Analysis of the Tore Supra ICRF antenna with TOPICA

The Tore Supra (CEA) antenna for the ion cyclotron range of frequencies (ICRF) is a so-called resonant double loop antenna with internal matching capacitors. The required capacitance range is crucial in antenna and the tuning-and-matching network design. The capacitance value for a given discharge is also important for antenna operation. We discuss a method to accurately predict the tuning capacitance values in the presence of plasma operation, and for efficiently accounting for the capacitors in the performance analysis. The presented method relies on the use of the TOPICA code, a numerical suite developed for prediction and analysis of modern ICRF antenna systems; it is able to handle antennas with a realistic 3D geometry and an accurate 1D plasma model. Very good agreement with the experimental capacitance values is found using TOPICA, providing further experimental validation of the computational algorithm and physics model.