Status of the radiofrequency modelling of the WEST Ion Cyclotron Travelling Wave Array launcher

The design of an Ion Cyclotron Range of Frequency (ICRF) Travelling Wave Array (TWA) launcher is ongoing for the WEST tokamak. This type of launcher have several interesting properties compared to traditional in-port launchers and are well suited for future fusion power plants. The paper presents the latest results of radio-frequency modelling of the TWA launchers. The RF response in front of a realistic and representative WEST plasma has been calculated for several radial outer gaps. The reflected power of the TWA is lower than −20 dB on a more than 10 MHz frequency band. For the same coupled power to the plasma, the TWA launcher shows a drastic reduction of the near-fields, particularly on the antenna edge limiters. This reduction should reduce the sputtering of high-Z materials induced by RF sheaths.