Sources of error in radiocarbon dating
They also sampled artifacts from museums such as a piece of timber from Egyptian pharaoh Senusret III’s funerary boat, an object whose age was known by the record of its owner’s death.
In 1949, Libby and Arnold published their findings in the journal Science, introducing the “Curve of Knowns.” This graph compared the known age of artifacts with the estimated age as determined by the radiocarbon dating method.
Based on Korff’s estimation that just two neutrons were produced per second per square centimeter of earth’s surface, each forming a carbon-14 atom, Libby calculated a ratio of just one carbon-14 atom per every 10 carbon atoms on earth.
Libby’s next task was to study the movement of carbon through the carbon cycle.
Further research by Libby and others established its half-life as 5,568 years (later revised to 5,730 ± 40 years), providing another essential factor in Libby’s concept.It showed all of Libby’s results lying within a narrow statistical range of the known ages, thus proving the success of radiocarbon dating.Top of page The “Curve of Knowns” compared the known age of historical artifacts associated with the Bible, Pompeii, and Egyptian dynasties with their age as determined by radiocarbon dating.To test the technique, Libby’s group applied the anti-coincidence counter to samples whose ages were already known.Among the first objects tested were samples of redwood and fir trees, the age of which were known by counting their annual growth rings.