FORMATION OF EDGE AND INTERNAL TRANSPORT BARRIERS IN TOKAMAKS BY ALFVEN WAVES

It is demonstrated that Alfven waves may be the convenient trigger for the formation of transport barriers in tokamaks. Kinetic or slow Alfv en waves, which appear in the tokamak plasma as a result of the rf wav e's conversion, have small radial localizations. It is proposed that t hese waves can be used to create strongly sheared plasma flows at any point of the plasma minor radius, to suppress the plasma turbulence an d to obtain the locally reversed magnetic shear configuration. Estimat ions concerning the absorbed power of Alfven waves, which are necessar y to suppress the plasma turbulence in some tokamaks, are about the le vel of absorbed power to be used in early fulfilled experiments. This method can assist the achievement of self-organization processes in to kamaks. (C) 1998 American Institute of Physics.