C-14 is produced in the upper atmosphere when nitrogen-14 (N-14) is altered through the effects of cosmic radiation bombardment (a proton is displaced by a neutron effectively changing the nitrogen atom into a carbon isotope).
The new isotope is called "radiocarbon" because it is radioactive, though it is not dangerous.
It is often used in archeology and some types of biology. Plants (and other autotrophs) take in carbon dioxide gas from the atmosphere during photosynthesis.
Animals (and other heterotrophs) get their carbon by eating plants or other animals, from decaying organic matter, or from other similar sources.
Accelerator Mass Spectrometry (AMS) is a technique for measuring the concentrations of rare isotopes that cannot be detected with conventional mass spectrometers.
The original, and best known, application of AMS is radiocarbon dating, where you are trying to detect the rare isotope A nuclear particle accelerator consists essentially of two linear accelerators joined end-to-end, with the join section (called the terminal) charged to a very high positive potential (3 million volts or higher). Injecting negatively charged carbon ions from the material being analysed into a nuclear particle accelerator based on the electrostatic tandem accelerator principle. The negative ions are accelerated towards the positive potential.
This may be a solid-state detector or a device based on the gridded ionisation chamber.
The latter type of detector can measure both the total energy of the incoming ion, and also the rate at which it slows down as it passes through the gas-filled detector.
AMS allows very low levels of tracer to be used, completely avoiding these problems.Some of the carbon is a radioactive isotope called carbon-14 (C gradually undergoes radioactive decay, transforming it into nitrogen, and therefore gradually "disappears".Scientists can study samples from the once-live creatures' remains to see how much radioactive Autotrophs are organisms that can "make their own food" from an inorganic source of carbon (carbon dioxide) given a source of energy.It is naturally unstable and so it will spontaneously decay back into N-14 after a period of time.It takes about 5,730 years for half of a sample of radiocarbon to decay back into nitrogen.