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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
B. Wei-Teh Lee, R. E. Kaiser, J. T. Hitchcock, C. S. Russell
Nuclear Science and Engineering | Volume 65 | Number 3 | March 1978 | Pages 429-440
Technical Paper | doi.org/10.13182/NSE78-A27174
Articles are hosted by Taylor and Francis Online.
An indirect experimental technique for determining the expansion coefficient was developed to provide uncertainty estimates for expansion coefficient calculations. This technique uses an R, Z reactivity worth map synthesized from small-sample reactivity traverse measurements for major materials over the reactor core and blanket regions. The experimentally based expansion coefficients, representing the reactivity change due to uniform axial and radial expansion, are deduced by appropriately integrating measured worth profiles. This technique was evaluated in Phase A of the Zero Power Plutonium Reactor Assembly 5. Direct calculations of the expansion coefficients were performed, and results were compared with the experimentally determined values. The validity of the technique used to derive expansion coefficients from worth measurements was evaluated. It is concluded that the total expansion coefficients are reasonably well calculated; however, the calculated radial expansion coefficient was overestimated. Sources of possible systematic errors in the experimentally based values were studied. Based on the present experiment, an uncertainty of ±20% (90% level of confidence) on expansion calculations using ENDF/B-III data is estimated for a clean core configuration.