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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.
W. P. Poenitz
Nuclear Science and Engineering | Volume 40 | Number 3 | June 1970 | Pages 383-388
Technical Paper | doi.org/10.13182/NSE70-A20189
Articles are hosted by Taylor and Francis Online.
The ratios σγ(238U)/σ/(235U), σγ(238U)/σγ(239Pu), and σf (239Pu)/σf (235U) have been measured in the energy range 130 to 1400 keV. The activation technique was used to determine the capture rate in 238U. The 278 keV γ ray emitted in the decay of 239Np was detected by means of a Ge(Li) detector. The counting efficiencies have been absolutely determined for the measurement of σγ(238U)/σf(239Pu). For the determination of the ratio σγ(238U)/σf(235U) the counting efficiencies have been eliminated by a measurement of the ratio at thermal-neutron energies. The ratio σf(239Pu)/σf(235U) has been measured in a back-to-back gas scintillation counter using the time-of-flight method for background suppression. The measurements resulted in an overdetermination of two unknown quantities by three measured values. The fitted values derived from the collective results were in good agreement with the individual measured ratios.
