In 1979 when accelerator mass spectrometry was started in the Netherlands, Gove (1978) and Litherland (1980) demonstrated that a tandem accelerator is eminently suited for this work. Isotope ratios below 10−15 could be determined and applications were stimulated on numerous fields of research. 14C dating in particular would become an important application because smaller samples could be employed and more complex dating problems could be attacked. However, the 5% accuracy reached at that time had to be improved towards the 0.5% obtained with the conventional method of counting decays. Purser and Hanley (1978) pointed out that this high accuracy could be reached in facilities especially dedicated to dating. Rapid switching between measurements on different isotopes turned out to be crucial (Suter et al, 1981). We decided to proceed in two phases. In the first phase, the existing EN-tandem facility would be used as before and modified for the detection of 14C ions. From measurements with 14C ions from different samples, information would be obtained about the limitations of the existing facility. In the second phase, this information would be used to develop a facility in which accurate measurements of isotope ratios can be performed for elements throughout the periodic system. Conventional 14C dating will be extended in collaboration with the Isotope Physics Laboratory in Groningen. Also, applications with other elements will be studied. The improved facility is scheduled for operation in the spring of 1983.
Progress in Radiocarbon Dating with the Chalk River MP Tandem Accelerator
