Spatial and Temporal Evolution of Laser-Generated Plasmas Measured Through Langmuir Probe

The space and time evolution of the electron density n(e) and electron temperature T-e have been measured using a Langmuir probe (LP) immersed into a pulsed Nd:YAG laser-generated plasma. The measurements have been performed in vacuum at different distances from the target surface and along its normal direction. The plasma density and temperature decrease exponentially with the distance from the target and with the time as from the laser pulse and expand at supersonic velocity in vacuum. LP permits to characterize the plasma giving information on the charge particle kinetics.