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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.
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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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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.”
Bobby E. Leonard
Nuclear Technology | Volume 104 | Number 1 | October 1993 | Pages 89-105
Technical Paper | Radiation Protection | doi.org/10.13182/NT93-A34872
Articles are hosted by Taylor and Francis Online.
The use of induced time-dependent 222Rn behavior to determine source rate magnitudes, ventilation rates (air change rates), and other parameters that affect 222Rn and progeny levels and exposure to building occupants is investigated. When the subject space is purged and the buildup (seepage) back into the space is measured, theoretical, normalized equations show a unique, one-to-one correspondence of the 222Rn and particulate progeny temporal levels to the air change rate in the space. The Bateman equations have been solved in closed form for 222Rn and progeny in air and trapped on a filter under these conditions. A total of 28 measurements of the time-dependent behavior of radon progeny for two test facilities [one with a constant air change rate and one with a constant National Institute of Standards and Technology (NIST)-calibrated source] and four residential dwellings were made. The results were compared with theory and with air change rate measurements made by anemometer flow rates and by the conventional method (SF6 decay). For a factor of 2 range in air change rates in the NIST constant source case, the agreement with the SF6 method air change rate was within ±10.6% standard deviation and agreement with the NIST source magnitude of 37.0 ± 1 kBq was within ±4.9% standard deviation. Agreement to within ±17.7% standard deviation was obtained on determination of air change rates for the residential dwellings. Based on the airborne concentrations and air change rates, source emanation rate magnitudes were obtained. Analyses of the results are presented in detail, and factors affecting the accuracy and feasibility of the method are identified.
