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arXiv · 2606.12127

Ionization-Induced Electrostatic Hose Instability in Electron-Beam-Sustained Plasmas

Jia-Hong Chen·Yi Yu·Jian Chen·Zhi-Bin Wang
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Abstract

We report the discovery of a previously unrecognized electrostatic hose instability in electron-beam-sustained plasmas, driven by the coupling between the electron beam centroid and the plasma generated via the beam-impact ionization. Unlike the conventional hose instability of relativistic beams propagating in underdense plasmas, this instability requires only ionization-capable electron beams readily produced by common emission processes and sheath acceleration, indicating broad relevance across various discharges. A linear theory is developed to predict the hosing frequency and growth rate, and particle-in-cell/Monte Carlo simulations confirm both the onset of instability and the theoretical predictions.

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Jia-Hong Chen, Yi Yu, Jian Chen, Zhi-Bin Wang. 2026-06-10. Ionization-Induced Electrostatic Hose Instability in Electron-Beam-Sustained Plasmas. https://arxiv.org/abs/2606.12127

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