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Imazono, Takashi; Koike, Masato; Hasegawa, Noboru; Koeda, Masaru*; Nagano, Tetsuya*; Sasai, Hiroyuki*; Oue, Yuki*; Yonezawa, Zeno*; Kuramoto, Satoshi*; Terauchi, Masami*; et al.
Journal of Physics; Conference Series, 425(15), p.152008_1 - 152008_4, 2013/03
Times Cited Count:3 Percentile:80.25We have developed a flat-field spectrograph equipped with a wide-band multilayer grating and prefocusing mirror for the 2-4 keV range. To realize a spectrograph without any mechanical movement, the multilayer has a newly invented layer structure to uniformly enhance the diffraction efficiency (or reflectivity) of the grating (or prefocusing mirror) at a fixed angle of incidence in the whole energy region. The multilayer structure consisting of W and BC layers has been deposited by ion beam sputtering method on a varied-line-spacing laminar-type holographic grating. Also the same multilayer has been done on a spherical substrate. The average diffraction efficiency (or reflectivity) of the multilayer grating (or spherical mirror) is in excess of 3% at 88.65
(or 4% at 88.00
) in the 2.1-3.8 keV range. The throughput of the spectrograph with multilayer optics can be evaluated to be 2-5000 times higher than that with conventional optics coated by a gold layer.
Hu, W.; Takahashi, Masamitsu; Kozu, Miwa*; Nakata, Yuka*
Journal of Physics; Conference Series, 425(20), p.202010_1 - 202010_4, 2013/03
Times Cited Count:1 Percentile:53.89Inami, Toshiya; Michimura, Shinji*; Matsumura, Takeshi*
Journal of Physics; Conference Series, 425(13), p.132011_1 - 132011_5, 2013/03
Times Cited Count:6 Percentile:90.82Resonant X-ray diffraction is a powerful tool for detecting ordered structures of charge, magnetic and orbital degrees of freedom. The symmetry of an order parameter is determined by changing the relative orientation between the polarization of incident X-rays and the order parameter. A new method suited for extreme conditions is performed by rotating the incident polarization using a diamond phase plate. A disadvantage of this method is significant loss in intensity for low-energy X-rays. In order to obtain both a high degree of linear polarization and strong X-ray intensity, we have constructed optics that compensates chromatic aberration using two diamond phase plates. In a test experiment in beamline BL22XU at SPring-8, two 300 microns diamond phase plates were used. The obtained linear polarization reached more than 96% at 6.15 keV, showing marked improvement compared to the linear polarization 90% obtained by a single 500 microns phase plate.