Nitrogen normally occurs in a seven proton, seven nuetron, nitrogen-14 state.When it collides with an energetic neutron it becomes carbon-14, with six protons and eight neutrons and gives off a hydrogen atom with one proton and zero neutrons. Carbon-14 is an isotope of carbon, which exists only is small amounts in the environment (1 in one trillion carbon atoms is carbon-14).Members of the Paleochronology group presented their findings at the 2012 Western Pacific Geophysics Meeting in Singapore, August 13-17, a conference of the American Geophysical Union (AGU) and the Asia Oceania Geosciences Society (AOGS).
The stable form of carbon is carbon 12 and the radioactive isotope carbon 14 decays over time into nitrogen 14 and other particles.
Now, new applications for the technique are emerging in forensics, thanks to research funded by NIJ and other organizations.
In recent years, forensic scientists have started to apply carbon-14 dating to cases in which law enforcement agencies hope to find out the age of a skeleton or other unidentified human remains.
Over the past six decades, the amount of radiocarbon in people or their remains depends heavily on when they were born or, more precisely, when their tissues were formed.
Forensic anthropologists at The University of Arizona took advantage of this fact in a recent study funded by NIJ.