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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.
Margaret A. Marshall
Nuclear Science and Engineering | Volume 178 | Number 4 | December 2014 | Pages 479-495
Technical Paper | doi.org/10.13182/NSE14-43
Articles are hosted by Taylor and Francis Online.
A series of small, compact critical assembly experiments was completed from 1962 to 1965 at Oak Ridge National Laboratory's Critical Experiments Facility in support of the Medium-Power Reactor Experiments program. Initial experiments, performed in November and December 1962, consisted of a core of unmoderated stainless steel tubes surrounded by a graphite reflector. Later experiments included beryllium-reflected assemblies with the fuel in a 1.506-cm triangular lattice and in seven-tube clusters. Once the critical configurations had been achieved, various measurements of reactivity, relative axial and radial activation rates of 235U, and cadmium ratios were performed. The critical configurations, the cadmium ratio, and activation rate measurements for the beryllium-reflected 1.506-cm-array critical configuration have been evaluated and are described in this paper. It was found that these measurements are acceptable as benchmark experiments and have been included in the International Handbook of Evaluated Reactor Physics Benchmark Experiments and the International Handbook of Evaluated Criticality Safety Benchmark Experiments.