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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.
J. A. Bucholz
Nuclear Science and Engineering | Volume 74 | Number 3 | June 1980 | Pages 163-167
Technical Paper | doi.org/10.13182/NSE80-A20115
Articles are hosted by Taylor and Francis Online.
Many detailed multigroup transport calculations require group-to-group Legendre transfer coefficients to represent scattering processes in various nuclides. These (fine group) constants must first be generated from the basic data. This paper outlines an alternative technique for generating such data, given the total scattering cross section of a particular nuclide on a point-wise energy basis, σ(E'), and some information regarding the angular scattering distribution for each initial energy point. The evaluation of generalized multigroup transfer matrices for transport calculations requires a double integration extending over the primary and secondary energy groups where, for a given initial energy, the integration over the secondary energy group may be replaced by an integral over the possible scattering angles. In the present work, analytic expressions for these angular integrals are derived that are free of truncation error. Differences between the present method (as implemented in ROLAIDS) and other methods (as implemented in MINX and XLACS-2) will be explored. Of particular interest is the fact that, for hydrogen, the angular integration is shown to simplify to the point that, for many weight functions, the integration over the primary energy group might also be performed analytically. This completely analytic treatment for hydrogen has recently been implemented in NEWXLACS.