Asymptotic evolution of nonlinear Landau damping

Abstract

The long-time evolution of longitudinal perturbations in a spatially uniform collisionless plasma is studied. It is found that when the wavelength of the initially excited mode is equal to the simulation length, the numerical results agree with the analytical analysis. In addition, the numerical results agree with the analytical evaluated asymptotic electric field amplitude. The long-time evolution of a finite-amplitude electric field is given by a superposition of two counterpropagating `averaged' Bernstein-Greene-Kruskal (BGK) waves.