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UIUC submits MMR construction permit application
The University of Illinois–Urbana-Champaign, in partnership with Nano Nuclear Energy, has submitted a construction permit application to the Nuclear Regulatory Commission for construction of a Kronos micro modular reactor (MMR). This is the first major step in the two-part 10 CFR Part 50 licensing process for the research and test reactor and is the culmination of years of technical refinement and regulatory alignment.
The team chose to engage with the NRC in a preapplication readiness assessment, providing the agency with draft versions of the majority of the CPA’s technical content for feedback, which is expected to ensure a high-quality application.
R. N. Hwang
Nuclear Science and Engineering | Volume 167 | Number 1 | January 2011 | Pages 1-39
Technical Paper | doi.org/10.13182/NSE10-004
Articles are hosted by Taylor and Francis Online.
The fundamental basis regarding treatment of unresolved resonances and the construction of probability tables and the relevant issues with their application to reactor physics is critically examined. A theoretical model using integral transform techniques is developed that provides a viable alternative to the stochastic-based “ladder” method widely used to construct probability tables. A brief review of the statistical theory for treating the unresolved resonances is presented, followed by a critical examination of these methods. Then a reference method for computing various probability distributions at 0 K is derived analytically for Breit-Wigner resonances. This reference model provides the analytical insight and conceptual basis for extension to the general case of arbitrary temperature. The generalization to arbitrary temperature is accomplished using the Chebyshev expansion while maintaining the general forms of the distributions. Results of extensive benchmark calculations to verify the viability of the proposed method are presented. Finally, there is discussion of the remaining challenges in application of this new analytical approach, in particular, the issue of its extension beyond the Breit-Wigner approximation.