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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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March 2025
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Fusion Science and Technology
February 2025
Latest News
WEST claims latest plasma confinement record
The French magnetic confinement fusion tokamak known as WEST maintained a plasma in February for more than 22 minutes—1,337 seconds, to be precise—and “smashed” the previous record plasma duration for a tokamak with a 25 percent improvement, according to the CEA, which operates the machine. The previous 1,006-second record was set by China’s EAST just a few weeks prior. Records are made to be broken, but this rapid progress illustrates a collective, global increase in plasma confinement expertise, aided by tungsten in key components.
T. Wakabayashi, Y. Hachiya
Nuclear Science and Engineering | Volume 63 | Number 3 | July 1977 | Pages 292-305
Technical Paper | doi.org/10.13182/NSE77-A27041
Articles are hosted by Taylor and Francis Online.
The thermal-neutron behavior in a highly heterogeneous cluster-type plutonium fuel lattice has been studied through the measurements of the dysprosium reaction-rate distribution in a unit cell covering three plutonium fuel elements, four coolant voids, and two lattice pitches. The study included comparison with the results obtained with UO2 fuel. A new technique for locating the foils has been developed, resulting in an accurate measurement of the thermal-neutron flux distribution. Depression of the thermal-neutron flux in the fuel region is larger in the plutonium fuel lattice than in the uranium lattice because thermal-neutron absorption in the plutonium fuel is enhanced by the resonances of 239Pu and 241Pu at 0.3 eV. In addition, the 1/v cross section of plutonium is larger than that of uranium. This property of the plutonium fuel appears markedly at 100% void fraction, but less at 0% because this property is weakened by the presence of H2O coolant. The results of calculations obtained by means of the LAMP-DCA code showed good agreement with experimentally determined data within 5%.
