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2025 annual assessments out for U.S. reactors
The Nuclear Regulatory Commission has released its 2025 annual performance assessments of the country’s 95 operating commercial nuclear reactors. And of the 95 reactors, all but five earned the highest marks.
Nuclear power plant assessments can fall under one of five categories: Licensee Response, Regulatory Response, Degraded Cornerstone, Degraded Performance, and Unacceptable Performance. Ninety reactors fell under Licensee Response, the highest performance category in safety and security. Plants that achieve this level of performance are subject to a Reactor Oversight Process (ROP) baseline inspection.
Z. F. Kuang, I. Pázsit
Nuclear Science and Engineering | Volume 136 | Number 2 | October 2000 | Pages 305-319
Technical Note | doi.org/10.13182/NSE00-A2161
Articles are hosted by Taylor and Francis Online.
Recently, analytical formulas have been derived for the Feynman- and Rossi-Alpha measurements in accelerator-driven systems. In such systems, due to the multiplicity of the sources, the Feynman- and Rossi-Alpha formulas contain additional terms as compared with the traditional cases. A numerical evaluation of these formulas for systems with such sources is given. An assessment of the contribution of the terms that are novel as compared to the traditional formula is made. These include the terms arising from the source multiplicity, and the prompt-delayed and delayed-delayed correlations. Further, the consequences of averaging the delayed-neutron families are analyzed. Finally, a comparison is made, assuming traditional core material and one possible type of future accelerator-driven system.