Radiokarbonis

Radiokarbonis, commonly known as radiocarbon, refers to the radioactive isotope of carbon with a mass number of 14. It is produced in the Earth’s upper atmosphere when cosmic rays convert nitrogen-14 into 14C. The isotope rapidly oxidizes to carbon dioxide and becomes part of the global carbon cycle. Through photosynthesis, plants incorporate 14C, and animals acquire it by consuming plants or other organisms. Because living organisms exchange carbon with their surroundings, the ratio of 14C to stable carbon isotopes in a living thing remains in equilibrium with the atmosphere.

When an organism dies, it stops exchanging carbon, and the 14C present begins to decay to nitrogen-14 via beta decay. With a half-life of about 5,730 years, the remaining amount of 14C decreases predictably over time. Measuring the current 14C activity relative to a modern standard allows age estimation for formerly living materials. The two principal measurement approaches are accelerator mass spectrometry (AMS), which counts 14C atoms directly, and radiometric beta counting, which detects emitted beta particles after chemical preparation. To convert measured activity into calendar ages, results are calibrated against independent time markers such as dendrochronology (tree rings) to account for historical fluctuations in atmospheric 14C.

Limitations include variations in 14C production, reservoir effects (especially in marine contexts, where apparent ages can be older due to mixing with older carbon), and a practical dating ceiling around 50,000 to 60,000 years. Radiokarbonis dating is widely used in archaeology, geology, paleoclimatology, art authentication, and environmental science, providing a key tool for establishing chronologies of recent to late Quaternary materials.