Radiocarbon dating activities
The atoms of carbon 14 then proceed to decay exponentially, with a half life of 5,700 years.
When much later, an archaeologist examines the remains (fireplace ashes, bones, plant remains), he can date the fossil by comparing the fraction of remaining radiocarbon nuclei to the fraction existing at the time the organism stopped absorbing carbon.
The estimation assumes that the rate of formation of atmospheric carbon 14 has not changed since the days when the fossil was alive.
This is not entirely true and it is necessary to readjust the time and make corrections. When the remains to date are very old, the nuclei of carbon-14 become so rare that the observation of their decays becomes impractical. This is done in facilities designed for this purpose, made of a mass spectrograph associated with a small accelerator.
Samples of a few milligrams of the vestige to date are introduced in the installation which allows to measure the isotopic ratios of the ordinary carbon and its radioactive isotope.
The photograph shows the CEA ARTEMIS facility in Saclay (France).
The key advantage is to require minute samples of fossil for the dating.
It is in knowing what made past cultures cease to exist that could provide the key in making sure that history does not repeat itself.
Over the years, archaeology has uncovered information about past cultures that would have been left unknown had it not been with the help of such technologies as radiocarbon dating, dendrochronology, archaeomagnetic dating, fluoride dating, luminescence dating, and obsidian hydration analysis, among others.
This radioactive isotope of carbon is present in the atmosphere in trace amounts, and in chemical processes is indistinguishable from normal carbon 12.
As a result, animal and plant life regularly assimilate carbon 14 atom together with the usual carbon 12.