Absorption of high-contrast 12-ps uv laser pulses by solid targets

The absorption of 12-ps prepulse free-laser pulses from a Raman amplified KrF laser has been measured at normal incidence for irradiances between 10¹⁴ and 10¹⁷ W cm^-2, and as a function of incident angle at 5×{}10¹⁶ W cm^-2, for both P and S polarizations. It is found that the main features of the experimental data are reasonably well modeled by a combination of resonance and collisional absorption, using a semianalytical treatment.