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NEUP honors young ANS members with R&D awards
Each year, the Department of Energy’s Nuclear Energy University Program (NEUP) recognizes graduate and undergraduate students for their innovative nuclear energy research. The winners of the Innovations in Nuclear Energy Research and Development Student Competition (INSC) receive honoraria along with travel and conference opportunities, including the chance to present their publications at the annual American Nuclear Society Winter Conference & Expo.
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.