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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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.
Koji Oishi, Yujiro Ikeda, Hiroshi Maekawa, Tomoo Nakamura
Nuclear Science and Engineering | Volume 103 | Number 1 | September 1989 | Pages 46-58
Technical Paper | doi.org/10.13182/NSE89-A23659
Articles are hosted by Taylor and Francis Online.
The neutron spectra in a concrete assembly bombarded by 14-MeV neutrons are measured by a miniature NE-213 spectrometer and the multifoil activation method. The results obtained are within experimental error. The measured spectra are compared with calculated results obtained using the two-dimensional DOT3.5 transport code with 125-group structure cross-section libraries based on ENDF/B—IV, JENDL-2, and JENDL-3T (the test version of JENDL-3). In the deuterium-tritium neutron peak region, the measured and calculated neutron spectra are in agreement. However, all the calculations overestimate the measurements by 10 to 50% in the mega-electron-volt region. In a still lower neutron energy range, where the 197Au(n,γ)198Au reaction is dominant, discrepancies from −30 to +40% are observed. Possible reasons are considered, but none explain the discrepancies. Further investigation of the secondary neutrons in the mega-electron-volt region emitted by elastic and inelastic scattering from the main components of concrete, such as oxygen, silicon, and calcium, is necessary to improve the agreement between experimental and calculated results.