Spallation reaction study for the long-lived fission product ¹⁰⁷Pd

Spallation reactions for the long-lived fission product 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained at 196 and 118 MeV/nucleon in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. It was found that the proton-induced cross sections at 196 MeV/nucleon are close to those for deuteron obtained at 118 MeV/nucleon for the light-mass products. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intranuclear cascade and evaporation processes. Our data give a design goal of proton/deuteron flux for the transmutation of ¹⁰⁷Pd using the spallation reaction. In addition, it is found that the spallation reaction at 118 MeV/nucleon may have an advantage over the ¹⁰⁷Pd transmutation because of the low production of other long-lived radioactive isotopes.