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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
O. Bouland, H. Derrien, N. M. Larson, L. C. Leal
Nuclear Science and Engineering | Volume 127 | Number 2 | October 1997 | Pages 105-129
Technical Paper | doi.org/10.13182/NSE127-105
Articles are hosted by Taylor and Francis Online.
A Bayesian R-matrix-fitting code called SAMMY is used in a new analysis of the 240Pu neutron cross sections in the 0.02- to 5700-eV energy range. This work aims to resolve the discrepancies revealed by the JEF2 validation studies. A set of experimental data, suitable for the analysis, is determined from preliminary SAMMY analyses of the available experimental data treated individually. Finally, the sequential analysis of the selected transmission, total, and fission cross-section measurements gives an accurate set of resonance parameters. For the 1.056-eV resonance, the analysis of a recent transmission measurement gives parameters very close to those adopted in ENDF/B-VI. In the energy range above 200 eV, the average capture cross section calculated from the present evaluation is in agreement with ENDF/B-VI but is 25% lower than the values of JEF-2 and JENDL-3. A rigorous study of the statistical properties of the resonance parameters is done during this work. Although 158 new resonances are identified by the careful examination of the experimental fission cross-section and transmission data, the value of the average spacing above 2750 eV (D0 = 16.10 eV) shows a 25% loss of resonances compared with the lower energy region (D0 = 12.06 eV). Finally, for the s-wave resonance parameters, this work recommends the following average values: resonance spacing, D0 = 12.06 ± 0.60 eV; strength function, S0 = (1.032 ± 0.071) × 10−4 eV; and capture width, = 31.92 ± 1.6 meV.
