Theory of High Power Cyclotron Resonance Heating in Non-Uniform Magnetic Field

摘要

Energy absorption of a plasma due to cyclotron harmonic resonance is evaluated analytically and by a simulation. In the calculation an orbit modification of cyclotron motion of particles is fully taken into account. It is found that the absorption for the fundamental harmonic resonance (m=1) is depressed from that of the conventional linear approximation while the absorptions for m less than or greater than 2 are enhanced, where m is the harmonic number. The enhancement is significant when kp sub t is much less than 1 (K the perpendicular wave number and p sub the gyroradius of a thermal particle) and when the interaction time between the plasma particles and the wave exceeds a critical value that is obtainable analytically. For all m and kp sub t, there appear peaks or saturations in the absorption. The second harmonic ion cyclotron resonance heating experiment in the Princeton Large Tokamak is discussed in terms of this theory.