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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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.
L. C. Leal, G. de Saussure, R. B. Perez
Nuclear Science and Engineering | Volume 109 | Number 1 | September 1991 | Pages 1-17
Technical Paper | doi.org/10.13182/NSE91-A23840
Articles are hosted by Taylor and Francis Online.
A detailed evaluation of the R matrix resonance parameters describing the interaction of neutrons with 235U has been performed up to 500 eV using the most recent high-resolution measurements of the 235U neutron cross sections. The availability of 235U spin-separated neutron cross-section data, in conjunction with the use of the Δ3 statistics of Metha and Dyson, has made possible a detailed study of the statistical distribution of the resonance parameters and their average values. The present R matrix resonance parameters have been converted into equivalent sets of Adler-Adler parameters and multipole momentum space expansion parameters. Extensive validation of this evaluation has been performed by comparing self-shielded fission rates computed with these R matrix parameters with the measurements of Czirr; a test of the ENDF/B unresolved resonance formalism for the calculation of 235U self-shielding factors is also presented.
