Threshold behaviour and wave dispersion in an ECR-discharge

Wolters U., Wiesemann K.
Experimentalphysik insb. Gaselektronik, Ruhr-Universitaet Bochum, D-44780 Bochum, Germany

In the so called "resonance" state of an ECR-discharge the plasma is stabilized by a ring of hot electrons creating a minimum-B-configuration. Nevertheless, in pure gases an instability occurs. This instability shows the same threshold behaviour as the so called "isotope anomaly" observed in ECR ion sources and the appearance of the hot electron ring. A possible explanation for this effect is the onset of non-linear interactions of electromagnetic waves with the plasma. For a better understanding it is essential to get a picture of the wave propagation in the ECR plasma, especially the locations of the resonances and cutoff zones of the possibly occuring waves for different discharge regimes are of interest. Here we present the first results of our investigations on this topic.

Presenting Author : Wolters U.
Presentation : Poster
Monday Poster Session at 14:00