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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
El Salvador: Looking to nuclear
In 2022, El Salvador’s leadership decided to expand its modest, mostly hydro- and geothermal-based electricity system, which is supported by expensive imported natural gas and diesel generation. They chose to use advanced nuclear reactors, preferably fueled by thorium-based fuels, to power their civilian efforts. The choice of thorium was made to inform the world that the reactor program was for civilian purposes only, and so they chose a fuel that was plentiful, easy to source and work with, and not a proliferation risk.
Yunzhao Li, Hongchun Wu, Liangzhi Cao
Nuclear Science and Engineering | Volume 174 | Number 2 | June 2013 | Pages 163-171
Technical Paper | doi.org/10.13182/NSE11-111
Articles are hosted by Taylor and Francis Online.
The isotropic simplified spherical harmonics (SP3) method is employed to cast the neutron transport equation into a coupled set of two equations each of which shares identical mathematical form with the neutron diffusion equation. An exponential function expansion nodal (EFEN) method is presented for an arbitrary triangular grid and implemented to solve the coupled SP3 equations. The EFEN method couples adjacent nodes by defining partial currents on each interface and expanding the detailed flux distribution within each node into a sum of exponential functions to obtain a response matrix between the incoming and outgoing partial currents and a neutron balance condition for each node to obtain the nodal average flux. Numerical results demonstrate that both keff and power distributions agree well with other codes. We find comparable accuracy in most situations, and the new method appears to be faster than the other codes even in cases where EFEN requires a finer unstructured mesh.
