Study of the Preplasma Generation for Flat and Nanostructured Targets in Case of Oblique Radiation Incidence

In this proceeding, we compare the preplasma generation in front of the flat and nanostructured targets for different angles of laser incidence. We use radiation-hydrodynamic FLASH code to simulate the laser prepulse interaction with aluminum foil and aluminum nanowire array with aluminum support. During the preplasma evolution, we observe the following stages: heating of the target, generation of preplasma cloud, nanowire implosion and the increase of preplasma density in front of the target, generation of the overcritical-density regions in front of the regions, and joining of the overcritical density regions into a continuous overcritical density layer. The rate of preplasma generation varies in function of the tilting angle. For small tilting angles it decreases with its variation. The rate of preplasma generation is minimal for the tilting angle of about 15 degrees. For lower and higher values of the tilting angle, the preplasma generation ratio is greater. Back-reflection for the nanostructured targets is lower than for the flat target. Its value also depends on the angle of laser incidence. This aspect can potentially increase the safety and the performance of the experiments.