ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 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!
Latest Magazine Issues
Oct 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
November 2025
Nuclear Technology
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.
G. C. Baldwin, J. C. Solem
Nuclear Science and Engineering | Volume 72 | Number 3 | December 1979 | Pages 281-289
Technical Paper | doi.org/10.13182/NSE79-A20384
Articles are hosted by Taylor and Francis Online.
We show that upper bounds exist on the density of neutrons that can be moderated to a specified energy from an intense pulsed source of fast neutrons. Expressions are derived for the maximum density in the following cases: (a) a uniform infection of fast neutrons into an infinite moderator, (b) a localized central source in a finite heavy atom moderator, and (c) a point source in an infinite hydrogenous moderator. Correspondingly, upper bounds are given for the rates of single- and multiple-resonance neutron capture.
