Radiocarbon dating before 1950
After plants die or they are consumed by other organisms (for example, by humans or other animals) the C allows the age of the sample to be estimated.The technique of radiocarbon dating was developed by Willard Libby and his colleagues at the University of Chicago in 1949.Among others, all the tree ring samples used for the calibration curves (see below) were determined by these counting techniques.Such decay counting, however, is relatively insensitive and subject to large statistical uncertainties for small samples.
The sensitivity of the method has been greatly increased by the use of Accelerator Mass Spectrometry (AMS).Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! One of the most frequent uses of radiocarbon dating is to estimate the age of organic remains from archaeological sites. Such raw ages can be calibrated to give calendar dates.With this technique only detecting those atoms that decay during the time interval allotted for an analysis.
AMS allows dating samples containing only a few milligrams of carbon.
Raw radiocarbon ages (i.e., those not calibrated) are usually reported in "years Before Present" (BP).