bluuebunny/crossref_metadata_2025 huggingface dataset:
High-energy magnetic Compton scattering experiments at ESRF
Authors: Tschentscher Th. , McCarthy J. E. , Honkimäki V. , Suortti P.
Published: July 2004

Investigations of spin densities in ferromagnetic materials using magnetic Compton scattering are reported. At the high-energy beamline ID15 at the ESRF, experiments have been carried out utilizing the high flux at very high photon energies. Energies from 60 up to 1000 keV have been used for investigations of experimental resolution, cross section, spin moments and momentum distribution. Optimized conditions are found for photon energies from 200 to 250 keV with a momentum resolution < 0.4 a.u. and a doubled magnetic effect compared with earlier measurements. In the determination of absolute spin moments multiple scattering has to be taken into account.
Rapid projection of crystal grain orientation distribution in aluminium alloy sheets by synchrotron X-ray diffraction
Authors: Kawasaki K. , Koizumi M. , Inagaki H.
Published: July 2004

An investigation of the primary recrystallization and the grain growth process of aluminium alloy sheets has been carried out using a method for rapid projection of the crystal grain orientation distribution. It is found that the projected pattern is continuous in the cold-rolled state. When the sheet is annealed, tiny diffraction spots or small grains appear. The addition of Mg greatly alters the sizes and number of grains, and the orientation of the grains in sheets.
A beamline for photochemical processes at atmospheric pressure
Authors: Takahashi Jun-ichi , Utsumi Yuichi , Hosokawa Teruo , Ushiki Jun , Tadano Toshiaki
Published: July 2004

A beamline especially designed for atmospheric photochemical reactions has been constructed at the NTT synchrotron radiation facility. By inserting a buffer helium chamber with Be and Si3N4 partition windows between the beamline and the reaction chamber, studies can be performed without the differential pumping systems normally used in existing photochemistry beamlines. The reaction chamber is equipped with a gas supply system and analysis systems to investigate gas-phase and surface reactions. Purging using dry purified gases in combination with water-bubbling gives effective control of water concentration in the reaction chamber.
XAFS spectra from reflectivity measurements
Authors: Tani Katsuhiko , Nanjyo Takeshi , Masui Shin , Saisho Hideo
Published: July 2004

The reflectivity of TiSi2 films was measured as a function of photon energy E at the Ti K-edge region at a glancing angle θ close to the critical angle θ
C
of total reflection. TiSi2 silicide films (about 30 nm thickness) were prepared by silicidation of Ti thin films deposited on Si(001) substrates. Since the Fresnel reflectivity R(θ,E) is a function of the dispersion δ(E) and of the absorption β(E), the absorption β(E) which carries the XAFS signal can be solved as β(θ,δ,R) for observed reflectivity R and for estimated δ. The dispersion δ(E) is related to the absorption β(E) by the Kramers–Kronig (K–K) relations since the refractive index is n(E) = 1 − δ(E) − iβ(E). β(E) was calculated from the observed reflectivity R(θ,E) using theoretical values for initial δ(E). Titanium K-edge XAFS for TiSi2 was extracted from the reflectivity by `ReflXAFS'.
Synchrotron-radiation-induced formation of salt particles on an X-ray lithography mask
Authors: Utsumi Yuichi , Takahashi Jun-ichi , Hosokawa Teruo
Published: July 2004

The suppression and removal of contaminants on X-ray masks are required for the application of X-ray lithography to practical semiconductor production, because contamination is easily transferred to the replicated resist patterns and degrades the LSI patterns. In order to study contamination of a Ta/SiN X-ray mask, its growth process was investigated using an atmospheric reaction chamber and in situ observation apparatus for gases at atmospheric pressure. It was found that the contamination particles were ammonium sulfate and oxalate. The sources of the salt particle were also identified.
Synchrotron Radiation Lithography for Manufacturing Integrated Circuits Beyond 100 nm
Authors: Kinoshita Hiroo , Watanabe Takeo , Niibe Masato
Published: July 2004

Extreme ultraviolet lithography is a powerful tool for printing features of 0.1 µm and below; in Japan and the USA there is a growing tendency to view it as the wave of the future. With Schwarzschild optics, replication of a 0.05 µm pattern has been demonstrated in a 25 µm square area. With a two-aspherical-mirror system, a 0.15 µm pattern has been replicated in a ring slit area of 20 mm × 0.4 mm; a combination of this system with illumination optics and synchronized mask and wafer stages has enabled the replication of a 0.15 µm pattern in an area of 10 mm × 12.5 mm. Furthermore, in the USA, the Sandia National Laboratory has succeeded in fabricating a fully operational NMOS transistor with a gate length of 0.1 µm. The most challenging problem is the fabrication of mirrors with the required figure error of 0.28 nm. However, owing to advances in measurement technology, mirrors can now be made to a precision that almost satisfies this requirement. Therefore, it is time to move into a rapid development phase in order to obtain a system ready for practical use by the year 2004. In this paper the status of individual technologies is discussed in light of this situation, and future requirements for developing a practical system are considered.
Synchrotron radiation direct photo-etching of polymers and crystals for micromachining
Authors: Katoh T. , Zhang Y.
Published: July 2004

