Laser-driven hydrothermal wave speed in low-Z foam of overcritical density

The speed of the laser-supported hydrothermal wave is experimentally measured in porous polystyrene with overcritical average density. The results of the experiments are in agreement with the simulations performed with the MULTI-FM code, modeling the state of partly homogenized plasma. The measured velocity is 2 times smaller than the shock wave velocity calculated in simulations under the same conditions of laser irradiation in a homogeneous substance of the same density. The obtained results allow us to better investigate the possibility of using porous matter of overcritical density as an effective absorber-ablator in laser thermonuclear fusion targets. Published by AIP Publishing.