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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.
Farzad Rahnema
Nuclear Science and Engineering | Volume 124 | Number 2 | October 1996 | Pages 320-326
Technical Paper | doi.org/10.13182/NSE96-A28581
Articles are hosted by Taylor and Francis Online.
Expressions are derived for the first-order change in the fundamental eigenvalue of the neutron transport equation due to a perturbation in the boundary condition of the system. The perturbation formula is derived in the context of the energy-dependent transport theory and its diffusion approximation. Numerical examples are given in both transport and diffusion theory.
