Dynamics of high-<i>Z</i>plasmas produced by a short-wavelength laser

Abstract

The dynamics and energy flow in Au plasmas produced by a 0.35-\ensuremath{\mu}m laser have been studied with layered targets with 6- and 24-beam spherical illumination from the Omega laser, to understand the processes leading to sub-keV x-ray emission. A significant enhancement in x-ray conversion at low intensities is observed for the 24-beam irradiations with higher energy, greater uniformity, and larger targets. Results are interpreted by comparison with hydrodynamics code calculations. The depth of energy penetration and x-ray emission in the plasma appears to be well understood, but some details of the x-ray time signatures and spectra are not.