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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
G. Noguere, D. Bernard, P. Blaise, O. Bouland, L. Leal, P. Leconte, O. Litaize, Y. Peneliau, B. Roque, A. Santamarina, J.-F. Vidal
Nuclear Science and Engineering | Volume 182 | Number 2 | February 2016 | Pages 135-150
Technical Paper | doi.org/10.13182/NSE15-9
Articles are hosted by Taylor and Francis Online.
An overestimation of the keff values for mixed oxide (MOX) fuels was identified with Monte Carlo (TRIPOLI-4) and deterministic (APOLLO2) calculations based on the Joint Evaluated Fission and Fusion (JEFF) evaluated nuclear data library. The overestimation becomes sizeable with Pu aging, reaching a reactivity change of Δρ≈+700 pcm for integral measurements carried out with MOX fuel containing a large amount of americium. This bias was observed for various critical configurations performed in the zero-power reactor EOLE of the Commissariat à l’énergie atomique et aux énergies alternatives (CEA), Cadarache, France. The present work focuses on the improvements achieved with the new 239Pu and 241Am evaluated nuclear data files available in the latest version of the JEFF library (JEFF-3.2). The resolved resonance range of the plutonium evaluation was reevaluated at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee, with the SAMMY code in collaboration with CEA Cadarache. The resonance parameters of the americium evaluation were obtained with the REFIT code in collaboration with the research institutes Institute for Reference Materials and Measurements (IRMM), Geel, Belgium, and Institut de recherche sur les lois fondamentales de l’Univers (Irfu), Saclay, France.