A numerical study on plasma acceleration processes with ion dynamics at the sub-nanosecond timescale

G. Parise; A. Cianchi; M. Galletti; F. Guglietta; R. Pompili; A. R. Rossi; M. Sbragaglia; D. Simeoni

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arXiv · 2602.03754

A numerical study on plasma acceleration processes with ion dynamics at the sub-nanosecond timescale

G. Parise·A. Cianchi·M. Galletti·F. Guglietta·R. Pompili·A. R. Rossi·M. Sbragaglia·D. Simeoni

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Abstract

Plasma wakefield acceleration is a groundbreaking technique for accelerating particles, capable of sustaining gigavolt-per-meter accelerating fields. Understanding the physical mechanisms governing the recovery of plasma accelerating properties over time is essential for successfully achieving high-repetition-rate plasma acceleration, a key requirement for applicability in both research and commercial settings. In this paper, we present numerical simulations of the early-stage plasma evolution based on the parameters of the SPARC_LAB hydrogen plasma recovery time experiment (Pompili et al., Comm. Phys. 7, 241 (2024)), employing spatially resolved Particle-in-Cell and fluid models. The experiment reports on a non-monotonic dependence of the plasma recovery time on the initial plasma density, an effect for which ion motion has been invoked as a contributing factor. The simulations presented here provide further insight into the role of ion dynamics in shaping this behavior. Furthermore, comparing Particle-in-Cell and fluid approaches allows us to assess the quality of fluid models for describing this class of plasma dynamics.

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G. Parise, A. Cianchi, M. Galletti, F. Guglietta, R. Pompili, A. R. Rossi, M. Sbragaglia, D. Simeoni. 2026-02-03. A numerical study on plasma acceleration processes with ion dynamics at the sub-nanosecond timescale. https://arxiv.org/abs/2602.03754

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