Radiocarbon dating by accelerator mass spectrometry
Carbon dating works because there are three naturally-occurring isotopes, or forms, of carbon, known as carbon-12, -13, and -14.
The tiny amount left, only one carbon atom in a trillion, is carbon-14.
Soon, Penn State will complete the preparation process by converting the carbon dioxide to graphite targets that will be analyzed by the new AMS.
By the time the Penn State AMS facility is running at full tilt, it will be able to process and analyze up to 10,000 samples a year, from forensic cases, archaeological digs, and studies involving soil, sediment, water, and air.
After thorough cleaning, a small amount of the material is vacuum-sealed in a quartz tube, which is then heated to a high temperature to convert the material to carbon dioxide, water, and nitrous oxides.
Kennett currently directs the Human Paleoecology and Isotope Geochemistry Laboratory in the Department of Anthropology, where materials are prepared for carbon-14 analysis.It will enable precise dating of carbon-containing material with ages stretching back over the past 50,000 years." "This new facility will improve our ability to study human-environmental interactions where chronology is key," adds Kennett.