Electron Holes in a Regularized Kappa Background

Fernando Haas; Horst Fichtner; Klaus Scherer

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arXiv · 2310.09081

Electron Holes in a Regularized Kappa Background

Fernando Haas·Horst Fichtner·Klaus Scherer

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Abstract

The pseudopotential method is used to derive electron hole structures in a suprathermal plasma having a regularized $\kappa$ probability distribution function background. The regularized character allows the exploration of small $\kappa$ values beyond the standard suprathermal case, for which $\kappa > 3/2$ 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 $\kappa \gg 1$ limit.

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Fernando Haas, Horst Fichtner, Klaus Scherer. 2023-10-13. Electron Holes in a Regularized Kappa Background. https://arxiv.org/abs/2310.09081

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