On the validity of the local diffusive paradigm in turbulent plasma transport

Phys Rev E Stat Nonlin Soft Matter Phys. 2010 Aug;82(2 Pt 2):025401. doi: 10.1103/PhysRevE.82.025401. Epub 2010 Aug 3.

Abstract

A systematic, constructive and self-consistent procedure to quantify nonlocal, nondiffusive action at a distance in plasma turbulence is exposed and applied to turbulent heat fluxes computed from the state-of-the-art full- f, flux-driven gyrokinetic GYSELA and XGC1 codes. A striking commonality is found: heat transport below a dynamically selected mesoscale has the structure of a Lévy distribution, is strongly nonlocal, nondiffusive, scale-free, and avalanche mediated; at larger scales, we report the observation of a self-organized flow structure which we call the " E × B staircase" after its planetary analog.