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Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Rodolfo M. Ferrer, Joshua M. Hykes
Nuclear Science and Engineering | Volume 197 | Number 2 | February 2023 | Pages 333-350
Technical Paper | doi.org/10.1080/00295639.2022.2053491
Articles are hosted by Taylor and Francis Online.
The Spatially Dependent Self-Shielding (SDSS) method has been implemented into CASMO5 within the framework of Equivalence Theory. The Optimal Two-Term Rational (OTTR) approximation is extended in the SDSS method to the Stoker-Weiss treatment of concentric annular fuel subdivisions. Reference fuel-to-fuel probabilities are required by the OTTR and obtained by performing a series of fixed-source, two-dimensional transport calculations for individual pin cell types using the method of characteristics. Several algorithms used in searching for the OTTR coefficients are evaluated with the goal of obtaining the best practical accuracy at minimal computational cost. Numerical results are presented that provide a comparison of various choices of search algorithms and show improved accuracy obtained by increasing the degrees of freedom in the rational approximation. Spatial profiles of the 238U microscopic absorption cross sections in the resonance range obtained using the Distributed Resonance Integral (DRI) and SDSS methods are compared to reference results from Monte Carlo calculations. The comparison highlights the inherent advantages of SDSS over the previous DRI method.