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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.
The following nuclear reaction is the main pathway by which 14 C is created: n + 14 7 N → 14 6 C + p. where n represents a neutron and p represents a proton. [13] [14] [note 3] Once produced, the 14 C quickly combines with the oxygen (O) in the atmosphere to form first carbon monoxide (CO), [14] and ultimately carbon dioxide (CO 2). [15] 14 C ...
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
For instance, carbon-14 has a half-life of 5,730 years. After an organism has been dead for 60,000 years, so little carbon-14 is left that accurate dating cannot be established. On the other hand, the concentration of carbon-14 falls off so steeply that the age of relatively young remains can be determined precisely to within a few decades. [13]
Carbon-14 is formed in upper layers of the troposphere and the stratosphere at altitudes of 9–15 km by a reaction that is precipitated by cosmic rays. [66] Thermal neutrons are produced that collide with the nuclei of nitrogen-14, forming carbon-14 and a proton. As such, 1.5% × 10 −10 of atmospheric carbon dioxide contains carbon-14. [67]
One of the most widely used and well-known absolute dating techniques is carbon-14 (or radiocarbon) dating, which is used to date organic remains. This is a radiometric technique since it is based on radioactive decay. Cosmic radiation entering Earth's atmosphere produces carbon-14, and plants take in carbon-14 as they fix carbon dioxide ...
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After making the clay vessel fish was prepared in the vessel over a fire. The archaeologists made sure some of the fish stuck to the pot. The pot and some of the burnt crust at the bottom were tested which showed a Carbon-14 14 C age of 700 years old. Felix Riede estimated at the time the use of the Carbon-14 method maybe off by 2,000 years. [4]