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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.
Bernard I. Spinrad, James S. Sterbentz
Nuclear Science and Engineering | Volume 90 | Number 4 | August 1985 | Pages 431-441
Technical Paper | doi.org/10.13182/NSE85-A18491
Articles are hosted by Taylor and Francis Online.
The Wigner-Seitz cell problem is treated by integral transport theory as a superposition of black boundary problems using the volume source and sources equivalent to the two lowest order angular components of the reentrant flux. This treatment sheds light on the convergence properties of iterative integral transport solution methods. The outgoing flux is required to have the lowest order components equal and opposite to those of the reentrant flux. Sample problems with this P11 boundary condition give good results. A new approximation to neutron transport theory is also reported. This approximation does not rely on expansion or approximation of the angular flux distribution, but rather on approximating the integral transport kernel by a sum of diffusionlike kernels that preserve spatial moments of the kernel. This might permit transport problems to be treated as a set of coupled diffusion problems in any geometry.