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arXiv · 2007.03945

The $κ$-cookbook: a novel generalizing approach to unify $κ$-like distributions for plasma particle modeling

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

In the literature different so-called $κ$-distribution functions are discussed to fit and model the velocity (or energy) distributions of solar wind species, pickup ions or magnetospheric particles. Here we introduce a generalized (isotropic) $κ$-distribution as a "cookbook", which admits as special cases, or "recipes", all the other known versions of $κ$-models. A detailed analysis of the generalized distribution function is performed, providing general analytical expressions for the velocity moments, Debye length, and entropy, and pointing out a series of general requirements that plasma distribution functions should satisfy. From a contrasting analysis of the recipes found in the literature, we show that all of them lead to almost the same macroscopic parameters with a small standard deviation between them. However, one of these recipes called the regularized $κ$-distribution provides a functional alternative for macroscopic parameterization without any constraint for the power-law exponent $κ$.

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Klaus Scherer, Edin Husidic, Marian Lazar, Horst Fichtner. 2020-07-08. The $κ$-cookbook: a novel generalizing approach to unify $κ$-like distributions for plasma particle modeling. https://doi.org/10.1093/mnras%2Fstaa1969

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