Speaker
Description
Neutron fission cross-sections of minor actinides (MAs) are important to design reactors with MA-loaded fuels. Among the fission cross-sections of MAs, particularly $^{245}$Cm shows a noticeable difference between existing measured data and JENDL-5 [1] below 10 eV. A research project entitled “Improvement of accuracy of neutron-induced fission reaction data for MAs” is currently ongoing, which targets the fission cross-sections of MAs (i.e., $^{237}$Np, $^{241}$Am and $^{245}$Cm). The fission measurement of $^{245}$Cm was performed at the Accurate Neutron-Nucleus Research Measurement Instrument (ANNRI) of the Materials and Life Science Experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC). A sample employed to measure capture cross-section of $^{244}$Cm [2] was adopted, including 2.4% of $^{245}$Cm which was compared to 43.9% of $^{244}$Cm at time of fission measurement. Preliminary fission cross-section results were obtained by counting prompt fission neutrons with EJ-276D pulse-shape discriminating plastic scintillators. Owing to a small amount of $^{245}$Cm in the sample it was necessary to carefully extract the $^{245}$Cm events from the large $^{244}$Cm events. Some fission resonance peaks of $^{245}$Cm were found below 10 eV. The resonance shape analysis was made with the R-matrix analysis code AMUR [3].
In the presentation the results obtained will be given with the experimental methodology of fission cross sections at ANNRI in MLF of J-PARC.
Acknowledgment
This work was supported by MEXT Innovative Nuclear Research and Development Program Grant Number JPMXD0224020564.
[1] O. Iwamoto, N. Iwamoto, S. Kunieda et al., J. Nucl. Sci. Technol., 60(1), 1-60 (2023)
[2] A. Kimura, T. Fujii, S. Fukutani et al., J. Nucl. Sci. Technol., 49(7-8), 708-724 (2012)
[3] S. Kunieda, S. Endo, A. Kimura, EPJ Web of Conferences, 281, 00017 (2023)
| Contribution category | Theory |
|---|---|
| Presenter status | Faculty/Staff |