Remote Raman detection of chlorine with deep UV excitation wavelengths

Abstract

Deep ultraviolet Raman spectroscopy measurements have been performed at the German Aerospace Center (DLR) to detect chlorine gas. In this study a remote Raman set up was optimized to detect chlorine gas at a distance of 60 cm. Several ultraviolet laser wavelengths (224, 232, 235 nm respectively, 2.5 mJ/pulse at 10 Hz) were changed to experimentally observe the highest possible signal to noise ratio. For each tested excitation wavelength, chlorine spectra were successfully detected. Detection limits in acquisition times for a 0.36 bar chlorine sample are discussed. A possible solution to avoid spectral overlapping of the background material with the sample is presented.