Gamma-spectrometric determination of 232U in uranium-bearing materials

TL;DR

This paper presents a gamma spectrometry method for measuring 232U in uranium materials that is independent of sample geometry and composition, aiding nuclear forensics and safeguards by linking 232U content to irradiation history.

Contribution

The study introduces a geometry-independent gamma spectrometry technique for 232U detection and establishes a correlation between 232U content and 235U enrichment for material discrimination.

Findings

Established a correlation between 232U content and 235U enrichment.

Demonstrated the method's independence from measurement geometry.

Showed how to distinguish reprocessed uranium materials.

Abstract

The 232U content of various uranium-bearing items was measured using low-background gamma spectrometry. The method is independent of the measurement geometry, sample form and chemical composition. Since 232U is an artificially produced isotope, it carries information about previous irradiation of the material, which is relevant for nuclear forensics, nuclear safeguards and for nuclear reactor operations. A correlation between the 232U content and 235U enrichment of the investigated samples has been established, which is consistent with theoretical predictions. It is also shown how the correlation of the mass ratio 232U/235U vs. 235U content can be used to distinguish materials contaminated with reprocessed uranium from materials made of reprocessed uranium.