Measurement of Mass-Independent Perturbations of Cadmium in Nuclear Debris Samples

The isotopic composition of cadmium in nuclear debris was measured by multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS). Mass-independent perturbations due to fission product decay on the isotopes of Cd were observed. Relative fission yields for masses 111, 112, 114 and 116 were determined in each sample of nuclear debris and compared with reported values found in irradiated plutonium and uranium fuels. Mass spectrometry measurements of the valley fission product endpoints are extremely challenging due to the low cumulative fission yields and small amounts of each isotope that are produced. To overcome these challenges, a new purification method for Cd was developed and validated by examination of a number of geological reference materials.