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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.
Jesson Hutchinson, Jennifer Alwin, Alexander McSpaden, William Myers, Michael Rising, Rene Sanchez
Nuclear Technology | Volume 207 | Number 1 | December 2021 | Pages S62-S80
Technical Paper | doi.org/10.1080/00295450.2021.1908076
Articles are hosted by Taylor and Francis Online.
Criticality experiments with 235U (metal and hydride) and 239Pu (metal) were performed during the Manhattan Project. Results from these experiments provided necessary information for the success of the Manhattan Project [LA-1033 to LA-1036 (1947), LA-02532-MS V I (1961), and Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945 (1993)]. These experiments have been previously described in compilations made after the Manhattan Project, but those works are either lacking in technical details or are not publicly available. This work aims to provide detailed information while showcasing the enduring impact of these experiments 75 years after they were performed. Furthermore, we use modern computational methods embodied in the MCNP6® code and ENDF data to analyze and interpret these historic measurements. The world’s first four criticality accidents are also discussed, as lessons learned from these helped shape the field of criticality experiments.