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Division Spotlight
Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Omar Chibani
Nuclear Science and Engineering | Volume 137 | Number 2 | February 2001 | Pages 215-225
Technical Paper | doi.org/10.13182/NSE01-A2187
Articles are hosted by Taylor and Francis Online.
A New Monte Carlo code (EBUF) is developed to calculate improved point isotropic photon exposure buildup factors in media. Variance reduction techniques are used to perform calculations up to 60 mean free paths. EBUF accounts for coherent scattering and bound-electron Compton scattering. Bremsstrahlung photons and annihilation gamma rays as well as K and L X-rays are considered. The most recent cross-section data are used. The EBUF exposure buildup factors compare very well with those from the ANS-6.4.3 Working Group (ANS-6.4.3) when the same initial conditions are assumed: no coherent scattering, free-electron Compton scattering, and only K X-ray fluorescence. Next, a detailed physics treatment is used to calculate a representative set of exposure buildup factors in aluminum, iron, lead, water, air, and concrete over a large energy range (20 keV to 10 MeV). The effects of L X-rays are shown for lead at low energy. The EBUF factors are in good agreement with the SN1D code results for low-Z media. Finally, total exposure values from EBUF and ANS-6.4.3 are compared. Quite significant differences are observed because the ANS-6.4.3 calculations do not account for binding effects in Compton scattering, L X-ray fluorescence, and coherent scattering in mixtures.
