Spatial distribution of dynamic mechanical stresses in ionic crystals under the action of a pulsed electron beam

We report on the results of experimental and theoretical investigation of the shape of an acoustic pulse generated in alkali-halide crystals by a pulsed electron beam with a maximal electron energy of 0.28 MeV and an energy density of 0.10–0.65 J/cm$^2$. It is found that the shape of the acoustic pulse for the given beam parameters substantially differs from the absorbed energy density profile. The formation of the fine structure of the acoustic pulse is associated with local release of energy due to the evolution of multichannel electrical breakdown.