Plutonium and uranium isotopic analysis: recent developments of the MGA++ code211 suite

摘要

The Lawrence Livermore National Laboratory develops sophisticated gamma-ray211u001eanalysis codes for isotopic determinations of nuclear materials based on the 211u001eprinciples of the MultiGroup Analysis (MGA). MGA methodology has been upgraded 211u001eand expanded and is now comprised of a suite of codes known as MGA++. A graphical 211u001euser interface has also been developed for viewing the data and the fitting 211u001eprocedure. The code suite provides plutonium and uranium isotopic analysis for 211u001edata collected with high-purity germanium planar and/or coaxial detector systems. 211u001eThe most recent addition to the MGA++ code suite, MGAHI, analyzes Pu data using 211u001ehigher-energy gamma rays (200 keV and higher) and is particularly useful for Pu 211u001esamples that are enclosed in thick-walled containers. Additionally, the code 211u001esuite can perform isotopic analysis of uranium spectra collected with cadmium-211u001ezinc-telluride (CZT) detectors. We are currently developing new codes with will 211u001eintegrate into the MGA++ suite. These will include Pu isotopic analysis 211u001ecapabilities for data collected with CZT detectors, and U isotopic analysis with 211u001ehigh-purity germanium detectors, which utilizes only higher energy gamma rays. 211u001eFuture development of MGA++ will include a capability for isotopic analyses on 211u001emixtures of Pu and U.