Studies on recombining Al-plasma using 1.06, 0.532, 0.355, and 0.266 μm laser radiation

We report studies on the emission spectra of Al-plasma produced by Nd:YAG laser and its harmonics. The electron temperature estimated using relative intensities of Al II lines is between 0.8 and 4.0 eV. The electron density measurement using Stark width broadened transition shows density of the order of 2×1016 cm−3. An estimate of plasma expansion velocity from temporal behavior at various distances from the target is also reported.