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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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X-energy receives federal tax credit for TRISO fuel facility
Advanced reactor company X-energy has been awarded $148.5 million in tax credits under the Inflation Reduction Act for construction of its TRISO-X fuel fabrication facility in Oak Ridge, Tenn.
P. Saracco, G. Ricco
Nuclear Science and Engineering | Volume 162 | Number 2 | June 2009 | Pages 167-177
Technical Note | doi.org/10.13182/NSE162-167
Articles are hosted by Taylor and Francis Online.
We present a model of a subcritical neutron multiplying system coupled to an external time-dependent neutron source, within one-group diffusion theory. Within this scheme we show that the problem is fully solvable without any other approximation. Then, we are able to show that all the known results about such systems can be consistently derived. In such a way we are able to discuss various specific aspects that distinguish a subcritical system from a critical one without relying on any other approximations or assumptions. Moreover, we prove that a subcritical system has very different working regimes as the level of subcriticality varies.