Investigation of stabilization mechanisms of global MHD instabilities in z-pinches

Abstract

Summary form only given, as follows. A systematic study of the linear stage of shear flow stabilization of z-pinches, based on a Hall MHD model with an equilibrium containing shear flow and axial magnetic field, is being performed. Shear flow and axial magnetic field can strongly influence the development of the instabilities. A general set of equations permitting evaluation of the combined effect of shear flow and axial magnetic field on the development of the m=0 sausage and m=1 kink instabilities is being investigated. The development in time of an initial density perturbation is followed numerically until it converges to the fastest growing eigenfunction. Linear growth rates as a function of axial wavenumber (k) are obtained for a wide range of parameters. The Hall term plays a destabilizing role and its inclusion into the model leads to the increase of the instability growth rate. The linear theory results were found to be in agreement with the instability growth observed in MHRDR computer simulations.