The interaction of 1.06 μm laser radiation with high Z disk targets

Gold disks have been irradiated with 1.06 μm laser light at intensities between 7 × 1013 and 3 × 1015 W/cm2, and pulse lengths between 200 and 1000 psec. Due to the high Z and long pulse, inverse bremsstrahlung becomes an important absorption mechanism and competes strongly with resonance absorption and stimulated scattering. In addition to measured absorptions, data on the temporal, spatial, angular, and spectral characteristics of the x‐ray emission are presented. Temporally and spectrally resolved back‐reflected light, and polarization‐dependent sidescattered light are detected, providing estimates for the amount of stimulated scattering and of the coronal electron temperature. Inhibited electron thermal conduction and nonlocal thermodynamic equilibrium ionization physics play key roles in bringing numerical simulations of these experiments into agreement with all of the above‐mentioned data.

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