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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
Standards Program
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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Oct 2025
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Nuclear Science and Engineering
December 2025
Nuclear Technology
November 2025
Fusion Science and Technology
Latest News
Illinois legislature lifts ban on nuclear energy, funds clean energy
The Illinois General Assembly passed a clean energy bill on October 30 that would, in part, lift a 30-year moratorium on new nuclear energy in the state and create incentives for more energy storage.
Nuclear Criticality Safety Division 2025 Conference
Japan Atomic Energy Agency (JAEA)
Group Leader in the Criticality Safety Research Group of the Nuclear Safety Research Center
Dr. Satoshi Gunji completed his PhD in Engineering at Tohoku University before joining the Power and Industrial Systems Research and Development Center of Toshiba Corporation in 2007 as a researcher in the Nuclear Reactor System Analysis Group. Before the accident at the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant, his main work was on criticality safety of next-generation light water reactor fuel. He was also an experimenter and an operator of the Toshiba Nuclear Critical Assembly.
After Toshiba decided to decommission the NCA, he moved to the Criticality Safety Research Group at the Japan Atomic Energy Agency (JAEA), where he currently works. At the time, JAEA was proceeding with plans to modify the criticality assembly STACY to conduct criticality assessments of the fuel debris generated by the FDNPP accident. He participated in this project as a criticality safety expert and planned the criticality experiment plans. STACY achieved first criticality in 2024, and he has been directing subsequent experiments.
Last modified August 26, 2025, 10:54am CDT
