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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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Rahim Nabbi
Nuclear Technology | Volume 64 | Number 1 | January 1984 | Pages 5-13
Technical Paper | Nuclear Safety | doi.org/10.13182/NT84-A33321
Articles are hosted by Taylor and Francis Online.
The core dynamic analysis of an anticipated heat removal transient without scram in a high-temperature gas-cooled reactor has indicated that in case of a failure of core cooling, the reactor undergoes a selfshutdown after 1 min because of its negative temperature coefficients of reactivity. If the decay heat removal system operates according to plant specification, recriticality, and thus nuclear power generation, occurs. However, the maximum rise in fuel elements temperature is limited to 50°C due to the high heat capacity of the core. Without taking into consideration the effect of xenon feedback on the neutron kinetics, a new steady core state is established after 2 h in which the fuel temperature and gas outlet temperature at the lower core edge are 195°C higher than in normal operation. Due to transient xenon poisoning, a rise in gas outlet temperature only occurs during the first 70 min and amounts to 70°C. For this reason undesirable transient strains on the components connected behind the core are not expected. A slow xenon buildup during the first hour ensures a long-term subcriticality of the reactor. Without any contribution from the shutdown system, this leads to a decrease in nuclear power and thus to core cooling with functioning decay heat removal.