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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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
R. N. Hwang
Nuclear Science and Engineering | Volume 56 | Number 2 | February 1975 | Pages 119-130
Technical Paper | doi.org/10.13182/NSE75-A26651
Articles are hosted by Taylor and Francis Online.
This paper describes some general characteristics of the uncertainties in various fast-reactor parameters as a function of the corresponding uncertainties in nuclear data on the basis of statistical theory. By using the variational formalism, it is possible to relate the mean-square deviation of any reactivity coefficient (or reaction-rate ratio) to the covariance matrix of cross sections. The qualitative behavior of the uncertainties in fast-reactor parameters can be best illustrated geometrically in terms of the region of tolerance. The latter is the volume bound by a “hyper-ellipsoid” surface specified by the designer’s tolerance limit, the coefficients characteristic of the type of parameter in the system under consideration, and the correlation matrix. Exploratory studies and graphical illustrations are given for some cases of practical interest.
