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For the operation of the WASA (Wide Angle Shower Apparatus) detector system at the Cooler Synchrotron COSY in Forschungszentrum Julich (FZJ) a new DAQ system has been developed, which conforms to the third generation of the DAQ systems at COSY. This comprises new readout electronics based on an optimized parallel bus with LVDS technology and FPGA-controlled event and buffer management. The new DAQ system has been successfully commissioned in autumn 2006. Further developments aiming at performance optimizations are in progress. The implementation status is presented and performance issues are discussed.

Particle physics collider experiments at the high energy frontier are being performed in increasingly harsh radiation environments. While designing adequate detectors is a challenge in itself, their safe operation relies on fast, radiation-hard beam condition monitoring (BCM) systems to protect these fragile devices from beam accidents. This paper will present a BCM system based on polycrystalline chemical vapor deposition (pCVD) diamond sensors used at the Collider Detector at Fermilab (CDF) experiment operating at Fermilab's Tevatron proton-antiproton synchrotron. We report our operational experience with this system, including the recently commissioned abort system. The system is currently the largest of its kind at a hadron collider. It is similar to designs being pursued at the CERN Large Hadron Collider (LHC) experiments. Index Terms--Accelerators, diamond, particle beam stability, radiation detectors, radiation monitoring.

The article describes a medium-energy, injector-free synchrotron, which employs a strong focusing lattice for ion-beam guiding and hence is capable of accelerating ions of all the species. The synchrotron acts injector-free due to the synchronization of bunch circulation with the acceleration, which is commonly caused due to the energizing of the switching power supply by the trigger signal.

Melanophlogite, a clathrasil, possesses a framework of corner-linked silica tetrahedra forming framework cavities that can enclose small guest molecules. Synchrotron X-ray diffraction experiments of the guest-free melanophlogite have been conducted at pressures up to 12 GPa and temperatures up to 1473 K. Upon compression at room temperature, melanophlogite gradually lost its crystallinity and became completely X-ray amorphous at ~8 GPa. The amorphization process was similar to those of denser silica polymorphs, but it reached completion at a much lower pressure (e.g., quartz becomes X-ray amorphous at ~30 GPa). The decreased amorphization pressure of melanophlogite may be attributed to its lower framework density and the ease of bending of its Si-O-Si linkages, thereby accelerating the collapse of the structure under high pressure. Determination of cell volumes of melanophlogite prior to its amorphization yielded a room-temperature bulk modulus of 26.3 [+ or -] 1.7 GPa, which is consistent with the relatively large compressibilities reported for the structurally similar zeolites. When heated at -8 GPa, the amorphous phase started to crystallize at 873 K into coesite, the stable silica phase at these pressure and temperature conditions. Thus the occurrence of pressure-induced amorphization in melanophlogite appears to result from the kinetic hindrance to its transformation to the thermodynamically stable coesite. Keywords: Melanophlogite, clathrasil, pressure-induced amorphization, compressibility, synchrotron X-ray diffraction

Despite the abundance of garnet in deforming regions of the Earth, such as subduction zones, its rheological properties are not well defined by laboratory measurements. Here we report measurements of steady-state plastic properties of pyrope in its stability field (temperature up to 1573 K, pressure up to 6.8 GPa, strain rate ~[10.sup.-5] [s.sup.-1]) using a Deformation-DIA apparatus (D-DIA) coupled with synchrotron radiation. Synthetic pyrope ([Py.sub.100]) and natural pyrope ([Py.sub.70][Alm.sub.16][Gr.sub.14]) are both studied in a dry environment. Transmission electron microscopy (TEM) investigation of the run products indicates that dislocation glide, assisted by climb within grains and dynamic recrystallization for grain-boundary strain accommodation, is the dominant deformation process in pyrope. Both synthetic-and natural-pyropes' stress and strain-rate data, as measured in situ by X-ray diffraction and imaging, are best fitted with the single flow law: [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] where [??] is the strain rate, [sigma] = [absolute value of [sigma.sub.1] - [sigma.sub.3]] is the differential stress, R is the gas constant and T the absolute temperature. Synthetic forsterite and synthetic pyrope were stacked along the uniaxial compression direction in the same cell assembly during deformation to compare their strength at mantle condition. Forsterite is observed to be stronger than pyrope, deforming at a rate about 10% slower than the pyrope at 5.2 GPa and 1573 K. San Carlos olivine and natural pyrope were compared in a similar fashion at 6.8 GPa and 1473 K. In this case, San Carlos olivine deformed 2~3 times faster than natural pyrope. The experimental data suggest that pyrope is stronger (by more than a factor of 4) than the dominant mineral (olivine) in the upper mantle when temperatures exceed 1273 K. Keywords: Garnet, high pressure, high temperature, synchrotron X-ray imaging, stress, strain

