Standoff Explosive Particle Spectrometer (SEPS)

US Government Agencies have recognized the need for checkpoint inspection technology at airports to deter the transporting of destructive weapons or illegal materials into or within the United States since the early 1970s. Since 9/11 the Government has been vigorously supporting development and deployment of ever improving policies and technologies to provide an ever-present, yet non invasive, safeguard for our citizens. Among the tools employed for checkpoint screening, chemical trace detectors enabling rapid analysis of microscopic trace particles on a person or package have been a very effective technology. Yet, trace detectors are limited by the difficulty of transporting particles to the sensor since explosive molecules are extremely nonvolatile or sticky. This has traditionally required taking swipes of the target person or bag and heating the swab for analysis in an Ion Mobility Spectrometer (IMS) instrument. DHS is seeking stand off detection of trace explosive particle without the need for collecting the particles in an IMS (or Time of Flight Mass Spectrometer) sensor. To respond to this situation SLI is proposing an innovative exploitation of the Coherent Anti-Stokes Raman Spectroscopy (CARS) technology to develop a Standoff Explosive Particle Spectrometer (SEPS). Data and modeling in Phase I will enable SLI to expand on previous laboratory techniques to optimize the technology for detecting a wide range of explosive species in real-world screening environments. In this application, the safety of both passengers and operators must be considered and regulatory safety requirements for human exposure must be met.