Physics of the L-H Transition and Type III-ELMs Phenomena (Scaling Properties and Dimensionless Analysis)

The stability theory of Alfven drift-waves shows that with increasing plasma pressure electron drift waves become strongly coupled with Alfven waves thus damping radial perturbations. The Alfven drift turbulence suppression at the plasma edge was suggested as a triggering mechanism for the L to H transition [1]. After the transition the resistive interchange in-stability emerges as a dominant phenomenon which reveals itself in the form of Type III ELMs. Magnetic flutter provides the resistive driver for the interchange instability and, together with the stability condition caused by the electric shear stabilisation, creates the right dependence of the marginal temperature on density and other plasma parameters seen in experiments.