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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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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.
J. A. Lake, J. M. Kallfelz
Nuclear Science and Engineering | Volume 53 | Number 1 | January 1974 | Pages 27-46
Technical Paper | doi.org/10.13182/NSE74-A23328
Articles are hosted by Taylor and Francis Online.
Thermal-neutron energy spectra have been measured as a function of trans-verse buckling and of space position along the longitudinal axes of 25.4- × 25.4-and 35.6- × 35.6-cm beryllium assemblies by the slow-chopper, time-of-flight technique using the thermal column of the Georgia Tech Research Reactor as the steady-state neutron source. For neutrons moving in the (forward) positive Z direction, we find no evidence of the establishment of, or the tendency toward, discrete asymptotic decay conditions from the strongly space-dependent spectra in either assembly. This is a direct experimental verification of the disappearance of the discrete set of eigenvalues and eigenfunctions in the diffusion-length problem with transverse leakage. These results are in at least qualitative agreement with the transport theory predictions of Williams, but in disagreement with the diffusion theory results of Ahmed, Kothari, and Kumar which predict that a true discrete mode should exist in beryllium assemblies as small as 30 × 30 cm.