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arXiv · 2503.05686

First order non-instantaneous corrections in collisional kinetic alignment models

Laura Kanzler·Carmela Moschella·Christian Schmeiser
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Abstract

In this work the standard kinetic theory assumption of instantaneous collisions is lifted. As a continuation of of a previous paper by Kanzler, Schmeiser, and Tora [KRM, 2024], a model for higher order non-instantaneous alignment collisions is presented and studied in the asymptotic regime of short collision duration. A first order accurate approximative model is derived as a correction to the instantaneous limit. Rigorous results on its well-posedness and on the instantaneous limit are proven. The approximative model is a system of two equations. An equally accurate scalar approximation is suggested.

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Laura Kanzler, Carmela Moschella, Christian Schmeiser. 2025-03-07. First order non-instantaneous corrections in collisional kinetic alignment models. https://arxiv.org/abs/2503.05686

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