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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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.
Scott D. Ramsey, Roy A. Axford, Gregory J. Hutchens
Nuclear Science and Engineering | Volume 166 | Number 1 | September 2010 | Pages 73-81
Technical Note | doi.org/10.13182/NSE09-63TN
Articles are hosted by Taylor and Francis Online.
Stochastic point kinetics neglecting delayed neutrons has been subject to rigorous analysis in the years since its introduction. Many approximate solutions appearing within this context are based upon the “quadratic approximation,” where fission multiplicity is truncated at two. In this technical note we review the quadratic approximation within the context of a stochastic, space-independent, one-energy-group model neglecting delayed neutrons and its generalization to higher-order approximations in transient and stationary systems. This generalization results in the probability of a zero neutron population for a source-free system being governed by transcendental and polynomial algebraic equations in the transient and infinite time limit cases, respectively. For 239Pu, we solve the transcendental equation over a wider range of prompt multiplication factors and times than has been previously accomplished. We also reproduce and generalize associated solutions of the polynomial algebraic equation. In both cases, solutions are computed for successive generalizations of the quadratic approximation to higher-order maximum fission multiplicity.