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2026 Annual Conference
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).
Donald Bogart, Donald F. Shook, Daniel Fieno
Nuclear Science and Engineering | Volume 53 | Number 3 | March 1974 | Pages 285-303
Technical Paper | doi.org/10.13182/NSE74-A23354
Articles are hosted by Taylor and Francis Online.
Integral tests of evaluated ENDF/B high-energy cross sections have been made by comparing measured and calculated neutron leakage flux spectra from spheres of various materials. An Am-Be(α,n) source was used to provide fast neutrons at the center of the test spheres of beryllium, polyethylene, lead, niobium, molybdenum, tantalum, and tungsten. The absolute leakage flux spectra were measured in the energy range from 0.5 to 12 MeV using a calibrated NE-213 liquid scintillator neutron spectrometer. Absolute calculations of the spectra were made using Version-Ill ENDF/B cross sections and an Sn discrete-ordinates multigroup transport code., Generally excellent agreement was obtained for beryllium, polyethylene, lead, and molybdenum, and good agreement was observed for niobium although discrepancies were observed for some energy ranges. The poor comparative results obtained for tantalum and tungsten are attributed to unsatisfactory nonelastic cross sections. The experimental sphere leakage flux spectra are tabulated and serve as possible benchmarks for these elements against which reevaluated cross sections may be tested.