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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.
Fong-Yan Gang, D. J. Sigmar, Jean-Noel Leboeuf, Fredrik Wising
Fusion Science and Technology | Volume 25 | Number 3 | May 1994 | Pages 266-277
Technical Paper | Alpha-Particle Special / Plasma Engineering | doi.org/10.13182/FST94-A30283
Articles are hosted by Taylor and Francis Online.
Recent developments in computational and theoretical studies of alpha-particle-driven Alfvén turbulence in both the long (k⊥ρi ≪ 1) and the short (k⊥ρi ≤ 1) wavelength regimes are reported. In the long wavelength regime, a hybrid particle-fluid model is solved numerically as well as analytically in a simple slab geometry. The dominant nonlinear interactions are found to be couplings between two Alfvén waves to generate a zero-frequency electromagnetic convective cell and strong E × B convection of resonant alpha particles, which result in significant changes in plasma equilibria. The fluctuation energies first increase, then saturate and decay. The alpha-particle transport is convective and significant but does not necessarily lead to an appreciable alpha-particle loss. A mode-coupling theory is developed to explain the simulation results. In the short wavelength regime, a reduced turbulence model that describes the coupled nonlinear evolutions of fluctuation spectrum and alpha-particle density profile nα(r,t) in the presence of an alpha-particle source Sα(r, t) is solved numerically. A steady state is achieved. The nonlinear saturation is due to ion Compton scattering-induced energy transfer to higher wave numbers. Alpha-particle transport is significant, and a diffusion coefficient of Dα ≃ 0.5 m2/s for International Thermonuclear Experimental Reactor (ITER)-like parameters is obtained. The effect of anomalous alpha-particle diffusion on alpha-particle power coupling to bulk plasmas is also discussed.