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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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!
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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.”
Alain Hébert
Nuclear Science and Engineering | Volume 151 | Number 1 | September 2005 | Pages 1-24
Technical Paper | doi.org/10.13182/NSE151-1-24
Articles are hosted by Taylor and Francis Online.
Improvement of the lattice code component related to resonance self-shielding calculations is described. The proposed self-shielding model is based on a subgroup flux equation with probability tables, as implemented in the CALENDF approach of P. Ribon. A new type of correlated two-dimensional probability table is introduced for the representation of the slowing-down effect in the resolved energy domain. The resulting formalism makes possible a better representation of distributed self-shielding effects.A new numerical scheme is also proposed to represent the mutual shielding effect of overlapping resonances between different isotopes in the context of the Ribon subgroup equations. The interference effects between two resonant isotopes are represented by a correlated weight matrix also computed using a CALENDF approach. The model was designed with the primary goal of allowing the straightforward replacement of legacy self-shielding components in typical lattice codes to gain improved accuracy without any noticeable increase in CPU resources.Finally, a validation is presented where the absorption rates are compared with exact values obtained using a fine-group elastic slowing-down calculation in the resolved energy domain. Other results, relative to Rowland's pin-cell benchmarks, are also presented. The need to represent mutual shielding effects, at least for mixed-oxide fuel is demonstrated.