URANIUM STANDARDS FOR THE Y-12 NUCLEAR DETECTION AND SENSOR TESTING CENTER

Enriched and Highly Enriched Uranium (EU – HEU) standards have been fabricated for use in the Nuclear Detection and Sensor Testing Center (NDSTC) at the Y-12 National Security Complex. The initial set of EU – HEU standards produced for NDSTC was funded by the National Nuclear Security Administration (NNSA) Nonproliferation and International Security’s Office of Nuclear Verification (NA-243). These uranium standards range from 3% to 93% percent 235U and all are comprised of metallic uranium. Currently, there are 4 standards containing 3%, 19.4%, 54.9% and 93.2% 235U. Gamma spectra of these standards are being collected at Y-12 using different types of gamma-ray spectrometry systems including High Purity Germanium (HPGe), Cadmium Zinc Telluride (CZT), Lanthanum Bromide (LaBr3), and Sodium Iodide (NaI[Tl]) detector systems. Measurements have also been taken in a variety of shielding configurations in order to create a catalog of reference spectra. More standards with additional 235U enrichments are planned and these standards also will be available at NDSTC for measurements. These EU – HEU standards shall be well characterized for isotopic abundances and detailed chemical compositions. This site of NDSTC is available to researchers with and without security clearances; e.g., from National Laboratories, universities, and nuclear instrumentation companies. Input is sought from the user community on future needs of the facility, including equipment, shielding/reflectors, and standards. Photographs and gamma-ray spectra of the current uranium standards, as well as plans for future work, will be presented.