Laser prepulse effect on thermal smoothing of non-uniformities
of target illumination is studied by means of 2D Lagrangian
hydrodynamics simulation, based on parameters of real experiment.
A substantial smoothing effect is demonstrated in case
of an optimum delay between the prepulse and main heating
laser pulse. The cause of enhancement of thermal smoothing
effect by laser prepulse is the formation of long hot layer
between the region of laser absorption and ablation surface.
Comparison with experimental results is presented.