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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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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
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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.
D. R. Harris
Nuclear Science and Engineering | Volume 21 | Number 3 | March 1965 | Pages 369-381
Technical Paper | doi.org/10.13182/NSE65-A20040
Articles are hosted by Taylor and Francis Online.
Fluctuations of the neutron populations in various phase-space regions in a reactor have been examined by development of a three-step analysis. First, the usual transport equation, or an approximation to it, is used to compute the probability that a neutron injected at a certain location in the reactor gives rise to a chain-related descendant neutron in each of a number of differential volume elements in phase space. Second, these conditional probabilities are used to compute product densities, probabilities that nuclear reactions of a certain class are induced in various time intervals by neutrons in each of a number of differential volume elements. Finally, the product densities are used to compute local population moments, parameters arising in the Rossi alpha experiment, auto- and cross-correlation functions, and other quantities of interest in fluctuation studies. The analysis, as applied to various reactor geometries, shows that the usual point-reactor analysis of reactor neutron fluctuations can lead to substantial error in predicting fluctuation magnitudes in startup studies and in determination of some reactor parameters from fluctuation experiments.