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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.
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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.
Charles N. Kelber and Philip H. Kier
Nuclear Science and Engineering | Volume 26 | Number 1 | September 1966 | Pages 67-72
Technical Paper | doi.org/10.13182/NSE66-A17188
Articles are hosted by Taylor and Francis Online.
A model is developed for the estimation of the Doppler effect from the unresolved energy region for fissile nuclides. For energy intervals that contain enough resonances for the reaction rates to be statistically independent of neighboring intervals, many resonance structures, or ladders, are generated by a random process that preserves the average widths and strength function. For each ladder, the relative changes in the absorption and the fission rates with temperature are computed, including overlap effects. This procedure yields estimates of mean quantities and the dispersion of values about the mean when the reaction rates are regarded as random variables. The Doppler effect and its variance are obtained by incorporating these resonance integral calculations into a multigroup-perturbation theory formulation., This model has been used to estimate the Doppler effect for 239Pu in the Codd and Collins mixture. For a temperature change from 300 to 600°K, the contributions to Ak/k from the unresolved region (215 eV to 10 keV) and the resolved region ( < 215 eV) were calculated to be 290 X 10"6 and 440 X10-6, respectively. The probable error, or ^2/3 standard deviation in the Doppler effect, assumed to be solely from the unresolved region, was ± 290 X 10" 6.