Resolving isobaric interference in the determination of Nd isotopes using laser ionisation mass spectrometry towards atom percent fission measurements

Abstract

In the nuclear industry, burn-up is one of the crucial parameters used to monitor the fuel performance. One of the major drawbacks of conventional methods for burn-up determination is prior chemical separation of the burn-up monitor, e.g. neodymium (Nd) from samarium (Sm), to overcome isobaric interference or abundance correction using non-interfering isotopes. The present study demonstrates the potential application of the Laser Ionisation Mass Spectrometry (LIMS) technique for the quantitative estimation of Nd isotopes without prior chemical separation and abundance correction. By tuning laser parameters, the isobaric interference is discriminated in situ by LIMS. This study shows that LIMS can be a potential alternative technique to determine the atom percentage (at%) fission or burn-up of nuclear reactor fuel with an accuracy and precision better than 6% and 5%, respectively. The present study is the first of its kind to our knowledge to resolve the isobaric interference of the burn-up monitor Nd from Sm by using LIMS. This study discusses the findings of optimised laser parameters, the calibration plot, the correlation coefficient, the limit of detection (LOD), relative standard deviation (RSD), and accuracy for quantifying Nd isotopes using LIMS.