A team of researchers from the US Army Research Laboratory at Aberdeen Proving Ground, Md., described the results of a study on the application of laser photofragmentation/fragmentation detection spectrometry to energetic materials in the Oct. 20 issue of Applied Optics. The paper reports detection limits of parts per billion for the explosives PETN, TNT and RDX. The group illuminated the explosives with 227-nm pulses from an Nd:YAG-pumped dye laser with a frequency-doubling BBO crystal and analyzed the ion signatures of the vaporized material. The scientists said the high sensitivity of the laser spectroscopy at room temperature will permit its use for in situ, real-time detection.