Stand-off Detection of Alternative Signatures of Radiation

Prevention of the smuggling of radioactive material into the United States to be used by terrorists in a nuclear weapon or in a radiological dispersal device, such as in a"dirty bomb", is a key national security objective. It is desirable to have a system capable of stand-off detection to monitor and rapidly alert the presence of covert nuclear materials. Tanner proposes to develop a compact laser based sensor system to detect the presence of alternative signatures of radiation. Radiochemical reactions between ionizing radiations and the atmosphere lead to the production of radicals such as ozone (O3) and various oxides of nitrogen. Concentration of these species above normal background levels is an alternative signature of radiation. Tanner will develop a stand-off detection system that can search for covert nuclear materials via a detection of the presence of trace quantities of ozone. In Phase I of this effort, we will demonstrate the stand-off detection of trace quantities of ozone over distances of 1 meter. In Phase II, these results will be scaled to design and develop a compact prototype stand-off detection system that is capable of operation over distances as long as 20 m and with automatic data collection, analysis and display of relevant data.