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The progress so far: An update on the Reactor Pilot Program
It has been about three months since the Department of Energy named 10 companies for its new Reactor Pilot Program, which maps out how the DOE would meet the goal announced by executive order in May of having three reactors achieve criticality by July 4, 2026.
David Bernard, Olivier Fabbris, Romain Gardet
Nuclear Science and Engineering | Volume 179 | Number 3 | March 2015 | Pages 302-312
Technical Paper | doi.org/10.13182/NSE13-104
Articles are hosted by Taylor and Francis Online.
Three similar experiments performed in the 8-MW(thermal) MELUSINE experimental power pool reactor aimed at analyzing 1 GWd/tonne HM spent fuel pellets doped with several actinides and fission products. The goal was to measure the energy-integrated neutron-induced capture cross section in three different neutron spectra (from pressurized water reactor–like to undermoderated ones). This paper summarizes the combined deterministic APOLLO2 and stochastic TRIPOLI4 analysis using the JEFF-3.1.1 European nuclear data library. Very good agreement is observed for most neutron-induced capture cross sections of actinides except for a clear underestimation of 241Am(n,γ). An accurate value of its associated isomeric branching ratio is also suggested. A resonant fluctuation (factor of 2.7 between the two available excited levels regarding the l = 0 total orbital momenta) is suggested for this isomeric branching capture ratio. Finally, a precise value (more accurate than the reported JEFF-3.1.1 one) of the decay branching ratio of 242gAm(β+/ε) is deduced: 0.171 ± 0.001.
