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Koike, Masato; Ishino, Masahiko; Heimann, P. A.*; Imazono, Takashi; Takenaka, Hisataka*; Hatayama, Masatoshi*; Sasai, Hiroyuki*; Gullikson, E. M.*; Sano, Kazuo*
AIP Conference Proceedings 879, p.647 - 650, 2007/01
no abstracts in English
Imazono, Takashi; Koike, Masato
AIP Conference Proceedings 879, p.690 - 693, 2007/01
To develop a phase shifter made with a single-crystal functioning in an energy region between 0.7 keV and 1 keV and to characterize the state of polarization of polarized soft X-ray source using it, the polarization performance of natural muscovite mica single-crystal, KAl
(AlSi
O
)(OH), has been investigated using simulation calculation based on X-ray dynamical theory. The phase retardation of the transmitted light is found to increase with the crystal thickness. On the other hand, the average transmittance decreases with the thickness exponentially. When the crystal thickness is 3 
m, calculated phase retardations are 
at 
and 
at 
incidence, and the transmittance is 0.4%. These amounts are enough to characterize the state of polarization of the polarized light. Therefore it is concluded that muscovite crystal is an attractive material as a transmission-type phase shifter at 0.88 keV.
Okajima, Yuka; Matsumura, Daiju; Nishihata, Yasuo; Konishi, Hiroyuki; Mizuki, Junichiro
AIP Conference Proceedings 879, p.1234 - 1237, 2007/01
no abstracts in English
Shobu, Takahisa; Tozawa, Kazukiyo*; Shiwaku, Hideaki; Konishi, Hiroyuki; Inami, Toshiya; Harami, Taikan; Mizuki, Junichiro
AIP Conference Proceedings 879, p.902 - 906, 2007/01
BL22XU with undulator is consisted of one optical hutch and three experimental hutches and about 120m in length. The aim of this beamline is to perform diffraction and absorption experiment with anomalous dispersion, the high pressure experiments at high or low temperature with multi-anvil type and diamond-anvil type high pressure system and stress measurements. The energy region from 3 to 70keV and high flux of X-rays were required to satisfy these experimental conditions. Then we installed two kinds of monochromator by employing Si (111) crystals. One is SPring-8 "standard" double crystal monochromators to make low-energy X-rays from 3 to 37keV (L-mono), the other is double crystal monochromators, mechanically separated, but combined with calculation to make high-energy X-rays from 36 to 72keV (H-mono). These monochromators were arranged in the tandem for optics. L-mono can be used by lowering the first crystal of the H-mono, on the other hand the H-mono can be used by lifting the whole of L-mono. The liquid nitrogen is used for cooling the crystals, and as a result the high quality monochromatized X-rays is obtained. At the position of 115m from undulator, the beam size is 2.5 mm (vertical) 
3.5 mm (horizontal) (FWHM) and the flux is estimated to be 3 10
photon/s. But the stability of X-rays is rather poor because of the vibration caused by nitrogen liquid cooling system. The vertical position of X-rays changes by about 0.2 mm in a few minutes of periods, and the intensity of X-rays varies at about 10%. The stable X-rays within a limitation of accuracy can be obtained by using Monochromator stabilization, so called MOSTAB, which is a feedback control system.
Shobu, Takahisa; Kaneko, Hiroshi; Mizuki, Junichiro; Konishi, Hiroyuki; Shibano, Junichi*; Hirata, Tomoyuki*; Suzuki, Kenji*
AIP Conference Proceedings 879, p.1581 - 1585, 2007/01
The third generation synchrotron X-ray source such as SPring-8 provides us intense beams of high energy X-rays. The techniques of non-destructive internal residual stress measurement for industrial applications are well established by angle dispersive diffractometry with high energy synchrotron radiation and provide valuable information. The energy dispersive diffraction techniques using white radiation is the advantage of a stress measurement compared with the angular dispersive one. For example, the multitudes of reflections recorded in one spectrum offers additional information that can be used for stress gradient evaluation. The purpose of present study is to apply high energy white X-rays to the measurement of the residual strain in the bulk specimen. The experiment was carried out on the beamline BL14B1 at SPring-8. A diffraction pattern was collected by a Ge Solid State Detector (SSD) mounted on the arm of a 2-axes diffractometer behind two sets of secondary collimating slits. The beam size of white X-rays was 0.05 0.3 mm
. The specimens were JIS-S45C carbon steel and JIS-SUS304 austenitic stainless steel with a thickness of 5mm. The bending stress was applied with the four-point bending and the strain at the surface of the specimen was measured by a strain gauge as shown in the figure. X-rays diffraction measurement was carried out simultaneously. The figure shows each diffraction profile of SUS304 taken with white X-rays. The strain was calculated by the ratio of the energy shift to the peak energy. Though many peaks appeared in every measured positions Y, each diffraction pattern depended on the number and the orientation of crystal grains in irradiated volume by X-rays. The calculated strain by using a single peak is depending on peak quality. The accurate internal stress can be obtained with white X-rays by selecting the peak at high energy, high peak counts and close to Gaussian peak profile.
Kiriyama, Koji; Shiwaku, Hideaki; Mochizuki, Tetsuro*; Shobu, Takahisa; Tozawa, Kazukiyo*
no journal, ,
Oscillating inhibition methods for mechanical vibrations on the cryogenically-cooled Si monochromator have been developed on BL11XU at SPring-8. The intensity fluctuation of the X-rays of the monochromator was observed. So, we need to identify the vibration sources and take countermeasures against the vibrations to keep quality of X-rays. In this study, the intensity fluctuation of the X-rays, vibrations larger than 1 Hz on the X-rays and the crystals was measured thoroughly. Without the oscillating inhibition methods, observed intensity fluctuation of X-rays was irregular in several minutes and uneven every second. Measured vibration frequencies were mainly 1
10 Hz, 20 Hz, 55 Hz on X-rays, and were mainly 110 Hz, 30 Hz, and 50 Hz on crystals. The countermeasures were found to be dramatically effective to restrain on the vibrations. As a result, the width of the intensity fluctuation with time decreased from 2.86 percent to 1.46 percent (std. deviation: 0.008302 to 0.004479) that means improving the stability of X-rays from monochromator. The oscillating inhibition methods in the present study on BL11XU at SPring-8 can be applied to the similar monochromator at the other beamlines.
