The number of emissions in a given time period is proportional to the amount of residual carbon-14. The introduction of an instrument called an accelerator mass spectrometer has brought about a major advance in radiocarbon dating.

What instrument is used in radiometric dating?

Thermal ionization mass spectrometer Thermal ionization mass spectrometer used in radiometric dating. To determine the ages in years of Earth materials and the timing of geologic events such as exhumation and subduction, geologists utilize the process of radiometric decay.