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Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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.”
P. Savva, S. Chatzidakis, M. Varvayanni, A. Ikonomopoulos, N. Chrysanthopoulou, N. Catsaros, M. Antonopoulos-Domis
Nuclear Technology | Volume 188 | Number 3 | December 2014 | Pages 322-335
Technical Note | Fission Reactors | doi.org/10.13182/NT13-108
Articles are hosted by Taylor and Francis Online.
Research reactors are used for many applications: material testing; radioisotope production; beam-line applications for material research; nuclear transmutation doping; neutron activation analysis; neutron radiography experiments; fuel waste management; and other neutron and nuclear material related quantities, features, and research areas of interest. Each application requires enhanced neutron fluxes in a specific section of the energy spectrum; therefore, appropriate irradiation positions in the core or an appropriate configuration of the beam line need to be chosen. In several cases the required flux exceeds the maximum value that can be obtained in the existing irradiation positions of the operating reactor core, but the desired neutron flux amplification through the reactor power upgrade would require large-scale transformations, high costs, and long shutdown periods. With the creation of a flux trap at a central core position in the open pool Greek Research Reactor (GRR-1), a noticeable local increase of the thermal neutron flux was achieved, compared to the irradiation channels at peripheral core positions. In the present technical note, calculational and measurement results concerning the original core modification are presented, while the possibility of larger sample irradiation at higher thermal neutron flux in the GRR-1 is investigated. The presented results are based on deterministic and stochastic neutronic calculations with numerical models validated using measurements conducted for the original flux trap. The work is completed with a thorough thermal-hydraulic analysis to evaluate the impact of the proposed modifications to reactor operation. The study showed that the flux trap enlargement with complete removal of a central control fuel assembly increases the maximum thermal neutron flux by ∼41%, while further removal of the neighboring fuel assembly leads to an average flux increase of ∼45%, thus offering capabilities for extended reactor utilization such as additional isotope production.