New method to improve He-removal performance of pump limiter by RF ponderomotive force
A new method to improve He-removal performance of a pump limiter by using RF ponderomotive force is proposed. Part of the helium neutralised at the plate in the pump limiter is re-ionised by the plasma in the channel under the limiter blade (scoop) and flows back out of the scoop. The method proposed is to suppress this back stream and improve the He exhaust rate by an application of RF ponderomotive force. When the frequency is slightly above the cyclotron frequency of low energy re-ionised He(+)ions, the ponderomotive force is applied only on the He(+)ions to reduce the back stream and the He pumping efficiency is improved. This method can be extended to improve tritium inventory together with He ash removal by choosing the frequency slightly above the tritium cyclotron frequency.
Bibliographic Reference: Report: PSC-37 EN (1994) 15 pp.
Availability: Available from Plasma Science Center, Nagoya University, Nagoya 464-01 (JP)
Record Number: 199411254 / Last updated on: 1994-11-25
Original language: en
Available languages: en