Adiabatic nonlinear waves with trapped particles. III. Wave dynamics

Journal Article · Sun Jan 15 04:00:00 EST 2012 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3673065· OSTI ID:22043544

Dodin, I Y; Fisch, N J ^[1]

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1. Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States)

The evolution of adiabatic waves with autoresonant trapped particles is described within the Lagrangian model developed in Paper I, under the assumption that the action distribution of these particles is conserved, and, in particular, that their number within each wavelength is a fixed independent parameter of the problem. One-dimensional nonlinear Langmuir waves with deeply trapped electrons are addressed as a paradigmatic example. For a stationary wave, tunneling into overcritical plasma is explained from the standpoint of the action conservation theorem. For a nonstationary wave, qualitatively different regimes are realized depending on the initial parameter S, which is the ratio of the energy flux carried by trapped particles to that carried by passing particles. At S < 1/2, a wave is stable and exhibits group velocity splitting. At S > 1/2, the trapped-particle modulational instability (TPMI) develops, in contrast with the existing theories of the TPMI yet in agreement with the general sideband instability theory. Remarkably, these effects are not captured by the nonlinear Schroedinger equation, which is traditionally considered as a universal model of wave self-action but misses the trapped-particle oscillation-center inertia.

• OSTI ID: 22043544
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 1 Vol. 19; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DISTRIBUTION
INSTABILITY
LAGRANGIAN FUNCTION
MOMENT OF INERTIA
NONLINEAR PROBLEMS
ONE-DIMENSIONAL CALCULATIONS
OSCILLATIONS
PARTICLES
PLASMA
PLASMA WAVES
SCHROEDINGER EQUATION
SIMULATION
TRAPPED ELECTRONS
TRAPPING
TUNNEL EFFECT
WAVELENGTHS