Rietveld refinements using neutron powder diffraction data were used to locate H atom positions and obtain a more precise crystal structure refinement for akaganeite [[Fe.sup.3+.sub.7.6][Ni.sup.2+.sub.0.4] [O.sub.6.35] [(OH).sub.9.65][Cl.sub.1.25]*n[H.sub.2]O]. Difference Fourier maps clearly showed H atoms positions near those O atoms at the midpoints of the tunnel edges. The O-H vectors point toward the Cl sites at the center of the tunnel, and weak hydrogen bonds likely form between the framework O atoms and Cl. The Cl position is near the center of a prism defined by the eight hydroxyl H atoms. The Cl atoms fill ~2/3 of the tunnel sites, suggesting an ordering scheme in a given tunnel with every third tunnel site vacant. Such an arrangement allows the Cl anions to increase their separation distance along a tunnel by displacing away from one another toward their respective adjacent vacancies. The Fe-O octahedra in akaganeite are distorted with Fe-(O, OH) distances ranging from 1.94 to 2.13 [Angstrom] and show three longer and three shorter Fe-O distances; as expected the longer distances are associated with the O[H.sup.-] anions. Temperature-resolved synchrotron X-ray powder diffraction data and Rietveld refinements were used to investigate changes in the akaganeite structure and its transformation into hematite as it was heated from 26 to 800 [degrees]C. Rietveld refinements revealed surprising consistency in all unit-cell parameters between room temperature and -225 [degrees]C, resulting in nearly zero thermal expansion of the akaganeite structure over a 200 [degrees]C interval. Above -225 [degrees]C, the unit-cell volume gradually decreased, primarily in response to decreases in c and b, and an increase in the [beta] angle. The a parameter remained nearly constant until ~225 [degrees]C and increased thereafter. Akaganeite started to transform to hematite in the temperature range 290 to 310 [degrees]C with no evidence for maghemite as an intermediate phase.

The generation and evolution of defects in 4H-SiC p-n junctions due to carrier injection under forward bias are investigated by synchrotron white beam x-ray topography, electroluminescence imaging, and KOH etching. Low angle grain boundaries are observed to act as one of a number of possible nucleation sites of stacking faults.

Synchrotron micro-XRF, a trace-level microanalytical method, allows quantitative study of the nature and degree of heterogeneity of inorganic trace constituents in solid materials with a homogeneous matrix. In this work, the standard reference materials NIST SRM 613, Trace Elements in 1 mm Glass Wafers, and NIST SRM 1577a, Trace Elements in Bovine Liver, are examined at the 10-100-ng mass level using X-ray beams of 5-150 [micro] m in diameter. A procedure based on a large number of repeated analyses of small absolute amounts of the SRMs allows calculation of the minimal representative mass of the standard. The microheterogeneity of both NIST SRM 613 and NIST SRM 1577a was investigated with the aim of evaluating their suitability as reference materials for trace-level microanalytical techniques. A Monte Carlo simulation model was constructed for both homogeneous and heterogeneous materials to elucidate the dependence of the calculated minimal representative mass on the total analyzed mass in the case of materials that show strongly heterogeneous features at the microscopic level.

In situ synchrotron X-ray experiments of the Ge[O.sub.2] system were made at pressures of 28-45 GPa and temperatures of 300-2300 K, using a diamond anvil cell combined with a laser heating and a 6-8 type multianvil high-pressure apparatus. We observed a second-order phase transition between tetragonal rutile-type (P[4.sub.2]/mnm) and orthorhombic Ca[Cl.sub.2]-type (Pnnm) phases under high pressure and temperature. The transition kinetics seem to have little effect on the second-order phase transition because the cell constants exhibit no discontinuities between the phases. Therefore, the phase transitions could be observed at low temperature conditions in this study. The phase boundary was determined to be P (GPa) = (34.9 [+ or -] 1.2) + (0.0086 [+ or -] 0.0024) x (T - 1300) (K).

Research has been conducted on the synchrotron-based X-ray microprobes. The generic configurations and experimental strategies used in conducting the spatially resolved soft X-ray spectroscopy and synchrotron-based X-ray spectroscopy are discussed.

Spatial analysis of superconducting tunnel junction x-ray detectors is achieved using a low temperature scanning synchrotron microscope.

Intramyocardial vessels in eight dogs were examined via synchrotron microangiography. It was observed that myocardial contraction reduced the vascular short-axial diameters of the end-diastolic values and increased the longitudinal dimension. To-and-fro blood flow was observed in penetrating transmural arteries with visual identification of capacitive backflow, resistive forward flow during ischemia on coronary arteriography, and even under baseline conditions in coronary venography.

