Intercomparison measurements between accelerator and laser based mass spectrometry for ultra-trace determination of 41Ca in the 10−11-10−10 isotopic range

Selective ultra-trace determination of the long-lived radioisotope 41Ca has applications in environmental and biomedical research, as well as in cosmochemistry. We have conducted an intercomparison between the two currently available methods for measurement at these low (radio) activities: accelerator mass spectrometry (AMS) and resonance ionization mass spectrometry (RIMS). Three artificially produced 41Ca samples, primarily of cosmochemical importance, with isotopic abundances in the range of 10−11-10−10 were used and results of these measurements show good agreement between the two methods, within the experimental uncertainties.