Stimulated-Raman-scatter behavior in a relativistically hot plasma slab and an electromagnetic low-order pseudocavity

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

DOI:https://doi.org/10.1103/PHYSREVE.74.046407· OSTI ID:21072332

Ghizzo, A; Reveille, T; Bertrand, P; Albrecht-Marc, M ^[1]; Johnston, T W ^[2]

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1. L.P.M.I.A., Universite Henri Poincare, Boite Postale 239, 54506 Vandoeuvre les Nancy Cedex (France)
2. I.N.R.S. Energie, Materiaux et Telecommunications, Case Postal 1020, Varennes, Quebec, J3X1S2 (Canada)

Particle simulations on a flat-topped somewhat underdense (typically n{sub 0}/n{sub c}=0.6) plasma slab by Nikolic et al. [Phys. Rev. E 66, 036404 (2002)] were seen to give transient stimulated scattering behavior with frequency shift [{omega}{sub 0}-{omega}{sub s}({approx_equal}{omega}{sub p})] considerably less than the plasma frequency {omega}{sub p}. This has been linked to the electron acoustic wave (EAW) and the scattering was thus seen as another example of stimulated electron acoustic scattering inferred by Montgomery et al. [Phys. Rev. Lett. 87, 155001 (2001)] from experiments on low-density plasmas. Montgomery et al. had noted the difficulty of how one could have a very narrow observed scattering from a wave whose damping was at least initially very high. Our Vlasov-Maxwell simulations for such somewhat underdense (n{sub 0}/n{sub c}{>=}0.25) plasmas show that the simulation resonance was in fact determined by the beating of the pump with a new 'radiating pseudocavity' electromagnetic mode for the slab at a frequency close to {omega}{sub p} with relatively low loss. This allows the initial narrow-band excitation of the kinetic electrostatic electron nonlinear (KEEN) waves (the nonlinear 'cousins' of EAWs) at a well-defined frequency ({omega}{sub K}{approx_equal}{omega}{sub 0}-{omega}{sub p}<{omega}{sub p}) which is not necessarily the value given by the EAW dispersion relation. (The KEEN wave characteristics have been discussed by Afeyan et al. [33rd AAAC (2003), no. 238, IFSA 2003].) The consideration of such a mechanism is relevant to moderately underdense hot plasmas.

• OSTI ID: 21072332
• Journal Information: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics Journal Issue: 4 Vol. 74; ISSN PLEEE8; ISSN 1063-651X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BOLTZMANN-VLASOV EQUATION
DAMPING
DISPERSION RELATIONS
ELECTRON PLASMA WAVES
ELECTRONS
EXCITATION
HOT PLASMA
ION ACOUSTIC WAVES
LANGMUIR FREQUENCY
MAXWELL EQUATIONS
NONLINEAR PROBLEMS
PLASMA DENSITY
PLASMA INSTABILITY
PLASMA SIMULATION
RELATIVISTIC PLASMA
SCATTERING