Interactions of the laser beam of iodine laser 'PALS' with low-density foam targets and acceleration of Al foils by the pressure of heated foam matter are investigated here, both experimentally and theoretically. An x-ray streak camera was used for the evaluation of the speed of energy transfer through the porous foam material. X-ray streak records show no noticeable emission near the Al foil at the rear side of a 400 µm thick foam and, thus, Al foil is most likely accelerated without significant heating and expansion. Accelerated foil velocities, measured by three-frame optical shadowgraphy, reach up to 107 cm s−1. Experimental results compare well with our two-dimensional hydrodynamics simulations and with an approximate analytical model.
Shock impedance matching experiments in foam - solid targets: implications for `foam-buffered ICF'