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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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.
K. Takeuchi, S. Tanaka, M. Kinno
Nuclear Science and Engineering | Volume 78 | Number 3 | July 1981 | Pages 273-283
Technical Paper | doi.org/10.13182/NSE81-A20304
Articles are hosted by Taylor and Francis Online.
For the transport calculation of gamma rays including bremsstrahlung, an improvement is made in the PALLAS-PL, SP discrete ordinates direct-integration code to enable evaluation of bremsstrahlung. The electrons resulting from Compton scattering, pair production, and the photoelectric effect are individually evaluated based on the primary gamma-ray flux calculated with the code. Bremsstrahlung production is then calculated by applying the continuous electron slowing down model. For this purpose, both the electron stopping power and the differential cross section for bremsstrahlung production are evaluated. Comparisons of PALLAS calculations with experiments are presented to test the validity of this code and method. As a result, it has been observed that the PALLAS calculations result in fairly good agreement with experiments, except for some discrepancies at energies below ∼0.7 MeV in the energy spectrum transmitted through lead and iron from a plane isotropic 6.2-MeV gamma-ray source. There is agreement also with another experiment on the attenuation by lead of transmission dose ∼8-MeV gamma rays in a normally incident from a plane monodirectional source. Further, there is agreement with the energy spectrum in lead calculated by a moments method for a plane monodirectional 8-MeV source without inclusion of secondary photons. Also presented are calculations of buildup factors and of energy spectra, including the contribution of bremsstrahlung, for a plane monodirectional beam of 8-MeV gamma rays normally incident on lead and on tungsten.