Analytical study of the hydrodynamics of similarity flows from thin-foil laser plasmas

The hydrodynamic expansion of plasmas produced by laser beams focused on th in-foil tar gets is studied using a self-similar approach. The model is use ful for studying long-scale-length plasmas, produced by uniform laser irrad iation, which become fully underdense during the laser pulse. Bn essentiall y qualitative analysis of the hydrodynamics system in Cartesian geometry is given. In particular. a useful expression is obtained by integration of th e thermal energy equation.