14c12c ratio carbon dating
Used to calculate the fractionation correction in radiocarbon dating.
δ 14C: The 14C isotopic ratio of a material relative to the modern standard, without any correction for fractionation.
It is important to note that the CRA is calculated from a measurement of an isotopic ratio, ie radiocarbon dating does not measure time directly.
Radiocarbon ages are inferred from the measurements subject to a number of assumptions and qualifications. Cosmic Ray: The high energy atomic radiation that bombards the earth from space.
Cosmic ray particles are predominantly high energy protons and 4He nuclei ( α -particles).
Part of the cosmic ray flux originates at the sun, and is generated by solar flare events. The mechanisms giving rise to the highest energy cosmic rays are not well understood.
AMU: Abbreviation of Atomic Mass Unit, a convenient way for representing the masses of atoms.Eg the hydrogen nucleus consists of a single proton, so hydrogen has atomic number 1, the carbon nucleus has 6 protons and carbon has atomic number 6.