Investigation of Weakly Ionized Plasma Channel by Accumulation Effect of Charged Particles Using High Repetition Rate KrF Excimer Laser

A weakly ionized plasma channel produced by an ultra-violet laser was adopted for laser triggered lightning method. It is excellent for guiding ability because of expecting a long plasma channel. Triggering ability, however, is not expected so much because of being low plasma density. So, it is studied to improve the triggering ability using a kHz high repetition rate of KrF excimer laser. Using this type of laser it is so expected of the accumulation effect caused by charged particles that the plasma density can be enhanced and it connects to improve triggering ability. Moreover, up to the present, the studies of laser-triggered lightning with kHz high repetition rate have not been reported. The density of charged particles produced by this type of laser was measured. From this experiment, the accumulation effect of charged particles and enhanced triggered discharge were confirmed in the case of laser repetition rate of 1 kHz.