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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.
M. J. Barrett
Nuclear Science and Engineering | Volume 14 | Number 2 | October 1962 | Pages 186-191
Technical Paper | doi.org/10.13182/NSE62-A28119
Articles are hosted by Taylor and Francis Online.
The gamma current intensity (flux) and the gamma emission (leakage) of a homogeneous, spherical medium are derived by inserting a source spectrum in the Boltzmann transport equation. In the range of photon energies from 0.5 Mev to 10.5 Mev, Compton scattering by electrons of the medium dominates the energy degradation of photons, so that one may use Klein-Nishina cross sections for the transfer kernel. Lumping the flux into energy groups permits an approximation of the transport equation as a matrix equation. Numerical solutions for the flux and leakage spectra, found by inverting the matrix equation, agree well with the results of previous theoretical studies.
