A Computerized System for the Isotopic Analysis of Plutonium and Uranium

Rapid, accurate Pu isotopic abundance and U enrichment measurements of samples are fundamentally critical to the nuclear safeguards community. New Brunswick Laboratory is developing an improved data analysis program to realize this goal. The program, PEAKFIT, has the capability to fit a spectrum of up to 12 y-ray and X-ray peaks. The program permits the user to choose the type of background subtraction and to fix any of the seven fit parameters per peak. In addition, the user can choose to add high or low energy tails and to relate various peak parameters to each other. The program operates in one of two modes. The first technique enables frequent operator input for detailed analysis of particularly complex spectral regions. The second method comprehensively analyzes the spectrum, presenting isotopic abundance results. As a check of the program's validity, NBL compares the results acquired using PEAKFIT with the results obtained using GRPANAL and other enrichment calculations for Pu and U samples.