Global Alfven mode excitation in a stellarator

Experimental and theoretical studies on Alfven plasma heating in tokamaks led to revealing regimes with high energy input efficiency due to the excitation of high-Q resonances of ''global'' Alfven modes. Frequencies of such resonances are close to the lower boundary of the Alfven continuum and a longitudinal current flow in the plasma is decisive for their existence. In the present paper, the excitation of Alfven modes and the effect of spatial spectra of generated fields upon the absorption zona localization are studied. An opportunity to generate high-Q resonance of the ''global'' Alfven mode in l=3 stellarator is found. 5 refs, 5 figs