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May 31–June 3, 2026
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Perpetual Atomics, QSA Global produce Am fuel for nuclear space power
U.K.-based Perpetual Atomics and U.S.-based QSA Global claim to have achieved a major step forward in processing americium dioxide to fuel radioisotope power systems used in space missions. Using an industrially scalable process, the companies said they have turned americium into stable, large-scale ceramic pellets that can be directly integrated into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
Hans Ludewig
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 18-26
Technical Paper | doi.org/10.13182/NSE71-A18901
Articles are hosted by Taylor and Francis Online.
An analysis of five metal critical assemblies constructed at the Los Alamos Scientific Laboratory is described in this paper. Nuclear data based on ENDF/B Versions 1 and 2 and the DSN method are used in the analysis. Special attention is focused on the variation of α (the ratio of capture-to-fission cross sections) for 239Pu. A study of the sensitivity of keff to the number of angular quadratures and the scattering model used in the calculation is also investigated. Finally, in addition to determining the reactivity of each core, the spatial variation of a spectral index for two cores is investigated.
