On methods of measuring the relative plasma composition by active charge exchange
Two methods of measuring the hydrogenic composition of a plasma with an active diagnostic beam are discussed: evaluation at equal energies of the neutrals leaving the plasma and at equal velocities. Evaluation at equal velocity has the advantage that the plasma composition, particle penetration and stripping efficiency of the analyser do not enter the evaluation. The only plasma parameter that has to be known is the plasma temperature. If measurement at two different velocities is possible, the temperature can also be evaluated from the corresponding four fluxes without any further knowledge of plasma or beam parameters. The circumstances under which evaluation of the plasma composition for non-Maxwellian distribution functions is possible are discussed. As the halo effect may be the main source of error, it is shown that the application of a helium beam may reduce this problem considerably.
Bibliographic Reference: Report: IPP 1/259 EN (1991) 11 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199111176 / Last updated on: 1994-12-02
Original language: en
Available languages: en