What is radiocarbon dating used for
After pretreatment, samples for radiocarbon dating are prepared for use in an accelerator mass spectrometer by converting them into a solid graphite form.
This is done by conversion to carbon dioxide with subsequent graphitization in the presence of a metal catalyst.
Ions from a cesium gun are then fired at the target wheel, producing negatively ionized carbon atoms.
These negatively ionized carbon atoms pass through focusing devices and an injection magnet before reaching the tandem accelerator where they are accelerated to the positive terminal by a voltage difference of two million volts.
An accelerator mass spectrometer has a run time of a few hours per sample.
Lastly, it must be noted that AMS measurements usually achieve higher precision and lower backgrounds than radiometric dating methods.
Mass spectrometers detect atoms of specific elements according to their atomic weights.
The negatively charged carbon atoms, however, move on to the stripper (a gas or a metal foil) where they lose the electrons and emerge as the triple, positively charged carbon atoms.
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.
An accelerator mass spectrometer, although a powerful tool, is also a costly one.
Establishing and maintaining an accelerator mass spectrometer costs millions of dollars.