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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
K. F. Hansen, B. V. Koen, W. W. Little, Jr.,
Nuclear Science and Engineering | Volume 22 | Number 1 | May 1965 | Pages 51-59
Technical Paper | doi.org/10.13182/NSE65-A19762
Articles are hosted by Taylor and Francis Online.
A numerical procedure for the integration of the reactor kinetics equation is developed. It has the property of being numerically unconditionally stable for all values of the reactivity or integration-step size. The basic assumption of the method is that the neutron and precursor densities behave exponentially with a frequency characteristic of the asymptotic frequency corresponding to the reactivity. As a consequence of the assumption, and the factoring of the kinetics equation, it is then shown that for constant reactivity the asymptotic numerical eigensolution is exactly the asymptotic eigensolution of the differential kinetics equations. Thus, for constant reactivity, the asymptotic numerical solution can be shown to differ from the asymptotic analytic solution by at most a constant factor, proportional to ht2, for all time.
