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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
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Nuclear Science and Engineering
November 2024
Nuclear Technology
Fusion Science and Technology
Latest News
A proactive approach to reactor vessel aging management
Unit 2 at the Prairie Island nuclear power plant near Red Wing, Minn., underwent an outage in fall 2023, which included extensive work on the reactor vessel using a novel approach to replace baffle-former bolts and lower radial clevis insert bolts. The work relied on extensive analysis beforehand to determine which bolts to replace such that only the new bolts were structurally credited for performance of their safety function. This proactive approach eliminated the need for costly contingencies associated with inspections.
R. Pampin, A. Cubi, N. Taylor, M. Fabbri, P. Martinez-Albertos, P. Sauvan, Y. LeTonqueze
Fusion Science and Technology | Volume 80 | Number 8 | November 2024 | Pages 1012-1023
Research Article | doi.org/10.1080/15361055.2023.2278375
Articles are hosted by Taylor and Francis Online.
Photoneutrons may be generated in beryllium by energetic gamma rays via the reaction 9Be(γ,n)8Be. In ITER, the beryllium layer of the first wall may be the source of such photoneutrons. During plasma operation, these are of insignificant intensity compared with D-T neutrons from the plasma, but after shutdown, photoneutrons produced by decay gammas from neutron-activated material may be significant enough to impact sensitive electronic components in diagnostic or remote handling equipment that would not otherwise be exposed to neutrons.
Studies have been performed to characterize the expected photoneutron source and to evaluate the fluxes arising in detailed three-dimensional models of the ITER tokamak. The results show photoneutron fluxes approaching 105 n/cm2·s within the vessel and up to 103 n/cm2·s elsewhere within the bioshield 14 days after shutdown. When first-wall panels are being transported to the Hot Cell Facility after irradiation, a photoneutron flux exceeding 104 n/cm2·s within the transfer cask is predicted 21 days after shutdown. The peak values in the surrounding building are between 102 and 103 n/cm2·s at the same time.