ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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!
Latest Magazine Issues
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
July 2025
Fusion Science and Technology
Latest News
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
E. A. Fischer
Nuclear Science and Engineering | Volume 78 | Number 3 | July 1981 | Pages 227-238
Technical Paper | doi.org/10.13182/NSE81-A20300
Articles are hosted by Taylor and Francis Online.
An approximate method to calculate the parallel neutron leakage in fast reactor slab lattices is described. It is derived from the integral transport equation and assumes isotropic scattering. By using an expansion in terms of oscillating functions, rather than the usual power series expansion in the buckling, it is proven that the method is also valid for voided cells. Results for a two-region cell are presented; they confirm that the widely used Benoist equation is valid for cases when sodium is present. However, for voided or nearly voided cells, the Benoist equation fails, whereas the new method is valid for any cell composition. The same method is applied to find the effective diffusion coefficient for a low-density channel. In the limit of zero buckling, the method reduces to well-known results available in literature by Rowlands. However, the buckling correction, obtained by a consistent expansion of the integral transport equation, is different from similar corrections in the literature.