High precision 14C measurements with the HVEE Tandetron AMS system at Nagoya University

In 1996/1997, a 14C-AMS system (model 4130-AMS) manufactured by High Voltage Engineering Europe (HVEE), B.V., The Netherlands, was installed at the Center for Chronological Research (CCR), Nagoya University. The system provides highly precise and accurate 14C determinations as well as δ13C values for graphite targets (1.5 mg carbon and 3 mg iron powder) prepared from standards and samples. One sigma errors in 14C ages typically range from ±20 to ±40 yr for materials younger than 8000 BP, depending on absolute 14C ages or 14C counting uncertainties. Standard deviations of 13C/12C ratios range from ±0.1‰ to ±0.9‰. For relatively young samples, accuracies of less than 10‰ are obtained using IAEA reference materials and FIRI test samples. Background levels on the 14C-AMS system range from 52 to 54 ka BP for a pure graphite powder. The HVEE 14C-AMS system at the CCR has been used routinely to date samples with a variety of research applications.