THE SPECTRUM OF MHD FLOWS ABOUT X POINTS

A recently proposed method to calculate the spectrum of linear, incomp ressible, unbounded plasma flows is applied to magnetohydrodynamic flo ws about X points. The method transforms the two-dimensional spectral problem in physical space into a one-dimensional problem in Fourier sp ace. The latter problem is far easier to solve. application of this me thod to X-point plasma flows results in two kinds of essential spectra . One kind corresponds to stable perturbations and the other one to pe rturbations that become overstable whenever the square of the poloidal Alfven Mach number becomes larger than 1. Apart from these two spectr a, no other spectral values were found.