Radiocarbon dating using Accelerator Mass Spectrometry (AMS)
differs from the decay counting methods in that the amount of 14C in the sample is measured
directly, rather than by waiting for the individual radioactive decay events to occur. This makes the technique 1,000 to 10,000 times more sensitive than decay counting. The enhanced sensitivity is achieved by accelerating sample atoms as ions to high
energies using a particle accelerator, and using nuclear particle detection techniques. A photograph and a schematic diagram of the
new 3 MV AMS machine at the University of Arizona are shown below.