Development of holographic methods for investigating a moving free surface, accelerated by laser-induced shock waves

Holographic methods developed to study the behavior of surfaces shocked by high power lasers are reported. Shock waves of the order of hundreds of kil obars are generated in Sn targets 50-mu m thick, by a Nd:YAG laser system w ith a wavelength of 1.06 mu m, a pulse duration of 7.5 ns FWHM, and irradia nce in the range (1.0-2.6) 10(13) W/cm(2). Two configurations of off-axis h olography were applied: holograms based on forward scattering, and hologram s of both backward and forward scattering. The hologram is produced by scat tering of a pulse, 6.7 ns (FWHM), of green laser light synchronized with th e laser that generates the shock wave. Holograms of the topology of the rea r surface of shocked Sn targets moving in vacuum and in air (at atmospheric pressure) are reported.