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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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ANS Student Conference 2025
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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.”
Adnan A. Aswad, G. R. Dalton
Nuclear Science and Engineering | Volume 24 | Number 1 | January 1966 | Pages 49-59
Technical Paper | doi.org/10.13182/NSE66-A18123
Articles are hosted by Taylor and Francis Online.
The one-velocity time-independent neutron integro-differential transport equation is converted into an integral equation by the use of a homogeneous Green's function. The neutron flux, Green's function, and source are expanded in spherical harmonics. The integrations over the angles are carried out by the use of the spherical harmonic orthogonality relation. The net result is a set of coupled integral equations in the flux angular moments. Relations that give the Green's function angular moments are derived for any nonreentrant geometry and all boundary conditions applicable to the neutron transport equation. The conditions for which the scalar flux and some of the flux higher moments can be calculated exactly are discussed. Sample problems of unit slab cells that meet these conditions, are solved. The results are found to be in excellent agreement with those of the DS16 and the TRANVAR codes. A method to estimate the effect of the flux non-zeroth angular moments and the spatial truncation errors on the scalar flux is introduced. A sample problem of a heterogeneous unit slab cell is presented. It is found that the errors in the scalar flux due to neglecting the flux non-zeroth angular moments and the spatial truncation error are each of the order of 0.03% for this problem.
