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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
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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Nuclear Science and Engineering
March 2025
Nuclear Technology
Fusion Science and Technology
February 2025
Latest News
WEST claims latest plasma confinement record
The French magnetic confinement fusion tokamak known as WEST maintained a plasma in February for more than 22 minutes—1,337 seconds, to be precise—and “smashed” the previous record plasma duration for a tokamak with a 25 percent improvement, according to the CEA, which operates the machine. The previous 1,006-second record was set by China’s EAST just a few weeks prior. Records are made to be broken, but this rapid progress illustrates a collective, global increase in plasma confinement expertise, aided by tungsten in key components.
Sheng-Chi Lin, J. C. Robinson, D. L. Selby
Nuclear Science and Engineering | Volume 67 | Number 1 | July 1978 | Pages 61-73
Technical Paper | doi.org/10.13182/NSE78-A27237
Articles are hosted by Taylor and Francis Online.
The Lewins variational functional was employed to formulate approximations to the neutron detection efficiency, which is a parameter required in the measurement of reactivity by the modified source multiplication technique. In particular, a conventional variational method, a variational extrapolation method, a variational interpolation method, and a multi-reference-state variational method were developed for estimating neutron detection efficiency. Results obtained using the various approximate techniques in one and two dimensions were compared with results from exact formulations. The results obtained using the multi-reference-state variational method in all cases and the variational interpolation method in most cases compared very favorably (discrepancies <5%) with results from the exact calculations. The approximate techniques can be cast in a form where very simple calculational capabilities are all that are required to obtain detection efficiency for any given (but arbitrary) subcritical state. Therefore, we conclude that the methodology developed herein would be applicable to on-line applications using minimal computer capabilities.
