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arXiv · 2507.11219

Recovery of hydrogen plasma at the sub-nanosecond timescale in a plasma-wakefield accelerator

R. Pompili·M. P. Anania·A. Biagioni·M. Carillo·E. Chiadroni·A. Cianchi·G. Costa·L. Crincoli·A. Del Dotto·M. Del Giorno·F. Demurtas·M. Ferrario·M. Galletti·A. Giribono·J. K. Jones·V. Lollo·T. Pacey·G. Parise·G. Di Pirro·S. Romeo·G. J. Silvi·V. Shpakov·F. Villa·A. Zigler
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Abstract

Plasma wakefield acceleration revolutionized the field of particle accelerators by generating gigavolt-per-centimeter fields. To compete with conventional radio-frequency (RF) accelerators, plasma technology must demonstrate operation at high repetition rates, with a recent research showing feasibility at megahertz levels using an Argon source that recovered after about 60 ns. Here we report about a proof-of-principle experiment that demonstrates the recovery of a Hydrogen plasma at the sub-nanosecond timescale. The result is obtained with a pump-and-probe setup and has been characterized for a wide range of plasma densities. We observed that large plasma densities reestablish their initial state soon after the injection of the pump beam (< 0.7 ns). Conversely, at lower densities we observe the formation of a local dense plasma channel affecting the probe beam dynamics even at long delay times (> 13 ns). The results are supported with numerical simulations and represent a step forward for the next-generation of compact high-repetition rate accelerators.

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R. Pompili, M. P. Anania, A. Biagioni, M. Carillo, E. Chiadroni, A. Cianchi, G. Costa, L. Crincoli, A. Del Dotto, M. Del Giorno, F. Demurtas, M. Ferrario, M. Galletti, A. Giribono, J. K. Jones, V. Lollo, T. Pacey, G. Parise, G. Di Pirro, S. Romeo, G. J. Silvi, V. Shpakov, F. Villa, A. Zigler. 2025-07-15. Recovery of hydrogen plasma at the sub-nanosecond timescale in a plasma-wakefield accelerator. https://doi.org/10.1038/s42005-024-01739-x

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