title: Kinetic simulations of the self-focusing and dissipation of finite-width electron plasma waves.
abstract: Two-dimensional simulations, both Vlasov and particle-in-cell, are presented that show the evolution of the field and electron distribution of finite-width, nonlinear electron plasma waves. The intrinsically intertwined effects of self-focusing and dissipation of field energy caused by electron trapping are studied in simulated systems that are hundreds of wavelengths long in the transverse direction but only one wavelength long and periodic in the propagation direction. From various initial wave states, both the width at focus Δm relative to the initial width Δ0 and the maximum field amplitude at focus are shown to be a function of the growth rate of the transverse modulational instability γTPMI divided by the loss rate of field energy νE to electrons escaping the trapping region. With dissipation included, an amplitude threshold for self-focusing γTPMI/νE∼1 is found that supports the analysis of Rose [Phys. Plasmas 12, 012318 (2005)].
authors.affiliation: Department of Electrical Engineering, University of California Los Angeles, Los Angeles, California 90095, USA.
authors.forename: B J
authors.initials: BJ
authors.lastname: Winjum
authors.affiliation: Lawrence Livermore National Laboratory, P. O. Box 808, Livermore, California 94551, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Berger
authors.affiliation: Lawrence Livermore National Laboratory, P. O. Box 808, Livermore, California 94551, USA.
authors.forename: T
authors.initials: T
authors.lastname: Chapman
authors.affiliation: Lawrence Livermore National Laboratory, P. O. Box 808, Livermore, California 94551, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Banks
authors.affiliation: Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, Ecole Polytechnique Fédérale de Lausanne, CRPP-PPB, CH-1015 Lausanne, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Brunner