Decay chains and photofission investigation based on nuclear spectroscopy of highly enriched uranium sample.

Nuclear spectroscopy experiments were performed for 100g metallic uranium rod enriched to 93% (235)U, in order to establish and characterize the most prominent γ-rays in the natural decay series and photofission reaction. Single γ-ray spectra and γ-γ coincidences measurements were conducted before irradiation. The uranium sample was subsequently irradiated with 15 MeV bremsstrahlung photons. Relative intensities of γ-lines and several values of half-lives of the fission fragments decays were determined. The obtained information can be utilized in detection of smuggled nuclear materials and characterization of bulky nuclear waste packages.