PHYSICS CONSIDERATIONS ON PLASMA TRANSPORT

Aspects of the scaling of anomalous thermal diffusivities are discussed, particularly with respect to rho*, nu* and P. The ability of a number of transport models (drift wave, magnetic island and MHD) to lead to the experimentally observed scalings are discussed. Their capacity to explain a. variety of improved confinement regimes (H, VK, high beta(p) and low magnetic shear) is also briefly considered.