Ultra-intense laser-plasma interaction toward Weibel-mediated collisionless shocks formation

The rapid developments in laser technology will soon offer the opportunity to study in the laboratory the processes driving Weibel-mediated collisionless shocks, typical of various astrophysical scenarii. The interaction of an ultra-intense laser with an overdense plasma has been identified as the preferential configuration. Yet, the experimental requirements still need to be properly investigated. High performance computing simulations are a necessary tool for this study. In this work, we present a series of kinetic simulations performed with the PIC code \underline {SMILEI}, varying the laser and plasma parameters.~ In particular, we will study the effect of the laser polarisation and plasma density to obtain the best conditions for the creation of a collisionless shock. The role of the electrons heated at the interaction surface and of particles accelerated~ via the Hole Boring (laser-piston) mechanism on the generation of the current filamentation~ instability and the subsequent shock front formation will be highlighted.