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arXiv · 2602.05606

An approximate Kappa generator for particle simulations

Seiji Zenitani·Takayuki Umeda
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Abstract

A random number generator for the Kappa velocity distribution in particle simulations is proposed. Approximating the cumulative distribution function with the q-exponential function, an inverse transform procedure is constructed. The proposed method provides practically accurate results, in particular for k<4. It runs fast on graphics processing units (GPUs). The derivation, numerical validation, and relevance to GPU execution models are discussed.

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Seiji Zenitani, Takayuki Umeda. 2026-02-05. An approximate Kappa generator for particle simulations. https://doi.org/10.1186/s40623-026-02465-0

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