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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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.
J. W. Boldeman, J. Fréhaut, R. L. Walsh
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 430-436
Technical Paper | doi.org/10.13182/NSE77-A27060
Articles are hosted by Taylor and Francis Online.
Corrections of the large liquid scintillator measurements by Boldeman et al. and Soleilhac et al. for the delayed gamma rays from fission have produced consistent values for the average number of prompt neutrons () produced in the fission of 235U. The absolute value of for thermal-neutron fission is 2.389 ± 0.009, and the energy dependence is approximately linear. The data do not support the existence of fine structure between 200 and 600 keV nor the broad step-like structural dependence found in recent evaluations. However, there is the suggestion of a slight flattening of the curve representing the data between 250 and 600 keV.
