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Dallas, TX|Hilton Anatole
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Breaking ground on a new approach to construction
The drive to Kairos Power’s reactor demonstration site in Oak Ridge, Tenn., is not only scenic—it’s historic. Nearly 85 years ago, roughly 30,000 construction workers transformed orchards and farmland into a key Manhattan Project site. Depending on your route, you may pass by one of the three gatehouses that were once military checkpoints controlling access to Atomic Energy Commission production facilities.
C. H. Blanchard
Nuclear Science and Engineering | Volume 3 | Number 2 | February 1958 | Pages 161-170
Technical Paper | doi.org/10.13182/NSE58-A25458
Articles are hosted by Taylor and Francis Online.
The spatial moments ,, and are calculated exactly for all energies below the source energy, for a point, isotropic source in an infinite, homogeneous medium in which there is no absorption and in which the scatterers scatter like hydrogen but with a 1/υ cross section. For a monoenergetic source these moments are approximately consistent with a diffusion (Yukawa) radial distribution of the very low energy neutrons. Integration over a fission-like source spectrum, exp (—αE), gives moments consistent with a radial distribution of the very low energy neutrons of the form of a first collision density, r-2 exp (—r/λ), but with a mean free path λ approximately twice the mean free path at the average source energy. The results are compared with those given by the first collision approximation.