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Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Jan 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
January 2026
Nuclear Technology
December 2025
Fusion Science and Technology
November 2025
Latest News
From Capitol Hill: Nuclear is back, critical for America’s energy future
The U.S. House Energy and Commerce Subcommittee on Energy convened its first hearing of the year, “American Energy Dominance: Dawn of the New Nuclear Era,” on January 7, where lawmakers and industry leaders discussed how nuclear energy can help meet surging electricity demand driven by artificial intelligence, data centers, advanced manufacturing, and national security needs.
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
