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Nuclear Criticality Safety
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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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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.
M. M. Bretscher, W. C. Redman
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 368-378
Technical Paper | doi.org/10.13182/NSE70-A19997
Articles are hosted by Taylor and Francis Online.
The effective capture-to-fission ratio has been measured for 239Pu and 235U in a low flux fast-reactor spectrum by the reactivity-reaction-rate technique. A 252Cf source and a 6Li absorber were used to measure the relative importance of fission and absorbed neutrons, respectively. The measurements were made in Assembly 24 of ZPR-9 which was designed to produce a neutron spectrum that emphasized fission and capture events in the 0.1 to 25 keV range. For 239Pu and 235U the measured values, corrected to infinite sample dilution, were 0.516 ± 0.040 and 0.337 ± 0.029, respectively. Corresponding integral alpha values calculated from ENDF/B were 0.352 and 0.346. The experimental value for 239 is in reasonable agreement with calculations based on recent differential data obtained by both the Oak Ridge-Rensselaer and the United Kingdom groups. These calculations yielded 239Pu alpha values of 0.466 (ORNL-RPI) and 0.471 (UK).
