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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.
Harvey J. Amster, M. Jahed Djomehri
Nuclear Science and Engineering | Volume 60 | Number 2 | June 1976 | Pages 131-142
Technical Paper | doi.org/10.13182/NSE76-A26869
Articles are hosted by Taylor and Francis Online.
Successive solutions to two coupled integral equations provide the expected statistical error of any Monte Carlo calculation in which the external source is specified and the “score” resulting from each collision has a known probability distribution. Each equation can be transformed into a differential-integro form that is adjoint to the transport equation. This result agrees with the stochastic theory of Bell for those special situations described by both theories. The coupled integral equations in the Monte Carlo theory of Coveyou et al. have other adjoint properties because they describe physically different quantities. In the present theory, the first equation (for the expected value), but not the second (for the expected squared value), can readily be understood in terms of Selengut's general interpretation of adjoint solutions. The principal aim of this work is to provide a method for determining in advance whether or not development of a contemplated Monte Carlo program would be worthwhile. Any of the approximations commonly applied to the transport equation can be used. Some examples are worked out by diffusion theory, interpreted, and tested for accuracy.