Spectral stability of Alfven filament configurations

The two-fluid plasma equations that describe nonlinear Alfven perturbations have singular solutions in the form of current-vortex filaments. These filaments are analogous to point vortices in ideal hydrodynamics and geostrophic fluids. In this work the spectral (linear) stability of current-vortex filament configurations is analyzed and compared with the results obtained for point vortices in ideal hydrodynamics and the Charney-Hasegawa-Mima equation. We consider single rows, double rows-von Karman streets-and single and double rings of vortices. In all cases the stability picture for the current-vortex filaments is remarkably different from that of the other two models, which can be recovered as limiting cases of the two-fluid Alfven model. New regions of perturbations against which the system is stable are identified and the dependence on physical parameters is described. (C) 2000 American Institute of Physics. [S1070-664X(00)01606-2].