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arXiv · 0906.0481

Predicting PDF tails of flux in plasma sheath region

Johan Anderson·Eun-jin Kim
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Abstract

This letter provides the first prediction of the probability density function (PDF) of flux $R$ in plasma sheath sheath region in magnetic fusion devices which is characterized by dynamical equations with exponential non-linearities. By using a non-perturbative statistical theory (instantons), the PDF tails of first moment are shown to be modified Gumbel distribution which represents a frequency distribution of the extreme values of the ensemble. The non-Gaussian PDF tails that are enhanced over Gaussian predictions are the result of intermittency caused by short lived coherent structures (instantons).

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BibTeXRIS

Johan Anderson, Eun-jin Kim. 2009-12-02. Predicting PDF tails of flux in plasma sheath region. https://doi.org/10.1088/0741-3335%2F52%2F1%2F012001

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