Observations of local cavity resonances of fast Alfven waves

Local cavity resonances of fast wave propagation in a hydrogen-deuterium tokamak plasma have been investigated experimentally. The results demonstrate short damping lengths of the fast waves on the high field side of the hybrid layer, and the existence of a local cavity resonance on the low field side, even for a low hydrogen minority concentration (5%) in a deuterium plasma. The strong wave damping disappears when the hybrid layer is moved towards the edge of the plasma. (author)