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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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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.
Robert P. Rulko, Edward W. Larsen
Nuclear Science and Engineering | Volume 114 | Number 4 | August 1993 | Pages 271-285
Technical Paper | doi.org/10.13182/NSE93-A24040
Articles are hosted by Taylor and Francis Online.
Even-order PN theory has historically been viewed as a questionable approximation to transport theory. The main reason is that one obtains an odd number of unknowns and equations; this causes an ambiguity in the prescription of boundary conditions. We derive the one-group planar-geometry P2 equations and associated boundary conditions using a simple, physically motivated variational principle. We also present numerical results comparing P2, P1, and SN calculations. These results demonstrate that for most problems, the P2 equations with variational boundary conditions are considerably more accurate than the P1 equations with either the Marshak or the Federighi-Pomraning boundary conditions (both of which have also been derived variationally). Moreover, because the P2 and P1 equations can be written in diffusion form, the discretized P2 equations require nearly the same computational effort to solve as the discretized P1 equations. Our variational method can easily be extended to higher even-order PN approximations.