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The authors have extended their previous collisional-regime theory for rotation and impurity transport in a tokamak plasma with strong, directed NBI and strong rotation (v? vth) to the plateau regime. The paper gives a summary of a kinetic theory derivation of the parallel viscous force in the strong rotation ordering and a self-consistent formalism for calculating ion and impurity rotation velocities and radial transport fluxes, as well as the radial electric field and the poloidal variation of the impurity density upon which the former strongly depend. Calculations for model problems representative of ISX-B and PLT are presented. The predicted impurity transport exhibits features that are in agreement with experimental observations.

In divertors and pumped limiters, plasma flows along magnetic field lines from the scrape-off layer to a material wall where it is neutralized. The neutrals refluxing from the wall will undergo ionization and charge exchange, producing cold ions. This problem has been examined by using a largely analytical, collisionless kinetic model which includes the effects of charge exchange. Cases with uniform magnetic field and with magnetic fields possessing a constriction (as in a bundle divertor) are treated. The cold ions increase the electric potential over that which otherwise would exist. Solutions are found with a peak in the potential near the plate, with cold ions flowing down the potential gradient either toward the scrape-off zone or towards the wall, depending on where they are produced. This is in agreement with the predictions of fluid theories and numerical kinetic calculations. The net effect is to reduce the heat flux in hot ions to the divertor plate, desirable for reducing sputtering loss. This analytical approach can be used to produce computationally efficient routines to determine particle and energy losses from the scrape-off layer which are suitable for inclusion in transport codes.

Presents the poem "February," by A.W. Bailey.

Presents the poem "Irrigating: Waiting for Water, Denair, California," by A.W. Bailey.