accelerator mass spectrometry

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Mass spectrometry in which a particle accelerator is used to disassociate molecules, ionize atoms, and accelerate the ions.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun physics A form of mass spectrometry in which ions are accelerated to extraordinarily high kinetic energies before mass analysis.