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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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Fusion Science and Technology
Latest News
Fusion Energy Week begins today
Fusion is riding a surge of attention that began in December 2022 when researchers at Lawrence Livermore National Laboratory’s National Ignition Facility achieved fusion ignition. The organizers of Fusion Energy Week—a group called the U.S. Fusion Outreach Team—on the other hand, trace fusion development back 100 years to the doctoral research of Cecilia Payne-Gaposchkin, who discovered that stars, including our Sun, are mostly made of hydrogen and helium, which in turn led to the understanding that those elements are the “fuel” of potential fusion energy systems on Earth. In recognition of Payne-Gaposchkin’s birthday—May 10—the U.S. Fusion Outreach Team plans to hold a “grassroots celebration of fusion energy” May 6–10, 2024, and annually during the second week of May.
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.