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arXiv · 0901.0813

Fast growing instabilities for non-parallel flows

A. Bret
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Abstract

Unstable modes growing when two plasma shells cross over a background plasma at arbitrary angle $θ$, are investigated using a non-relativistic three cold fluids model. Parallel flows with $θ=0$ are slightly more unstable than anti-parallel ones with $θ=π$. The case $θ=π/2$ is as unstable as the $θ=0$ one, but the fastest growing modes are oblique. While the most unstable wave vector varies with orientation, its growth rate slightly evolves and there is no such thing as a stable configuration. A number of exact results can be derived, especially for the $θ=π/2$ case.

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A. Bret. 2009-01-07. Fast growing instabilities for non-parallel flows. https://doi.org/10.1016/j.physleta.2008.12.065

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