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May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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).
P. L. Reeder, R. A. Warner
Nuclear Science and Engineering | Volume 79 | Number 1 | September 1981 | Pages 56-64
Technical Paper | doi.org/10.13182/NSE81-A19042
Articles are hosted by Taylor and Francis Online.
Average energies of the delayed neutron spectra from 34 precursors have been compiled from the literature to give a set of best values. Average energies of six-group and equilibrium spectra are calculated by summing weighted values of the individual precursors. These calculated average energies are in reasonable agreement with the rather limited experimental data. Equilibrium delayed neutron spectra are calculated by summing spectra for individual precursors. The calculated equilibrium spectra are then compared to an approximate spectrum based on a Maxwellian distribution with just one parameter, the average energy. Sets of experimental spectra for individual precursors measured at two different laboratories are compared. The Maxwellian shape gives reasonable agreement with one set. The other set has more neutrons at low energy and does not fit a Maxwellian shape.
