Preliminary design study of a proton irradiation laboratory for fusion materials at ESS-Bilbao

Proton for materials (P4M) is an irradiation facility proposed for the ESS-Bilbao (ESS-B) accelerator, currently under construction in Bilbao, Spain. P4M will enable users to investigate the behavior of materials for fusion reactors when irradiated with pulsed proton beams. The requirement for such a facility was highlighted by the TechnoFusiَn Project as the need to improve the knowledge about the mechanical and physical properties of materials when impacted by high energy neutrons in future fusion devices. Material irradiation by protons is capable of simulating the effects of fusion generated neutrons (14 MeV, target damaging and He and H production) with a reasonably fast dose rate, as predicted by theoretical calculations and previous experiments. Therefore, given that the ESS-B accelerator will provide an intense source of 50 MeV protons, with average currents of a few mAs, a laboratory for fusion material testing is proposed. This paper appraises the scientific feasibility of performing fusion relevant experiments as well as the tests that can be conducted. Special emphasis is placed on material damage parameters, the beam power deposition in the sample and the consequences of material activation for the laboratory design. As first results, the consequences of high power deposition and severely activation of the specimens make essential an adapted cooling system and remote handling operation.