Analytic stability criteria for edge MHD oscillations in high performance ELM free tokamak regimes. (8th November 2017)

• Record Type: Journal Article
• Authors: Brunetti, D.; Graves, J.P.; Lazzaro, E.; Mariani, A.; Nowak, S.; Cooper, W.A.; Wahlberg, C.
• Is Part Of: Nuclear fusion. Volume 58:Number 1(2018:Jan.)
• Publication Date: 2017-11-08
• Subjects: magnetohydrodynamics -- tokamak -- infernal mode -- edge harmonic oscillations; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/1741-4326/aa9456
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: A new dispersion relation, and associated stability criteria, is derived for low- n external kink and infernal modes, and is applied to modelling the stability properties of quiescent H-mode like regimes. The analysis, performed in toroidal geometry with large edge pressure gradients associated with a local flattening of the safety factor, includes a pedestal, sheared toroidal rotation and a vacuum region separating the plasma from an ideal metallic wall. The external kink-infernal modes found here exhibit similarities with experimentally observed edge harmonic oscillations.