An accelerator mass spectrometer, although a powerful tool, is also a costly one.
Establishing and maintaining an accelerator mass spectrometer costs millions of dollars.
There are two accelerator systems commonly used for radiocarbon dating through accelerator mass spectrometry.
One is the cyclotron, and the other is a tandem electrostatic accelerator.
Burning the samples to convert them into graphite, however, also introduces other elements into the sample like nitrogen 14.
When the samples have finally been converted into few milligrams of graphite, they are pressed on to a metal disc.
Radiometric dating methods detect beta particles from the decay of carbon 14 atoms while accelerator mass spectrometers count the number of carbon 14 atoms present in the sample.
Both carbon dating methods have advantages and disadvantages.
The two techniques are used primarily in determining carbon 14 content of archaeological artifacts and geological samples.
Mass spectrometers detect atoms of specific elements according to their atomic weights.
They, however, do not have the sensitivity to distinguish atomic isobars (atoms of different elements that have the same atomic weight, such as in the case of carbon 14 and nitrogen 14—the most common isotope of nitrogen).
Detectors at different angles of deflection then count the particles.
At the end of an AMS run, data gathered is not only the number of carbon 14 atoms in the sample but also the quantity of carbon 12 and carbon 13.