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Division Spotlight
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.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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
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.
G. Th. Analytis, J. K.-H. Karlsson {ti}Spatial Neutronic Decoupling of Large Fast Breeder Reactor Cores: Application to Nuclear Core Design Method
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 286-292
Technical Note | doi.org/10.13182/NSE99-A2036
Articles are hosted by Taylor and Francis Online.
It is well known that after one of the spatial harmonics of a boiling water reactor (BWR) is driven toward limit-cycle oscillations with a decay ratio very close to 1, the nonlinear behavior of the system starts to manifest itself, and a series of resonances appears at frequencies that are multiples of the characteristic oscillation frequency (commonly called harmonic frequencies). Several such resonances have been clearly identified during measurements in BWRs during which the system is in the unstable, limit-cycle oscillations regime. The ability to identify three and possibly four of these harmonic resonance peaks in the neutron spectra of Ringhals-1 is reported. For the measurements to be analyzed, these resonances are due to the limit-cycle oscillations not of the fundamental but of the first spatial harmonic of the neutron flux.