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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.
C. B. Bigham
Nuclear Science and Engineering | Volume 59 | Number 1 | January 1976 | Pages 50-52
Technical Note | doi.org/10.13182/NSE76-A26808
Articles are hosted by Taylor and Francis Online.
The fission cross sections for 233U, 235U, 239Pu, and 241Pu reported in 1958 have been revised using the very precise, recently published, specific activities 21 405 ± 20 dpm/µg 233U, 4798.1 ± 3.3 dpm/mg 235U, and 746.19 ± 0.41 dpm/mg 238U. Revised ratios of fission cross sections at 2200 m/sec are: 233U/235U = 0.9142 ± 0.0012, 239Pu/235U = 1.2876 ± 0.0034, 239Pu/ 233U = 1.4084 ± 0.0036, and 241Pu/239Pu = 1.3506 ± 0.007. Revised fission cross sections at 200 m/sec in barns relative to σc(197 Au) = 98.7 ± 0.2 are: σf(233 U) = 527.4 ± 3.1 σf(235 U) = 576.9 ± 3.4, σf(239 Pu) = 742.8 ± 4.4, and σf(241 Pu) = 1003.3 ± 5.2. The errors do not include g-factor errors of ±0.2% for 233U, ±0.155% for 235U, ±0.285% for 239Pu, and ±0.7% for 241Pu.
