High-efficiency toroidal current drive using low-phase-velocity kinetic Alfvén waves
A method of obtaining efficient current drive in tokamaks using low-phase-velocity kinetic Alfvén waves is proposed. The wave momentum, imparted primarily to the trapped electrons by Landau damping, is stored as the canonical angular momentum via the Ware pinch. In steady state, collisions restore the pinched electrons to their original phase-space configuration and, in the process, release the stored canonical angular momentum to the background ions and electrons in proportion to their respective collision frequencies. Despite the loss of a part of the original impulse to the plasma ions, well over half the wave momentum is ultimately delivered to the bulk-plasma electrons, resulting in an efficient current drive. Optimum antenna loading conditions are described and the problem of accessibility is discussed.
Bibliographic Reference: Report: IPP4/248 EN (1991) 10 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199111649 / Last updated on: 1994-12-02
Original language: en
Available languages: en