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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
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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
Westinghouse’s lunar microreactor concept gets a contract for continued R&D
Westinghouse Electric Company announced last week that NASA and the Department of Energy have awarded the company a contract to continue developing a lunar microreactor concept for the Fission Surface Power (FSP) project.
Jeffrey A. Favorite
Nuclear Science and Engineering | Volume 175 | Number 1 | September 2013 | Pages 44-69
Technical Paper | doi.org/10.13182/NSE12-17
Articles are hosted by Taylor and Francis Online.
It is often desirable to solve radiation transport problems in one-dimensional spherical geometries even if the actual object being modeled is not spherical. It may be possible to use perturbation theory to account for the difference between the real multidimensional system and the spherical approximation. This idea is tested using uncollided as well as multigroup inhomogeneous transport problems with upscattering. Asymmetric and nonuniform perturbations are made to the shielding (not the source) of spherical geometries, including transformations from a sphere to a cube (the surface transformation function is derived), and Schwinger, Roussopolos, and combined perturbation estimates are applied. For uncollided fluxes, perturbation theory, particularly the Schwinger estimate, worked very well when the response of interest was the flux measured at a symmetric spherical 4 detector external to the geometry, but perturbation theory did not work well when the response of interest was the flux measured at a single external point (unless extra care was taken to account for geometric effects). For neutron-induced gamma-ray line fluxes, the Roussopolos estimate worked well when the response of interest was the flux measured at an external 4 detector or an external point detector.