Year
1994
Abstract
A criteria that a sample of highly enriched uranium (HEU) had come from a weapons stockpile and not newly produced in an enrichment plant is to show that the HEU had been produced a significant time in the past. The time since the HEU was produced in an enrichment plant is defined as the age of the HEU in this paper. The HEU age is determined by measuring quantitatively the daughter products and 231Pa of 234U and 235U, respectively, by first chemical separation of the thorium and protactinium and then conducting alpha spectrometry of the daughter products .