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Nuclear Energy Conference & Expo (NECX)
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.
Yasunori Yamamura
Nuclear Science and Engineering | Volume 58 | Number 3 | November 1975 | Pages 328-331
Technical Note | doi.org/10.13182/NSE75-A26782
Articles are hosted by Taylor and Francis Online.
The macroscopic representation of complicated moderating processes has been investigated to describe the collision integral in the Legendre polynomial expansion of the neutron transport equation in terms of the macroscopic moderating parameter, defined as the ratio of the l'th-order Legendre component of the slowing-down density to the corresponding collision integral. This approach is similar in form to the Wigner-type continuous slowing-down theory, but the present moderating parameter is a function of lethargy, space, and time. For practical applications a new Greuling-Goertzel approximation is proposed based on the factorization of the angular flux. The present parameter, γl(u), is defined so as to compensate the difference between the lethargy spectrum of the space- and time-independent flux and the exact spectrum.