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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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 News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
To hear more insights from this talented group of young professionals, watch the “40 Under 40 Roundtable: Perspectives from Nuclear’s Rising Stars” on the ANS website.
Anil Kumar
Nuclear Science and Engineering | Volume 81 | Number 1 | May 1982 | Pages 66-74
Technical Paper | doi.org/10.13182/NSE82-A19595
Articles are hosted by Taylor and Francis Online.
The neutron collision escape probability from a medium depends on the shape of spatial distribution of the source. The case of a uniform or flat source distribution has been investigated extensively from time to time. In the present work, the case of bare homogeneous reactor assemblies having a centrally peaked neutron source distribution has been analyzed for predicting collision escape probability as a function of assembly size measured in terms of the optical mean chord length . An approximation, known as the modified Wigner rational approximation, is derived and is given by where pE(W) stands for the collision escape probability from a bare homogeneous reactor assembly; ϵ1 and ϵ2 are geometry-dependent parameters. These parameters have been determined for infinite slab, infinite cylinder, sphere, cube, and finite cylinders of height-to-diameter ratio varying from 0.1 to 20. It is shown that it is possible to predict the collision escape probability within approximately ±2% of the exact value for , ranging from 0 to 20 mean-free-paths (mfp). Generally, for a given the collision escape probability value for the centrally peaked source is lower than that for the uniform source. But it is found that for very thin infinite slab assemblies of optical mean chord length 1.5 mfp, the collision escape probability for centrally peaked source distribution is higher than that for uniform source distribution. The reason for this anomaly is discussed.