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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.
K. M. Case, Joel H. Ferziger, P. F. Zweifel
Nuclear Science and Engineering | Volume 10 | Number 4 | August 1961 | Pages 352-356
doi.org/10.13182/NSE61-A15377
Articles are hosted by Taylor and Francis Online.
It is first shown that the results of “asymptotic reactor theory” may be derived simply from the condition that an infinite medium rather than the correct finite medium diffusion equation be used to describe the thermal neutron flux in a reactor. In an asymptotic (bare, homogeneous, thermal) reactor, it is possible to describe the thermal flux through such an equation if the kernel of the infinite medium equation is defined properly, even when the reactor is not “large.” The relation between the kernels of the two equations is explicitly derived, and the conditions examined under which the kernel of the infinite medium equation can be interpreted physically as the Green's function of the infinite medium slowing-down problem. It is found that this interpretation is not restricted to the case in which the finite medium, slowing-down problem can be treated accurately by diffusion theory. Rather, the restriction is that the “asymptotic” portion of the flux give a reasonably accurate description of the finite medium Green's function. Thus, the use of transport kernels in asymptotic reactor theory is meaningful, a result which has been observed, but not explained, by a number of authors.