The limitation of Libby’s original technique was the relatively large quantity of sample required (grams of carbon). This limitation was overcome by the development of
AMS. One of the earliest AMS instruments was constructed at the University of Arizona in 1981, as a joint project between the Departments of Physics and Geosciences and funded through the National
Science Foundation. This machine is still operational.
Since then the total number of radiocarbon samples processed in the laboratory is approaching 60,000.
The number of analyses has steadily increased. The addition of a second AMS instrument in 2000 brought our instrumentation up to date and
expanded our analytical capabilities.