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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.
Arthur H. Snell
Nuclear Science and Engineering | Volume 90 | Number 4 | August 1985 | Pages 358-366
Technical Paper | doi.org/10.13182/NSE85-A18480
Articles are hosted by Taylor and Francis Online.
An account is given of some nuclear measurements that apparently had some importance in the early days of the nuclear chain reaction. These include measurements of the decay periods and the intensity of the delayed neutrons (important for the control of the chain reaction), and the first measurements relative to a fast-neutron chain reaction in uranium metal. The latter showed that normal uranium would have to be enriched by a factor of more than 12 in order to sustain a fast-neutron chain reaction in a finite geometry, and that high enrichment would be needed for a nuclear weapon. They also suggested to reactor theorists that the interaction fast effect might make an important contribution to a controlled slow-neutron chain reaction using natural water as moderator/coolant. (In the capable hands of others, this perception of the theorists led eventually to most of the civilian and naval power reactors.) Items of personal research are briefly mentioned, viz., observation of the radioactive decay of the free neutron, of nuclear recoil due to neutrino emission, and of the atomic consequences of radioactive decay. The periods covered are 1940–1944 with the Cyclotron Group at the Metallurgical Laboratory, Chicago, and 1944–1968 at Oak Ridge, Tennessee.