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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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
R. Böhme, H. Seufert
Nuclear Technology | Volume 7 | Number 6 | December 1969 | Pages 494-504
Reactor | doi.org/10.13182/NT69-A28368
Articles are hosted by Taylor and Francis Online.
An absolute determination of uranium reaction rates by means of foil irradiation was carried out in the Fast Zero Power Reactor SNEAK, assembly 3A-2 This requires the measurement of reactionrate traverses as well as their fine structure. These rate distributions were compared with transport and diffusion calculations. The traverse measurements indicate a strong dependence of the axial “buckling” (relative second derivative of the rates) on energy. The calculations with the Karlsruhe SNEAK cross-section set and the Russian ABN set yield these bucklings for 238U capture and 235U fission in diffusion approximation on the average 5% higher than measured. Only the fast-fission rate distribution of 238U is almost correctly calculated using the cross-section sets. The ratio of total plutonium production to 235u fission along the z axis was measured and compared with theory. It agrees within the error limits of the experiment. Beyond the error limits are the discrepancies found for the spectral index σƒ28/σƒ25 The fine structure of reaction rates within the fuel platelets is well described by an integral transport code, but again, there are considerable discrepancies between calculated and measured fission-rate ratios.
