High-Brightness $\sim $keV Source and Diagnostic Development

High-energy-petawatt (HEPW), laser-driven backlighter sources with photon energies from $\sim $1 to $\sim $ 3 keV have a broad range of applications in high-energy-density physics and inertial confinement fusion. Backlighter source development studies have been performed on the VULCAN petawatt laser at RAL and the Multi-Terawatt laser at LLE and will be continued on OMEGA EP. The x-ray emission was measured on aluminum flat-foil targets. A conversion efficiency of up to 1 $\times $ 10$^{-5}$ 1/eV/sr from laser energy into the Al He$_{\alpha }$-line energy was observed. Assuming a circular emission region with a FWHM of $\sim $25 \textit{$\mu $}m and an emission time of 30 ps a brilliance of $\sim $15 J/eV/ps/sr/cm$^{2}$ can be inferred. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement DE-FC52-92SF19460.