Cyanide Molecular Laser-Induced Plasma Spectroscopy

Abstract

This work communicates recent measurements of CN in laser-induced plasma. The main goals and objectives comprise (a) exploring CN measurement using optical emission spectroscopy in optical breakdown plasma; (b) determining the effects of laser-induced shockwave for time delays of the order of 1 μs; (c) evaluating the spatial distribution of CN signals; (d) inferring CN temperature distribution; and (e) associating recorded shadowgraphs with laser-spectroscopy results. Q-switched, 150 mJ, 6 ns pulsed Nd:YAG laser radiation at the fundamental wavelength of 1064 nm is used to generate micro-plasma in a gas mixture with ultra-high purity nitrogen and research grade carbon dioxide. The CO2 to N2 molar ratio is 1 to 1 for the gaseous mixture near atmospheric pressure flowing through the chamber. Optical emissions are dispersed by a 0.64-m Czerny-Turner spectrometer and an intensified charge-coupled device records the data along the wavelength and slit dimensions. The analysis utilizes Abel integral inversion techniques for determination of spatiotemporal profiles.