Synchrotron radiation etching of polymers and optical crystals which are transparent throughout the spectral range from visible to ultraviolet has been carried out without using any chemicals, successfully creating high-aspect-ratio microstructures for micromachining. A detailed study of the etching rates by varying the synchrotron beam current, sample temperature, beam size and aspect ratio showed that this synchrotron radiation process is essentially different from laser ablation, while an in situ mass spectrometric analysis of gaseous etching products showed that the dissociation mechanism involved with the synchrotron radiation processing, even with heating, is completely different from the thermal dissociation of the laser ablation.
Development of a two-dimensional imaging system for clinical applications of intravenous coronary angiography using intense synchrotron radiation produced by a multipole wiggler
Authors: Hyodo K. , Ando M. , Oku Y. , Yamamoto S. , Takeda T. , Itai Y. , Ohtsuka S. , Sugishita Y. , Tada J.
Published: July 2004

A two-dimensional clinical intravenous coronary angiography system, comprising a large-size view area produced by asymmetrical reflection from a silicon crystal using intense synchrotron radiation from a multipole wiggler and a two-dimensional detector with an image intensifier, has been completed. An advantage of the imaging system is that two-dimensional dynamic imaging of the cardiovascular system can be achieved due to its two-dimensional radiation field. This world-first two-dimensional system has been successfully adapted to clinical applications. Details of the imaging system are described in this paper.
In situ observation of phase transformation in an Fe–Zn system at high temperatures using an image plate
Authors: Kimura Masao , Imafuku Muneyuki , Kurosaki Masao , Fujii Siro
Published: July 2004

A unique system has been developed for in situ observation of phase transformation at high temperatures. Changes in powder-diffraction patterns from a heated specimen can be measured continuously by scanning an image plate located behind a slit. A heating system has been designed for a sheet specimen (∼5 × 6 mm) using Joule heating, and it can heat the specimen up to 1100 K at a rate of up to 160 K s−1, where effects of thermal expansion are minimized by a mechanism releasing stress. This system was applied to Zn-coated (∼8 µm in thickness) steel. At temperatures higher than the melting point of Zn, different types of Fe–Zn intermetallics formed sequentially through rapid interdiffusion. Changes in phase and crystallographic structure were monitored with a time resolution of less than a few seconds. It has been found that an addition of a small amount of an element, such as P, into Fe changes the incubation time before the alloying reaction starts. This system has been shown to have the potential for application to in situ observation of other reactions at high temperatures.
Beamline 14: a new multipole wiggler beamline for protein crystallography on the SRS
Authors: Duke E. M. H. , Kehoe R. C. , Rizkallah P. J. , Clarke J. A. , Nave C.
Published: July 2004

A new multipole wiggler device has been designed for the 2.0 GeV Synchrotron Radiation Source at Daresbury Laboratory in the UK. The nine-pole 2.0 T device will provide radiation for two beamlines dedicated to protein crystallography, one of which will be of high intensity. This article provides details of the design of the two stations and outlines methods being developed to combine dealing with the high heat load from the radiation while allowing both stations to be built as close to the centre of the fan as possible.
An eight-position capillary sample spinning stage for the diffractometer at BL20B at the Photon Factory
Authors: Creagh D. C. , Foran G. J. , Cookson D. J. , Garrett R. F. , Johnson F.
Published: July 2004

An eight-position capillary sample spinning stage has been developed for use in conjunction with the versatile vacuum diffractometer (BIGDIFF) at BL20B at the Photon Factory. BIGDIFF is often used in its powder diffraction mode using powders mounted in capillaries and up to eight imaging plates to record the diffraction pattern from the sample. Using the multiple spinning stage a number of diffraction patterns can be recorded on the imaging plates if the imaging-plate cassette is moved behind the Weissenberg screen to a new position after exposure of the sample to the beam. Not only is this system more efficient in terms of time saved in the pumping-down process, but also it has the advantage of allowing the diffraction patterns of standards to be recorded, thereby calibrating both the angle scale of the diffractometer and the intensity scales of the imaging plates absolutely.
Observation of the strain field near the Si(111) 7 × 7 surface with a new X-ray diffraction technique
Authors: Emoto Takashi , Akimoto Koichi , Ichimiya Ayahiko
Published: July 2004

A new X-ray diffraction technique has been developed in order to measure the strain field near a solid surface under ultrahigh vacuum (UHV) conditions. The X-ray optics use an extremely asymmetric Bragg-case bulk reflection. The glancing angle of the X-rays can be set near the critical angle of total reflection by tuning the X-ray energy. Using this technique, rocking curves for Si surfaces with different surface structures, i.e. a native oxide surface, a slightly oxide surface and an Si(111) 7 × 7 surface, were measured. It was found that the widths of the rocking curves depend on the surface structures. This technique is efficient in distinguishing the strain field corresponding to each surface structure.
Nanosecond-resolved XMCD on ID24 at the ESRF to investigate the element-selective dynamics of magnetization switching of Gd–Co amorphous thin film
Authors: Bonfim M. , Mackay K. , Pizzini S. , San Miguel A. , Tolentino H. , Giles C. , Neisius T. , Hagelstein M. , Baudelet F. , Malgrange C. , Fontaine A.
Published: July 2004

The one-bunch filling mode of the ESRF is combined with a microcoil to generate a pulsed-magnetic-field pump phased with respect to the probe that is given by the bunch of photons emitted each turn (357 kHz). Nanosecond-resolved X-ray magnetic circular dichroism (XMCD) is carried out. Besides the microcoil, the two other key-elements are the energy-dispersive XAS spectrometer, which yields parallel data acquisition, and the diamond-based quarter-wave plate, which tunes the helicity of the photon alternatively left and right.
Development of an (X, eX) spectrometer for measuring the energies of the scattered photon and recoil electron
Authors: Itou Masayoshi , Kishimoto Shunji , Kawata Hiroshi , Ozaki Makoto , Sakurai Hiroshi , Itoh Fumitake
Published: July 2004

