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
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
April 2025
Fusion Science and Technology
Latest News
General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Huseyin Atilla Ozgener
Fusion Science and Technology | Volume 61 | Number 1 | January 2012 | Pages 281-286
Modeling and Simulations | Proceedings of the Fifteenth International Conference on Emerging Nuclear Energy Systems | doi.org/10.13182/FST12-A13433
Articles are hosted by Taylor and Francis Online.
The criticality eigenvalue problems of both multigroup diffusion and transport theories have slow rates of convergence when the dominance ratio is close to one. This situation arises especially in the analysis of loosely coupled reactor systems and necessitates the use of acceleration techniques. The coarse mesh rebalance method constitutes one of the prominent ones of such acceleration schemes. The coarse mesh rebalance method has been used in the acceleration of direct diffusion criticality eigenvalue problems. In this study, this acceleration method is utilized also in the solution of adjoint diffusion problems in spherical geometry. The efficiency of the acceleration method is assessed through numerical experiments and certain conclusions have been drawn regarding the use of coarse mesh rebalance in such problems.
