Stationary equilibrium and diffusion in a toroidal plasma with helical magnetic field

A theoretical study of the equilibrium and diffusion in a stellarator field with the helical winding l =3 has been carried out. It is shown that a stationary equilibrium exists even when finite inertia and finite ion gyroradius effects are taken into account. The plasma loss flux consists of two parts; one is determined by the averaged magnetic field and the other is due to the perturbed components with helical structure of the electrostatic potential and of the density distribution. The latter term will become appreciable when a marked anisotropy in electron pressure presents.