Laser induced fluorescence spectroscopy in flames

The use of laser induced fluorescence spectroscopy (LIF) is described for making measurements in the combustion environment. Some background in molecular structure, spectroscopic concepts, thermodynamics and combustion chemistry is first presented. This is followed by application of the rate equations to model and demonstrate the response of atomic and molecular systems to laser excitation. Next, experimental aspects are explored, including excitation, optical signal collection, dispersion and detection, signal conditioning, uncertainty and detectability, recovering population distributions from spectra, and sources of systematic error. Finally, specific strategies for measuring concentration, temperature, pressure and velocity are discussed. An example of selecting a collisional rate set for modeling purposes is given in an Appendix.