Nonlinear Landau damping in nonextensive statistics

Journal Article · Fri Jul 15 04:00:00 EDT 2005 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.1947967· OSTI ID:20764370

Valentini, Francesco ^[1]

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1. Universita della Calabria, Dipartimento di Fisica and Istituto Nazionale di Fisica della Materia, Unita di Cosenza, I-87030 Arcavacata di Rende (Italy)

The evolution of electrostatic waves, in unmagnetized collisionless plasmas, is numerically investigated by using a semi-Lagrangian Vlasov-Poisson code, in the fully nonlinear regime and in the context of the nonextensive statistics proposed by Tsallis [C. Tsallis, J. Stat. Phys. 52, 479 (1988)]. The effect of the Landau damping saturation, due to the nonlinear wave-particle interaction, is analyzed as a function of different values of the nonextensive parameter q, which quantifies the degree of nonextensivity of the system. A preliminary linear study is performed in order to compare the analytical results for the frequency and the damping rate of the electric oscillations, with the quantities obtained from the numerical simulations. In the nonlinear regime, the time evolution of the electric field amplitude shows how the non-Maxwellian shape of the equilibrium distribution function drastically modifies the energy exchange between wave and resonant particles and determines the saturation level of the electric field amplitude, in the long-time oscillating regime. A broad spectrum for the electrostatic oscillations is obtained in the case of the initial distribution functions with q<1, while in the case q>1 just a monochromatic component is visible.

• OSTI ID: 20764370
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 7 Vol. 12; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
AMPLITUDES
BEAM-PLASMA SYSTEMS
BOLTZMANN-VLASOV EQUATION
CHARGED-PARTICLE TRANSPORT
COLLISIONLESS PLASMA
COMPARATIVE EVALUATIONS
DISTRIBUTION FUNCTIONS
ELECTRIC FIELDS
ENERGY TRANSFER
LAGRANGIAN FUNCTION
LANDAU DAMPING
MONOCHROMATIC RADIATION
NONLINEAR PROBLEMS
OSCILLATIONS
PLASMA SIMULATION
PLASMA WAVES
POISSON EQUATION
STATISTICS
THERMODYNAMICS