Parametric study of the current induced in a CO2 laser plasma

The current generated during the interaction of a focused 10.6‐μm CO2 nanosecond laser pulse with a copper target was measured as a function of laser power—up to 2.5 GW—and of the background nitrogen pressure from 10−5 to 103 Torr. Current distribution at the target was measured. The results show a resonance effect at 10−2 Torr with a total current flow of 250 kA.