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
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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.”
B. Rocca-Volmerange
Nuclear Science and Engineering | Volume 64 | Number 3 | November 1977 | Pages 779-784
Technical Note | doi.org/10.13182/NSE77-A27107
Articles are hosted by Taylor and Francis Online.
This Note expands on a previously communicated synthetic slowing down model to determine the neutron spectra in fast reactors. Based on a polynomial approximation, the model accuracy increases with the order of the expansion. It is, in fact, a generalization to N terms of the one-term classical slowing down models such as those of Fermi, Wigner, and Greuling-Goertzel. Equivalent to the classical and synthetic expression of our QN model, this Note proposes a determination of a “differential” expression of the model, allowing the calculation of a set of functions approximating the kernel Σs(u′ → u). To be used in reactor codes, the spectrum determination has to he associated to a spatial resolution; the second part of this Note is devoted to the adaptation of the QN method to the collision probability approximation or the calculation of a spatial Green's function, to obtain a flux (r,E). The applications in the isotropic collision approximation can be extended to the linearly anisotropic approximation, and various results that demonstrate the validity of the method are given.