Performance Evaluation of the New AMS System at Accium BioSciences

Abstract

A new compact accelerator mass spectrometry (AMS) system dedicated to the measurement of radiocarbon has been commissioned at the Accium BioSciences headquarters in Seattle. The entire facility (including ancillary laboratories for the preparation of graphite targets) has been designed to handle samples with a wide range of 14C concentrations. In this paper, we discuss the technical details of the new facility and present performance test results demonstrating state-of-the-art capabilities. In particular, modern samples can be readily measured with 0.3% precision and accuracy, machine background levels are consistently in the low 1016 (14C/12C), and chemical background is approximately equivalent to a fraction of modern of 0.004. In addition, when 100-times-modern samples were processed, no increase in background was observed, either during sample processing or during AMS measurement. This corresponds to a dynamic range for 14C analysis of 6 orders of magnitude.