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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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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.
K. Ueki, A. Ohashi, N. Nariyama, S. Nagayama, T. Fujita, K. Hattori, Y. Anayama
Nuclear Science and Engineering | Volume 124 | Number 3 | November 1996 | Pages 455-464
Technical Paper | doi.org/10.13182/NSE124-455
Articles are hosted by Taylor and Francis Online.
Three types of experiments with a 252Cf neutron source are proposed to evaluate systematically the neutron shielding effects of a material. The type 1 experiment deals with each shielding material alone, the type 2 experiment combines a shielding material and a structural material, and the type 3 experiment constructs the optimization with the materials used in the type 2 experiment. In the stainless steel (SS) + polyethylene shielding system, because of the location of the SS slabs at the source side, the tenth layer of the polyethylene becomes approximately one-half the value as when the polyethylene is employed alone. This is the enhancement effect of the SS. In the type 3 experiment, the total thickness of the SS + polyethylene shielding system is 40 cm, and the total thicknesses of the SS and the polyethylene slabs are fixed at 25 and 15 cm thick, respectively. The minimum total dose-equivalent rate (neutron + secondary gamma rays) is observed when the polyethylene slabs are located at a 20-cm depth from the source side, with an arrangement of 20-cm-thick SS + 15-cm-thick polyethylene + 5-cm-thick and SS, and with a ratio of the maximum to the minimum dose-equivalent rate of 2.5. The shielding optimization can be constructed by combining the materials having different shielding characteristics. The experimental results of the three types of experiments are reproduced fairly well by using the continuous-energy Monte Carlo code MCNP 4A with a next-event surface crossing estimator.
