Neoclassical transport in high β tokamaks

Neoclassical, transport in high β large aspect ratio tokamaks is calculated. The variational method introduced by Rosenbluth, et al., is used to calculate the full Onsager matrix in the banana regime. These results are part of a continuing study of the high β large aspect ratio equilibria introduced in Cowley, et al. All the neoclassical coefficients are reduced from their nominal low β values by a factor (var-epsilon/q2β)1/2 II. This factor is the ratio of plasma volume in the boundary layer to the volume in the core. The fraction of trapped particles on a given flux surface (ft) is also reduced by this factor so that ∼ (var-epsilon/q2β)1/2. Special attention is given to the current equation, since this is thought to be relevant at low 3 and therefore may also be relevant at high β. The bootstrap current term is found to exceed the actual current by a factor of the square root of the aspect ratio