Accelerator techniques for carbon dating
Developed by the University of Liverpool, the new technique uses a Quadrupole Mass Spectrometer, which will reduce the time it takes to get carbon-dating results from a number of weeks to just a couple of days.
Even better than that, it can be used on site without needing to send samples away.
The real advantages of AMS lie in the possibilities it offers for doing completely new kinds of measurements and using new kinds of sample materials.
For example: C has long been used as a tracer for chemical processes and pathways, the amount of tracer required using decay counting can be hazardous to the researchers, pose contamination problems or, in some cases, itself influence the process being studied.
AMS allows very low levels of tracer to be used, completely avoiding these problems.
AMS tends to be more expensive than decay counting because purchasing and maintaining a particle accelerator and its associated components is expensive.
They currently anticipate the first unit will be available to field archaeology staff for trials as soon as 2016!Collisions with carbon or gas atoms in the stripper remove several electrons from the carbon ions, changing their polarity from negative to positive. The positive ions are then accelerated through the second stage of the accelerator, reaching kinetic energies of the order of 10 to 30 million electron volts. This problem is solved in the tandem accelerator at the stripper –if three or more electrons are removed from the molecular ions the molecules dissociate into their component atoms. The kinetic energy that had accumulated up to now is distributed among the separate atoms, none of which has the same energy as a single C from the more intense "background" caused by the dissociated molecules on the basis of their kinetic energy.