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M. Segev
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 229-235
Technical Note | doi.org/10.13182/NSE81-A21356
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An equivalence principle is developed for an infinite array of annular rods. The center of a rod is a moderator characterized by the sticking probability γ1. Surrounding the center is an annular absorber characterized by the radii R1 < R2. The rods are uniformly distributed in an outer moderator characterized by the sticking probability γ2. The escape cross section for the lattice is The factor a is an adjustable Bell factor.