The design and performance of a new spectrometer for coincidence measurements between the Compton scattered photon and the recoil electron are described. Coincidence measurements give direct information on the three-dimensional electron momentum density (EMD) of condensed matter. The present spectrometer measures energy spectra of both the photon and the electron. The energy spectrum of electrons is measured by a time-of-flight method using single-bunch operation at the Photon Factory Accumulator Ring (PF-AR). The energy resolution obtained for the recoil electron is 190 eV, which is better than that of the photon detector, so that a momentum resolution of the three-dimensional EMD of 0.3 atomic units can be achieved.
A new macromolecular oscillation camera at CHESS
Authors: Thiel Daniel J. , Blank Basil , LaIuppa Jim
Published: July 2004

Increasing X-ray flux and decreasing crystal size are two factors placing new demands on macromolecular diffraction cameras at synchrotrons. A new oscillation camera with high mechanical precision and fast rotation speed is described.
Application of a fine thread beam to the structure analysis of a hemihedrally twinned crystal of hydroxylamine oxidoreductase
Authors: Igarashi Noriyuki , Moriyama Hideaki , Tanaka Nobuo
Published: July 2004

Accurate diffraction intensity data have been collected from a twinned P63 crystal of the 24-haem protein hydroxylamine oxidoreductase, from a nitrifying chemoautotrophic bacterium Nitrosomonas europaea, using synchrotron radiation at station BL6A of the Photon Factory. Estimation of the twinning fraction and deconvoluted intensity data, including native and heavy-atom derivative data, gave an improved Patterson function. Four diffraction data sets were collected from one crystal and an estimation of the twinning fraction to confirm the phenomena was undertaken. The successfully detwinned data sets were utilized in the structure analysis of the present enzyme. The mechanism of twinned-crystal formation is also discussed.
Valence-difference contrast measurements utilizing X-ray anomalous scattering
Authors: Sasaki Satoshi , Toyoda Takeshi , Yamawaki Kouji , Ohkubo Koichi
Published: July 2004

Anomalous scattering experiments with X-ray wavelengths close to an absorption edge have made it possible to determine independently the behaviour of ions in different valence states. The anomalous scattering factors of Fe2+ and Fe3+ obtained from both absorption and diffraction data have a large difference in f′ between the two kinds of ions. Using a valence-difference contrast method, Bragg and diffuse scattering measurements were carried out for single crystals of Fe3O4 at low temperatures. The results demonstrate the ability of the contrast method to resolve charge ordering and valence fluctuation details.
Development of a compact six-circle goniometer
Authors: Tweet D. J. , Oyanagi H.
Published: July 2004

A compact versatile six-axis goniometer has been built which can be used with the scattering plane vertical or horizontal for anomalous X-ray diffraction and diffraction X-ray absorption fine structure using a tunable X-ray undulator at SPring-8. The diffractometer consists of a four-circle goniometer for the standard ω, 2θ, φ and χ motions and a two-circle goniometer on the 2θ arm for mounting the detector and analyser crystal. The goniometer is controlled via Ethernet, and standard data-acquisition software with a graphical user interface has been developed. A closed-cycle helium cryostat is mounted on the ω axis for temperature-dependent experiments from 330 K to 14 K. Preliminary experiments on a Bi2Sr2CaCu2O8 single crystal demonstrate the performance. Superstructure peaks due to the one-dimensional spatial modulations in the b axis were recorded as a function of temperature above 20 K using an image plate.
A synchrotron radiation beam-position monitor at the Taiwan Light Source
Authors: Chen J.-R. , Ueng T. S. , Hsiung G. Y. , Lin T. F. , Lee C. T. , Tsai S. L. , Chang S.-L.
Published: July 2004

A prototype photon-beam-position monitor has been designed, fabricated and tested at the Taiwan Light Source of the Synchrotron Radiation Research Center. Aluminium was chosen as the material of the blade electrodes due to its low atomic number and high thermal conductivity. The resolution of this photon-beam-position monitor was <±1 µm. The sensitivity of the blade electrode has been measured in situ. Results of measurements for bending-magnet light and undulator light with different gaps are described.
Magnetic measurement system for high-field magnets
Authors: Borovikov V. M. , Fedurin M. G. , Kerginsky A. N. , Kuzin M. V. , Mezentsev N. A. , Shkaruba V. A.
Published: July 2004

One of the main principles in electrodynamics, the change of magnetic field flux inducing an EMF in a wire coil, is applied for magnetic measurement. A scheme and the main parameters of the magnetic measurement system are described. The system was successfully used for magnetic measurement of a 7 T superconducting wiggler for LSU CAMD; results are presented.
Undulators at HiSOR – a compact racetrack-type ring
Authors: Hiraya Atsunari , Yoshida Katsuhide , Yagi Sinya , Taniguchi Masaki , Kimura Shin-ichi , Hama Hiroyuki , Takayama Takeshi , Amano Daizo
Published: July 2004

