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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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 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.
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.