A Kirkpatrick-Baez Microscope for Core Implosion Imaging at NIF

ICF experiments have typical core diameters raging from $50\mu m$, in layered implosions, to $100\mu m$ in SymCaps. The emission spectrum is peaked between 8 and 10keV. Current X-ray imaging at NIF uses time resolved pinhole cameras with 10-20$\mu m$ pinholes that limit resolution and throughput to the detector. Selection of observed photon energy requires filtering that further reduces transmission. Low resolution, in combination with poor signal to noise ratio, limits the observable features during the later stages of capsule implosion. Using grazing incidence mirrors in a Kirkpatrick-Baez (KB) configuration, a focusing x-ray microscope is in design for NIF. The system will have x12 magnification, detector limited resolution and x10 higher throughput in comparison to pinhole systems. A KB microscope for imaging ICF experiments will be described, utilizing multilayer mirrors to enhance reflectivity for the core emission. Optimization of the multilayer coating allows observation of extended sources and high reflectivity in a selected energy band $>0.2$keV. Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-640864