Measurements of neutron induced fission cross section ratios of ²³²Th, ²³³U, ²³⁴U, ²³⁶U, ²³⁸U, ²³⁷Np, ²⁴²Pu, and ²⁴³Am, relative to ²³⁵U around 14 MeV

The neutron induced fission cross sections of actinides around 14 MeV are the basic parameters for the design of a fusion-fission hybrid reactor, an accelerator breeder reactor, a transmutation system of actinides waste and dosimetry. However, previous experimental data are scarce and often show discrepancies beyond the quoted uncertainties, thus they are insufficient to meet the accuracy required by the nuclear reactor designers. Therefore, new data with high precision are required to reduce the uncertainties. This paper presents the neutron induced fission cross section ratios of ²³²Th, ²³³U, ²³⁴U, ²³⁶U, ²³⁸U, ²³⁷Np, ²⁴²Pu and ²⁴³Am relative to ²³⁵U around 14 MeV. The measurements were carried out at the Tohoku University 4.5 MV Dynamitron accelerator facility, using a back-to-back parallel plate ionization chamber. Detailed uncertainty analyses were performed by considering the correlations among the various error sources to clarify the correlations between the measured data. The paper describes the method of measurements and the data analyses in detail and discusses the results.