Neoclassical transport for the shaped tokamak with X point is investigated using Hamiltonian formalism. For a set of Soloveev’s configurations, the neoclassical diffusion coefficient is rigorously derived for the plateau regime which is inversely proportional to the connection length. When an X point appears on plasma boundary, the diffusion coefficient is greatly reduced by a much longer connection length compared with a circular cross-section plasma. Since the formalism is not limited for aspect ratio, for A = 1.3, it may be valid in a very narrow range of collisionality, 0.8 < V*i < 1.0, at / o = 0.95. In the range of collisionality, the detrapping rate is very high.
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