The multi megawatt target station integration of the MAFF/PIAFE fission target design

The European Isotope Separation On-Line Radioactive Ion Beam Facility (EURISOL) is set to be the ‘next-generation’ European Isotope Separation On-Line (ISOL) Radioactive Ion Beam (RIB) facility. It will extend and amplify current research on nuclear physics, nuclear astrophysics and fundamental interactions beyond the year 2010.In EURISOL, four target stations are foreseen, three direct targets of approximately 100 kW of beam power and one multi-MW liquid metal proton-to-neutron converter, all driven by a high-power particle accelerator. In the aforementioned multi-MW target assembly, high-intensity RIBs of neutron-rich isotopes will be obtained by inducing fission in several actinide targets surrounding a liquid metal spallation neutron source.This article summarises the work carried out within Task 2 of the EURISOL Design Study, with special attention to the coupled neutronics of the liquid converter and fission target (MAFF/PIAFE design like) and the overall performance of the facility, which will sustain fast neutron fluxes of the order of 1014 n/cm2/s/MW of beam. The production of radionuclides in the actinide targets as well as in the liquid metal is also evaluated, showing that an in-target production of 1013 Sn132/s per actinide target can be achieved.Some of the greatest challenges in the design of high power spallation sources are the high power densities, entailing large structural stresses, and the heat removal, requiring detailed thermo-hydraulics calculations. Alternatively, a windowless target configuration has been proposed, based on a liquid mercury transverse film design. With this design, higher power densities and fission rates may be achieved, also avoiding the technical issues related to the beam window.