Kinetic studies following state selective laser excitations

State-selective inelastic and reactive collisions of xenon atoms and eximers were studied. The reactants are excited by multiphoton laser absorption while product channels are observed by their fluorescence. For any mixture of gases, the reactants which can be studied by obtaining excitation spectra are determined, where the intensity of laser induced fluorescence is measured as a function of laser frequency. The product energy disposal in product channels was determined by measuring the fluorescence spectra at fixed laser frequencies which excite reactants. State-to-state reaction rates are measured for the reactants by observing the time dependence of the fluorescence of both the reactants and products following excitation by the laser. The experiments are similar and complimentary to those using synchrotron radiation. For excited state energies up to 15 eV, multiphoton excitation offers the advantages of better time and energy resolution, a greater choice of excited state multiplicity, and a significant longer absorption length.