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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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.
Luisa F. Hansen, Calvin Wong, Ted T. Komoto, Bertram A. Pohl, Eugene Goldberg, Robert J. Howerton, Walter M. Webster
Nuclear Science and Engineering | Volume 72 | Number 1 | October 1979 | Pages 35-51
Technical Paper | doi.org/10.13182/NSE79-A19307
Articles are hosted by Taylor and Francis Online.
The neutron and gamma-ray leakage spectra from pulsed spheres having a radius equal to 1.0 mean-free-path (mfp) for 14-MeV neutrons in 232Th, 235U (with radii of 0.7 and 1.5 mfp), 228U (with radii of 0.8 and 2.8 mfp), and 239Pu (with radii of 0.7 and 1.25 mfp) were measured by using time-of-flight techniques. The neutron spectra were measured between 0.9 and 15 MeV using stilbene and NE-213 scintillators. For the gamma rays, the electron recoil spectra were measured between 0.35 and 8 MeV with the NE-213 detector only. Pulse-shape discrimination and flight paths of ∼10 m were used in these measurements. The measured spectra are compared with calculations carried out with TARTNP, a coupled neutron-photon Monte Carlo transport code. The Lawrence Livermore Laboratory ENDL (neutron and photon cross sections) and ENDF/B-IV libraries were used in these calculations. In the region between 10 and 15 MeV, the calculated neutron spectra are in good agreement with the measurements (±5%). The maximum discrepancy observed for the neutrons between 0.9 and 10 MeV is 30%. The notable exception is 232Th, where calculations carried out with the ENDF/B-IV underestimate by a factor of 2 the neutron emission between 5 and 10 MeV. The gamma-ray emission calculations were carried out only with ENDL because of its overall better representation of the neutron measurements; ENDL overestimates the gamma-ray production, with discrepancies ranging between 5 and 20%. However, use of the measured detector efficiency would reduce the maximum discrepancy to <13%. To facilitate the use of the neutron data for calculational purposes by other laboratories, an “experimental” one-dimensional neutron energy spectrum is given for each measurement.