SPLITTING OF THE SPECTRA OF MHD PLASMA-OSCILLATIONS IN A RIPPLED MAGNETIC-FIELD

The perturbation theory is used to find the correction delta omega to the eigenfrequency introduced by a small ripple in an external magneti c field and to determine the electromagnetic fields of magnetohydrodyn amic oscillations of a rippled plasma column with a radially nonunifor m density profile under resonance conditions such that the period of t he fundamental mode of magnetohydrodynamic oscillations in the axial d irection is twice as large as the period of the rippled magnetic field . It is shown that the splitting of the eigenfrequency of such magneto hydrodynamic oscillations is a first-order effect in the small ripple amplitude epsilon (delta omega proportional to epsilon), whereas, in t he nonresonant case, this is a second-order effect (delta omega propor tional to epsilon(2)).