The surrogate reactions for the neutron-capture rate using OEDO and SHARAQ in RIBF

To determine the neutron capture rates of radioactive nuclei, we have developed an experimental technique using surrogate reactions, specifically the (d, p) reaction in inverse kinematics. The gamma-emission probabilities from unbound states were deduced by identifying the outgoing reaction residues, instead of detecting the de-excitation γ rays from the compound states. Such experiments have become feasible through the use of the OEDO device, which enables beam deceleration and focusing, and the SHARAQ spectrometer at RIBF. We applied this technique to measure the neutron capture rates of 79Se for nuclear transmutation data, and of 130Sn for studies related to the r-process. In this contribution, we discuss the neutron-capture cross sections of 79Se using the surrogate ratio method, and introduce the updated experimental setup for the 130Sn measurement.