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
Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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.
Norman P. Baumann, Willard G. Winn
Nuclear Technology | Volume 72 | Number 3 | March 1986 | Pages 353-358
Technical Paper | Radiation Protection and Health Physics Practices and Experience in Operating Reactors Internationally / Analyse | doi.org/10.13182/NT86-A33774
Articles are hosted by Taylor and Francis Online.
A long-lived gamma source, containing 370 MBq of 232U (72 yr) and 110 MBq of 228Th (1.9 yr), was developed as a permanent replacement for neutron-activated 24Na (15-h) sources that have been used in a 2D(γ,n)1H tritiated water detector. The 228Th, which will build up to 340 MBq in 10 yr and then decay in equilibrium with 232U, emits copious 2614-keV gamma rays for the (γ, n) process. Competing (α, n) backgrounds are reduced by placing the uranium/thorium source in a gold matrix to provide threshold and coulomb barriers against the reaction. The detection limits (∼0.0l-ml D2O) for typical stainless steel pipes (∼2-cm diam) measured with the uranium/thorium source are almost as low as those for comparable 24Na sources, which do not produce (α,n) backgrounds. This minor sensitivity loss can be offset by longer counting times, if necessary. Lower personnel exposure is realized with the new source. Overall, the practical advantages of using a longer lived source strongly favor the use of 232U/228Th instead of 24Na.
