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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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.
D. G. Cacuci, J.J. Wagschal, A. Yaari
Nuclear Science and Engineering | Volume 81 | Number 3 | July 1982 | Pages 443-450
Technical Paper | doi.org/10.13182/NSE82-A20285
Articles are hosted by Taylor and Francis Online.
The concept of a leakage importance function is introduced and analyzed for physical systems governed by the Boltzmann transport equation. The homogeneous equation with inhomogeneous boundary conditions satisfied by the importance function is derived by using adjoint operators. A standard discrete ordinates transport code is used to solve this equation, and some important numerical aspects are highlighted. Idealized nuclear systems are analyzed to illustrate that the leakage importance function gives a measure of the relative importance of each source particle in phase space in contributing to the leakage, and that the leakage importance function provides insight regarding the specific physical process that leads to leakage.
