ION-CYCLOTRON RANGE OF FREQUENCY HEATING OF A DEUTERIUM-TRITIUM PLASMA VIA THE 2ND-HARMONIC TRITIUM CYCLOTRON-RESONANCE

Experiments have been performed on the TFTR to study rf wave heating of a D-T plasma by way of the second-harmonic tritium cyclotron resonance. The addition of tritium ions to a deuterium plasma allows for absorption of the rf waves at the tritium cyclotron harmonics and by electron damping of a mode converted ion Bernstein wave. Competing mechanisms include direct electron damping and damping at the fundamental cyclotron resonance of deuterium, alpha particles, and He-3 ions. The contribution of each is estimated from a series of plasma discharges where various plasma parameters are varied. The majority of the rf power is found to damp on the tritium ions.