Two-Step Target for Fission Product Radioactive Beam Production

65480 The production of intense fission product radioactive beams used for nuclear physics research requires special target approaches. One such approach is that of a two-step target, in which an energetic, intense light-ion beam strikes a cooled heavy metal target to create neutrons, and the neutrons cause fissions in a surrounding blanket to make the fission products. However, such a target has not been demonstrated to work using an intense production of light ions. This project will construct a prototype two-step target and demonstrate the efficacy of the concept. Phase I produced a numerical analysis of a two-step target, defining the dimensions and constituents of a prototype target. The analysis included estimates of neutron production, fission rates, and energy deposition in the primary and secondary targets. This was followed by a thermal analysis using finite element approaches to devise cooling strategies for the primary target and thermal control approaches for the secondary target. Phase II will demonstrate the efficacy of a prototype two-step target using an intense production beam. The analyses of the thermal performances of the target components from the Phase I study will be extended, and a prototype test target will be designed in detail, fabricated, and integrated into a test configuration at the TRIUMF accelerator. Commercial Applications and Other Benefits as described by the awardee: This technology should lead to the commercial provision of targets for intense radioactive beam facilities, including the new nuclear physics initiative, the Rare Isotope Accelerator.