Remote Raman spectroscopy of explosive precursors

Deep ultraviolet Raman spectroscopy measurements have been performed at the German Aerospace Center (DLR) with the aim of detecting traces (mu g range) of explosive precursors. In this study, a backscattering Raman system was setup and optimized to detect urea, sodium perchlorate, ammonium nitrate, and sodium nitrate at a 60-cm short-range remote detection. The sample was tested at 264-nm ultraviolet laser excitation wavelength to experimentally observe any possible trace over textiles samples. For each colored sample textile, Raman spectra were acquired and no background fluorescence interference was observed at this laser excitation wavelength. Detection limits and system sensitivity with an acquisition time up to 3 s for microgram traces are presented. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License.

Automated summary

Deep ultraviolet Raman spectroscopy was performed to detect traces of explosive precursors in the microgram range at a short-range remote detection. The Raman system was optimized to detect specific compounds like urea, sodium perchlorate, ammonium nitrate, and sodium nitrate with no background fluorescence interference observed during the experiments. Detection limits and system sensitivity for microgram traces were presented with an acquisition time of up to 3 seconds.