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DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. That's the same amount of HALEU—900 kg—that the company today announced it has delivered to the DOE, completing Phase II of its contract. According to Centrus, the contract extension, which allows the company to begin Phase III, is valued at about $110 million through June 30, 2026.
J. T. Mihalczo
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 393-414
Technical Paper | doi.org/10.13182/NSE74-5
Articles are hosted by Taylor and Francis Online.
Cross-correlation measurements between the pulses from an ionization counter containing a 252Cf neutron source, which provided the initiators of fission chains in a neutron-multiplying assembly, and the pulses from a detector observing the particles from the fission chains leaking from the assembly were performed for unmoderated and polyethylene-moderated uranium (∼93 wt% 235U)-metal cylindrical assemblies with uranium masses varying from 12 to 160 kg and with prompt-neu-tron decay constants varying from 3 × 103 to 108 sec-1. The applicability of this randomly pulsed neutron method with 252Cf as the neutron source for the determination of the prompt-neutron decay in plutonium was investigated in experiments with unmoderated plutonium-metal assemblies with masses varying from 2.2 to 16 kg and with spontaneous fission rates from 240Pu varying from 4.5 × 104 to 8.2 × 105 fiss/sec. These assemblies included spheres and parts of spheres of plutonium with 4.5 or 20.1 at.% 240Pu. The ratio of the correlated count rate in the randomly pulsed neutron method to that in a Rossi-α method is inversely proportional to the detector efficiency and was as large as 8000 for some assemblies where both measurements were made. Thus, the randomly pulsed neutron method allowed the determination of the prompt-neutron decay without the use of a complicated pulsed-neutron source where the Rossi-α method was not practical. In assemblies for which Rossi-α measurements were also made, the prompt-neutron decay constant agreed within the precision (<1%) of the measurements with those obtained in much less time by this technique. Since the prompt-neutron decay can also be determined for plutonium-metal assemblies with ∼20 at.% 240Pu, using a californium source as small as 3000 fiss/sec, this technique can be used for the subcriticality determination for both unreflected and unmoderated uranium (93.2)- or plutonium-metal assemblies.