The structure of a new crystal form of methanol dehydrogenase derived from Methylophilus W3A1 was studied using data recorded at a synchrotron. At 1.9 angstrom resolution, details of the configuration of the redox factor pyrroloquinoline quinone (PQQ) were observed. C4, one of the oxygen-bearing atoms, is in a planar configuration while C5, which bears the other quinone oxygen, is tetrahedral. These suggest that PQQ is in the semiquinone redox state.

An experiment was conducted to determine, characterize and prepare the crystal structure of the innovative 3-dimensional hydrogen phosphate. To determine the complete crystal structure, the combined synchrotron X-ray single-crystal diffraction and neutron powder diffraction methods were utilized. Results showed that the structure is described as a 3-dimensional framework built from ZrO6 octahedra which are bound together by hydrogen phosphate groups (PO3(OH)).

Photon electron spectroscopy was utilized to investigate the adsorbate system of C60 - nickel(110). Substantial broadening of the leading valence band feature with constant binding energy was seen through the investigation of the valence photoelectron spectra as a function of the C60 coverage. Such a result was homologous with the strong chemical interactions between the first carbon 60 monolayer and the nickel substrate.

White-beam synchrotron X-ray topographic studies of twin structures in NdP5O14 single crystals reveals that the a-type twins along the a-axis are displaced. The displacement measurement indicates presence of monoclinic distortion associated with unit cell parameters. The twin structure of NdP5O14 is obtained from the fine-beam Laue diffraction pattern of the compound.

A new high-resolution quantitative method of examining quick alterations of the fluid amount present in porous media, was provided by synchrotron X-rays at the Cornell High Energy Synchrotron Source. This method is founded on controlling X-ray absorbance alterations in sand volumes crossed by an acute, highly collimated synchrotron X-ray beam. This method helps assess the physical and chemical characteristics of a rapid flow field in porous media.

Synchrotron X-ray and neutron powder diffraction were used together to ascertain the crystal structure of Ga2(HPO3)3.4H2O, which has 29 atoms in the asymmetric unit cell and 117 structural parameters. Using these two methods to complement each other overcomes the disparity between powder data and Rietveld profile data that had previously impeded determining crystal structure from powder diffraction.

The pressure-induced structural phase transition of spin ladder compound SrCu(sub 2)O(sub 3) is studied by synchrotron X-ray powder diffraction with a diamond anvil cell. The result of the structure determination of the high-pressure phase is found to be essentially the same as that of CaCu(sub 2)O(sub 3).

Compressibility of the 6H polytype of moissanite (SiC) up to a pressure of 68.4 gigapascals is measured using a diamond anvil cell with synchrotron radiation. The pressure was caliberated using gold, and sodium chloride was used as the medium of transmitting pressure. The usage of a very small X-ray beam of 0.015 millimeter in diameter reduces the pressure gradient's effects. The usage of a large volume of sodium chloride enables a reduction in the uniaxial stress. Molar volumes and 101 and 102 peaks of the SiC are also obtained.

The pressure-induced rocksalt phase of aluminum nitride at ambient condition was investigated. Experiments were performed wherein polycrystalline aluminum nitride samples were subjected to ultahigh pressure using a diamond anvil cell. Energy-dispersive x-ray diffraction measurements were then taken by means of a synchrotron x-ray source. Results show that the samples exhibit a first-order transformation from wurtzite to a rocksalt structure un der a pressure of 65 gigaPascals.

The European Synchrotron Radiation Facility in Grenoble, France allows archaeologists to examine objects at a molecular scale. The use of this technology in archaeology is described through several archaeological researches that include the study of the childhood development of early humans and the blackening of Pompeii.

Synchrotron spectromicroscopy experiments are used for showing that stacks of aragonite tablet crystals in nacre are misoriented with respect to each other. The results have shown that the self-ordering of the mineral phase, which has occurred independently of biological or organic-molecule control, is fundamental in the formation of nacre.

The synthesis and synchrotron x-ray diffraction measurements of nanocrystalline (nc) silicon carbide (SiC) with a diameter of 7 nm in a high voltage electrical explosion are reported. The smaller bulk modulus of nc is caused by the weaker atomic bonding strength and the imperfections of the nc SiC.

Research has been conducted on solvent-free potassium, rubidium and cesium oxalates. The authors report the study of the molecular and crystal structures of these compounds determined via the use of high-resolution synchrotron and X-ray laboratory powder patterns.

Synchrotrons have long been the preferred X-ray sources for crystallography, but competition has arrived with the advent of X-ray free-electron lasers. A synchrotron expert and an advocate of free-electron lasers [...]

