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arXiv · 1912.09173

Weakly nonlinear ion sound waves in gravitational systems

P. Guio·H. L. Pecseli
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Abstract

Ion sound waves are studied in a plasma subject to gravitational field. Such systems are interesting by exhibiting a wave growth that is a result of energy flux conservation in inhomogeneous systems. The increasing wave amplitude gives rise to an enhanced interaction between waves and plasma particles that can be modeled by a modified Korteweg-de Vries equation. Analytical results are compared with numerical Particle-in-Cell simulations of the problem. Our code assumes isothermally Boltzmann distributed electrons while the ion component is treated as a collection of individual particles interacting through collective electric fields. Deviations from quasi neutrality are allowed for.

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P. Guio, H. L. Pecseli. 2019-12-19. Weakly nonlinear ion sound waves in gravitational systems. https://doi.org/10.1103/physreve.101.043210

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