Improvement in the particle collection method to mitigate the mixing effect during uranium isotope analysis of environmental samples using secondary ion mass spectrometry

Abstract

We introduce an improved particle collection method for uranium isotopic analysis using secondary ion mass spectrometry (SIMS). A new design was applied to a vacuum-suction impactor to promote the dispersibility of collected particles and the air flow rate was adjusted to maximize the particle recovery yield. The improved method remarkably mitigated the 'mixing effect'. Materials from a nuclear forensic exercise were also employed to evaluate the method applicability. This innovation will be useful to improve the accuracy of SIMS uranium particle analysis, especially for overloaded samples with mixed isotope compositions.