Benefits of radiocarbon dating
-counting method) or by directly counting the radiocarbon atoms using a method called Accelerator Mass Spectrometry (AMS).Measurement of the radioactivity of the sample works very well if the sample is large, but in 9 months less than 0.01% of the radiocarbon ions will decay, so in a reasonable measurement time (typically a few weeks) only a very small proportion of the radiocarbon atoms are detected by this method.
The accelerator is used to help remove ions that might be confused with radiocarbon before the final detection.
AMS, on the other hand, can in principle detect a much higher proportion (typically about 1% of the total) allowing sample sizes to be smaller by a factor of about a thousand.
The method is relatively new because it needs very complicated instruments first developed for Nuclear Physics research in the late 20th century.
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View the full list Radiocarbon dating has transformed our understanding of the past 50,000 years.