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arXiv · 2109.01431

Beam-Plasma Dynamics in Finite-Length, Collisionless Inhomogeneous Systems

R. Mishra·R. Moulick·S. Adhikari·S. Marholm·A. J. Eklund·W. J. Miloch
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Abstract

This study investigates the streaming instability triggered by ion motion in a plasma system that is finite in length, collisionless, and inhomogeneous. Employing numerical simulations using Particle-In-Cell (PIC) techniques and kinetic equations, the study examines how inhomogeneity emerges from integrating a cold ion beam with a background plasma within a confined system. The findings suggest that steady ion flow can modify ion sound waves through acoustic reflections from system boundaries, leading to instability. Such phenomena are known to be a hydrodynamic effect. However, there are also signatures of the beam-driven ion sound instability where kinetic resonances play a pivotal role. The main objective is to understand the impact of a finite-length system on beam-plasma instability and to identify the wave modes supported in such configurations.

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R. Mishra, R. Moulick, S. Adhikari, S. Marholm, A. J. Eklund, W. J. Miloch. 2021-09-03. Beam-Plasma Dynamics in Finite-Length, Collisionless Inhomogeneous Systems. https://arxiv.org/abs/2109.01431

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