Theoretical Research on Super Neoclassical Transport and Global Transport

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Super neoclassical transport, which does not belong to the standard neoclassical transport, and related global transport are studied. Main results are as follows ; (1) A d f Monte Carlo simulation code to study neoclassical transport including finite banana orbit width effects "FORTEC" has been completed. In "FORTEC", a new method of two weighting has been proposed. Secondly, a new precise collision model to conserve momentum and energy has been considered. Thirdly, the radial electric field can be calculated so as to vanish the ion-ion collision induced particle flux. The effects of finite orbits of trapped particles are exactly included in "FORTEC" and hence it can simulate global transport. Many fruitful results have been obtained for transport near the magnetic axis, transport with steep density gradient, and associated radial electric field. (2) A Lagrangian formulation using constants of motion has been completed for analytical study of transport near the axis In which particle orbits are completely different from standard ones. The Lagrangian formulation Includes the non-locality of transport. The analytical results agree well with those of simulations. (3) Global transport has been studied in the plasma with perturbed magnetic fields. In the presence of magnetic islands and their overlapping, cumulant and auto-correlation are calculated. It is found that in almost all cases the radial diffusions are non-uniform, non-Gaussian, non-stationally, non-Markovian, and sub-diffusive. This means that transport is non-local or global in the presence of small magnetic perturbations.