The effect of kinetic processes on Langmuir turbulence
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Kinetic processes are shown to be crucial in determining the saturation level of stimulated Raman scattering for regimes relevant to NOVA [Campbell et al., Fusion Technol. 21, 1344 (1992)] and the National Ignition Facility [Lindl, Phys. Plasmas 2, 3933 (1995)]. To investigate these kinetic effects, the Zakharov, quasilinear-Zakharov, and reduced-description particle-in-cell simulation models are compared in the test case of a uniformly driven plasma. Good agreement is observed between all three simulation methods for relatively low primary Langmuir wave numbers (k{sub 1}{lambda}{sub De}{approx}0.1) in weakly driven regimes. In the strongly driven case, quasilinear diffusion provides an important correction to the Landau damping rate, producing saturation levels in agreement with reduced-description particle-in-cell simulations, in contrast to pure Zakharov simulations, which overestimate the saturation significantly. At higher k{sub 1}{lambda}{sub De}{approx}0.25, both the quasilinear-Zakharov and pure Zakharov models fail. In this regime, the autocorrelation time of the Langmuir wave spectrum is much larger than the quasilinear diffusion time, causing the quasilinear diffusion approximation to break down. (c) 2000 American Institute of Physics.
- OSTI ID:
- 20216043
- Journal Information:
- Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 5 Vol. 7; ISSN PHPAEN; ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Langmuir turbulence in the auroral ionosphere: 2. Nonlinear theory and simulations
Observation of a Transition from Fluid to Kinetic Nonlinearities for Langmuir Waves Driven by Stimulated Raman Backscatter
Different k{lambda}{sub D} regimes for nonlinear effects on Langmuir waves
Journal Article
·
Thu Mar 31 23:00:00 EST 1994
· Journal of Geophysical Research
·
OSTI ID:121277
Observation of a Transition from Fluid to Kinetic Nonlinearities for Langmuir Waves Driven by Stimulated Raman Backscatter
Journal Article
·
Fri May 06 00:00:00 EDT 2005
· Physical Review Letters
·
OSTI ID:20696241
Different k{lambda}{sub D} regimes for nonlinear effects on Langmuir waves
Journal Article
·
Mon May 15 00:00:00 EDT 2006
· Physics of Plasmas
·
OSTI ID:20783124