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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
A. dos Santos, R. Fuga, R. Jerez, A. Y. Abe, E. A. Filho
Nuclear Science and Engineering | Volume 137 | Number 1 | January 2001 | Pages 52-69
Technical Paper | doi.org/10.13182/NSE01-A2175
Articles are hosted by Taylor and Francis Online.
Two experiments performed at the IPEN/MB-01 reactor are suggested to serve as a benchmark problem to verify mainly the adequacy of the 235U nuclear data for criticality analyses and for the isothermal reactivity coefficient determination of thermal reactors. The experiments are claimed to be well-defined, and they are suitable for a benchmark problem partially due to their small uncertainties and partially due to the lack of any sort of calculated correction factors or any quantity that comes either from the calculational methodologies or from another experiment. The isothermal experiment fulfills a specific need to introduce a reactor response that is sensitive to the 235U cross-section shape below 5 meV. This feature could be accomplished due mainly to the very precise control bank system characteristics of the IPEN/MB-01 reactor. The MCNP-4B calculational analyses reveal that the most recent 235U evaluation (Leal-Derrien-Larson's evaluation) incorporated in ENDF/B-VI release 5 performs well in the theory-experiment result comparisons of the aforementioned experiments. Particularly in the isothermal experiment, ENDF/B-VI release 5 produces results that even considering the deviations inherent to the Monte Carlo method meet the desired accuracy (±1.0 pcm/°C) for the isothermal reactivity coefficient determination in contrast to the JEF-2.2 and JENDL-3.2 libraries, which produce unacceptably high keff results. The main reasons are the 235U nuclear data in the case of JEF-2.2 and the nuclear data of both 235U and iron in the case of JENDL-3.2.