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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
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.