Isotope- and Element-Resolved Analysis of (Trans)uranium Content of Curium Targets for Heavy-Actinide Production after Intense Neutron Irradiation in the High Flux Isotope Reactor

Curium is the heaviest element resulting from nuclear power generation and is present in spent nuclear fuel. Macroscopic amounts of transcurium elements are produced by high thermal-neutron flux irradiation of curium targets in a complex process involving many neutron captures and β– decays. Competing neutron-induced fission decays enrich the resulting element mixture with lanthanides, necessitating a lanthanide-actinide separation before processing of the transcurium fraction. We report on the characterization of an aliquot of a solution from campaign 79 at the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL) taken before the chemical separation of the lanthanide fission products. The sample was characterized and quantified using α and γ spectrometry, as well as resonance ionization mass spectrometry (RIMS). The absolute content of 19 isotopes in the element range from Np to Cf was determined with typical uncertainties of 20% (1σ).