Speaker
Description
Treatment on high-level radioactive waste from nuclear power plants is one of the major issues in worldwide for the use of a nuclear power plant. As a promising solution, research and development has been devoted to the partitioning and transmutation technology where long-lived nuclides are converted to stable or short-lived ones for reduction and recycling. In particular, the transmutation on the long-lived fission products (LLFPs) has received much attention because the LLFP nuclei have large radiotoxicities and they can be produced continuously in the accelerator driven systems and next-generation nuclear reactors. However, experimental reaction data for LLFP nuclei are very limited.
Nuclear physics plays an essential role in addressing the treatment on LLFP, because the reliable reaction data and models are necessary towards a possible solution for LLFP transmutation. Aiming at bringing an invention to the nuclear transmutation on LLFP, we have studied the fragmentation reaction of long-lived fission product $^{137}\rm{Cs}$ at 200 MeV/u at the RIKEN RI beam factory. In addition to transmutation, fragmentation reaction plays an important role in the production of radioactive beams. Experimental data of cross sections on the fragmentation of $^{137}\rm{Cs}$ reaction will lead to a better understanding on the reaction mechanism.
To study the fragmentation of $^{137}\rm{Cs}$ the inverse kinematics technique was adopted. Namely, the $^{137}\rm{Cs}$ beam was produced by a fission of U beam and selected using the in-flight separator BigRIPS. A carbon target was used to induce the fragmentation reaction, and the reaction products were identified and analyzed using the Zero Degree spectrometer. The reaction energy was around 200 MeV/u. The isotopic distribution of the reaction cross sections has been obtained and the results are compared with various theoretical calculations with dynamical and evaporation processes as well as semi-parameterization EPAX 3.1.a.
In the presentation, the newly obtained carbon-induced fragmentation cross sections of $^{137}\rm{Cs}$ will be discussed and a comparison with theoretical calculations will be presented.
