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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).
L. W. Weston, J. H. Todd
Nuclear Science and Engineering | Volume 79 | Number 2 | October 1981 | Pages 184-196
Technical Paper | doi.org/10.13182/NSE81-A27407
Articles are hosted by Taylor and Francis Online.
The neutron capture cross section of 237Np was measured from 0.01 eV to 200 keV. The capture cross section was normalized at 0.0253 eV to a value of 180 ± 6 b derived from previous total cross-section measurements in the resonance region of neutron energies and the shape of the present data from 0.0253 eV to the resonance region. Resonance parameters were derived for the neutron energy region from 0.01 to 100 eV. Agreement with ENDF/B-V is poor in the thermal region (6.4%), excellent in the resonance region (∼2%) except for the 0.491-eV resonance, and good (∼5%) in the keV neutron energy region. An uncertainty analysis including a correlation matrix for group-averaged cross sections is presented. These results are important both for thermal and fast reactor applications and the calculation of 238Pu production, an intense alpha emitter.
