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Front-end nuclear fuel supply cooperation: Turning allied interdependence into strategic advantage
The global nuclear revival, which is fueled by unprecedented demand for firm, affordable, dispatchable power for artificial intelligence and data center build-out, energy security imperatives, and climate commitments, has exposed a structural reality of the Western fuel cycle: No single allied nation currently possesses the full suite of front-end capabilities. From mining through conversion, enrichment, fabrication, and the emerging deconversion and metallization steps required for reactor fuels, capability is distributed across Canada, France, Japan, the United Kingdom, and the United States (collectively, the “Sapporo Five”), as well as a small group of close partners.
C. E. Ragan III, G. F. Auchampaugh, A. Hemmendinger, M. G. Silbert
Nuclear Science and Engineering | Volume 61 | Number 1 | September 1976 | Pages 33-39
Technical Paper | doi.org/10.13182/NSE76-A28458
Articles are hosted by Taylor and Francis Online.
A benchmark measurement of the neutron leakage spectrum from a pulsed 38-kg uranium (93.5% 235U) sphere has been made using time-of-flight techniques. The sphere had a multiplication of ∼11 for 14-MeV neutrons, and a neutron hold-up time of ∼40 nsec. The centrally located source of 14.1 ± 0.8-MeV neutrons, produced by bombarding a tritium gas target with pulses of low-energy deuterons, was isotropic to ±7.7%. Neutrons in the 0.180- to 16.0-MeV energy range were detected at the end of a 39-m flight path by an Ne-213 liquid scintillator employing pulse-shape discrimination. The detector efficiency was measured over this same energy range using monoenergetic neutrons from the T(p,n) T(d,n), and D(d,n) reactions. The measured neutron flux as a function of energy is compared with the results of Monte Carlo calculations performed with the MCN code. Uranium cross sections from ENDF/B-IV and an older set from Lawrence Livermore Laboratory were used in these calculations. The results calculated using the ENDF/B-IV cross sections are in good agreement with the measurements, especially in the 1- to 6-MeV energy region where the uncertainties in both the calculated and experimental results are the smallest.