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.
Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
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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Latest News
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.”
Kenji Yokoyama, Makoto Ishikawa
Nuclear Science and Engineering | Volume 178 | Number 3 | November 2014 | Pages 350-362
Technical Paper | doi.org/10.13182/NSE14-11
Articles are hosted by Taylor and Francis Online.
To provide a reactor physics benchmark for burnup reactivity coefficients, experimental data, showing the relationship between excess reactivity and accumulated thermal power acquired during the experimental fast reactor JOYO MK-I duty power operation in the late 1970s, have been evaluated and analyzed. To improve the prediction accuracy of nuclear characteristics through the use of integral experimental data, nominal values and uncertainties, including correlations of the experimental data, were evaluated. All possible uncertainty factors were evaluated and quantified by utilizing knowledge obtained after the MK-I duty power operation and calculation results based on the latest reactor physics analysis methods. Meanwhile, the present evaluated data have been reviewed and approved by the International Reactor Physics Experiment Evaluation Project, with the expectation that these data will be widely used. In the present paper, the evaluation of nominal values and uncertainties is described with a focus on the measurement technique uncertainty, which is a dominant uncertainty factor of the burnup reactivity coefficient. In addition, new analysis results of the benchmark problem are shown by the use of the latest Japanese evaluated nuclear data JENDL-4.0.