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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.
J. V. Walker
Nuclear Science and Engineering | Volume 22 | Number 1 | May 1965 | Pages 94-101
Technical Paper | doi.org/10.13182/NSE65-A19766
Articles are hosted by Taylor and Francis Online.
The effects of neutron flux anisotropy upon thermal-neutron flux perturbations were found by experimentally determining the perturbations induced by foils placed in fluxes of known nonuniformities. Anisotropies in the magnitude of the vector flux were introduced by placing a ‘black’ cadmium absorber sheet in an isotropic flux produced by a uniform slowing-down source in water. The resulting angular and spatial distributions of the thermal-neutron flux were computed by using Yvon's method to solve the Boltzmann equation for an absorbing half space containing a uniform slowing-down source. Using indium foils with thicknesses from 14 mg/cm2 to 184.9 mg/cm2, the relative flux perturbations were measured to within ±1% in regions which varied from a highly directional flux at the cadmium surface to essentially an isotropic distribution several mean free paths from the absorber. The experimental data indicated that the flux perturbations remained constant at all distances greater than about three mean free paths from the non-reentrant boundary, but that the flux depression decreased in the region near and vanished at the boundary. It was concluded, contrary to earlier predictions, that flux perturbation theories, based upon isotropic flux models, cannot be used to correct flux perturbations induced in all anisotropic fluxes. It was pointed out that, if this effect is overlooked, significant errors may exist in some relative or absolute flux measurements made in the region near a boundary or absorber.