On Turbulence in magnetic Fusion Devices and its Suppression
A brief review of the properties of turbulence in magnetic fusion devices will be given. Namely, it is shown that intermittency in the so-called scrape-off layer is caused by large events having radial velocities 1/10 of the ion sound speed. It will be followed by discussing the universality of turbulence measured on many different magnetic devices. The statistical properties of the fluctuations, when the plasma transits into a high-confinement using neutral beam injection, are then compared to a low-confinement mode regime. It is found, to our surprise, that turbulence is not affected at all by this transition. However, when using wave heating, namely the ion cyclotron resonance heating, it is shown that the SOL turbulence is greatly modified and the radial transport across the separatrix is decreased. The large-scale intermittent structures are suppressed as well as the edge-localized modes induced transport.