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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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. C. Larson
Nuclear Science and Engineering | Volume 78 | Number 4 | August 1981 | Pages 324-332
Technical Paper | doi.org/10.13182/NSE81-A21366
Articles are hosted by Taylor and Francis Online.
The 23Na(n,2n) reaction produces the radioactive product 22Na, with a half-life of 2.61 years. For sodium-containing systems this reaction can result in a radioactive contamination problem. Currently available experimental cross sections for this reaction are in strong conflict. Comprehensive nuclear model calculations performed as part of the sodium evaluation for ENDF/B-V are in agreement with one of the experimental data sets. Acceptance of this data set results in an (n,2n) cross section larger than was given in ENDF/B-IV by ∼37% at 15 MeV and by as much as a factor of 4 at 20 MeV.