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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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Dwight W. Underhill
Nuclear Technology | Volume 8 | Number 3 | March 1970 | Pages 255-260
Paper | Fuel | doi.org/10.13182/NT70-A28672
Articles are hosted by Taylor and Francis Online.
Exact equations for the experimental analysis of fission-gas holdup beds are developed by the method of statistical moments. The mean retention time, given by the first moment, is independent of the factors which affect mass transfer. This independence emphasizes the important fact, sometimes overlooked in the analysis of fission-gas holdup beds, that the true dynamic adsorption coefficient for a stable fission-gas isotope is identical to the static adsorption coefficient. The second moment, used in combination with the first moment, describes the spreading of the input after it has passed through the holdup bed. The meaning of these equations is examined in detail, and by their correct use the factors needed for the design of fission-gas holdup beds can be determined rapidly from laboratory experiments. This method of analysis is applied to data obtained from fronts of dilute 85Kr passed through charcoal beds.
