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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Thomas M. Sutton
Nuclear Science and Engineering | Volume 197 | Number 2 | February 2023 | Pages 164-175
Technical Paper | doi.org/10.1080/00295639.2022.2065872
Articles are hosted by Taylor and Francis Online.
The results of neutron Monte Carlo (MC) transport calculations are subject to random fluctuations about their expected values. The term “neutron clustering” refers to situations in which these fluctuations exhibit particularly strong spatial correlations in iterated-fission-source calculations. Various idealized models of the MC process have been developed to study this phenomenon. Over time, these models have evolved to more realistically reflect the algorithms used in MC codes. This paper continues along this path by including the possibility that some neutrons will not terminate in an event that can potentially produce new neutrons and by considering an algorithm without replacement (WOR) for selecting the neutron source sites. It is shown that sampling source sites WOR versus with replacement can greatly reduce the degree of clustering.