title: Kirkpatrick-Baez microscope for hard X-ray imaging of fast ignition experiments.
abstract: A Kirkpatrick-Baez X-ray microscope has been developed for use on the Titan laser facility at the Lawrence Livermore National Laboratory in Fast Ignition experiments. It was developed as a broadband alternative to narrow band Bragg crystal imagers for imaging Kα emission from tracer layers. A re-entrant design is employed which allows for alignment from outside the chamber. The mirrors are coated with Pt and operate at a grazing incident angle of 0.5° providing higher resolution than an equal brightness pinhole and sufficient bandwidth to image thermally shifted characteristic Kα emission from heated Cu tracer layers in Fast Ignition experiments. The superpolished substrates (<1 Å rms roughness) had a final visible wavelength roughness of 1.7 Å after coating, and exhibited a reflectivity corresponding to an X-ray wavelength roughness of 7 ± 1 Å. A unique feature of this design is that during experiments, the unfiltered direct signal along with the one-dimensional reflections are retained on the detector in order to enable a live indication of alignment and incident angle. The broad spectral window from 4 to 9 keV enables simultaneous observation of emission from several spectral regions of interest, which has been demonstrated to be particularly useful for cone-wire targets. An experimentally measured resolution of 15 μm has been obtained at the center of the field of view.
authors: University of Alberta, 116 St. and 85 Ave., Edmonton, Alberta T6G 2R3, Canada. hal@ualberta.ca
authors: H
authors: H
authors: Friesen
authors: H F
authors: HF
authors: Tiedje
authors: D S
authors: DS
authors: Hey
authors: M Z
authors: MZ
authors: Mo
authors: A
authors: A
authors: Beaudry
authors: R
authors: R
authors: Fedosejevs
authors: Y Y
authors: YY
authors: Tsui
authors: A
authors: A
authors: Mackinnon
authors: H S
authors: HS
authors: McLean
authors: P K
authors: PK
authors: Patel