The threat of nuclear proliferation remains a critical issue in our society. Prevention requires knowledge, and there is no greater indicator of the capability and intent of a nation than observation of actual detonation tests being conducted. Ground-based monitoring systems have proven to be very capable in identifying nuclear tests, and can provide somewhat precise information on the location and yield of the explosive device. Making these measurements, however, currently requires very expensive and bulky seismometers that are difficult to deploy in places where they are most needed. A high-performance, compact device can enable rapid deployment of large scale arrays, which can in turn be used to provide higher quality data during times of critical need. We are pursuing a design that is based upon a proven optical sensing modality, and will combine this interferometric transducer with a new mechanical system design in order to achieve the required sensor self-noise of 0.5 nano-g/Hz 1/2 , with a total dynamic range of more than 150 dB. This will be accomplished in a form factor that is approximately 1 cm 3 per axis, and a power consumption below 30 mW. These metrics would represent substantial advancements over the existing state of the art. Lower cost, smaller sensors will enable wide-scale deployment of sensor arrays, which will also greatly enhance our understanding of the earth and provide early-warning systems for earthquakes and tsunami. Slight variations in the sensor design will also find extensive use in oil and gas exploration.
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