Nonlinear Interaction of Global MHD Modes in the Presence of Non-Ideal Effects

Summary form only given. In the presence of non-ideal effects global MHD modes excited due to development of interchange type instabilities can have both an imaginary part of frequency (purely growing modes), and finite real frequency in the excited wave spectrum. This in turn can lead to significant changes in the non-linear processes which are responsible for the spectral wave energy transfer, convective cell formation and anomalous plasma diffusion in such systems. The importance of localized low-frequency structures for the diffusion will be analyzed. The non-linear processes will be considered in the limit k _par = 0, where k_par is the wave vector along the external magnetic field. Simulation results related to non-linear cell formation by the electrostatic interchange modes in the presence of gravity will be presented. Possibility of excitation of nonlinear localized low-frequency structures during wire implosion experiments will be also discussed