Possibility that Anomalous Plasma Diffusion Depends on Geometric Factor

Turbulent diffusion coefficients for an assumed spectrum are derived using fluid equations, a crucial assumption being that the ion motion parallel to the magnetic field is hindered by the collision of ions with neutrals. The result shows that the turbulent diffusion coefficients depend on geometric factors, as well as on the level of fluctuations. This dependence on geometric factors may explain the experimentally observed difference in confinement times in different toroidal plasma confinement devices.