Assessment of radiation dose rate resulting from activated corrosion products in the PRIMA facility cooling loops

PRIMA (Padova Research Injector Megavolt Accelerated) is the name of the ITER neutral beam facility currently under construction at the RFX Consortium located in Padua – Italy. PRIMA consists of two injectors which will test at the same time the ion source (SPIDER) and the whole system (MITICA). Both injectors accelerate negative deuterium and hydrogen ions with a maximum energy of 1 MeV for MITICA and 100 keV for SPIDER, with a maximum beam current of 40 A. Accelerated ions are stopped on a CuCrZr alloy calorimeter. ion in deuterium leads to production of an intense neutron flux through D–D and D–T reactions on the calorimeter panels which is likely to activate materials and components around the injectors, among which the corrosion products formed in the cooling loops; the radioactivity of the activated corrosion products (ACPs) may persist even after injector shutdown, representing a relevant radiation protection issue during repair and inspection activities. present paper the occupational radiation exposure (ORE) is evaluated. The total amount of radioactivity produced inside the cooling loops is calculated under different operative conditions and the radiation dose received by workers carrying out maintenance activities on the injector is also assessed for both experiments.