Analysis of Confirmation Measurement Data for Global Threat Reduction Initiative (GTRI) Recovery Program

National Nuclear Security Administration’s (NNSA) Global Threat Reduction Initiative (GTRI) aims to recover and secure attractive nuclear material throughout the world in support of nuclear nonproliferation. In support of this mission, the Y-12 National Security Complex (Y-12) recently executed an international recovery of U.S. origin highly enriched uranium (HEU). The HEU was in the form of uranium-aluminum fabrication scraps and uranium oxides. Traditional confirmation measurements of this material are difficult because the material is not in a standardized form. To resolve this difficulty, NaIGEM software is used to analyze sodium iodide (NaI) spectra with additional correction factors applied to compensate for the unique characteristics of the material. An estimation of the enrichment was calculated and compared with the declared value. This paper will present the details of these calculations.