Reduction in the quantity of high-level radioactive waste in the spent fuel is one of the major issues for the use of a nuclear power plant. Research and development into the reduction of radioactive waste using partitioning and transmutation technology has been performed over recent decades. In particular, the transmutation on the long-lived fission products (LLFPs) has received much attention.
Aiming at bringing a new invention to the nuclear transmutation on LLFP, we have studied the proton- and deuteron-induced spallation reactions for the long-lived fission products 137Cs (half-life = 30 years) and 90Sr (half-life = 29 years). Our study is the first attempt in the history of nuclear physics to solve the problem of the LLFP transmutation and has triggered the reaction studies for other long-lived fission products.
The cross sections were measured in inverse kinematics using secondary beams of 137Cs and 90Sr at the RIKEN Radioactive Isotope Beam Factory. The target dependence of cross section has been investigated systematically and the experimental data were compared with the spallation model including cascade and evaporation processes. In the seminar, the results on the spallation of 137Cs and 90Sr as well as the potential of spallation reaction on the LLFP transmutation will be discussed.