Fission is a phenomenon in which an atomic nucleus is deformed and split into two.By observing this "breaking method" (the balance of the weights of the two torn nuclei), it is possible to investigate how the nuclei are deformed and fission occurs. I didn't know.
This time, in a joint research between the Japan Atomic Energy Agency and Tokyo Institute of Technology, the relationship between neutron emission from nuclei and the "breaking method" of nuclei in nuclear fission was clarified for the first time.
A nucleus with high energy may undergo fission and break, but it may also undergo fission and emit neutrons to become another nucleus.If the energy is still high enough even after emitting neutrons, it may undergo fission again, and it may emit neutrons again to become another nucleus.Therefore, even if you observe the "tear" of nuclei, the data of the original nuclei and the nuclei after neutron emission are mixed, and it is not possible to obtain the observation data of "tear" only for specific nuclei, which is high energy. It was a hindrance to nuclear fission research.
In this research, we created many kinds of nuclei with various energies and observed their "tear".Then, by combining the effect of nuclear fission after neutron emission with the theoretical calculation performed by Kinki University, we first grasped the "breaking method" of individual nuclei after neutron emission.As a result, we succeeded in clarifying the breakdown of the observed "how to tear".
This result of correctly interpreting the "breaking method" of high-energy nuclei, for which even the interpretation of data has not been established for many years, leads to a deep understanding of the nuclear fission phenomenon.It is expected to contribute to transmutation technology for reducing the toxicity of radioactive materials using nuclear fission.
Paper information:[Physical Review Letters] Role of Multichance Fission in the Description of Fission-Fragment Mass Distributions at High Energies