A SECOND-ORDER REFOCUSING 15-INCH MASS SPECTROMETER FOR ULTRA-PRECISE ISOTOPIC RATIO MEASUREMENTS OF URANIUM HEXAFLUORIDE SAMPLES

摘要

The relationships between the precision of isotopic ratio measurements and mass spectrometer resolving power are discussed;and a high resolution mass spectrometer capable of ultra-precise isotopic ratio measurements of uranium hexafluoride samples is described. The instrument is a single-focusing, 15-inch radius, 90 degree deflection mass spectrometer. The important design features are the use of normal-circle, second-order refocusing pole boundaries and an analyzer tube geometry which exactly compensates for the effects of the magnet fringing fields.