Main Results of Neutronical Study about ADS with Ion Beams and Implications on Experiments Planning

The conditions which maximize the efficiency of an accelerator driven systems (ADS) are reviewed. The influence of particle beam, accelerator type, target geometry and composition are studied, searching for the conditions which ensure high energy gain, safe exploitation and deeper burning of the actinides, with longer periods between refueling. A core with criticality coefficient k eff of 0.985–0.988, lower enrichment, converter of beryllium with radius 10–20 cm and length 110–120 cm represents a proper choice. The advantage of ion beams from 7 Li and 20 Ne with energies from 0.25 to 0.75 AGeV is underlined. Values of the energy gain in the range 20–50 can be attained with ion beams. A proposal for the design of a target dedicated to the experimental study is presented. The target consists of rods from enriched U (5–10% 235 U) distributed in 6–8 layers inside a cylinder from Pb or graphite, with length 150 cm and radius 70 cm.