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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
F. D. Judge and P. B. Daitch
Nuclear Science and Engineering | Volume 26 | Number 4 | December 1966 | Pages 472-486
Technical Paper | doi.org/10.13182/NSE66-A18418
Articles are hosted by Taylor and Francis Online.
The variational method is used to reduce the general time-dependent Boltzmann equation to a multigroup (with overlapping or nonoverlapping) form. The variation of the fundamental decay rate with material properties is then studied. The relation between energy and space transients in pulsed multiplying and pulsed moderating systems is investigated. To augment the theoretical treatment of the asymptotic decay in a pulsed multiplying system, the Nelkin buckling expansion solution for the Fourier transformed transport equation for 1/υ absorption is extended to include non-1/υ absorption and fission. The development of an improved calculational procedure (DP-L multigroup overlapping or nonoverlapping) for determining the space and time dependence of the neutron flux in pulsed multiplying systems is described. This method is then applied to the analysis of recent pulsed spectra measurements. The duration of the energy and spatial transients and the variation of the vector flux distribution from the center to the edge of an assembly are described quantitatively. It is demonstrated that spatial asymmetries in the flux could exist after the flux distribution appears asymptotic.
