Stability of Localised MHD Modes in Divertor Tokamaks – a picture of the H-mode

Nuclear Fusion | , Vol 26: pp. 1063

The paper examines the stability of a model divertor tokamak equilibrium to MHD ballooning and interchange modes. The combined effects of the magnetic separatrix and a finite edge current density can result in coalescence of the first and second stable regions. This leads to a picture of the H-mode in which the observed steep edge pressure gradients result from the modified ballooning stability properties.