Particle orbit simulations on ion loss at the edge of a tokamak with separatrix configuration

Particle orbit simulations are carried out to study the ion orbits and loss at the edge of a tokamak plasma with double null magnetic separatrix. The ion loss conditions are examined as a function of υparallel/υ0 and the distance of ion launching points from the magnetic separatrix in cases both without and with radial electric field. The simulation results are compared with the theoretical ones. Good agreements and detailed features are obtained in the simulations. As a reference study, the effect of a radial electric field profile similar to that obtained in DIII-D is examined. (author)