E×B staircases and barrier permeability in magnetised plasmas. (17th November 2016)

• Record Type: Journal Article
• Authors: Hornung, G.; Dif-Pradalier, G.; Clairet, F.; Sarazin, Y.; Sabot, R.; Hennequin, P.; Verdoolaege, G.
• Is Part Of: Nuclear fusion. Volume 57:Number 1(2017:Jan.)
• Publication Date: 2016-11-17
• Subjects: plasma transport -- plasma turbulence -- shear flows; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/0029-5515/57/1/014006
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: In-depth experimental characterisation of spontaneous shear flow patterning into a so-called E × B staircase—named after its planetary analogue—is shown in magnetised plasma turbulence, using ultrafast-sweeping reflectometry in the Tore Supra tokamak. Staircase signatures are found in a large variety of L-mode plasma conditions. Sensitivity to the dominant source of free energy is highlighted for the first time. A connection between staircase shear layer permeability and deviation from gyro-Bohm confinement scaling is strongly suggested, opening new routes to understanding confinement in drift-wave turbulence.