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arXiv · 2007.02526

Sticky islands in stochastic webs and anomalous chaotic cross-field particle transport by ExB electron drift instability

D. Mandal·Y. Elskens·X. Leoncini·N. Lemoine·F. Doveil
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Abstract

The ExB electron drift instability, present in many plasma devices, is an important agent in cross-field particle transport. In presence of a resulting low frequency electrostatic wave, the motion of a charged particle becomes chaotic and generates a stochastic web in phase space. We define a scaling exponent to characterise transport in phase space and we show that the transport is anomalous, of super-diffusive type. Given the values of the model parameters, the trajectories stick to different kinds of islands in phase space, and their different sticking time power-law statistics generate successive regimes of the super-diffusive transport.

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D. Mandal, Y. Elskens, X. Leoncini, N. Lemoine, F. Doveil. 2020-07-06. Sticky islands in stochastic webs and anomalous chaotic cross-field particle transport by ExB electron drift instability. https://doi.org/10.1016/j.chaos.2021.110810

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