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Reactor Physics
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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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
Carlos Gago B.
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 55-64
Technical Paper | doi.org/10.13182/NSE79-A21285
Articles are hosted by Taylor and Francis Online.
It is shown that Fick's law can be used in the calculation of the rigorous neutron slowing down length for hydrogenous moderators (or in fact for any moderator), provided that the corresponding diffusion coefficient is determined within the set of equations of the consistent P1 approximation. For a given moderator, this coefficient depends solely on lethargy and source spectrum and therefore can be evaluated prior to an actual numerical calculation, which can then be carried out within the simplicity of a diffusion approximation. Furthermore, the flux calculated in this way essentially agrees with the consistent P1 result in all regions where this approximation is justified. The practical generalization to nonhydrogenous moderators is carried out by means of the Goertzel-Greuling procedure.