Showing papers by "Barbara F. Lasinski published in 1997"
TL;DR: In this paper, a Boltzmann fluid model is used for the electrons and a particle-in-cell representation for the ions to simulate ion wave phenomena efficiently, while retaining a fully kinetic representation of the ions, and a new dispersion relation is derived describing the parametric instability of ion waves, evidence for which is observed in their simulations.
Abstract: One- and two-dimensional simulations and supporting analysis of nonlinear ion acoustic waves as might be associated with the saturation of stimulated Brillouin backscattering (SBBS) are presented. To simulate ion wave phenomena efficiently, while retaining a fully kinetic representation of the ions, a Boltzmann fluid model is used for the electrons, and a particle-in-cell representation is used for the ions. Poisson’s equation is solved in order to retain space-charge effects. We derive a new dispersion relation describing the parametric instability of ion waves, evidence for which is observed in our simulations. One- and two-dimensional simulations of plasma with either initially cold or warm ions (and multi-species ions) exhibit a complex interplay of phenomena that influence the time evolution and relaxation of the amplitude of the excited ion wave: ion trapping, wave steepening, acceleration, heating and tail formation in the ion velocity distribution, parametric decay into longer wavelength ion waves...
93 citations
TL;DR: Kirkwood et al. as discussed by the authors found that ion waves can be stimulated by a single laser beam by the process of Stimulated Brillouin Scattering (SBS) in which an ion acoustic and a scattered electromagnetic wave grow from noise.
Abstract: The laser and plasma conditions expected in ignition experiments using indirect drive inertial confinement have been studied experimentally. It has been found that there are at least three ways in which ion waves can be stimulated in these plasmas and have significant effect on the energy balance and distribution in the target. First ion waves can be stimulated by a single laser beam by the process of Stimulated Brillouin Scattering (SBS) in which an ion acoustic and a scattered electromagnetic wave grow from noise. Second, in a plasma where more than one beam intersect, ion waves can be excited at the `beat` frequency and wave number of the intersecting beams, causing the side scatter instability to be seeded, and substantial energy to be transferred between the beams [R. K. Kirkwood et. al. Phys. Re0319v. Lett. 76, 2065 (1996)]. And third, ion waves may be stimulated by the decay of electron plasma waves produced by Stimulated Raman Scattering (SRS), thereby inhibiting the SRS process [R. K. Kirkwood et. al. Phys. Rev. Lett. 77, 2706 (1996)].
29 citations