Experimental investigation of the afterglow of the pulsed ECR discharge

During the afterglow of the pulsed ECR discharge, currents can be extracted, which are substantially higher than the ion current during the heating phase of the plasma. This is especially the case for the high charge states of heavy ions. An investigation of the shape and duration of the afterglow for the different charge states of lead compared to the afterglow pulse of the carrier gas is presented. An operating regime was found, which gave an extremely stable and reproducible afterglow. The variation from pulse to pulse is hardly visible and the long term stability is also very good. This mode, which made the setting-up and operation of the accelerators much easier than is normally the case, can also give an insight into the processes responsible for the afterglow, which are not yet fully understood.