Linear and non-linear calculations of the tearing mode

The application of a two-dimensional, nonlinear MHD computer code to the tearing mode is described. For the case of the sheet pinch, linear growth rates are obtained. In addition, the linear and nonlinear behavior of the mode for the case when two singular surfaces are in close proximity is studied. For this double tearing mode, one finds that the linear growth rate is greatly enhanced over that of the single tearing mode. The mode is followed into the nonlinear regime and one finds it results in magnetic field configurations which could lead to enhanced diffusion. It was found that approximately ten percent of the energy released goes into kinetic energy