HELICON WAVE EXCITATION AND PROPAGATION IN A TOROIDAL HELIAC - EXPERIMENT AND THEORY

In this paper a comparison between theoretical calculations and experimental measurements of helicon wave coupling by a partial-turn shielded antenna in a toroidal heliac is presented. Despite the complicated heliac geometry, the wave dispersion, field profiles, and antenna radiation resistance are described well by a cylindrical uniform plasma theory. It also presents a simple formula relating the radiation resistance to the measured wave magnetic field per unit antenna current. Finally, the scaling of these results to the Heliac-1 (H-1) [Fusion Technol. 17, 123 (1990)]; a larger heliac now operating at the Australian National University (ANU), is discussed. © 1995 American Institute of Physics.