Equilibrium of self-organized electron spiral toroids

Cold-fluid magnetohydrodynamics equilibrium equations are solved for an infinite aspect-ratio, electron spiral torus (EST). The electrons follow approximately azimuthal orbits outside an interior ion cloud. The ion mass is assumed finite, and both electrons and ions are assumed collisionless. It is found that self-organized solutions for the electron shell and the ions exist when the EST is immersed in a neutral gas. The ion flow velocity profile is not rigid rotor. Examples of two different electron densities are examined. In each example, solutions exist for neutral gas pressure p above a critical level pc and are independent of an applied axial magnetic field. For the low-density example, the critical neutral pressure corresponds to the value observed in experiments. The equilibrium ion rotational flow velocity and self-magnetic field scale as p1/2