Sulfur hexafluoride detection by Radar Resonance Enhanced Multiphoton Ionization
In this study, we have demonstrated the stand-off detection of sulfur hexafluoride by the Radar resonance multi-photon ionization process. In order to obtain a well defined spectral signature, the sulfur hexafluoride molecules are first dissociated by a focused pulsed Nd:YAG laser to sulfur difluoride molecules, which are then ionized by a pulsed, frequency tunable, narrow linewidth laser emitting in the ultraviolet. At the wavelength 269.5 nm, a concentration of 10 % of sulfur hexafluoride has been detected and the spectral signature shows some overlap with a carbon dioxide resonant spectral line. At 322.45 nm, we achieve better spectral definition. Based on successes using a similar approach for trace nitric oxide detection, we expect to be able to extend this approach to the detection of trace levels of SF6in the atmosphere for greenhouse gas monitoring. 2011 by Princeton University. Published by the American Institute of Aeronautics and Astronautics, Inc.