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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Nuclear Dirigo
On April 22, 1959, Rear Admiral George J. King, superintendent of the Maine Maritime Academy, announced that following the completion of the 1960 training cruise, cadets would begin the study of nuclear engineering. Courses at that time included radiation physics, reactor control and instrumentation, reactor theory and engineering, thermodynamics, shielding, core design, reactor maintenance, and nuclear aspects.
Adimir dos Santos, Ricardo Diniz
Nuclear Science and Engineering | Volume 178 | Number 4 | December 2014 | Pages 459-478
Technical Paper | doi.org/10.13182/NSE14-10
Articles are hosted by Taylor and Francis Online.
The evaluation of the experiments of the effective delayed neutron parameters and reactivity performed in the IPEN/MB-01 research reactor facility has been successfully accomplished. The evaluated data are of very good quality and fulfill the requirements of a benchmark. The recently released MCNP6 together with the ENDF/B-VII.1, JENDL-4.0, JEFF-3.1.1, ENDF/B-VII.0, and JENDL-3.3 nuclear data libraries has been employed to calculate the effective delayed neutron parameters adopting the benchmark model of the IPEN/MB-01 reactor available in the International Handbook of Reactor Physics Benchmark Experiments. The analysis reveals that all these nuclear data libraries produced satisfactory results for βeff, βeff/Λ, and Λ. The same cannot be said for determining the reactivity using the Inhour equation. It was shown that there is a clear tendency to increase the deviation with the absolute value of the reactivity for negative periods. Only JENDL-3.3 and JEFF-3.1.1 produced results that are inside the 3σ range of the benchmark value uncertainty. Specifically for the case of ENDF/B-VII.1, a good part of this discrepancy is due to the decay constant of the first group of delayed neutrons, which is overestimated according to the experimental value measured in the IPEN/MB-01 reactor.
