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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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.”
Franco Polidoro, Michael Flad, Werner Maschek
Nuclear Technology | Volume 191 | Number 3 | September 2015 | Pages 246-253
Technical Paper | Reactor Safety | doi.org/10.13182/NT14-97
Articles are hosted by Taylor and Francis Online.
In the case of a severe accident in a core resulting from unprotected loss of flow (ULOF) or unprotected transient overpower, damage can propagate from subassembly to subassembly and produce a whole-core–scale molten pool. Because the core is not in its most reactive configuration, a massive collapse of the molten material could result in a rapid supercritical condition with release of a large amount of energy. However, timely and sufficient fuel relocation outside the core by dedicated means could prevent any risk of recriticality and accident escalation. Based on a reference 1500-MW(electric) sodium-cooled fast reactor design, this paper describes the main results obtained in evaluating the recriticality potential of the European Sodium Fast Reactor (ESFR) core and conditions for its elimination during a ULOF-type transient. This study has been carried out in the frame of the Collaborative Project on European Sodium Fast Reactor of the 7th Framework Programme Euratom. The numerical analyses carried out in the present work allow one to estimate the amount of fuel mass that has to be removed from the core in order to maintain it in subcritical conditions, preventing the formation of a critical pool. Requirements for successful application of this approach, in terms of the negative reactivity insertion rate by fuel relocation and timing of discharge from the core, are derived.