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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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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
J. A. Favorite, W. M. Stacey, Jr.
Nuclear Science and Engineering | Volume 126 | Number 3 | July 1997 | Pages 282-292
Technical Paper | doi.org/10.13182/NSE97-A24481
Articles are hosted by Taylor and Francis Online.
A new variational estimate for dynamic reactivity that accounts for delayed neutron holdback is introduced and adapted for use with the improved quasistatic (IQS) method. Numerical tests on a large light water reactor model indicate that the computational effort required with the IQS method can be reduced by a factor of 3 to 4 by using this new variational estimate of dynamic reactivity. With comparable computational effort, the accuracy of the standard IQS method, which uses the flux shape interpolation/recomputation procedure and a first-order estimate of static reactivity, can be improved by using a standard variational estimate without the flux shape interpolation/recomputation procedure, and it can be further improved by using the new variational estimate of dynamic reactivity.
