Direct measurement of ~(235)U in spent fuel rods with Gamma-ray mirrors

摘要

Direct measurement of plutonium and uranium X-rays and gamma-rays is a highly desirable nondestructive analysis method for the use in reprocessing fuel environments. The high background and intense radiation from spent fuel make direct measurements difficult to implement since the relatively low activity of uranium and plutonium is masked by the high activity from fission products. To overcome this problem, we make use of a grazing incidence optic to selectively reflect K_α and K_β fluorescence of Special Nuclear Materials (SNM) into a high-purity position-sensitive germanium detector and obtain their relative ratios.