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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.
Albert E. Evans, M. S. Krick
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 652-659
Technical Paper | doi.org/10.13182/NSE77-A15208
Articles are hosted by Taylor and Francis Online.
A 3He neutron spectrometer has been used to measure the energy spectra of delayed neutrons in equilibrium with fission induced by sub-MeV neutrons incident upon 235U, 238U, and 239Pu. Full contribution of shorter lived delayed neutron groups not previously measured was ensured by bombarding samples for 35 out of every 100 ms and measuring delayed neutrons for 40 ms between each bombarding pulse. Results show delayed neutron spectra of somewhat higher average energy than have previously been reported. Examination of the energy end points of delayed neutron emitters as a function of precursor half-life shows that the higher average delayed neutron energies are probably due to the inclusion of neutrons from the shorter lived precursors.