Stability of a Plasma Torus against Disturbances not Dependent on the Azimuth

Perturbations of a plasma torus which are independent of azimuth are not covered by the general theory. A method for treating these special modes is presented, uniqueness theorems proved, and a rapidly converging numerical scheme for computation is given. It is also shown that these modes have the same behavior in a torus of infinite aspect ratio as do the corresponding ones in a cylinder; therefore the infinitely thin torus is stable against these modes.