Ion cyclotron absorption of a fast magnetoacoustic wave in a tokamak

Factors of ion cyclotron attenuation of short wave fast magnetoacoustic waves in a tokamak plasma have been determined in the case of main and multiple cyclotron resonances with provision for the effect of ion rotation over small azimuth due to their motion along magnetic force lines. It is shown that attenuation factor does not depend on a longitudinal wave number and rotational transformation and is determined only with values of ratio epsilonsub(t)=r/R and frequency detuning Δω=ω-n anti ωsub(Bi) (R-large radius of torus, r-radius of magnetic surface, anti ωsub(Bi)-mean value of cyclotron frequency on this surface). Attenuation factors in the case of multiple resonances and main resonance for impurity ions of low concentrations coincide and in the case of main resonance for a basic group of ions-considerably exceed their values calculated using tensor of dielectric constant of a plasma averaged by magnetic surface