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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.”
Povilas Poskas, Raimondas Kilda, Valdas Ragaisis, Terry M. Sullivan
Nuclear Technology | Volume 161 | Number 2 | February 2008 | Pages 140-155
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT08-A3919
Articles are hosted by Taylor and Francis Online.
Safety assessment of a near-surface repository of radioactive waste usually assumes a homogeneous distribution of activity within the vaults of the repository. However, in some cases there is radioactive waste, e.g., disused sealed sources, which should result in so-called "hot spots" when disposed of with other radioactive waste. An uneven distribution of waste activity is obtained in that case.The impact of heterogeneities in source distribution on radionuclide releases from a near-surface repository to the groundwater is analyzed in the paper. The conditions that stand for the application of homogeneous distribution of radioactive waste are revealed.The assessment has been performed using the methodology of the Improving Long Term Safety Assessment Methodologies for Near Surface Radioactive Waste Disposal Facilities (ISAM) study recommended by the International Atomic Energy Agency for the safety analysis of the near-surface repository. A description of the ISAM methodology and its application for the analysis of heterogeneity including a brief description of the disposal system of radioactive waste, the scenarios for the radionuclide migration, and the developed conceptual models are presented in the paper.The calculations have been carried out using the DUST and GWSCREEN computer codes, designed to simulate radionuclide transport. The modeling results for the case of homogeneous distribution of radioactive waste in the repository are considered. The impact of heterogeneities has been analyzed by comparing the modeling results of radionuclide transport for the heterogeneous case of waste distribution to the homogeneous case.
