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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Yasunori Yamamura, Hiroshi Kimura
Nuclear Science and Engineering | Volume 58 | Number 1 | September 1975 | Pages 98-103
Technical Note | doi.org/10.13182/NSE75-A26771
Articles are hosted by Taylor and Francis Online.
With the help of the generalized function theory, the macroscopic treatment of neutrons slowing down in a homogeneous medium is investigated. As a result, it is found that the balance equation for neutron flux is exactly expressed by for a monoenergetic source as well as a fission source, where the moderating parameter is defined as the ratio of slowing down density to collision integral .Source dependence of this parameter, (u), is also examined analytically and numerically. In the transient region the difference of (u)’s for a monoenergetic source and a fission source is shown to be remarkable. For a monoenergetic source the asymptotic value is found to be a monotonically decreasing function of the absorbing ratio, a, while the of fission neutrons is also a decreasing function for the smaller absorbing ratio than a certain critical absorbing ratio and for large a it has the constant value .