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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Surplus plutonium for power reactor fuel: What’s on offer
The Department of Energy has a plan for private companies to “dispose of surplus plutonium”—about 19.7 metric tons in both oxide and metal forms—by “making the materials available for advanced nuclear technologies.” A Surplus Plutonium Utilization Program request for applications (RFA) issued October 21 describes the plutonium on offer, and the “thresholds” prospective applicants must meet.
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.