A compact racetrack-type 700 MeV storage ring (HiSOR) has been constructed at Hiroshima Synchrotron Radiation Center (HSRC). As the ring was planned for synchrotron radiation research on science and technology using VUV to X-rays up to 5 keV with limited size and cost, the ring was designed (i) to realize a high magnetic field (2.7 T) using conventional dipole magnets for higher critical energy, and (ii) to include two straight sections for insertion devices. A linear undulator (25–300 eV) and a new-type helical/linear undulator were installed at the two straight sections. The latter undulator consists of upper and lower jaws, as in a planar undulator; each jaw consists of one fixed magnet array at the centre and two magnet arrays on both sides. By longitudinal displacement of the side magnet arrays, the phase between the vertical and horizontal magnetic fields, and therefore the polarization (right- or left-circular, elliptical, linear) can be selected. The helical/linear undulator gives almost perfect circular polarization at 4–40 eV in the helical configuration without changing the phase of the magnet arrays, as well as linearly polarized light at 3–300 eV in the linear configuration.
Superconducting 7 T wiggler for LSU CAMD
Authors: Borovikov V. M. , Craft B. , Fedurin M. G. , Jurba V. , Khlestov V. , Kulipanov G. N. , Li O. , Mezentsev N. A. , Saile V. , Shkaruba V. A.
Published: July 2004

A superconducting 7 T wiggler is under fabrication in a collaboration between Budker INP and LSU CAMD. The wiggler magnet has been successfully tested inside a bath cryostat and a maximum field of 7.2 T was achieved after six quenches. The main parameters of the wiggler and the method of the wiggler installation onto the storage ring are discussed.
The operation of a superconducting wiggler at TERAS
Authors: Sugiyama S. , Ohgaki H. , Yamada K. , Mikado T. , Koike M. , Yamazaki T. , Isojima S. , Suzawa C. , Keishi T.
Published: July 2004

A superconducting wiggler has been successfully installed at the ETL 800 MeV electron storage ring facility (TERAS). The operation of the wiggler at magnetic field strengths of 5 T with electron beam energy of 750 MeV has been accomplished. The wiggler has been designed and constructed to produce synchrotron radiation with critical photon energy around 3 keV for scientific, industrial and medical applications. We report here experiments that demonstrate the possibility of stable operation of a superconducting wiggler in a small storage ring.
Design of a local bump feedback system for a variably polarizing undulator
Authors: Bizen Teruhiko , Shimada Taihei , Takao Masaru , Hiramatu Yoichi , Miyahara Yoshikazu
Published: July 2004

A local bump feedback system is under construction to correct the orbit distortion caused by the magnetic field errors of a double-array undulator used to generate linear and circular polarization of light for a soft X-ray beamline. The local bump orbit is created by steering coils several turns long and four sets of steering magnets. The kick angle of the long steering coils and the steering magnets is determined according to the motion of the undulator and by detecting the beam position.
X-ray absorption of bromonaphthalene dissolved in supercritical fluid xenon
Authors: Murata T. , Nakagawa K. , Otsuki Y. , Shimoyama I. , Mizutani T. , Kato K. , Hayakawa K. , Fujikawa T.
Published: July 2004

The results of Br K-edge X-ray absorption measurements of 1-bromonaphthalene dissolved in supercritical fluid Xe are reported. As the pressure of Xe confined in a high-pressure cell is increased, the absorption spectrum of bromonaphthalene gradually appears, showing that Xe in the supercritical fluid state solvates the bromonaphthalene molecule. The spectrum of the dissolved sample shows a remarkable difference from that of the pure liquid sample in the near-edge region of the X-ray absorption spectrum, reflecting the interaction of the solute material with solvent Xe. Ab initio full multiple-scattering calculations can reproduce the spectral features qualitatively. A large value of the Debye–Waller factor must be introduced to give the best fit, corresponding to a large degree of spatial disorder and violent thermal vibration of the Xe atoms around the Br atom.
Design study of a free-electron laser on a storage ring at Tohoku University
Authors: Feng B. , Oyamada M. , Sato S. , Sugawara M.
Published: July 2004

A free-electron laser (FEL) based on the proposed Tohoku Light Source storage ring is discussed. In the first stage the FEL is made to operate in the visible region with a relative low beam energy to avoid the complication of mirrors. Then, with a higher beam energy, the FEL can produce radiation of wavelengths in the UV or VUV region. Some simulation results of the storage-ring FEL with wavelengths of ∼200 nm are presented.
Present Status of the Pohang Light Source
Authors: Namkung Won
Published: July 2004

The Pohang Light Source (PLS), the first large-scale accelerator complex in Korea, is a national users facility for basic and applied science research using synchrotron radiation. It consists of a 2 GeV linac as a full-energy injector and a low-emittance storage ring. The PLS linac is 150 m long with eleven 80 MW klystrons for a high accelerating gradient; the storage ring has the TBA-lattice with 12 super-periods and a 280 m circumference. Since the accelerators were commissioned in December 1994, the annual operation time exceeded 4600 h in 1996, and the user service time is expected to reach 3500 h in 1997. The facility was opened to general users in 1995 with two beamlines. Six beamlines are now operating: white-beam, NIM for ARUPS and gas-phase, photoemission spectroscopy, EXAFS, X-ray diffraction and lithography. Our long-term plan is to construct three new beamlines every year.
Commissioning and Operation of the First Brazilian Synchrotron Light Source
Authors: Rodrigues A. R. D. , Craievich A. F. , Gonçalves da Silva C. E. T.
Published: July 2004

The synchrotron light source designed and constructed at the LNLS is composed of a 1.37 GeV electron storage ring and a 120 MeV linac for low-energy injection. The storage ring has been commissioned and has already reached the designed electron-beam energy, current and emittance. The electron lifetime is now 6 h at 60 mA, and is steadily increasing. Seven beamlines (TGM, SGM, SXS, XAFS, XRD, SAXS, PCr) have been constructed in parallel with the electron accelerators and are at present in operation. Beam time was allocated to 129 approved research projects for the second semester of 1997. A number of them are currently under way.
Compact Superconducting Ring at Ritsumeikan University
Authors: Iwasaki H. , Nakayama Y. , Ozutsumi K. , Yamamoto Y. , Tokunaga Y. , Saisho H. , Matsubara T. , Ikeda S.
Published: July 2004

