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Abstract. Fokker-Planck coefficients specifying diffusion and convection transport processes for charged fusion products and NBI ions in tokamaks with weak TF ripples are derived in the COM space describing the collisional ripple transport processes of fast ions, both in the moderate and in the high energy range. The collisional diffusion coefficient of toroidally trapped ions which are in resonance with the TF ripple perturbations (so-called superbananas) is shown to exhibit only a weak dependence on the ripple magnitude and, further, to reach a maximum in the medium collisionality regime where the bounce frequency of superbananas is close to the effective collision frequency. This maximum appears in the energy range from a few tens of kEV to a few hundreds of keV and may exceed the well-known Boozer- ripple plateau diffusion in the case of weak ripples. The radial convection of superbananas induced by slowing down is shown also to exceed the corresponding convection of bananas. The collisional superbanana transport is supposed to be responsible for the enhanced NBI ion loss observed in the intermediate energy range and, hence, should be essentially embodied into any modeling of charged fusion products at energies E < 1MeV.
IAEA 2001
