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Division Spotlight
Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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.
Marc A. Cooper, Edward W. Larsen
Nuclear Science and Engineering | Volume 137 | Number 1 | January 2001 | Pages 1-13
Technical Paper | doi.org/10.13182/NSE00-34
Articles are hosted by Taylor and Francis Online.
A new method for efficiently solving global Monte Carlo particle transport problems is presented. (In these problems, flux information is desired across the entire system, not just at a small number of detector locations.) The method is based on the use of a weight window that distributes Monte Carlo particles uniformly throughout the system. This (a) ensures that all subregions of the system are adequately sampled and (b) controls the particle weights, even in subregions far from sources. The weight window is constructed from an approximate deterministic solution of the forward transport problem. It is argued that a weight window based on the forward transport solution is more appropriate for global problems than the more familiar concept of basing a weight window on an adjoint solution for source-detector problems. It is also shown that by using Monte Carlo-generated Eddington factors in deterministic solutions of the quasi-diffusion equation, one can inexpensively compute updated forward-based weight windows and obtain a more efficient global Monte Carlo calculation.