A compact superconducting storage ring (0.575 GeV and 300 mA) with a racetrack microtron injection system was installed at Ritsumeikan University and has been operated successfully since April 1996. As the radius of the circular electron orbit is small (0.5 m), it is possible to use a radiation beam of relatively high photon flux at a short distance from the source point. Beamlines have been constructed including those for XAFS, soft X-ray spectroscopy, VUV spectroscopy, fluorescent X-ray analysis, soft X-ray microscopy, X-ray diffraction/scattering and photoelectron spectroscopy; the photoelectron spectrometer is combined with an ion-beam-scattering spectrometer to obtain information both on the electronic states and on the atomic arrangements of a solid surface. In addition there are two beamlines, one for LIGA exposure and the other for synchrotron radiation ablation, which are devoted to producing new devices and materials. The synchrotron radiation facility is open not only to users in the University but also to researchers in industry, governmental institutions and other universities.
Present Status of the UVSOR Facility – 1997
Authors: Kamada M. , Hama H. , Kinoshita T. , Kosugi N.
Published: July 2004

The UVSOR has been operational for nearly 14 years. In recent years, improvements to accelerators and beamlines have been carried out to obtain better performance and new scientific achievements. For example, a new type of helical undulator and a resonance transverse kicker were installed into the straight sections of the storage ring, and about one-third of the beamlines were upgraded by installing new monochromators and an interferometer. In addition, instruments and equipment were improved for research studies, with many interesting results. The most up-to-date information of the UVSOR facility is presented.
NSRL Phase II Project (a Brief Introduction and Status)
Authors: Liu Zuping , Zhang Xinyi
Published: July 2004

The Phase II Project is to be launched soon at NSRL, People's Republic of China. The main purpose of the project, an outline of its upgrade/expansion plans, and its present status are briefly described.
The Siam Photon Laboratory
Authors: Pairsuwan Weerapong , Ishii Takehiko
Published: July 2004

A synchrotron radiation research project, the Siam Photon Project, is underway in Thailand. The light source used in the project is the modified SORTEC storage ring. The project and simple aspects of the light source are described. The detailed design of the building to accommodate the experimental hall and the light source has been accomplished and the construction will start soon. The engineering design work of the machine components necessary for the modifications to reduce the beam emittance and to make the installation of insertion devices possible is underway.
The Hiroshima Synchrotron Radiation Center (HSRC)
Authors: Taniguchi Masaki , Ghijsen Jacques
Published: July 2004

The history of HSRC is briefly sketched, going back to the early HiSOR project. The present status of this 0.7 GeV compact storage ring is described and an outline of the future of the facility is given in the context of western Japan.
A new ion chamber with a movable photodiode monitor for absolute intensity measurements of soft X-rays
Authors: Cui Congwu , Cui Mingqi , Yi Rongqing
Published: July 2004

A new ion-chamber system with a movable monitor detector for the measurement of soft X-ray absolute intensity is introduced. The calibration results are also given.
A multiwire proportional counter for very high counting rates
Authors: Barbosa A. F. , Guedes G. P. , Tamura E. , Pepe I. M. , Oliveira N. B.
Published: July 2004

Preliminary measurements in a proportional counter with two independently counting wires showed that counting rates up to 106 counts s−1 wire−1 can be reached without critical loss in the `true versus measured' linearity relation. Results obtained with a detector containing 30 active wires (2 mm pitch) are presented. With each wire is associated a fast pre-amplifier and a discriminator channel. Global counting rates in excess of 107 events s−1 are reported. Dead-time losses are corrected by use of simple mathematical-modelling functions. Data-acquisition systems are described for one-dimensional (real-time) and two-dimensional (off-line) position-sensitive detection systems.
Detailed simulation of the response function of an Si(Li) detector
Authors: Goto Shunji
Published: July 2004

The response function of an Si(Li) detector was calculated by using a Monte Carlo method for photon energies below 10 keV. In the simulation, electron elastic-scattering cross sections calculated using the partial-wave expansion method were used instead of the Born approximation to simulate the electron scattering more accurately. The carrier collection probability near the gold–silicon interface was derived by solving the carrier continuity equation with drift, diffusion and surface recombination by a finite recombination velocity. For two detectors, good agreement was found for low-energy tailing between measured and simulated response functions. The integrated detection efficiency is almost identical with the transmittance in the front gold electrode showing a maximum difference of 2% at the Au M
4-absorption edge.
SPring-8 Program
Authors: Kamitsubo H.
Published: July 2004

SPring-8 is a third-generation synchrotron radiation source operating in the soft and hard X-ray region. It consists of an injector linac of 1 GeV, a booster synchrotron of 8 GeV and a storage ring with a natural emittance of 5.9 nm rad. The storage ring can accommodate 61 beamlines in total, and 26 of them are under construction. The project has been carried out jointly by JAERI and RIKEN and construction of the facility started in 1991. Commissioning of the injector linac was started in August 1996 and an 8 GeV electron beam was injected into the storage ring in March 1997. The first synchrotron radiation from a bending magnet was observed at the front end of the beamline on 25 March and radiation from an undulator was observed on 23 April. On-beam testing of seven beamlines, four of them from in-vacuum undulators and three from bending magnets, started in July. The maximum stored current is currently fixed at 20 mA and the lifetime at maximum current is longer than 20 h. The dedication is scheduled for October 1997.
Imaging soft X-ray microscope at Rits Synchrotron Radiation Center
Authors: Hirai A. , Takemoto K. , Nishino K. , Watanabe N. , Anderson E. , Attwood D. , Kern D. , Hettwer M. , Rudolph D. , Aoki S. , Nakayama Y. , Kihara H.
Published: July 2004

