Induced Scattering and Velocity Space Diffusion Due to Nonlinear Landau Damping of Electromagnetic and Electrostatic Waves in a Plasma

Abstract

The kinetic wave equation for nonlinear wave-particle scattering (nonlinear Landau damping) of electromagnetic and electrostatic waves in a homogeneous unmagnetized plasma and the velocity space diffusion equation which describes a distortion of a velocity distribution function are derived from Vlasov-Maxwell equations by perturbation theory. The nonlinear wave-particle coupling coefficient in the kinetic wave equation and the velocity space diffusion coefficient are expressed by four-order tensors which can be also applied to the cases in which two scattering waves are electrostatic or partially electrostatic. The conservation laws for total energy and momentum densities of waves and particles are confirmed, and the time evolutions for energy and momentum densities of particles are given by means of nonlinear wave-particle coupling coefficients.