Isotope analysis

摘要

The difference in concentration of a selected isotope in two materials is measured by directing beams of the materials toward the inlet of a mass spectrometer. A shutter is positioned in each beam to pass the two beams at predetermined different frequencies. The output signal from the mass spectrometer is applied to two synchronous detectors, each of which receives a reference signal representative of the frequency at which a respective beam is passed to the mass spectrometer. The output signals from the two detectors are compared.