An imaging soft X-ray microscope with zone plates has been installed at Rits SR Center (Ritsumeikan University, Kusatsu, Japan). With this microscope, specimens were set in air, which made it possible to investigate the specimens without breaking the vacuum of the microscope. The specimens can be prefocused with an optical microscope. Dry and wet biospecimens in air were observed. A new optical system was designed to improve the resolution.
X-ray wideband in-line holography using a zone plate
Authors: Peiping Zhu , Mingqi Cui
Published: July 2004

X-ray wideband in-line holography, a new X-ray holography geometry using a zone plate, is proposed. The temporal coherence requirement in this geometry can be very low.
Imaging X-ray fluorescence microscope with a Wolter-type grazing-incidence mirror
Authors: Aoki S. , Takeuchi A. , Ando M.
Published: July 2004

A Wolter-type grazing-incidence mirror was used as an objective for an imaging X-ray fluorescence microscope. The microscope was constructed at the beamline 6C2 of the Photon Factory. The shortest wavelength used was ∼0. 1 nm, which was limited by the grazing-incidence angle of the mirror. To demonstrate the possibility of recording X-ray fluorescence images, several fine grids were used as test specimens. Characteristic X-rays emitted from each specimen could be clearly imaged. Spatial resolution was estimated to be better than 10 µm.
Stretched polymers for X-ray linear and circular polarization
Authors: Collins S. P.
Published: July 2004

X-ray linear dichroism at the iodine K-edge of Polaroid H-sheet is explored with a view to using stretched polymers for X-ray linear-polarization analysis. The potential use of such materials as phase plates for generating elliptically polarized beams is also considered.
Local structure study of dilute Er in III–V semiconductors by fluorescence EXAFS
Authors: Ofuchi H. , Kawamura D. , Tsuchiya J. , Matsubara N. , Tabuchi M. , Fujiwara Y. , Takeda Y.
Published: July 2004

For understanding the luminescence of Er atoms in III–V semiconductors, OMVPE-grown InP doped with Er has been investigated by fluorescence EXAFS (extended X-ray absorption fine structure) in order to study the local structure around Er atoms. The local structures around the Er atoms doped in InP, with doping as dilute as 3 × 1012 Er atoms in a 1.5 mm × 1.0 mm spot, were successfully measured by fluorescence EXAFS. The EXAFS analysis revealed that the Er atoms doped in InP above 853 K (which showed low luminescence) formed the rock-salt-structure ErP, while the Er atoms doped in InP below 823 K (which showed high luminescence) substituted on the In site of InP. The dependence of the local structure on growth temperature was observed for the samples doped with 3 × 1012 atoms and 1.2 × 1013 atoms of Er.
How X-ray Diffraction with Synchrotron Radiation Got Started
Authors: Holmes K. C. , Rosenbaum G.
Published: July 2004

The need to record low-angle-scattering X-ray fibre diagrams from muscle with millisecond time resolution drove the use of synchrotron radiation as an X-ray light source. The first smudgy diffraction patterns were obtained from a slice of insect flight muscle. Out of this grew the EMBL Outstation at DESY.
X-ray diffraction with a Bragg angle near π/2 and its applications
Authors: Kikuta S. , Imai Y. , Iizuka T. , Yoda Y. , Zhang X.-W. , Hirano K.
Published: July 2004

X-ray dynamical diffraction phenomena at a Bragg angle near π/2 are studied. The X-ray transmissivity as well as the reflectivity from the (991) lattice plane of a silicon thin plate is observed. It agrees fairly well with the diffraction pattern calculated on the basis of the Darwin approach. The possibility is discussed whether a set of two crystal plates arranged face to face, in which the diffraction condition with a Bragg angle near π/2 is satisfied, may be used as a very high resolution monochromator.
An assessment of approximating aspheres with more easily manufactured surfaces
Authors: Howells Malcolm R. , Anspach Joel , Bender John
Published: July 2004

In designing optical systems for synchrotron radiation, one is often led to conclude that optimal performance can be obtained from optical surfaces described by conic sections of revolution, usually paraboloids and ellipsoids. The resulting design can lead to prescriptions for three-dimensional optical surfaces that are difficult to fabricate accurately. Under some circumstances satisfactory system performance can be achieved through the use of more easily manufactured surfaces such as cylinders, cones, bent cones, toroids and elliptical cylinders. These surfaces often have the additional benefits of scalability to large aperture, lower surface roughness and improved surface figure accuracy. In this paper we explore some of the conditions under which these more easily manufactured surfaces can be utilized without sacrificing performance.
Bent-crystal monochromators for high-energy synchrotron radiation
Authors: Yamaoka Hitoshi , Mochizuki Tetsuro , Sakurai Yoshiharu , Kawata Hiroshi
Published: July 2004

