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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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Nuclear Science and Engineering
May 2025
Nuclear Technology
Fusion Science and Technology
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.
Jaeha Kim, Mohammad Abdul Motalab, Yonghee Kim, Gwangsoo Kim
Nuclear Technology | Volume 201 | Number 2 | February 2018 | Pages 138-154
Technical Paper | doi.org/10.1080/00295450.2017.1415087
Articles are hosted by Taylor and Francis Online.
The power coefficient of reactivity (PCR) needs to be negative to achieve the inherent safety of a reactor. However, the possibility that the PCR of CANada Deuterium Uranium (CANDU) reactors can be positive has been raised in recent studies. In such circumstances, there was an experimental approach on evaluating the PCR of CANDU in 2012 at an in-operation CANDU reactor, Wolsong Unit 2. In the evaluation, the PCR was indirectly measured by a method that required estimating the reactivity variation due to Xe, liquid zone controllers (LZCs), and fuel depletion based on the measurement data. In this study, the PCR of a CANDU was reevaluated by the same methodology with more proper and detailed methods to estimate all the factors in addition to some minor reactivity corrections. The estimation of Xe and LZC reactivity was performed by an in-house three-dimensional code and Serpent2 in addition to RFSP-IST. Furthermore, several short studies regarding the factors that result in uncertainty of the Xe/LZC reactivity estimation were done in detail. First, a method to determine 14 LZC levels at a certain time based on the measurement data was appropriately selected through determining the features of the measurement data. The influence of the power transient scheme and the impact of local refueling transients due to daily refueling of CANDU reactors on xenon reactivity estimation were also analyzed briefly. Finally, the PCR of the CANDU in operational conditions was evaluated to be ~0.5 pcm/%P on average at a measurement time of 5 to 20 min after the power perturbation.
