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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
Meeting Spotlight
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
Standards Program
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.
M. J. Ohanian, R. S. Booth, R. B. Perez
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 95-103
Technical Paper | doi.org/10.13182/NSE67-A17246
Articles are hosted by Taylor and Francis Online.
Neutron-wave propagation in moderating media is investigated within the framework of the diffusion approximation to the Boltzmann equation, using a realistic scattering model and the eigenfunction expansion method. The eigenfunctions are obtained from the thermalization theory solution to the exponential experiment with their corresponding eigenvalues being the fundamental and higher diffusion lengths of the medium. Expanding the energy dependence of the neutron-wave problem in these eigenfunctions leads to a simpler and more accurate secular determinant than that obtained from a Laguerre polynomial expansion. Solving the secular determinant yields the squared complex inverse relaxation lengths for the asymptotic energy mode and for the continuum energy modes. A discrete energy formulation, Simpson's rule integration scheme, and the Jacobi method of matrix diagonalization are used in the numerical solution to the eigen-value problem. The dispersion law for graphite, obtained by direct solution of the complex secular determinant, is compared with experimental results. This investigation indicates that high-energy-mode contamination will not seriously affect neutron-wave experiments in graphite in the frequency range where diffusion and thermalization parameters can be obtained.