The recent interest in extreme-ultraviolet (EUV) lithography has led to the development of an array of at-wavelength metrologies implemented on synchrotron beamlines. These beamlines commonly use Kirkpatrick--Baez (K--B) systems consisting of two perpendicular, elliptically bent mirrors in series. To achieve high-efficiency focusing into a small spot, unprecedented fabrication and assembly tolerance is required of these systems. Here we present a detailed error-budget analysis and develop a set of specifications for diffraction-limited performance for the K--B optic operating on the EUV interferometry beamline at Lawrence Berkeley National Laboratory's Advanced Light Source. The specifications are based on CODE V modeling tools developed explicitly for these optical systems. Although developed for one particular system, the alignment sensitivities presented here are relevant to K--B system designs in general. OCIS codes: 340.6720, 220.2740, 220.4830, 220.1010, 220.1140.

ANKARA--A long-planned synchrotron project for the Middle East took a major step forward last month after its Jordanian hosts pledged the money to house the instrument and its German donors [...]

Synchrotron X-ray powder diffraction study of brucite, Mg[(OH).sub.2], was carried out in a diamond anvil cell with an imaging plate detector from 0.6 to 18.0 GPa at room temperature using the angular-dispersive technique on beamline BL-18C at the Photon Factory, KEK, Japan. Using Rietveld analysis, unit-cell parameters as well as atomic positions of the O atoms in brucite have been successfully refined, taking into account the effects of preferred orientation. Variation of the c/a ratio with pressure indicates that the compression mechanism changes around 10 GPa, above which the compression behavior is isotropic. Based on the changes of the refined atomic positions of the O atoms with pressure, we conclude that the shortening of the interlayer distance controls compression below 10 GPa, whereas above this pressure compression of the oxygen sublattice is the dominant mechanism. Results of the structural refinements also suggest that the Mg[O.sub.6] octahedral regularity initially approaches a regular configuration with pressure, which then remains unchanged above 10 GPa.

The National Synchrotron Light Source II, a high-energy photon source at Brookhaven National Laboratory in Upton, New York, produced its first photons on 23 October--a major milestone towards achieving full [...]

The advent of third generation hard x-ray synchrotron facilities have greatly enhanced research in many fields. In biology, the exponential growth and successes in solving protein structures (protein crystallography) using synchrotron radiation is well known. However, other fields within biology such as morphology, biomechanics, and physiology can also benefit from these facilities. After a brief introduction to synchrotron radiation, this paper will describe recent progress in the field of x-ray imaging and discuss its applications in the biosciences. In particular, the recent advances in phase-enhanced imaging have greatly improved the visibility and contrast of images in a range of biological samples. Coupled with the unsurpassed beam brightness, this has enabled real-time x-ray studies on living insects. Examples of insect respiration and the mechanics of mouth-part function will be shown. Another important imaging technique is tomography. Recent advances in this field provide the researcher with an opportunity to view 3-D volume images with micron-level resolution. Internal structures, in their natural state, can thus be studied without resorting to dissection or histology. Examples with insects and seeds will be shown. Finally, the procedure to access the experimental facilities at the Advanced Photon Source at Argonne National Laboratory in Illinois will be described. The APS is supported by the US Department of Energy, Office of Science, contract no. W-31-109-Eng-38.

The operation and maintenance of the International Centre for Synchrotron light for Experimental Science and Applications in the Middle East (SESAME) in Jordan by UNESCO and European Commission are discussed.

The polymerization of Ge4S10 tetrahedral clusters bridged by 2-coordinated Cu(I) cations leads to the formation of a copper germanium sulfide, CuGe2S5.(C2H5)4N, having a diamond-like framework and the tetraethylammonium template cations occupying their openings. The structure established from the synchrotron imaging plate data possess four-connected Ge4S10(super 4-) tetrahedral clusters with the centers situated at the framework's nodes.

Resting insects primarily ventilate through diffusion and abdominal pumping, while many flying insects cope with increased oxygen demands by utilizing thoracic autoventilation, in which wing movements cause volume changes in the thorax that ventilate thoracic air sacs. Measurement of autoventilation is difficult and has only been performed on dead grasshoppers and dragonflies where convective air movement was induced by mechanical movement of the wings to simulate flight. However, synchrotron phase-enhanced x-ray imaging permitted us to visualize compression of air sacs between major dorsoventral flight muscles in tethered, flying Schistocerca americana grasshoppers and Pachidiplax longipennis dragonflies. This method provides a new and exciting method of quantifying thoracic autoventilation in a live insect during flight. This research was partially funded by NSF IOB--0419704 awarded to JFH.

Crystal Structures at Megabar Pressures Determined by Use of the Cornell Synchrotron Source X-RAY DIFFRACTION STUDIES ON MATERIALS subjected to high pressures provide direct information about pressure-induced crystallographic phase transitions [...]