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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.
James R. Sheff, Robert W. Albrecht
Nuclear Science and Engineering | Volume 26 | Number 2 | October 1966 | Pages 207-221
Technical Paper | doi.org/10.13182/NSE66-A28163
Articles are hosted by Taylor and Francis Online.
The theory of space-dependent stochastic fluctuations is applied to several specific geometries to illustrate the space-dependence of the correlation and spectral-density functions. One-energy-group diffusion theory is used throughout to avoid clouding the geometric effects with other effects and to simplify the calculations. The first calculations are made in the infinite medium. The resulting cross-correlation and cross-spectral-density functions are shown to yield auto-correlation and spectral-density functions which differ strikingly from the usual point-reactor result. It is shown, however, that the point-reactor result is identical to the result obtained in an infinite reactor with a uniformly distributed detector. The effect of boundaries upon the fluctuations is examined from both the point of view of a finite detector and systems involving one or more boundaries. The case of the unreflected homogenous cubical reactor is solved. The results of cross-correlation and spectral-density calculations are displayed. The special case of the auto-correlation and spectral-density functions is compared to the point-reactor or space-independent result to show that significant departure from space independence is to be expected if detectors are placed away from axes of symmetry. This latter result obtains even when the extraneous source distribution is assumed to be fundamental mode.