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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.
E. T. Cheng, C. W. Maynard, W. F. Vogelsang, A. C. Klein
Nuclear Technology | Volume 45 | Number 1 | August 1979 | Pages 77-98
Technical Paper | Reactor | doi.org/10.13182/NT79-A32287
Articles are hosted by Taylor and Francis Online.
One of the characteristics of a compact tokamak fusion reactor such as NUWMAK is high power density (∼10 MW/m3) and thus high neutron wall loading (∼5 MW/m2). The most crucial design requirements for a tokamak fusion reactor blanket and shield are (a) adequate tritium breeding ratio (>1.10), (b) high blanket energy multiplication (≥1.2), (c) adequate magnet protection, and (d) low radioactivity. The magnet protection criterion for a compact reactor is particularly essential in the inner region of the torus close to the toroidal axis because of limited space availability for shielding. A very effective shielding material such as tungsten must be used for this purpose. The design requirements have been satisfied by the selection of blanket and shielding materials as well as their zone thicknesses and heights. The nucleonic design features of the NUWMAK are as follows. A tritium breeding ratio of 1.54 is obtained. Li62Pb38 eutectic is used as the breeding and thermal energy storage material. The total nuclear heating in the blanket and shield is ∼17.2 MeV per deuterium-tritium neutron. The performance of the superconducting magnet will be satisfactory for more than 2 yr of continuous operation through the use of a 35-cm-thick tungsten shield that extends 2.5 m above the midplane on the inboard part of the torus. The radioactivity is lowered by using a titanium alloy as the structural material and large amounts of lithium lead as the blanket material. One day after shutdown, the dose rate outside the outer shield drops below 2.6 mrem/h, and it is favorable to hands-on shift maintenance.
