Finding the Elusive E × B Staircase in Magnetized Plasmas

Guilhem Dif-Pradalier (1) , G Hornung (2) , Philippe Ghendrih (1) , Yanick Sarazin (1) , F Clairet (1) , L Vermare (3) , P H Diamond , J Abiteboul (4) , T Cartier-Michaud (1) , C Ehrlacher (1) , Daniel Estève (1) , Xavier Garbet (1) , Virginie Grandgirard (1) , Özgür D. Gürcan (3) , P Hennequin (3) , Y Kosuga (5) , Guillaume Latu (1) , P Maget (1) , Pierre Morel (3) , C Norscini (1) , R Sabot (1) , A. Storelli (3)

1 IRFM - Institut de Recherche sur la Fusion par confinement Magnétique
2 UGENT - Universiteit Gent = Ghent University
3 LPP - Laboratoire de Physique des Plasmas
4 IPP - Max-Planck-Institut für Plasmaphysik [Garching]
5 Kyushu University

Turbulence in hot magnetized plasmas is shown to generate permeable localized transport barriers that globally organize into the so-called "ExB staircase" [G. Dif-Pradalier et al., Phys. Rev. E, 82, 025401(R) (2010)]. Its domain of existence and dependence with key plasma parameters is discussed theoretically. Based on these predictions, staircases are observed experimentally in the Tore Supra tokamak by means of high-resolution fast-sweeping X-mode reflectometry. This observation strongly emphasizes the critical role of mesoscale self-organization in plasma turbulence and may have far-reaching consequences for turbulent transport models and their validation.

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

Guilhem Dif-Pradalier, G Hornung, Philippe Ghendrih, Yanick Sarazin, F Clairet, et al.. Finding the Elusive E × B Staircase in Magnetized Plasmas. Physical Review Letters, 2015, 114, pp.085004. ⟨10.1103/PhysRevLett.114.085004⟩. ⟨cea-01468384⟩