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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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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.
Yuri Igitkhanov, Gerald Kent McCormick, Peter Eckhard Grigull
Fusion Science and Technology | Volume 46 | Number 1 | July 2004 | Pages 101-105
Technical Paper | Stellarators | doi.org/10.13182/FST04-A545
Articles are hosted by Taylor and Francis Online.
A plausible physical explanation of a new advanced high-density H (HDH)-mode operational regime on the W7-AS stellarator is discussed. The HDH regime can be achieved only under a high rate of particle fueling during the starting phase of the discharge. It can be shown that at high enough fueling rates, the density profile grows at the source position, because the relatively weaker diffusivity hinders redistribution of the plasma. This leads to formation of a density gradient at the edge and brings about the radial electric field, which suppresses the plasma turbulence [the edge transport barrier (ETB) formation]. The appearance of the ETB depends on the initial condition, i.e., on the fueling rate, but a steady-state operation depends on the average density value. This critical value can be assessed from the energy and particle balance at the edge, where the transport coefficients depend on the plasma parameters in such a way that bifurcation can occur. The bifurcation occurs between two stable solutions, which are characterized by different values of the particle flux and energy confinement time, reminiscent of the normal confinement and HDH stages. The scaling analysis shows that the threshold average density required for transition increases weakly with power and inverse aspect ratio.