Transport of impurity ions along the field lines in magnetized plasma

A simple one-dimensional model describing the spread of laser blow-off injected ions along the magnetic field lines is presented. The model is based on the kinetic theory. A closed set of kinetic equations that contain a Coulomb collision term is solved numerically. For impurity density less than the plasma density, the effect of the ambipolar electric field is negligible, as shown. The results of the model calculation are compared with experimental results obtained on the Tokamak Experiment for Technically Oriented Research (TEXTOR) [H. Soltwisch et al., Plasma Phys. Controlled Fusion 26, 23 (1984)] tokamak by the use of injection of lithium atoms, and the agreement is satisfactory. The results of the model and possible applications for diagnostic purposes are discussed in detail. (C) 1996 American Institute of Physics.