Studies on Slowing down of Energetic Ions and Transport Coefficients by Makokot

摘要

Numerous numerical models have been proposed for studying the slowing down of energetic ions. Firstly the FOKKER-PLANCK codes study the velocity relaxation of fast ions distribution function without radial diffusion/CORDEY and CORE 1974, FOWLER et al 1976, DNESTROVSKI et al. 1977/. An important improvement have been carried out by averaging the collision operator along magnetic surfaces and including the effects of trapped particles. Secondly the MONTE-CARLO codes (DEI-CAS and MARTY 1974, LISTER 1976) treat the exact particles orbits but are very time consuming. In order to obtain the power deposited on magnetic surfaces, our starting point will be the bounce-averaged FOKKER-PLANCK equation for axisymmetric geometry (CORDEY 1976, ROME 1977). Assuming that the slowing down time is larger than the bounce time, it is possible to show (ROME 1977) that particle orbits between two collisions are completely determined by one of the two intersection points (rsub(M), rsub(I)) with the equatorial plane, and by the velocity v at this point. (Atomindex citation 11:532980)