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DTRA’s advancements in nuclear and radiological detection
A new, more complex nuclear age has begun. Echoing the tensions of the Cold War amid rapidly evolving nuclear and radiological threats, preparedness in the modern age is a contest of scientific innovation. The Research and Development Directorate (RD) at the Defense Threat Reduction Agency (DTRA) is charged with winning this contest.
M. Segev
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 229-235
Technical Note | doi.org/10.13182/NSE81-A21356
Articles are hosted by Taylor and Francis Online.
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.
