High-aspect-ratio laser-fusion targets driven by 24-beam uv laser radiation.

The compression of spherical, DT fuel pellets to high densities is achieved by depositing laser light on the surface of the target to create a high-temperature, ablating plasma. Many experimental and theoretical studies have established the advantages of short-wavelength laser irradiation for the effective coupling of laser energy into a high-density collisional plasmal-5 (without the generation of copious suprathermal electronss-6) and for the generation of high ablation pressures7 sufficient to drive an efficient compression on a low isentrope. From simple heuristic arguments,s and from the predictions of two-dimensional (2-D) hydrodynamic simulations,g implosion uniformity of spherical-shell targets to high final-core densities under direct multibeam laser irradiation will be maintained only for modest initial shell-aspect-ratios [(RIAR),] under a high degree of illumination uniformity.