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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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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.
Carl Klahr
Nuclear Science and Engineering | Volume 1 | Number 4 | August 1956 | Pages 253-267
Technical Paper | doi.org/10.13182/NSE56-A18601
Articles are hosted by Taylor and Francis Online.
Multigroup calculations of neutron flux and current in the reflector of a thermal reactor may be seriously in error at intermediate neutron energies. This is a consequence of the assumed linear flux variation with lethargy within each group that is implicit in the multigroup method. As a result, most multi-group treatments show marked deviations from age theory at distances of several slowing down lengths (or more) from the source region. Calculations have been made to show the variation of the error in a particular multigroup treatment as a function of distance from the source (measured in slowing down lengths) and of the number of groups.
