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arXiv · 2312.00969

Numerical Investigation of Non-equilibrium Electron Effects on the Collisional Ionization Rate in the Collisional-Radiative Model

M. S. Cho·H. -K. Chung·M. E. Foord·S. B. Libby·B. I. Cho
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Abstract

The interplay of kinetic electron physics and atomic processes in ultrashort laser-plasma interactions provides a comprehensive understanding of electron energy distribution's impact on plasma properties. Notably, non-equilibrium electrons play a vital role in collisional ionization, influencing ionization degrees and spectra. This paper introduces a computational model that integrates the physics of kinetic electrons and atomic processes, utilizing a Boltzmann equation for non-equilibrium electrons and a collisional-radiative model for atomic state populations. The model is used to investigate the influence of non-equilibrium electrons on collisional ionization rates and their effect on population distribution, as demonstrated by L. Young et al. (Nature, 2010). The study reveals significant non-equilibrium electron presence during XFEL-matter interactions, profoundly affecting collisional ionization rates in the gas plasma, thereby necessitating careful consideration of the Collisional-Radiative (CR) model applied to such systems.

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M. S. Cho, H. -K. Chung, M. E. Foord, S. B. Libby, B. I. Cho. 2023-12-01. Numerical Investigation of Non-equilibrium Electron Effects on the Collisional Ionization Rate in the Collisional-Radiative Model. https://arxiv.org/abs/2312.00969

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