Ion Behavior and Gas Mixing in electron cyclotron resonance plasmas as sources of highly charged ions (concept

Abstract: An ECR ion source is basically an ECR heated plasma confinement machine, with hot electrons and cold ions. The main parameters of the ion population have been analyzed, including temperature, losses, and confinement time. The "gas mixing" effect has been studied in this context. An expression is derived for determining the ion temperature from the values of all extracted ion currents. One aim is to study the ion temperature behavior in argon plasmas without and with mixing different gases into the plasma. For that purpose a series of experiments has been performed where systematically one or a few parameters where changed. One conclusion is that the ion temperature indeed is decreasing due to gas mixing. A second conclusion is that the decreasing ion temperature is not a sufficient requirement for the beneficial effect of gas mixing to the production of highest charge states of argon.