Investigation of the Feasibility of Using Laser Induced Fluorescence for Concentration Measurements by Diatomic Sulfur

摘要

The feasibility of using laser induced fluorescence to measure total S2 number densities in a laboratory environment is studied. A rate equation analysis modeling transitions within the B to the 3rd power negative summation u-to the 3rd power negative summation g system of S2 is developed and applied to model the frequency prime = 9, frequency double prime = 6 transition at 3214.6 angstroms. Excitation spectra were obtained over the range of 2890 to 2810 angstroms clearly showing the frequency double prime = 0, frequency prime = 8 and frequency double prime = 0, frequency prime = 9 absorption bands. Fluorescence scans of the frequency prime = 8, frequency double prime = 1 through 24 and frequency prime = 9, frequency double prime = 1 through 25 were taken. After these broad spectra were identified, further investigations of the frequency prime = 9, frequency double prime = 6 transition included fluorescence intensity versus temperature, laser power, and pressure. Additional measurements of quenching, radiative lifetime and self absorption are made.