Experiments on Ion Cyclotron Waves

Abstract

Experiments have been performed on the generation of ion cyclotron waves and their propagation into a magnetic beach. The experiments were carried out on the B-66 machine, which is currently a magnetic mirror device. Studies of the production of neutrons have provided evidence for the absorption of the energy of these waves via ion cyclotron damping. Microwave phase-shift measurements have now been made, and the addition of electron density completes the list of parameters required for direct comparison of experimental and theoretical dispersion relations. The experimental data yield a smooth monotonic relation between density and frequency which is qualitatively similar to that predicted by theory. There are, however, unexplained quantitative differences. Wave propagation into the magnetic beach region was observed with a single turn rf magnetic probe. The variation of the amplitude of these waves in the magnetic beach is in qualitative agreement with the theory of ion cyclotron wave propagation and cyclotron damping.