Year
2012
Abstract
High-energy, beta-delayed gamma-ray spectroscopy is investigated as a nondestructive assay technique for the determination of plutonium mass in spent nuclear fuel. This approach exploits the unique isotope-specific signatures contained in the delayed gamma-ray emission spectra detected following active interrogation with an external neutron source. A high fidelity modeling approach that couples radiation transport, analytical decay/depletion, and a newly developed gamma-ray emission source reconstruction code are described. Results obtained up to date indicate that individual isotopespecific signatures contained in the delayed gamma-ray spectra can potentially be used to quantify the total fissile content and individual weight fractions of fissile and fertile nuclides present in spent fuel. The initial modeling results outlined in this paper suggest that Pu-239 may be assayed in a typical 17x17 PWR assembly with a statistical uncertainty of a few percent using commercially available gamma-ray spectrometers and a neutron generator with a source strength on the order of 1011 n/s.