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
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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.”
S. N. Cramer
Nuclear Science and Engineering | Volume 141 | Number 3 | July 2002 | Pages 252-271
Technical Paper | doi.org/10.13182/NSE02-A2281
Articles are hosted by Taylor and Francis Online.
Radiation transport integrals containing both forward and adjoint fluxes are amenable to solution by the method of correlated coupling. Existing methods for surface integral coupling of forward and adjoint histories have been extended to volumetric coupling. Within the context of standard Monte Carlo usage, these integral solutions are exact, and the application to perturbation analysis requires no approximation. Coupled forward-adjoint history pairs are initiated at points selected uniformly in the perturbed volume. The energy and angular dependence of each history is dictated by the difference operator of the forward and adjoint transport equations, one equation for the perturbed system and one for the unperturbed system. The volume integral is accumulated as these history pairs score in the respective source or response regions. Some simple systems are analyzed showing that the new method gives comparable results, and a lower variance, as for existing methods. A review of current correlated coupling methodology is given, and suggestions for further study are outlined.