Ion-cyclotron heating experiments on the Heliotron-D

Ion-cylotron resonance heating experiments in the toroidal plasma of the Heliotron-D are described. The magnetic configuration used has a fairly strong helical inhomogeneity with a large rotational transform angle and shear. An appreciable ion temperature increase is observed from measurements of the Doppler line width of He-II at a 100 kW r.f. power level. A comparison study with other devices is described for a scaling of the ion-cyclotron resonance heating in present toroidal plasma.