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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
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.
B. D. Ganapol, D. E. Kornreich, J. A. Dahl, D. W. Nigg, S. N. Jahshan, C. A. Wemple
Nuclear Science and Engineering | Volume 118 | Number 1 | September 1994 | Pages 38-53
Technical Paper | doi.org/10.13182/NSE94-A19020
Articles are hosted by Taylor and Francis Online.
The solution to the searchlight problem for monoenergetic neutrons in a semi-infinite medium with isotropic scattering illuminated at the free surface is obtained through the numerical evaluation of an analytical expression for the scalar flux at various positions within the medium. The sources considered are normally incident pencil beam and isotropic point sources as well as a longitudinal uniformly distributed source. The analytic solution is effected by a recently developed numerical inversion technique applied to the Fourier-Bessel transform. The transform inversion results from the solution method of Rybicki, where the two-dimensional problem is solved by casting it as a variant of a one-dimensional problem. The numerical inversion results in a highly accurate solution. Comparisons of the analytic solution with results from Monte Carlo (MCNP) and discrete ordinates transport codes (DORT, TWODANT, and SMARTEPANTS) show excellent agreement. These comparisons, which are free from any associated data or cross-section set dependencies, provide significant evidence of the proper operation of the transport codes tested.