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arXiv · 2510.11890

Loading non-Maxwellian Velocity Distributions in Particle Simulations

Seiji Zenitani·Shunsuke Usami·Shuichi Matsukiyo
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Abstract

Numerical procedures for generating non-Maxwellian velocity distributions in particle simulations are presented. First, Monte Carlo methods for an $(r,q)$ distribution that generalizes flattop and kappa distributions are discussed. Then, two rejection methods for the regularized kappa distribution are presented, followed by a comparison in the $\kappa$ space. A simple recipe is proposed for the subtracted kappa distribution. Properties and numerical recipes for the ring and shell distributions with a finite Gaussian width are discussed. The ring and shell Maxwellians are further introduced as alternatives to the ring and shell distributions. Finally, methods for the super-Gaussian and the filled-shell distributions are presented.

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Seiji Zenitani, Shunsuke Usami, Shuichi Matsukiyo. 2025-10-13. Loading non-Maxwellian Velocity Distributions in Particle Simulations. https://doi.org/10.1029/2025ja034669

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