Measurement of fast neutron induced fission cross section of minor-actinide

not registered

In fuel cycles with recycled actinide, core characteristics are largely influenced by minor actinide (MA: Np, Am), Accurate nuclear data of MA such as fission cross section are required to estimate the effect of MA with high accuracy. In this study, fast neutron induced fission cross section of MA was measured using Dynamitron Accelerator in Tohoku University. New or improved techniques and tools with high precision and fast timing capability were developed for this study. Those are as follows: (1)Development of a sealed fission chamber,(2)Intensification of Li neutron target, (3)Improvement of time-resolution of Time-of-Right (TOF) electronic circuit, (4)Introduction of MA (Np237, Am241 and Am243) samples with large sample mass and (5)Introduction of a U235 sample with high purity. Using these improved tools and samples, fission cross section of Np237 was measured between 10 to 100 keV. On the other hand, averaged fission cross section for Maxwell distribution spectrum with kt=25.3 keV was measured for Am241 and Am243.