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arXiv · 1906.01406

Moments of the anisotropic regularized $κ$-distributions

Klaus Scherer·Marian Lazar·Edin Husidic·Horst Fichtner
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Abstract

For collisionless (or collision-poor) plasma populations which are well described by the $κ$-distribution functions (also known as the Kappa or Lorentzian power-laws) a macroscopic interpretation has remained largely questionable, especially because of the diverging moments of these distributions. Recently significant progress has been made by introducing a generic regularization for the isotropic $κ$-distribution, which resolves this critical limitation. Regularization is here applied to the anisotropic forms of $κ$-distributions, commonly used to describe temperature anisotropies, and skewed or drifting distributions of beam-plasma systems. These regularized distributions admit non-diverging moments which are provided for all positive $κ$, opening promising perspectives for a macroscopic (fluid-like) characterization of non-ideal plasmas.

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Klaus Scherer, Marian Lazar, Edin Husidic, Horst Fichtner. 2019-07-10. Moments of the anisotropic regularized $κ$-distributions. https://doi.org/10.3847/1538-4357%2Fab1ea1

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