Progress on the chemical separation of fission fragments from 236Np produced by proton irradiation of natural uranium target

The aim of the current work is to develop and validate a radiochemical separation scheme capable of separating both 236gNp and 236Pu from a uranium target of natural isotopic composition (~1g uranium) and ~200 MBq of fission decay products. A target containing 1.2g of UO2 was irradiated with a beam of 25MeV protons with a typical beam current of 30 μA for 19h in December 2013 at the University of Birmingham Cyclotron facility. Using literature values for the production cross-section for fusion of protons with uranium targets, we estimate that an upper limit of approximately 250Bq of activity from the 236Np ground state was produced in this experiment. Using a radiochemical separation scheme, Np and Pu fractions were separated from the produced fission decay products, with analyses of the target-based final reaction products made using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and high-resolution α particle and γ-ray spectrometry. •Development of a radiochemical separation scheme for separating 236gNp.•Measurements using α and high-resolution γ-ray spectrometry.•γ-ray spectroscopy used indicates presence of 236Np ground state.•Clear signature of 236Pu characteristic lines.