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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
J. K. Fletcher
Nuclear Science and Engineering | Volume 84 | Number 1 | May 1983 | Pages 33-46
Technical Paper | doi.org/10.13182/NSE83-A17455
Articles are hosted by Taylor and Francis Online.
A solution of the multigroup neutron transport equation in one, two, or three space dimensions is presented. The flux φg(r, Ω) at point r in direction for energy group g takes the form of an expansion in unnormalized spherical harmonics. Thus, where θ and φ are the axial and azimuthal angles of Ω, the associated Legendre polynomials, and N an arbitrary odd number. Using the various recurrence formulas for , a linked set of first-order differential equations in the moments results. Terms with odd 1 are eliminated yielding a second-order system to be solved by two methods. First, a finite difference formulation using an iterative procedure is given, and second, in XYZ and XY geometry, a finite element solution is presented. Results for a test problem using both methods are exhibited and compared.