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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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Latest News
NRC’s David Wright visits the Hill and more NRC news
Wright
The Nuclear Regulatory Commission is in the spotlight today for three very different reasons. First, NRC Chair David Wright was on the Hill yesterday for his renomination hearing in front of the Senate’s Environment and Public Works Committee. Second, the NRC released its updated milestone schedules according to the Nuclear Energy Innovation and Modernization Act (NEIMA) and the executive orders signed by President Trump last month; and third, as reported by Reuters on Tuesday, 28 former NRC officials have condemned the dismissal of Commissioner Hanson earlier this month.
Arnaud Courcelle, Hervé Derrien, Luiz C. Leal, Nancy M. Larson
Nuclear Science and Engineering | Volume 156 | Number 3 | July 2007 | Pages 391-402
Technical Paper | doi.org/10.13182/NSE07-A2706
Articles are hosted by Taylor and Francis Online.
This paper presents a new analysis of the 238U cross sections in the unresolved resonance range, from 20 to 150 keV. Statistical analysis of the resonance parameters in the resolved resonance range with random-matrix theory provides accurate experimental values of strength function, average radiative width and average level spacing for s- and p-wave resonances. Above 20 keV, the simultaneous fit of selected experimental data (average transmission and capture) is performed with a statistical model of nuclear reactions as implemented in the SAMMY code.Compared to previous evaluations, such as those described by Fröhner or by Maslov et al., this work benefits from the accurate transmission data measured by Harvey et al. at Oak Ridge Electron Linear Accelerator, which have never been studied before. This new evaluation was written into the current ENDF format for use in practical applications. This work stresses the need for an improved ENDF format to store average resonance parameters and cross sections in the unresolved resonance range.