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arXiv · 2409.20444

Long-Wavelength Limit of the Two-Fluid Euler-Poisson System

Emily Kelting·J. Douglas Wright
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Abstract

Plasma is a medium filled with free electrons and positive ions. Each particle acts as a conducting fluid with a single velocity and temperature when electromagnetic fields are present. This distinction between the roles played by electrons and ions is what we refer to as the two$-$fluid description of plasma. In this paper, we investigate the dynamics of these particles in both hot and cold plasma using a collisionless ''Euler-Poisson'' system. Employing analytical and computational techniques from differential equations, we show this system is governed by the dynamics of the Korteweg$-$de Vries (KdV) equation in the long$-$wavelength limit.

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Emily Kelting, J. Douglas Wright. 2024-09-30. Long-Wavelength Limit of the Two-Fluid Euler-Poisson System. https://arxiv.org/abs/2409.20444

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