Demonstrating the metrological compatibility of uranium isotope amount ratio measurement results obtained by GSMS, TIMS and MC-ICPMS techniques

Abstract

The metrological compatibility of n( 234U)/ n( 238U), n( 235U)/ n( 238U) and n( 236U)/ n( 238U) isotope amount ratio measurement results obtained by gas source mass spectrometry (GSMS), thermal ionisation mass spectrometry (TIMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) techniques in a set of low-enriched uranium samples is demonstrated in this study. The impact of the correlation between certified isotope reference materials on the metrological compatibility of measured isotope amount ratios is also discussed. The metrological concepts defined in the VIM 3rd edition and the measurement uncertainty evaluation according to the BIPM-GUM guide was thoroughly applied in this work.