Effect of the radial electric field, induced by Alfven waves, on transport processes in tokamaks

Kinetic or slow Alfven waves, which appear in tokamak plasmas as a result of RF wave conversion, have small radial localization. For this reason, these waves are used here to create strongly sheared plasma flows at any point of the plasma minor radius and to obtain the locally reversed magnetic shear configuration. It is also demonstrated that Alfven waves may be a convenient trigger for formation of transport barriers in tokamaks. They can be used for suppressing plasma turbulence and squeezing ion banana and potato orbits. Estimates of the absorbed Alfven wave power, which is necessary to achieve these effects in some tokamaks, are about the level of the absorbed power in early completed experiments. The use of Alfven waves can also be helpful for self-organization processes in tokamaks. (author)