Isotopic analysis of uranium by interference spectroscopy, (2). Fabrication and performance evaluation of U-235 analyzer

A ²³⁵U enrichment analyzer based on the interference spectrometry has been designed and fabricated as compactly as possible. The analyzer is composed of an emission source, an optical system and a detection system. The source is a water cooled hollow cathode tube and a 100 mg pellet of UO₂ sample is placed in the cathode. The spectrometer of 0.5 m, a Czerny-Turner type is used with a built-in Fabry-Perot etalon. The pressure of nitrogen in the Fabry-Perot etalon is repeatedly scanned by leaking the gas through an electro-magnetic valve which is operated by the electric signal from a pressure transducer. The two-isotope components of uranium line 5,027.4Å are well separated by the etalon with a spacer thickness of 0.25cm. A relative standard deviation of 0.9 ∼ 2.2% was obtained for the samples containing 0.5 ∼ 5.0% of ²³⁵U. The relative errors of the results obtained by this analyzer were less than 1.3% for UO₂ pellets of nuclear fuels. (auth.)