Laser-induced ionization of air in the presence of preionization

Ionization of air at different pressures is studied for the following situations: (1) a spark gap acting as a preionizer alone, (2) a preionizer with a pulsed CO/sub 2/ laser, (3) a preionizer with a CW CO/sub 2/ laser, (4) a preionizer with a Q-switched Nd:YAG laser, and (5) and a Nd:YAG laser with a CO/sub 2/ laser. Results are quantified and analyzed with respect to some available data.<
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