Perturbation transfer from the front to rear surface of laser-irradiated targets.

We present experimental results on the perturbation transfer of laser irradiated planar foils. Perturbed polystyrene foils were irradiated directly by laser at intensity of $6\ifmmode\times\else\texttimes\fi{}{10}^{13} \mathrm{W}/{\mathrm{cm}}^{2}.$ We measured perturbations on the foils by side-on x-ray backlighting technique. Perturbations on the rear surface due to the rippled shock front were observed just after the shock breakout. We also observed feedthrough of perturbations on the laser-irradiated surface that grows due to the Rayleigh-Taylor instability.