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Soutome K.,Japan Synchrotron Radiation Research Institute | Soutome K.,RIKEN | Kaneki K.,SPring 8 Service Co. | Shimosaki Y.,Japan Synchrotron Radiation Research Institute | And 2 more authors.
IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference | Year: 2016

A lattice of a newly designed 6GeV electron storage ring for the SPring-8 upgrade project is of a 5-bend achromat type. The betatron phase between the two dispersion arcs is set to (2n+1)π to suppress harmful effects of chromaticitycorrecting sextupoles, By detuning this phase, optimizing sextupole strengths in a cell and introducing octupoles, we can obtain a sufficient dynamic aperture for beam injection even for the symmetry-broken ring having four long straight sections and a high-beta injection section. However, the off-momentum behavior such as the non-linear chromaticity needs to be optimized to achieve a target momentum acceptance of 3% or larger. We hence extended the excitation pattern of sextupoles from one unit cell to plural cells to increase the number of tuning knobs. By this scheme we succeeded in suppressing the lowest order coefficients of amplitude-dependent tune shift and the second order chromaticities at the same time. Results of the optimization will be presented together with a problem still remained. Copyright © 2016 CC-BY-3.0 and by the respective authors.


Oji H.,Japan Synchrotron Radiation Research Institute | Oji H.,SPring 8 Service Co. | Matsumoto T.,Japan Synchrotron Radiation Research Institute | Matsumoto T.,SPring 8 Service Co. | And 3 more authors.
Journal of Physics: Conference Series | Year: 2014

We have developed a noble HAXPES measurement system, where the controls for sample manipulation and VG Scienta R4000 work together. The main part of the system is developed by spec. R4000 is controlled by sending commands from spec to the TCP server programed by LabVIEW with SESWrapper library. The command line interface of spec is wrapped by a graphical user interface (GUI) which can be easily operated by users. The sample can be aligned in the intuitive way by clicking the position to be measured on the sample image. Fine alignment can be done by scanning the sample position to maximize the count rate of photoelectrons. After setting measurement positions and conditions on the GUI, the automatic measurements through the multiple measurement positions can be performed in this system.


Cui Y.-T.,Japan Synchrotron Radiation Research Institute | Li G.-L.,Henan University of Science and Technology | Oji H.,Japan Synchrotron Radiation Research Institute | Oji H.,SPring 8 Service Co. | And 2 more authors.
Journal of Physics: Conference Series | Year: 2014

The core level and valence band spectra of group IVA elements were investigated with hard x-ray photoemission spectroscopy (HAXPES) photon energy of 7.939 keV by bulk sensitive manner. The survey and valance band spectra were presented, relative peaks intensity are discussed by thinking about inelastic mean free path (IMFP) and photoionization cross section of photoelectrons (PICS). In order to understand bulk band structures, valence bands are compared with the calculated ones by considering PICS, IMFP and total energy resolution. The calculated results by GGA, HSE06 and GW0 methods are simply discussed by comparing with experiment spectra.


Fukuhara M.,Tohoku University | Fujima N.,University of Shizuoka | Oji H.,Japan Synchrotron Radiation Research Institute | Oji H.,SPring 8 Service Co. | And 2 more authors.
Journal of Alloys and Compounds | Year: 2010

To elucidate the hydrogen localization sites in the atomic clusters of Ni-Nb-Zr-H glassy alloys exhibiting room-temperature Coulomb oscillation, we investigated the effect of hydrogen on the electronic state of the elements forming the glassy alloys, as well as the coordinating position of the hydrogen atoms, by X-ray absorption fine structure (XAFS) analysis, referencing theoretical simulation results. The XANES (X-ray absorption near edge structure) part of the XAFS spectra for each (Ni, Zr and Nb) K-edge of (Ni0.36Nb0.24Zr0.40)89H11 shows clear multiple scattering effects caused by charged hydrogen atoms. The distorted Ni5Zr5Nb3 cluster with the maximum size of 0.55 nm is characterized by five Ni atoms constituting half a pentahedron and an opposite pentahedral Zr-Nb assembly. For the hydrogen localization sites, the first-principles calculations show that there are two Zr-Zr-Nb-Nb, four Zr-Zr-Zr-Nb, two Zr-Zr-Nb-Ni and two Zr-Zr-Zr-Ni tetrahedrons, in the order of stability. © 2010 Elsevier B.V. All rights reserved.


Belik A.A.,Japan International Center for Materials Nanoarchitectonics | Matsushita Y.,SPring 8 Office | Katsuya Y.,SPring 8 Service Co. | Tanaka M.,SPring 8 Office | And 3 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

The 6H-SrMnO3 polymorph was prepared using a high-pressure and high-temperature technique at 6 GPa and 1773 K. Its crystal structure was refined using synchrotron x-ray powder diffraction data (space group P6 3/mmc (no. 194), Z = 6, a = 5.42892(1) Å, c = 13.40252(3) Å). Magnetic and transport properties of 6H-SrMnO3 were investigated using direct current magnetization, specific heat, and resistivity measurements. The antiferromagnetic Néel temperature TN of 6H-SrMnO3 is 235 K; this value is close to that of cubic-SrMnO 3 (TN = 240 K) and 4H-SrMnO3 (TN = 280 K). 6H-SrMnO3 and 4H-SrMnO3 have the same building blocks of face-sharing MnO6 octahedra. Magnetic susceptibility of 6H-SrMnO3 exhibits behavior typical for classical three-dimensional antiferromagnets with a maximum near TN-in contrast to those of cubic-SrMnO3 and 4H-SrMnO3, where broad maxima are observed far above TN. Isothermal magnetization curves of 6H-SrMnO3 (at 2 K) show an upturn deviation from the linear behavior above 10 kOe, indicating a possible spin-flop magnetic phase transition. © 2011 American Physical Society.


