Toroidal flow velocity profile of an impurity ion in a field-reversed configuration plasma

Particle orbits of impurity ions are calculated to estimate their toroidal flow velocity. If the impurity ion flow differs from the ion flow, the Doppler shift measurement of impurity spectra requires a suitable modification of experimental results. At the field-null, the carbon ion flow coincides with the deuterium ion flow due to the friction force between them. At the separatrix, however, impurity and plasma ions have their own flow velocities. It is found that the diamagnetic drift that is dependent on the charge and mass of each fluid species dominates the toroidal flow velocity. (author)