Electron Holes in a Regularized Kappa Background

Abstract

Abstract. The pseudopotential method is used to derive electron hole structures in a suprathermal plasma having a regularized κ probability distribution function background. The regularized character allows the exploration of small κ values beyond the standard suprathermal case, for which κ > 3/2 is a necessary condition. We have found the nonlinear dispersion relation yielding the amplitude of the electrostatic potential in terms of the remaining parameters, in particular the drift velocity, the wavenumber and the spectral index. Periodic, solitary wave, drifting and non-drifting solutions have been identified. In the linear limit, the dispersion relation yields generalized Langmuir and electron acoustic plasma modes. Standard electron hole structures are regained in the κ ≫ 1 limit.

On the Evolution Equations of Nonlinearly Permissible, Coherent Hole Structures Propagating Persistently in Collisionless Plasmas

“…Mathematical and background plasma aspects related to the S-equation have been treated in a number of papers ( [32][33][34][35] ). The pseudo-potential method was used to derive the electron hole stucture in a superthermal plasma having a 𝜅 distribution with singularities in [36], and a regularized 𝜅 distribution in [37], the latter of which presenting an illustration of the Schamel distribution.…”