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
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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.”
Scott D. Ramsey, Roy A. Axford
Nuclear Science and Engineering | Volume 166 | Number 1 | September 2010 | Pages 48-57
Technical Paper | doi.org/10.13182/NSE09-64
Articles are hosted by Taylor and Francis Online.
We implement direct and approximate local sensitivity analysis techniques within the context of stochastic point kinetics neglecting delayed neutrons and external neutron sources. After reviewing the derivation of certain probabilities that the neutron population in a nuclear assembly is exactly zero [probabilities of extinction (POEs)], we consider their dependence on physical data. We subsequently focus on fission number distribution dependence and draw comparisons between two different data sets. As various POEs are dependent upon these data through the solution of a nonlinear ordinary differential equation, local sensitivity analysis provides a useful means through which to assess the effects of data reevaluation. We first conduct this analysis generally (though approximately) using Gâteaux-derivative methodology. Following the generalized developments, exact and approximate results for 235U are presented with a discussion concerning important consequences related to criticality safety.
