ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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!
Latest Magazine Issues
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
EPA administrator Lee Zeldin talks the future of nuclear
In a recent interview on New York radio station 77 WABC, administrator of the Environmental Protection Agency Lee Zeldin talked with host John Catsimatidis about the near-term future of the domestic nuclear industry and the role the EPA will play in the sector.
Catsimatidis kicked off the interview by asking if the U.S. will be able to reach total energy independence. Zeldin responded by saying that decreasing energy dependence on other countries, especially adversaries, was a top priority for him and the Trump administration.
Shoji Watanabe, Kojiro Nishina
Nuclear Science and Engineering | Volume 86 | Number 3 | March 1984 | Pages 283-296
Technical Paper | doi.org/10.13182/NSE84-A17557
Articles are hosted by Taylor and Francis Online.
A stability analysis using a one-group model is presented for a coupled-core system. Positive prompt feedback of a γpj form is assumed, where pj is the fractional power variation of core j. Prompt power variations over a range of a few milliseconds after a disturbance are analyzed. The analysis combines Liapunov's method, prompt jump approximation, and the eigenfunction expansion of coupling region response flux. The last is treated as a pseudo-delayed neutron precursor. An asymptotic stability region is found for pj. For an asymmetric flux variation over a system of two coupled cores, either pI or pII can slightly exceed, by virtue of the coupling effect, the critical value (β/γ − 1) of a single-core case. Such a stability region is increased by additional inclusion of the coupling region fundamental mode in the treatment. The coupling region contributes to stability through its delayed response and coupling. An optimum core separation distance for stability is found.
