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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Michael Jarrett, Brendan Kochunas, Edward Larsen, Thomas Downar
Nuclear Science and Engineering | Volume 193 | Number 12 | December 2019 | Pages 1291-1309
Technical Paper | doi.org/10.1080/00295639.2019.1627176
Articles are hosted by Taylor and Francis Online.
A new method for calculating anisotropic radial transverse leakage (TL) in a two-dimensional (2D)/one-dimensional (1D) transport method is derived and implemented in MPACT. This method makes use of parity in the polar angle only to form the 2D transport equations for the 2D/1D method. The even-parity component is solved on a fine mesh using the method of characteristics (MOC), while the odd-parity component is solved on a coarse mesh using S. The anisotropic radial TL on the coarse cell boundaries is calculated by combining the even- and odd-parity components. The new method is faster than a similar previous method because it delegates half of the work required to calculate the solution of the 2D transport problem to a coarse-mesh S solver, which is more than ten times faster than the fine-mesh MOC solver. The results show that the accuracy of the new method is equivalent to that of the previously implemented method for anisotropic TL, with a significant speedup. With azimuthally isotropic TL, the new method reduces the computational overhead compared to the standard method from 58% to 5% for the three-dimensional (3D) C5G7 benchmark problems. With azimuthally anisotrop\ic TL using Fourier expansion, the new method reduces the overhead from 84% to 37%. This is important because the accuracy of the 2D/1D method is limited by the isotropic TL approximation. With anisotropic TL, the accuracy of 2D/1D is equivalent or comparable to 3D transport, but there is a significant computational cost associated with calculating the anisotropic TL. The method presented provides a faster way to calculate the anisotropic TL, giving the 2D/1D method significantly increased accuracy with only a modest increase in computational requirements compared to isotropic 2D/1D.