ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
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.
J. E. Morel, J. M. McGhee
Nuclear Science and Engineering | Volume 116 | Number 2 | February 1994 | Pages 73-85
Technical Paper | doi.org/10.13182/NSE94-A21484
Articles are hosted by Taylor and Francis Online.
A synthetic scheme for accelerating the convergence of the fission source in time-dependent multigroup even-parity Sn calculations with downscatter is described. The low-order operator associated with this scheme is a one-group diffusion operator. Thus, this scheme can be thought of as a variant of diffusion synthetic acceleration. A Fourier analysis of this scheme is performed, which indicates that it is unconditionally effective for a spatially infinite model problem. Computational results are presented that show excellent performance of the method in three-dimensional calculations. Although this method is derived for the even-parity Sn equations, it can easily be generalized for application to the standard first-order Sn equations. The accelerated iteration equations for both the even-parity and first-order Sn equations are given, but only the even-parity algorithm is computationally tested.
