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arXiv · 2603.18715

Quantum Kinetics of Fast-Electron Inelastic Collisions in Partially-Ionized Plasmas

Yeongsun Lee·Pavel Aleynikov·Jong-Kyu Park
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Abstract

Fast electrons in partially ionized plasmas lose energy through inelastic collisions with bound electrons. While the mean energy loss is well described by stopping-power theory, fluctuations associated with discrete excitation and ionization events produce energy straggling and an additional longitudinal diffusion in momentum space. We incorporate this effect into fast-electron kinetics through a derived Fokker-Planck operator whose coefficients are obtained from ab initio quantum many-body simulations. We demonstrate that neglecting inelastic energy diffusion in partially ionized D-Ar plasmas can underestimate primary runaway-electron generation by several orders of magnitude.

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Yeongsun Lee, Pavel Aleynikov, Jong-Kyu Park. 2026-03-19. Quantum Kinetics of Fast-Electron Inelastic Collisions in Partially-Ionized Plasmas. https://arxiv.org/abs/2603.18715

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