Influence of target material on structure of partly defocused laser beam pro duced plasma outflow

Our recent experimental results have proved that the formation of plasma jets is a fundamental process accompanying the laser produced plasma expansion, if a massive planar target with relatively high atomic number (Z) is irradiated by a defocused laser beam. It is impossible to get the plasma jet from light target material like Al or plastic. Experimental results presented here demonstrate differences in both the plasma configuration and the plasma source geometry between Cu (high-Z material) and plastic (low-Z material) targets. The experiment was carried out at the PALS iodine laser. An attempt of explanation of differences in the plasma configuration was taken by means of numerical simulations using the two-dimensional hydrodynamic code ATLANT-HE.