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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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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.
F. D. Judge, P. B. Daitch
Nuclear Science and Engineering | Volume 20 | Number 4 | December 1964 | Pages 428-435
Technical Paper | doi.org/10.13182/NSE64-A20984
Articles are hosted by Taylor and Francis Online.
The one-dimensional (slab), one-velocity time-dependent transport equation has been investigated using a variational method employing flat spatial trial functions. A simple approximation is found for the variation of the asymptotic decay rate (α) with slab size for small slabs. As expected, little difference is found between the use of a single flat spatial flux trial function and a double stepped flux trial function for thin slabs. The method is then extended to the case of a convex body of arbitrary shape. It is shown that an estimate for α is given by the relation where Pc = first collision probability. For the slab case, an effective spatial buckling and an effective extrapolation distance consistent with the exact asymptotic decay constant were obtained. This extrapolation distance is approximately equal to the Milne problem value down to a scattering thickness of about 1.0 mean free path after which it rises to λs for the limiting case of zero thickness. Finally, asymptotic time decay rates based upon low-order PL and DPL approximations in slab geometry are determined either numerically or from the exact analytical solutions; a real eigenvalue may or may not exist depending on the boundary conditions. It is shown further that these low-order approximations yield erroneous time-dependent characteristics in the thin slab limit.