The Ratio of the Uranium-233 to Uranium-235 Fission Cross Section

Measurements of the ²³³U: ²³⁵U fission cross-section ratio were carried out in the energy ranges 0.1 to 3.0 MeV and 4.5 to 7.5 MeV with accuracies of ≈1%. Relative masses of the fissile samples were obtained from the alpha activities and also from the relative thermal fission ratios.