A joint project was undertaken by the National Bureau of Standards (NBS) Atmospheric Chemistry Group and University of Arizona (UoA) Tandem Accelerator Mass Spectrometry Group to develop and evaluate accelerator 14C measurements of 50-1000 μg carbon samples at a modest accuracy of 5-10%. FeC alloy targets prepared from standards and samples averaged 1.6 μA 12C- current. 14C measurements yielded 5% precision and accuracy, limited by a blank equivalent to 11% modern carbon for targets containing ∼ 100 μg carbon. The contamination level was estimated to be ∼ 15 μg contemporary carbon (current atmospheric 14C). These results demonstrated that the FeC target is quite suitable for atmospheric and environmental studies that require measuring fossil/biogenic carbon in microgram samples.
ASJC Scopus subject areas
- Nuclear and High Energy Physics