STUDIES ON LASER-DRIVEN SHOCKS USING A ND-GLASS LASER

A review of work done on laser generated shocks in solids using a high -peak-power Nd:glass laser in the Laser and Plasma Technology Division of the Bhabha Atomic Research Centre is presented in this paper. The 20-J/5-ns Nd:glass laser used in the experiments is able to produce fo cused laser intensities in the range of 5 x 10(11)-10(13) W/cm(2) and a shock pressure in the range of 0.1-5 Mbar. A 1-J/100-ps Nd:glass las er is also being developed for laser shock studies, details of which a re presented. Several diagnostics have been developed for laser shock studies of which the main diagnostics are optical shadowgraphy, optica l interferometry, and laser velocity interferometry for particle veloc ity measurement. The measurement of ablation pressure in various types of targets, the scaling of ablation pressure with laser intensity, th e effect of laser beam nonuniformity on shockfront or ablation pressur e uniformity, the smoothing of shockfront and pressure profiles in hig h-Z coated and high-Z doped targets, and so on, are the various experi mental studies conducted. We have tried to study X-ray driven ablation in aluminum and plastic targets using gold and copper as X-ray produc ing targets. Uniform pressure of about 0.1 Mbar has been generated ove r an area of 4 mm(2).