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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
M. Segev
Nuclear Science and Engineering | Volume 36 | Number 1 | April 1969 | Pages 59-66
Technical Paper | doi.org/10.13182/NSE69-A18857
Articles are hosted by Taylor and Francis Online.
An approximate analytic solution to the infinite-medium slowing down equation is obtained for a weakly absorbing mixture of isotopes. It derives from a moment expansion of the integral equation and, by truncation, involves the average lethargy gain and the average square of the lethargy gain per collision in the mixture. It applies to the vicinity of a resonance if the isotope masses are not much different from each other or if the scattering power (ξ ΣS) of the resonant isotope at the resonance peak is much higher than the scattering power of the background. It offers a simple description of the strong fluctuations in the collision density caused by wide or strong resonances of light and structural elements in fast mixtures. An important application of the theory is the evaluation of group cross sections. The theoretical estimate of the group removal cross section was compared with numerically-exact values and a discrepancy of a few percent was found.
