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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Fusion Science and Technology
October 2025
Latest News
DOE’s latest fusion energy road map aims to bridge known gaps
The Department of Energy introduced a Fusion Science & Technology (S&T) Roadmap on October 16 as a national “Build–Innovate–Grow” strategy to develop and commercialize fusion energy by the mid-2030s by aligning public investment and private innovation. Hailed by Darío Gil, the DOE’s new undersecretary for science, as bringing “unprecedented coordination across America's fusion enterprise” and advancing President Trump’s January 2025 executive order, on “Unleashing American Energy,” the road map echoes plans issued by the DOE’s Office of Fusion Energy Sciences (FES) in 2023 and 2024, with a new emphasis on the convergence of AI and fusion.
The road map release coincided with other fusion energy events held this week in Washington, D.C., and beyond.
Y. Harima, Y. Sakamoto, S. Tanaka, M. Kawai
Nuclear Science and Engineering | Volume 94 | Number 1 | September 1986 | Pages 24-35
Technical Paper | doi.org/10.13182/NSE86-A17113
Articles are hosted by Taylor and Francis Online.
A geometric-progression (G-P) method formula, Br = 1 + (B − 1) · (Kx − 1)/(K − 1), accurately represents the buildup factor data as a function of distance for the following reasons: 1. The value of parameter B corresponds to that of the buildup factor at 1 mfp, which is the integration of a basic spectrum for a specified material and for a specified source energy. 2. The variation of parameter K with penetration represents the photon dose multiplication and the change in the shape of the spectrum. Exposure buildup factors for point isotropic sources in an infinite medium approximated by the G-P fitting parameters are in good agreement with the basic data calculated by the PALLAS code, including that of boron for low energies, and of lead, including the effects of bremsstrahlung and fluorescence. The validity of using the G-P parameters to interpolate the buildup factor in μr and in E is ascertained. Furthermore, the extrapolation to the buildup data for depths above 40 mfp is examined.
