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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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.
Ashok Kumar, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 67 | Number 1 | July 1978 | Pages 120-129
Technical Note | doi.org/10.13182/NSE78-A27242
Articles are hosted by Taylor and Francis Online.
Using multigroup diffusion theory with energy-dependent boundary conditions, the propagation of thermal-neutron waves has been studied in finite assemblies of beryllium and beryllium oxide. At different frequencies, we have calculated α and ξ for the discrete (or pseudo-discrete) mode as well as effective values of α(z) and ξ(z) (which include the effect of the source and higher modes) at a distance, z, from the source plane. In the case of beryllium, the results are in agreement with experimental findings of Miles et al. As observed by Miles et al., we find oscillations in the calculated values of α(z) and ξ(z) in a certain distance range beyond a certain frequency, which decreases with the decrease of transverse size of the assembly. Furthermore, in conformity with the experimental results of Miles et al., we find that with a decrease in the transverse dimensions of the assembly, the oscillations become larger, until one goes to very small assemblies, where these oscillations tend to smooth out. In the case of beryllium oxide, since no agreed value of Debye temperature exists and since the energy distribution of source neutrons is not known, only a qualitative comparison with the experimental results of Ritchie and Whittlestone has been possible.