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Division Spotlight
Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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.
G. Robert Keepin
Nuclear Technology | Volume 14 | Number 1 | April 1972 | Pages 53-58
Technical Paper | Session on Physics of Nuclear Materials Safeguards / Reactor | doi.org/10.13182/NT72-A31097
Articles are hosted by Taylor and Francis Online.
In connection with the U.S. Atomic Energy Commission’s nuclear safeguards research and development (R&D) program, measurements of absolute delayed-neutron yields as a function of energy of the neutron inducing fission have been carried out at the Los Alamos Scientific Laboratory on 239Pu, 233U, 235U, 238U, 232Th, and 242Pu. The observed constancy of delayed-neutron yield for neutron energies up to ∼4 MeV brings important advantages to the practical application of delayed-neutron techniques for quantitative assay of fissionable materials. Also reported are delayed-neutron half-lives and group abundances in 14.7-MeV fission of 233U, 235U, and 238U. Measured delayed-neutron characteristics are discussed in terms of yield systematics, fission mass and charge distributions, and their dependence on energy of the neutron inducing fission.
