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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.
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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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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.
E. M. Kinderman, H. W. Lefevre, H. H. Van Tuyl
Nuclear Science and Engineering | Volume 5 | Number 4 | April 1959 | Pages 264-268
Technical Paper | doi.org/10.13182/NSE59-A25595
Articles are hosted by Taylor and Francis Online.
An activation method was used to measure the neutron capture cross sections of Np239. Two isomers of Np240 have been reported: a 7-min daughter of U240 and a 1-hr isomer produced by alpha bombardment of U238. Examination with a gamma scintillation spectrometer of the activity produced by neutron activation of Np239 gave positive evidence for the 7-min isomer as a product of neutron capture in Np239. The 1-hr isomer is also produced, although the evidence for it was complicated by fission product activity. Genetic linkage between the isomers was not detected and is less than 5 per cent. The measured cross sections for pile neutrons are 31 ± 6 barns and barns for the 7-min and 1-hr isomers. These values are based upon a 2.8 per cent abundance of the 1.5-Mev gamma of the 7-min isomer and a 38 per cent abundance for the 0.97-Mev gamma, of the 1-hr isomer. These results are relative to a gold thermal cross section of 99 barns.