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

Guilhem Dif-Pradalier (1) , P.H S Diamond (1) , Virginie Grandgirard (2) , Yanick Sarazin (2) , C S Abiteboul (2) , Xavier Garbet (2) , Philippe Ghendrih (2) , A. Strugarek (2) , S Ku (3) , C S Chang (3)

1 CASS - Center for Astrophysics and Space Sciences [La Jolla]
2 IRFM - Institut de Recherche sur la Fusion par confinement Magnétique
3 CIMS - Courant Institute of Mathematical Sciences [New York]

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.

Domaines: Science non linéaire [physics]; Physique des plasmas [physics.plasm-ph]

Guilhem Dif-Pradalier, P.H S Diamond, Virginie Grandgirard, Yanick Sarazin, C S Abiteboul, et al.. On the validity of the local diffusive paradigm in turbulent plasma transport. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2010, 82, pp.025401. ⟨10.1103/PhysRevE.82.025401⟩. ⟨cea-01468369⟩