We describe the coupling of a magneto-optical trap to amass separator for the ultra-sensitivity detection of selected radioactive species. As a proof of principle test, we have demonstrated the trapping of approximately 6 million $_82)Rb atoms using an ion implementation and heated foil release method of introducing the sample into a trapping cell with minimal gas loading. Gamma-ray counting techniques were used to determine the efficiencies of each step in the process. By far the weakest step in the process is the efficiency of the optical trap itself. Further improvements in the quality of the nonstick dryfilm coating on the inside of the trapping cell and the possible use of larger diameter laser beams are indicated. In the presence of a large background of scattered light, this initial work achieved a detection sensitivity of approximately 4,000 trapped atoms. Improved detection schemes using a pulsed trap and gated photon detection method are outlined. Application of this technology to the areas of environmental monitoring and nuclear proliferation are foreseen.
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