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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
Senate committee hears from energy secretary nominee Chris Wright
Wright
Chris Wright, president-elect Trump’s pick to lead the U.S. Department of Energy, spent hours today fielding questions from members of the U.S. Senate’s committee on Energy and Natural Resources.
During the hearing, Wright—who’s spent most of his career in fossil fuels—made comments in support of nuclear energy and efforts to expand domestic generation in the near future. Asked what actions he would take as energy secretary to improve the development and deployment of SMRs, Wright said: “It’s a big challenge, and I’m new to government, so I can’t list off the five levers I can pull. But (I’ve been in discussions) about how to make it easier to research, to invest, to build things. The DOE has land at some of its facilities that can be helpful in this regard.”
G. C. Pomraning, Anil K. Prinja
Nuclear Science and Engineering | Volume 130 | Number 1 | September 1998 | Pages 1-17
Technical Paper | doi.org/10.13182/NSE98-A1986
Articles are hosted by Taylor and Francis Online.
We consider the problem of describing steady-state transport of a perpendicularly incident pencil beam of particles through a thin slab of material. The scattering is assumed to be described by the continuous slowing down approximation in energy and by the screened Rutherford formula in angle. For very small screening parameters, it is well known that the scalar flux, as a function of depth and radius, is described reasonably well by the classic Fermi-Eyges formula. However, realistic screening parameters, such as encountered in medical physics applications, are not small enough for this formula, which is Gaussian in radius, to be accurate. A correction to the spatial component of the Fermi-Eyges formula for screened Rutherford scattering is developed. This correction exhibits an algebraic, rather than exponential, falloff of the scalar flux with radius. Comparisons with benchmark Monte Carlo calculations confirm the inaccuracy of the scalar flux spatial distribution of the Fermi-Eyges formula for realistic screening parameters and demonstrate the good results obtained with the present formalism. Contact is made with earlier work by Molière.