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arXiv · 1805.11220

How it cramps the flow: three regimes for the saturation of parallel ion-beam instabilities

Martin S. Weidl·Dan Winske·Christoph Niemann
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Abstract

Motivated by recent advances in laboratory experiments on parallel ion-beam instabilities, we present a theoretical framework for and simulations of their evolution towards shock formation and Fermi acceleration. After reviewing the theory of beam instabilities with a focus on the so-called nonresonant or Bell instability, which we show to be due to the gyromotion of background ions, we contrast the saturation of three parameter regimes: (I) the left-handed "nonresonant" regime, (II) the right-handed beam-gyroresonant regime, (III) the balanced, mixed-turbulence regime.

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Martin S. Weidl, Dan Winske, Christoph Niemann. 2018-05-29. How it cramps the flow: three regimes for the saturation of parallel ion-beam instabilities. https://doi.org/10.3847/1538-4357%2Fab0462

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