A general purpose XUV laser spectrometer: some applications to N2, O2 and CO2

Coherent radiation is generated from 90 to 105 nm by frequency tripling the frequency-doubled output of a pulsed Nd: YG-pumped dye laser using a synchronized pulsed jet of various gases as the nonlinear medium. The XUV radiation is isolated by a pair of dichroic mirrors before interacting with a supersonically cooled gas target. Provisions have been made to measure the photoion yield as a function of wavelength using a time-of-flight mass spectrometer. In addition absorption by the target gas or fluorescence from the excited target and/or its fragments can be detected. Some applications are presented which illustrate the versatility of this XUV laser spectrometer involving 1+1 resonance-enhanced multiphoton ionization of N₂ and excitation of Rydberg states of O₂ and CO₂.