Accelerator Mass Spectrometry (AMS) is a method of radiocarbon dating using an accelerator ANTARES to count rare individual carbon 14 (14C) isotopes in a carbon sample. Most carbon atoms, Carbon 12, are stable but 14C atoms are radioactive and decay over time. In very simple terms, when an organism dies C14 begins to radioactively decay at a an established rate, so by counting the number of C12 atoms compared to C14 scientists can calculate the age of the sample. An accelerator is used to separate the different isotopes by their unique mass, and allows us to determine the isotopic composition of one or more elements in a compound.

Accelerator mass spectrometry (AMS) differs from other forms of mass spectrometry in that it accelerates ions to extraordinarily high kinetic energies before mass analysis. AMS is exceptional in its ability to sensitively and accurately analyze elemental and isotopic compositions.