A radiocarbon measurement is termed a conventional radiocarbon age (CRA).
Over the years, other secondary radiocarbon standards have been made.
Radiocarbon activity of materials in the background is also determined to remove its contribution from results obtained during a sample analysis.
Over the years, carbon 14 dating has also found applications in geology, hydrology, geophysics, atmospheric science, oceanography, paleoclimatology and even biomedicine.
Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. Carbon 14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen 14 atoms.
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Discovery of Radiocarbon Dating (accessed October 31, 2017). Sheridan Bowman, Radiocarbon Dating: Interpreting the Past (1990), University of California Press About AMS Dating Accelerator Mass Spectrometry (AMS) dating involves accelerating ions to extraordinarily high kinetic energies followed by mass analysis.By knowing how much carbon 14 is left in a sample, the age of the organism when it died can be known.It must be noted though that radiocarbon dating results indicate when the organism was alive but not when a material from that organism was used.Liquid scintillation counting is another radiocarbon dating technique that was popular in the 1960s.In this method, the sample is in liquid form and a scintillator is added.The method does not count beta particles but the number of carbon atoms present in the sample and the proportion of the isotopes. Samples that have been radiocarbon dated since the inception of the method include charcoal, wood, twigs, seeds, bones, shells, leather, peat, lake mud, soil, hair, pottery, pollen, wall paintings, corals, blood residues, fabrics, paper or parchment, resins, and water, among others.