIMULATED RADIATION, Radio science, 32(5), 1997, pp. 2099-2107
Parametric instability processes are thought to produce stimulated ele
ctromagnetic emissions during ionospheric heating experiments. The phe
nomenon is primarily attributed to plasma turbulence excited by the hi
gh-frequency heater in the altitude region where the pump frequency om
ega(0) is near the plasma upper hybrid frequency omega(uh). In this st
udy, parametric instability processes thought to produce ionospheric s
timulated radiation are studied using electrostatic particle-in-cell s
imulation models. The emphasis in this work will be to consider the ex
citation and interactions between electrostatic waves generated by the
pump wave. The simulation plasma is driven with a uniform oscillating
electric field directed nearly perpendicular to the background geomag
netic field B to consider interactions when omega(uh) is near electron
cyclotron harmonics n Omega(ce). The pump frequency and amplitude are
varied to consider the effects on the simulation electric field power
spectrum. Also, the effect of varying the electron to ion temperature
ratio T-e/T-i is discussed and evaluated. The simulation results show
richly structured sidebands upshifted and downshifted above and below
the pump frequency, which are attributed to parametric instability pr
ocesses. The relationship between the simulation results, the theoreti
cal models, and the experimental spectrum are discussed.