Progress in zirconium resonance ionization spectroscopy

We have examined the stepwise-resonant three-photon-ionization spectrum of neutral Zirconium atoms using three separately-tunable pulsed visible dye lasers. The ground-level (first-step) transitions were chosen on the basis of demonstrated 91Zr selectivity. Lifetimes of even-parity levels around 36000 cm-1, measured with the delayed- photoionization technique, range from 10 to 100 nsec. Direct ionization cross sections appear to be less than 10-17 cm2; newly-detected autoionizing levels give peak ionization cross sections (inferred from saturation fluences) up to 10-15 cm2. Portions of Rydberg series converging to the 315 and 763 cm-1 levels of Zr+ were identified. 'Clumps' of autoionizing levels are thought to be due to Rydberg-valence mixing.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.