Thrust 2: Explosives Sensors

The focus of this thrust is to research the basic science of new sensing modalities, create new sensors which exploit conventional sensing modalities, configure existing sensors, and develop and implement interpretation strategies for each separate sensor to best detect and identify explosive-related threats. The various individual sensors will be combined into hybrid systems that use multiple modalities in Thrust F3, "Explosives Sensor Systems"

The sensors discussed in this section include infrared thermography and multispectral emission spectroscopy; microwave, millimeter-wave and terahertz imaging to sense geometric size and shape as well as dielectric composition; chemical mass spectroscopy; and electromagnetic sensors to identify unintentional electronic emissions (see [Moore '07]). The sensors will operate in three suspected target regimes: 1) distant targets (10 m to >100 m), requiring stand-off detection of hazards while they are still far enough away to minimize the threat, and 2) mid-range or close-in targets (3 to 10 m) which offer the possibility of enhanced sensing discrimination without explicitly surrounding the target, and 3) intimately near targets (<3 m) which can be non-invasively examined with portal sensors. The first is preferable, but is most challenging because of the decreased sensitivity of sensors, increased clutter from multiple individuals, vehicles, buildings, and terrain. Our plan is to consider a multi-layer approach, using the best sensors, with the stand-off sensor alarming when there is a slight possibility of potentially hazardous abnormality, which is then ruled out or confirmed with close-in sensors.

> F2-A Detection of Explosives Using Hyperspectral Imaging

> F2-B Millimeter-Wave Standoff Detection of Concealed Explosives

> F2-C Physics of Terahertz Wave Generation and Detection in Gases

> F2-D Intelligent Mass Spectrometer for Identifying Explosives and Chemical Weapons

> F2-E Detection of Electronically Initiated Explosive Devices

> F2-F Remote Raman and Infrared Detection of Explosives and Other Threat Agents