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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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.
D. Graham Foster, Jr.
Nuclear Science and Engineering | Volume 8 | Number 2 | August 1960 | Pages 148-156
Technical Paper | doi.org/10.13182/NSE60-A25790
Articles are hosted by Taylor and Francis Online.
The age to indium resonance of nearly monoenergetic 0.97-Mev neutrons from spherical Na-γ-Be sources has been measured in water and kerosene. The age from a point source is inferred by extrapolation from measurements made with sources ¾ and ⅜ in. in diameter. The flux age is 13.9 ± 0.2 cm2 in water and 13.8 ± 0.2 cm2 in kerosene. Calculations by the moments method give 13.9 ± 0.1 cm2 in each medium, in excellent agreement with the measurements. The thermal migration area measured concurrently is 21.5 ± 0.4 cm2 in water and 20.6 ± 0.4 cm2 in kerosene. The migration area calculated from the resonance age is 22.2 ± 0.5 cm2 in water and 21.8 ± 0.5 cm2 in kerosene. Both of these are substantially larger than the measured values.
