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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.”
M. L. Williams
Nuclear Science and Engineering | Volume 108 | Number 4 | August 1991 | Pages 355-383
Technical Paper | doi.org/10.13182/NSE90-33
Articles are hosted by Taylor and Francis Online.
A general theory is developed to describe the mechanism by which the response observed on a detector propagates throughout a system. The response is transferred between a particle source and the detector by special particles called contributons. The distribution in phase-space of the response carried by contributons defines a new quantity called the “response continuumwhich depends on solutions to the forward and adjoint Boltzmann equations. A transport equation for the response distribution is derived, and properties of the response continuum are discussed. The response concentration is described by the contributon response density and flux, which are used to locate regions containing large amounts of potential response contribution. The flow of response through space is described by streamlines of a vector field called the “response current.” This field is related to two new variables called the “response potential” and “vorticity,"respectively. Sample results are presented for “contributon dipole” configurations. A spherical harmonic expansion of the angular flux is given to describe directional characteristics of the response continuum. The “contributon slowing-down equation” is derived to describe the simultaneous transfer of response through space and energy. A new contributon Monte Carlo method to simulate response transport is discussed.