THE SPES FACILITY AS AN INTENSE NEUTRON SOURCE: RADIATION RESISTANCE OF POLYMERIC MATERIALS AND RESIDUAL ACTIVATION CALCULATIONS

SPES is a new generation ISOL facility for the production of intense Radioactive Ion Beams by fission reactions at high rate. Two main topics related to the management of SPES as an intense neutron source are here discussed: the radiation resistance of polymeric components used for its construction and the residual activation of the system after machine shutdown. Radiation effects on elastomeric O-rings and lubricating grease are experimentally investigated to assure reliable operation of the facility and safe post-operation management. Experimental protocols have been developed to irradiate samples in a neutron and gamma facility of a TRIGA Mark II nuclear research reactor. Based on the results of post-irradiation mechanical tests, the most radiationresistant products are selected. A case study is dedicated to the life prediction of the O-ring of a SPES gate valve. Moreover, extensive Monte Carlo calculations are performed to evaluate the residual radioactivity of the facility after operation. The outcomes represent useful inputs to plan inspection and maintenance during the facility shutdown.