Radioactive dust levitation and its consequences for fusion devices

Small particles (dust) exist in magnetic confinement fusion devices. Their origin is due to plasma-surface-interactions. Dust particles may contain significant amounts of hydrogen isotopes, 50% of which will be Tritium in future devices. The radioactive decay of Tritium incorporated into carbonaceous dust may lead to its charging and to the formation of a nuclear induced plasma associated with levitation and transport of dust inside the vacuum vessel. We will discuss the experimental evidence of dust levitation and removal by appropriately shaped electric fields and we will discuss some aspects of radioactive dust in fusion devices. (orig.)