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arXiv · 2204.10551

Compactness property of the linearized Boltzmann operator for a polyatomic gas undergoing resonant collisions

Thomas Borsoni·Laurent Boudin·Francesco Salvarani
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Abstract

In this paper, we investigate a compactness property of the linearized Boltzmann operator in the context of a polyatomic gas whose molecules undergo resonant collisions. The peculiar structure of resonant collision rules allows to tensorize the problem into a velocity-related one, neighbouring the monatomic case, and an internal energy-related one. Our analysis is based on a specific treatment of the contributions due to the internal energy of the molecules. We also propose a geometric variant of Grad's proof of the same compactness property in the monatomic case.

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Thomas Borsoni, Laurent Boudin, Francesco Salvarani. 2022-04-22. Compactness property of the linearized Boltzmann operator for a polyatomic gas undergoing resonant collisions. https://arxiv.org/abs/2204.10551

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