Research on Discrepancy of Inelastic Cross Section for ⁵⁶Fe in Fast Neutron Range

Knowledge about the inelastic scattering cross section of ⁵⁶Fe is very important in neutron transportation calculation. However there are great discrepancies not only between experimental data but also between evaluated data. More detail analysis was performed for inelastic scattering cross section in the fast range up to 20 MeV where there are significant differences among the main evaluated libraries, mainly caused by the different inelastic scattering cross section measurements. The large discrepancies on ⁵⁶Fe(n, n₁'γ) cross section which could fill the neutron energy blank of the ⁵⁶Fe(n,inl) were clarified and were converted to the inelastic scattering cross section of ⁵⁶Fe. And the high-quality results were evaluated by using the unitarity constrain among total cross section, noelastic reaction and other reactions. The integral experiment result indicates that the new evaluated result of inelastic cross section brings greater improvement than that of CENDL-3.1.