Simulation of Propagation and Absorption of Fast Magnetosonic Waves Excited in Plasma of the L-2M Stellarator

A code has been developed for simulating the propagation and absorption of fast magnetosonic (FMS) waves excited in plasmas of controlled-fusion facilities. The longitudinal and azimuthal wavenumbers of an FMS wave propagating in a deuterium plasma with parameters characteristic of the ohmic-heating regime in the L-2M stellarator have been calculated. The wave frequency corresponds to the second harmonic of the ion cyclotron frequency of deuterium. The model of cold collisionless cylindrical plasma is used. The FMS wave absorption by ions and electrons has been calculated. It is shown that, for the second harmonic of the ion cyclotron frequency, 79% of the FMS wave power will be absorbed by ions. Therefore, in deuterium plasma, for efficient current drive using FMS waves, it is necessary either to use higher harmonics of the ion cyclotron frequency or to search for alternative mechanisms of FMS wave absorption by electrons, e.g., the mode conversion current drive method.