Two kinds of monochromators covering the energy ranges 100–150 keV and ∼300 keV have been designed for inelastic (Compton) scattering experiments at the elliptical multipole wiggler beamline, BL08W, of SPring-8. Finite-element analyses using ANSYS for bent crystals indicate that thermal problems are not serious for the 300 keV monochromator, while an energy spread of about 10−3 for the 100–150 keV monochromator is possible in the centre of the crystal. Detailed calculations of X-ray interaction with the silicon crystal were performed. The results show that Compton scattering is a dominant process and deposits about 100 W continuously.
Focusing and reflection by a bent crystal for high-energy synchrotron radiation
Authors: Yamaoka Hitoshi , Ohtomo Kiyotaka , Ishikawa Tetsuya
Published: July 2004

The focusing properties and resolution of a doubly bent crystal in the Bragg case have been analytically studied from a geometrical viewpoint. Simulation using the Takagi–Taupin equations was also performed for singly bent crystal reflections to study the reflectivity. The critical radius of curvature for changing from dynamical to kinematical diffraction is calculated to be of the order of a few tens of metres for an Si 400 reflection of 110 keV X-rays.
Optimization strategies for XUV monochromators
Authors: Polack François , Delcamp Eric , Lagarde Bruno , Mirone Alessandro
Published: July 2004

The techniques of monochromator optimization are reviewed, and it is shown that until recently only a few of the available parameters were used at the same time. Efficient optimization can be performed numerically. The computation method developed at LURE is explained and an example is given. Extension and development of the method are outlined.
X-ray absorption fine structure of V2O5 and Li
x
V2O5
Authors: Yiwata Noriyuki , Watada Atsuyuki , Yamamuro Tetsu , Hayashi Yoshitaka , Ohsawa Toshiyuki , Fujikawa Takashi , Tani Katsuhiko
Published: July 2004

Vanadium K-edge XAFS measurements of five compounds were carried out. The compounds studied were crystalline V2O5 and four types of Li
x
V2O5 with different insertion levels x, which show different EMFs (2.0–3.4 V). The EXAFS data analysis shows no remarkable difference in the V—O distances in the five compounds, showing that the structure of the VO5 square pyramids changes only slightly as lithium atoms are intercalated into the V2O5. In the XANES spectra, three peaks are observed for crystalline V2O5 and Li
x
V2O5 (3.4 V). When the EMF is decreased, the intensity difference between the first and second peaks disappears and the third peak shifts to lower energy. The XANES data were analysed using full multiple-scattering calculations. In the calculated spectra the intensity of the first peak increases as the V2O5 intercalates lithium atoms.
Medical Applications with Synchrotron Radiation in Japan
Authors: Takeda Tohoru , Itai Yuji , Hyodo Kazuyuki , Ando Masami , Akatsuka Takao , Uyama Chikao
Published: July 2004

In Japan, various medical applications of synchrotron X-ray imaging, such as angiography, monochromatic X-ray computed tomography (CT), radiography and radiation therapy, are being developed. In particular, coronary arteriography (CAG) is quite an important clinical application of synchrotron radiation. Using a two-dimensional imaging method, the first human intravenous CAG was carried out at KEK in May 1996; however, further improvements of image quality are required in clinical practice. On the other hand, two-dimensional aortographic CAG revealed canine coronary arteries as clearly as those on selective CAG, and coronary arteries less than 0.2 mm in diameter. Among applications of synchrotron radiation to X-ray CT, phase-contrast X-ray CT and fluorescent X-ray CT are expected to be very interesting future applications of synchrotron radiation. For actual clinical applications of synchrotron radiation, a medical beamline and a laboratory are now being constructed at SPring-8 in Harima.
Tensometry of carbon fibres and elastomers at the diffractometer at BL20B of the Photon Factory
Authors: Creagh D. C. , O'Neill P. M. , Mills R. J. , Holt S. A.
Published: July 2004

Two systems have been developed for the simultaneous recording of the SAXS and the WAXS patterns from carbon fibre and elastomer samples which are placed under stress. The systems have been designed to fit inside the versatile vacuum diffractometer (BIGDIFF) at the Photon Factory. In one system, use is made of the ability to move the imaging-plate cassette. In the other, use has been made of an imaging-plate changer which can deliver up to 13 plates into position with a duty cycle of about 60 s. In this case each imaging plate can record SAXS/WAXS patterns in the range 0.5–20° due to the passage of the beam through the specimen which is mounted in a specially designed tensometer. Because BIGDIFF is a vacuum diffractometer and parasitic scattering is small, exposure times as short as 2 s can give acceptable SAXS/WAXS patterns. The systems have been used for the study of both the change of structure with strain, and the relaxation processes which occur as a result of the sample being strained at a fixed rate by a predetermined amount.
Object library for a new generation of experiment-controlling applications under the UNIX operating system
Authors: Gaponov Yu. A. , Ito K. , Amemiya Y.
Published: July 2004

The Interface Object Library based on the Motif extension of the X Windows system and on the ESONE SVIC-VCC Library is presented. Some features of the applications for controlling a synchrotron radiation experiment are discussed. The Interface Object Library is written in the object-oriented C++ language. The library class-hierarchy structure is presented and discussed. Several interfaces were realized in the Interface Object Library: the Windows interface, the CAMAC interface and the interface for supporting the experiment. The behaviour of the objects describing the CAMAC crate and CAMAC block is discussed. The application of these protocols for controlling the fast one-coordinate position-sensitive X-ray detector OD3 is presented.
Present Status of SPring-8 Insertion Devices
Authors: Kitamura Hideo
Published: July 2004

