X-ray crystal imagers for inertial confinement fusion experiments (invited)

We report on our continued development of high resolution monochromatic x-r ay imaging system based on spherically curved crystals. This system can be extensively used in the relevant experiments of the inertial confinement fu sion (ICF) program. The system is currently used, but not limited to diagno stics of the targets ablatively accelerated by the Nike KrF laser. A spheri cally curved quartz crystal (2d=6.687 03 Angstrom, R=200 mm) has been used to produce monochromatic backlit images with the He-like Si resonance line (1865 eV) as the source of radiation. Another quartz crystal (2d=8.5099 Ang strom, R=200 mm) with the H-like Mg resonance line (1473 eV) has been used for backlit imaging with higher contrast. The spatial resolution of the x-r ay optical system is 1.7 mu m in selected places and 2-3 mu m over a larger area. A second crystal with a separate backlighter was added to the imagin g system. This makes it possible to make use of all four strips of the fram ing camera. Time resolved, 20X magnified, backlit monochromatic images of C H planar targets driven by the Nike facility have been obtained with spatia l resolution of 2.5 mu m in selected places and 5 mu m over the focal spot of the Nike laser. We are exploring the enhancement of this technique to th e higher and lower backlighter energies. (C) 1999 American Institute of Phy sics. [S0034-6748(99)73601-4].