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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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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.
L. C. Leal, H. Derrien, N. M. Larson, R. Q. Wright
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 230-253
Technical Paper | doi.org/10.13182/NSE99-A2031
Articles are hosted by Taylor and Francis Online.
A new R-matrix analysis of the 235U cross-section data in the 0- to 2250-eV energy region is presented. The analysis was performed with the SAMMY computer code that has recently been updated to permit, for the first time, inclusion of both differential and integral data within the analysis process. Fourteen differential data sets and six integral quantities were used in this evaluation: two measurements of fission plus capture, one of fission plus absorption, six of fission alone, two of transmission, and one of eta, plus standard values of thermal cross sections for fission and capture, and of K1 and the Westcott g factors for both fission and absorption. An excellent representation was obtained for the high-resolution transmission, fission, and capture cross-section data as well for the integral quantities. The result is a single set of resonance parameters spanning the entire range up to 2250 eV, a decided improvement over the present ENDF/B-VI evaluation, in which 11 discrete resonance parameter sets are required to cover that same energy range. This new evaluation is expected to greatly improve predictability of the criticality safety margins for nuclear systems in which 235U is present.