Elastic and inelastic scattering reactions on structural materials have a significant impact on the simulation of neutron transport. The nuclear data of structural materials of interest for nuclear reactors and criticality studies must be known with good precision over a wide incident neutron energy range, from a few tens of meV to several MeV. The thesis proposal aims to carry out a systematic study of the scattering reactions above the resolved resonance range up to 5 MeV. In this energy range, neither the R-Matrix formalism nor the statistical Hauser-Feshbach model are valid for structural materials. A new formalism will be developed by using high-resolution measurements of the scattering angular distributions. This work will focus more precisely on measurements already done at the JRC-Geel facility (sodium [1], iron [2]) and will be extended to other elements studied within the framework of the IAEA/INDEN project, such as copper, chromium and nickel. As part of this thesis, the experimental database will be complemented by new measurements on the copper isotopes (Cu63 and Cu65). The measurements will be carried out at JRC Geel GELINA facility with the ELISA detector. Concerning the copper isotopes, integral benchmarks from the ICSBEP database revealed several issues in the nuclear data libraries, which provide contradictory integral feedbacks on the nuclear data of U235. For example, the ZEUS benchmarks, which is routinely used to study the capture cross section of U235 in the fast neutron energy range, are very sensitive to the nuclear data of copper. This type of benchmark will provide an ideal framework for quantifying the impact of any new formalism developed to evaluate the nuclear data of structural materials.

This study will allow the PhD student to develop skills in experimental and theoretical nuclear physics, as well as in neutron physics. The results will be communicated to the JEFF working group of the Nuclear Energy Agency (OCDE/AEN).

[1] P. Archier, Contribution à l’amélioration des données nucléaires neutroniques du sodium pour le calcul des réacteurs de génération IV, Thèse, Université de Grenoble, 2011.
[2] G. Gkatis, Study of neutron induced reaction cross sections on Fe isotopes at the GELINA facility relevant to reactor applications, Thèse, Université Aix-Marseille, 2024.