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Methods of Analysis

Two basic methods of analysis are used in isotopic studies: decay counting and mass spectrometry.

Decay counting methods are used for fast-decaying radioactive isotopes. By measuring the number of alpha or beta decays in a given period of time and comparing with known decay rates, the abundance of a radioactive isotope may be calculated.

Mass spectrometry measures isotopic abundance by first ionizing each isotope, focusing the resulting ions into a beam, and separating them with a magnetic field according to the ratios of their mass to net electric charge. It can be used for measuring both stable and radioactive isotopes.

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