Gigabar shock wave driven by laser-accelerated electron stream

Abstract

Abstract Theoretical and computational results for the generation of a powerful shock wave with pressure behind the front exceeding a gigabar level in the half-space of a solid when the boundary layer is heated by a flux of laser-accelerated electrons are presented. The influence of the energy flux density of the heating stream, the characteristic initial energy and the electron spectrum on the characteristics of the shock wave is investigated. The main attention is paid to the generation of an extremely powerful shockwave, which can be applied in experiments to study the equation of state of matter. For this, the requirements for the parameters of a laser pulse that can ensure the propagation of a plane shock wave with a gigabar pressure when a substance is heated by a beam of laser-accelerated fast electrons, taking into account its divergence, are established. It is shown that one of the features of the propagation of a shock wave under the impact of a thermal piston heated by fast electrons consists in the radiation cooling of the peripheral region of the substance covered by the shock wave. An increase in the compression of matter due to radiation cooling leads to a multiple increase in the density of matter in the peripheral region of the shock wave compared to the density at its front. The final result of this work is to substantiate the use of shock waves driven by a beam of laser-accelerated electrons in a laboratory experiment to study the properties of matter, in particular, metals compressed to a density of several tens of g cc−1 under the action of gigabar pressure.