Matsumura D.,Japan Atomic Energy Agency | Okajima Y.,SPring 8 Service Co. | Nishihata Y.,Japan Atomic Energy Agency
Journal of Physics: Conference Series | Year: 2016

We have studied surface structural change of supported Pd metal nanoparticles caused by CO adsorption and following temperature increase by using in situ and time-resolved X- ray absorption fine structure technique with dispersive optics. CO adsorption on Pd metal nanoparticles at room temperature shows two types of adsorption behavior and the less stable CO which brings about surface expansion of Pd metal nanoparticles is desorbed just after temperature increase. Pd carbide layer is created at around 350 °C by CO decomposition, which was clearly detected by the elongation of Pd-Pd interatomic distance and the increase of Debye-Waller factor and third cumulant.


Sun H.-T.,International Center for Young Scientists | Matsushita Y.,BL15XU | Sakka Y.,Japan National Institute of Materials Science | Shirahata N.,Japan National Institute of Materials Science | And 5 more authors.
Journal of the American Chemical Society | Year: 2012

For the first time, direct experimental evidence of the formation of monovalent Bi (i.e., Bi+) in zeolite Y is provided based on the analysis of high-resolution synchrotron powder X-ray diffraction data. Photoluminescence results as well as quantum chemistry calculations suggest that the substructures of Bi+ in the sodalite cages contribute to the ultrabroad near-infrared emission. These results not only enrich the well-established spectrum of optically active zeolites and deepen the understanding of bismuth related photophysical behaviors, but also may raise new possibilities for the design and synthesis of novel hybrid nanoporous photonic materials activated by other heavier p-block elements. © 2012 American Chemical Society.


Schnepp Z.,Japan National Institute of Materials Science | Hollamby M.J.,Japan National Institute of Materials Science | Tanaka M.,Station X | Matsushita Y.,Station X | And 2 more authors.
Science and Technology of Advanced Materials | Year: 2012

Metal oxide/nitride nanocomposites have many existing and potential applications, e.g. in energy conversion or ammonia synthesis. Here, a hybrid oxide/nitride nanocomposite (anatase/Ti xW 1xN) was synthesized by an ammonia-free sol-gel route. Synchrotron x-ray diffraction, complemented with electron microscopy and thermogravimetric analysis, was used to study the structure, composition and mechanism of formation of the nanocomposite. The nanocomposite contained nanoparticles (<5nm diameter) of two highly intermixed phases. This was found to arise from controlled nucleation and growth of a single oxide intermediate from the gel precursor, followed by phase separation and in situ selective carbothermal nitridation. Depending on the preparation conditions, the composition varied from anatase/Ti xW 1xN at low W content to an isostructural mixture of Ti-rich and W-rich Ti xW 1xN at high W content. In situ selective carbothermal nitridation offers a facile route to the synthesis of nitride-oxide nanocomposites. This conceptually new approach is a significant advance from previous methods, which generally require ammonolysis of a pre-synthesized oxide. © 2012 National Institute for Materials Science.


Kagoshima Y.,University of Hyogo | Takano H.,University of Hyogo | Takeda S.,SPring 8 Service Co.
Applied Physics Letters | Year: 2012

An inclined-incidence quasi-Fresnel lens made of acrylic resin has been developed for prefocusing in synchrotron radiation x-ray beamlines. By inclining the lens, the grating aspect ratio is large enough for x-ray use. As it operates in transmission mode with negligible beam deflection and offset, little additional equipment is needed to introduce it into existing beamlines. It is fabricated by sheet-press forming, enabling inexpensive mass production. The prototype was able to focus a 730-μm-wide beam to a width of 80 μm with a photon flux density gain of 5.6 at an x-ray energy of 10 keV. © 2012 American Institute of Physics.


Ueda S.,Japan National Institute of Materials Science | Katsuya Y.,SPring 8 Service Co. | Tanaka M.,Japan National Institute of Materials Science | Yoshikawa H.,Japan National Institute of Materials Science | And 4 more authors.
AIP Conference Proceedings | Year: 2010

The revolver undulator beamline BL15XU at SPring-8, which is the contract beamline of National Institute for Materials Science (NIMS), was established for materials science using soft-and-hard X-ray photoelectron spectroscopy (XPS) and high-resolution powder X-ray diffraction (XRD). We have performed beamline reconstruction for further developments of the experiments in the research field of materials science. The flat double-crystal monochromator (DCM) with liquid nitrogen cooling, X-ray total reflection double-mirror system with (+,-) geometry, and high-energy-resolution channel-cut monochromator have been installed into the beamline. The refined beamline provides monochromatic X-rays from 2 to 36 keV. The improvement of the photon flux density at the XRD and XPS experimental stations was confirmed. The photon flux was estimated to be several 1012photons/sec with ΔE/E of ∼10-4. © 2010 American Institute of Physics.

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