According to the general policy, namely, the pursuit of pure radiation without any unreasonable heat load, the construction of various insertion devices has been scheduled at SPring-8. Most of them are of the in-vacuum type, which makes it possible to realize short-period devices, so that the fundamental of undulator radiation may be obtained in the hard X-ray region. In addition, undulator radiation in the soft X-ray range down to 100 eV is available by introducing helical or figure-8 devices having low on-axis power density, which is very beneficial for the optics, gratings or mirrors. A brief overview of the insertion devices at SPring-8 is presented with the initial commissioning results.
Synchrotron Radiation Sources – Present Capabilities and Future Directions
Authors: Winick Herman
Published: July 2004

Many of the more than 40 operational light sources around the world have achieved performance levels that exceed initial design goals. These accomplishments are reviewed, along with concepts and proposals for sources with performance levels exceeding those of present sources. These include storage rings with lower electron-beam emittance than present third-generation rings and free-electron lasers (FELs). It now appears that the highest performance sources will be based on linacs rather than storage rings. This is because emittance originates differently and scales differently with electron energy for rings and linacs, so that the lowest electron-beam emittance can be achieved in high-energy linacs equipped with high-brightness electron sources. Such electron beams can be used to provide X-ray beams with very high brightness and coherence in sub-picosecond pulses in a single pass through a small-gap short-period undulator by spontaneous emission, and with even higher beam brightness and coherence by stimulated coherent emission in an FEL. Designs for such FEL sources, and associated research and development, are underway at several laboratories.
Proposal of a high-field superconducting wiggler for a slow positron source at SPring-8
Authors: Ando A. , Daté S. , Fedurin M. G. , Hara M. , Kamitsubo H. , Kiselev A. V. , Kulipanov G. N. , Kumagai N. , Mezentsev N. A. , Miyahara Y. , Nakamura T. , Ohkuma H. , Shkaruba V. A. , Skrinsky A. N. , Soutome K. , Takao M. , Tanaka H.
Published: July 2004

A low-energy positron beam is a unique probe of materials. In high-energy electron and positron storage rings it is possible to generate intense synchrotron radiation with a photon energy of 1–3 MeV by installing a high-field (8–10 T) superconducting wiggler. High-energy photons are converted to low-energy positrons by using a suitable target–moderator system. For an 8 GeV electron storage ring at a beam current of 100 mA, final yields are estimated to be about 108–1010 slow-e+ s−1 or larger depending on the moderation efficiency, with the size of the positron source 101–102 cm2. In the present work a wiggler magnetic system of 10 T is proposed. The main parameters of the superconducting wiggler are presented.
ID14 `Quadriga', a Beamline for Protein Crystallography at the ESRF
Authors: Wakatsuki S. , Belrhali H. , Mitchell E. P. , Burmeister W. P. , McSweeney S. M. , Kahn R. , Bourgeois D. , Yao M. , Tomizaki T. , Theveneau P.
Published: July 2004

The ESRF undulator beamline ID14 `Quadriga' is dedicated to monochromatic macromolecular crystallography. Using two undulators with 23 mm and 42 mm periods and a minimum gap of 16 mm installed on a high-β section, it will provide high-brilliance X-ray beams at around 13.5 keV, as well as a wide tuneability between 6.8 and 40 keV. Based on the Troika concept, this beamline has four simultaneously operating experimental stations: three side stations, EH1, EH2 and EH3, using thin diamond crystals, and an end station, EH4, with a fast-scan double-crystal monochromator. Station EH3 has a κ-diffractometer, and an off-line Weissenberg camera with a large 80 × 80 cm active area combined with a 2048 × 2048 CCD detector. During data collection the image plates are placed and removed by a robot located inside the hutch using a cassette system. After data collection the image plates are scanned with an off-line drum scanner. Station EH4 is designed for MAD applications, including Xe K-edge anomalous experiments, and is equipped with a 2048 × 2048 CCD detector on a pseudo 2θ arm. A common graphical user interface and a database will be available to cover all aspects of data collection, including strategy optimization. First results on the performance of the optics elements and initial crystallographic results are presented.
X-ray microprobe system for XRF analysis and spectroscopy at SPring-8 BL39XU
Authors: Hayakawa Shinjiro , Goto Shunji , Shoji Takashi , Yamada Eiji , Gohshi Yohichi
Published: July 2004

An X-ray microprobe system for X-ray fluorescence (XRF) analysis and spectroscopy has been developed at SPring-8 BL39XU; it comprises an X-ray focusing or collimation system, energy-dispersive (ED) and wavelength-dispersive (WD) XRF spectrometers, and a sample-scanning system. The conventional ED spectrometer will be utilized for qualitative and quantitative trace-element analysis, and the WD spectrometer will be used both for trace-element analysis and XRF spectroscopy. A combination of monochromated undulator radiation and the WD spectrometer will enable resonant XRF spectroscopy using brilliant hard X-ray undulator radiation.
X-ray contact microscopy system for spectromicroscopy of biological specimens
Authors: Ito Atsushi , Shinohara Kunio , Mizukami Yutaka , Nakano Hisako , Yada Keiji , Uehara Takayuki , Honda Toshio
Published: July 2004

An X-ray contact microscopy system has been developed for the study of molecular and elemental distributions in biological specimens based on X-ray absorption characteristics. The system consists of a chamber for measuring XANES (X-ray absorption near-edge structure) of biomolecules, and a contact microscopy system for dried specimens with an electronic zooming tube. With this system the elemental distribution of carbon, nitrogen, oxygen, Ca and Fe in an HeLa cell has been studied, and the DNA-related image using a peak from the XANES profile of the DNA at the K-absorption edge of phosphorus has been obtained.