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.”
V. V. Verbinski, C. Cassapakis, R. L. Pease, H. L. Scott
Nuclear Science and Engineering | Volume 70 | Number 1 | April 1979 | Pages 66-72
Technical Paper | doi.org/10.13182/NSE79-A18928
Articles are hosted by Taylor and Francis Online.
The validity of the silicon displacement cross section, D(E), was investigated by simultaneous measurements of neutron spectra (E) and of the accumulated damage D = K induced in 2N2222A transistors. The measured values of (E) were folded in with D(E) to obtain eq, the 1-MeV equivalent fluence for damage to silicon, and the ratios D/eq = K/eq ≡ K were obtained for diverse shapes of (E) to determine the stability of K to (E) variations. The value of K was seen to be constant (within 4 to 5%, 1σ) within roughly the same standard deviation as the D = K measurements for two modified reactor spectra that varied by as much as 1000% above a few MeV when normalized at the 0.2-MeV “threshold” of D(E). This helps substantiate the validity of D(E) in characterizing diverse neutron fields for radiation damage of a practical silicon transistor. Earlier studies with large-volume silicon diodes, for monoenergetic neutrons of 0.7 to 14 MeV, tend to corroborate the D(E) validity for transistors over this energy range. These results attest to the accuracy of the shape in terms of gross structure of D(E), which is governed by the accuracy of the ENDF/B-IV neutron cross-section evaluation used and of the Robinson functional representation of the Lindhard factor for determining the fraction of recoil-atom and charged particle kinetic energy that is available to cause displacements.