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  2. Carbon-14 - Wikipedia

    en.wikipedia.org/wiki/Carbon-14

    Carbon-14, C-14, 14 C or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.Its presence in organic matter is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues (1949) to date archaeological, geological and hydrogeological samples.

  3. Radiocarbon dating - Wikipedia

    en.wikipedia.org/wiki/Radiocarbon_dating

    C concentration almost exactly cancels out the decrease caused by the upwelling of water (containing old, and hence 14 C-depleted, carbon) from the deep ocean, so that direct measurements of 14 C radiation are similar to measurements for the rest of the biosphere. Correcting for isotopic fractionation, as is done for all radiocarbon dates to ...

  4. Isotopes of carbon - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_carbon

    Carbon (6 C) has 14 known isotopes, from 8 C to 20 C as well as 22 C, of which 12 C and 13 C are stable.The longest-lived radioisotope is 14 C, with a half-life of 5.70(3) × 10 3 years. . This is also the only carbon radioisotope found in nature, as trace quantities are formed cosmogenically by the reactio

  5. Radioactive decay - Wikipedia

    en.wikipedia.org/wiki/Radioactive_decay

    Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha, beta, and gamma decay.

  6. Radioactivity in the life sciences - Wikipedia

    en.wikipedia.org/wiki/Radioactivity_in_the_life...

    Carbon-14 labeling is common in drug development to do ADME (absorption, distribution, metabolism and excretion) studies in animal models and in human toxicology and clinical trials. Since tritium exchange may occur in some radiolabeled compounds, this does not happen with carbon-14 and may thus be preferred.

  7. Calculation of radiocarbon dates - Wikipedia

    en.wikipedia.org/wiki/Calculation_of_radiocarbon...

    The calculation of radiocarbon dates determines the age of an object containing organic material by using the properties of radiocarbon (also known as carbon-14), a radioactive isotope of carbon. Radiocarbon dating methods produce data based on the ratios of different carbon isotopes in a sample that must then be further manipulated in order to ...

  8. File:Carbon14 with activity labels.svg - Wikipedia

    en.wikipedia.org/wiki/File:Carbon14_with...

    English: Changes in the 14 C record, which are primarily (but not exclusively) caused by changes in solar activity. Note that "before present" is used in the context of radiocarbon dating , where the "present" has been fixed at 1950.

  9. Isotopes of nitrogen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_nitrogen

    Nitrogen-14 is the source of naturally-occurring, radioactive, carbon-14. Some kinds of cosmic radiation cause a nuclear reaction with nitrogen-14 in the upper atmosphere of the Earth, creating carbon-14, which decays back to nitrogen-14 with a half-life of 5700(30) years .