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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
J. K. Fletcher
Nuclear Science and Engineering | Volume 77 | Number 3 | March 1981 | Pages 367-372
Technical Note | doi.org/10.13182/NSE81-A19846
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The source-free monoenergetic transport equation can be written as where for plane and for spherical geometries, respectively; Ω is the direction of motion with θ as its angle to the axis, An analytic expression for ψ(Z, cosθ) of the form is considered where Pn(cosθ) is the Legendre polynomial of order n; are combinations of exponential functions for the plane case and Bessel functions in the spherical formulation. A simple algorithm is developed that enables solutions to be found for any N using a small computer program.