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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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
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.
J. K. Fletcher
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 249-255
Technical Note | doi.org/10.13182/NSE80-A19455
Articles are hosted by Taylor and Francis Online.
The transport equation is considered in toroidal geometry using an expansion of Ψ(r, Ω) in unnormalized spherical harmonics, i.e., with being associated Legendre polynomials. The variable r is the position vector and Ω the direction with axial and azimuthal angles θ and , respectively. Equations for ψlm(r) and γlm(r) are obtained and a method of solution that has worked in other geometries is outlined.