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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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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Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Hongda He, J. Q. Dong, Zhixiong He, K. Zhao
Fusion Science and Technology | Volume 70 | Number 1 | July 2016 | Pages 54-61
Technical Paper | doi.org/10.13182/FST15-169
Articles are hosted by Taylor and Francis Online.
The density gradient of fast ions is the main driving force for fishbone instability that in turn results in fast ion loss. It is possible to reduce the instability by eliminating the density gradient of the fast ions by employing dual neutral beam injection (DNBI) in tokamak plasmas. The dispersion relation for the fishbone instability is applied to the case of DNBI with suitable fast ion distribution functions. The results show that the density distribution of fast ions of DNBI can bring about a stable window that is a range of values for the distance between the on-axis beam and the off-axis beam that yields an overall stabilization of the resultant fishbone mode. The width of the stable window increases linearly with the position of the safety factor q = 1 magnetic flux surface increasing. In addition, the width of the stable window becomes wider for a more peaked density profile of fast ions and keeps constant for a peaked enough density profile of fast ions. The growth rates of the fishbone modes dramatically decrease with the intensity ratio of off-axis neutral beam injection (NBI) and on-axis NBI, and the critical beta values of fast ions increase with the intensity ratio increasing. Fishbone modes can be avoided with DNBI, which may be an effective method to prevent fast ion loss resulting from fishbone instabilities.