SPHERICAL STELLARATOR CONFIGURATION

A novel ultralow aspect ratio stellarator system that can be called a spherical stellarator (SS), in analogy with the spherical tokamak conc ept, is considered. The coil configuration of a simplest SS differs fr om that of a spherical tokamak by inclination of the external parts of the toroidal field coils. This system possesses many attractive prope rties including compact design and coil simplicity, good access to the plasma, closed vacuum flux surfaces with large enclosed volume, signi ficant external rotational transform, strong magnetic well, and simple divertor configuration.