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arXiv · 2108.01889

Plasma-wall transition and sheath formation

Giovanni Manfredi·Fabrice Valsaque
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Abstract

A review of the theoretical and computational aspects of plasma-wall transition is presented. The conditions for the existence of plasma sheaths in front of a solid surface are established. Various regimes are analyzed -collisionless and collisional. fluid and kinetic, with and without ionization. The partition of the plasma-wall transition into distinct regions (Debye sheath, quasineutral presheath. magnetic presheath, etc...) is also discussed. Applications to the theory of electrostatic probes are illustrated by means of a recently developed kinetic model. The influence of the probe on ion temperature measurements is studied in detail.

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Giovanni Manfredi, Fabrice Valsaque. 2021-08-04. Plasma-wall transition and sheath formation. https://arxiv.org/abs/2108.01889

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