Time Resolved Experiments at the Frankfurt 14 GHz ECR Ion Source

S. Runkel 1, 2, K. E. Stiebing1, O. Hohn1, 2, V. Mironov3, G. Shirkov3, A. Schempp2 and H. Schmidt-Boecking1
1Institut fuer Kernphysik, J. W. Goethe-Universitaet, August-Euler-Str. 6, 60486 Frankfurt am Main, Germany
2Institut fuer Angewandte Physik, J. W. Goethe-Universitaet, Robert-Mayer-Str. 4-6, 60056 Frankfurt am Main, Germany
3Joint Institute of Nuclear Research, Dubna, Moscow Reg., 141980, Russia.

To investigate the basic production processes of highly charged ions and combined phenomena of an ECRIS plasma (e. g. influence of secondary electrons and plasma instabilities) time resolved experiments have been carried out at the Frankfurt 14 GHz ECRIS [1] (see also the contributions to this workshop by O. Hohn et al. and V. Mironov et al.).

We report time resolved measurements of the extracted ion currents by pulsing the biased disk voltage [2]. The measurements have shown that the extracted ion currents respond too fast to explain the "biased disk effect" (i. e. the intensity increase of highly charged ions) by enhanced ion breeding. Furthermore the influence of the pulsed biased disk on plasma instabilities has been investigated. It has also been shown that this method can be used to extract pulsed ion beams from an ECRIS.

[1] H. Schmidt-Boecking et al., in "Materials Research with Ion Beams", edited by H. Schmidt-Boecking, K. E. Stiebing and A. Schempp, Springer-Verlag (1992).
[2] K. E. Stiebing et al., submitted to Physical Review Special Topics: Accelerators and Beams.

Presenting Author : Runkel S.
Presentation : Poster
Wednesday Poster Session at 14:45