Analysis of the heating scenarios of the ion Bernstein wave (IBW) experiment in Frascati Tokamak Upgrade

Abstract

Ion Bernstein waves (IBWs) have been proposed as useful for heating and improving transport in tokamak plasmas. The experiments carried out so far have not provided a sufficient assessment of this concept, due to the occurrence of parasitic phenomena that caused poor reproducibility of IBW heating and confinement effects. An experiment on FTU has given the first test of IBW coupling to a tokamak plasma by a waveguide antenna utilized in place of the standard dipole antenna. In addition, the experiment operates at a high frequency that is expected to reduce the non-linear wave-plasma interaction at the edge. These phenomena were considered to be the cause of the lack of RF power penetration in the plasma bulk and of the production of impurity influx. The possible IBW experimental scenarios expected for the FTU plasma are described. To perform this analysis, quasi-linear and non-linear models are utilized for the wave propagation, damping and turbulence suppression suitable for transport barrier formation. As a result of this study, FTU is expected to be a useful facility for testing the IBW concept for advanced tokamaks.