Soft recovery technique to investigate dynamic fragmentation of laser shock-loaded metals

With the development of high energy laser facilities dedicated to inertial confinement fusion, the question of debris ejection from metallic shells subjected to intense laser irradiation has become a key issue. We have used two diagnostics to investigate fragmentation processes. Recovery of ejected fragments has been performed in a highly transparent gel of density 0.9 g/cm(3). Fragments sizes, shapes, and penetration depths, can be easily observed with a spatial resolution of micrometer-order. Complementary data are provided by transverse shadowgraphy which allows to obtain quasi-instantaneous, successive pictures of the debris clouds and mean ejection velocities.