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Three bronze vessels from the ancient Chinese art collection at the Art Institute of Chicago (AIC) were examined—with the advanced non-invasive characterization capabilities of high-energy synchrotron X-ray diffraction performed at the Advanced Photon Source (APS) of Argonne National Laboratory (ANL)—to create a comprehensive overview of each object’s manufacture as well as subsequent corrosion processes. Findings were also complemented with traditional non-invasive characterization techniques, including optical imaging, X-ray radiographic imaging, and X-ray fluorescence (XRF) spectrometry. The results—obtained without sampling—allow a clear distinction between genuinely ancient Chinese bronzes from those with modern restorations and from “archaistic” objects made many centuries later, in emulation of ancient styles.

Interpenetrating Al 2 O 3 /Al composites were created by liquid-metal infiltration of 3D periodic ceramic preforms with face-centered-tetragonal symmetry produced by direct-write assembly. Volume-averaged lattice strains in the ceramic phase of the composite were measured by synchrotron X-ray diffraction for various levels of uniaxial compression stresses. Load transfer is found to occur from the metal phase to the ceramic phase, and the magnitude of the effect is in general agreement with simple rule-of-mixtures models. Spatially resolved diffraction measurements show variations in load transfer at two different positions within the composite for the elastic- and damage-deformation regimes, the latter being observed using phase-enhanced synchrotron imaging. The mechanical behavior of these interpenetrating Al 2 O 3 /Al composites with face-centered-tetragonal symmetry are compared with previous interpenetrating Al 2 O 3 /Al composites with simple-tetragonal symmetry.

High-energy synchrotron X-ray diffraction and imaging experiments were performed at the Advanced Photon Source on two ancient Chinese bronzes from the Art Institute of Chicago with the goal to nondestructively study their microstructure. The first object, a bronze fragment from an early Western Zhou dynasty vessel (Hu, 11th/10th century B.C.), was investigated with spatially-resolved diffraction to reveal the depth and composition of the surface corrosion layer as well as the composition and grain size of the underlying bronze core. The second object, a bronze dagger-axe (Ge, 3rd/2nd century B.C.) with a silver-inlaid sheath, was studied under both diffraction and imaging conditions. It was found to have been cast as a single object, answering longstanding scholars’ questions on whether the ceremonial object concealed an interior blade.

Synchrotron X rays were used to perform nondestructive transmission diffraction and fluorescence experiments on a group of 24 European and Islamic astrolabes dated between 1350–1720 A.D. in order to determine their compositions. A group of six astrolabes produced in Lahore between 1601–1662 A.D. were found to contain a mixed α+β brass microstructure, proving that the brass was produced by a comelting technique rather than the traditional cementation process. The results also show evidence of dezincification, attributed to heavy annealing of the brass during astrolabe manufacture. This effect was so severe that an accurate analysis of the bulk Zn composition could not be determined from the fluorescence results alone; transmission X-ray diffraction gives a more accurate measurement of the bulk Zn composition.

High-energy synchrotron diffraction offers great potential for experimental study of recrystallization kinetics. Measurements on partially recrystallized samples using a monochromatic high-energy synchrotron beam show that recrystallized grains generate sharp diffraction spots, whereas the intensity from the deformed matrix varies smoothly along the Debye–Scherrer rings. Based on these observations, a method has been developed to separate the recrystallization texture components from those originating from the deformation matrix. The validity of this method is demonstrated with partially recrystallized interstitial-free steel.

Characterization, in the language of synchrotron radiation, was performed on a GE Revolution 41RT flat panel detector using the X-ray light source at the Advanced Photon Source (APS). The detector has an active area of 41 x 41 cm{sup 2} with 200 x 200 {micro}m{sup 2} pixel size. The nominal working photon energy is around 80 keV. Modulation transfer function (MTF) was measured in terms of line spread function (LSF) using a 25 {micro}m x 1 cm tungsten slit. Memory effects of the detector elements, called lag, were also measured. The large area and fast data capturing rate - 8 fps in unbinned mode, 30 fps in binned or region of interest (ROI) mode - make the GE flat panel detector a unique and very versatile detector for synchrotron experiments. In particular, we present data from pair distribution function (PDF) measurements to demonstrate the special features of this detector.

We have fabricated and characterized the performance of a monolithic Ge Bragg–Laue phase retarder capable of simultaneously producing both right- and left-handed circularly polarized x rays. The energy range of operation of the phase retarder is between 50 and 100 keV making it well suited to the measurement of spin-dependent Compton profiles within the impulse approximation, primarily because of the increased momentum resolution and larger Compton scattering cross section available at these higher incident energies. Although the phase retarder was optimized for operation at 86 keV, it can produce highly circularly polarized x rays over a substantial energy range. The performance of the phase retarder was tested via magnetic Compton scattering measurements on an Fe sample at the undulator A of the Advanced Photon Source. It was found to perform well in terms of flux and degree of circular polarization thereby greatly reducing the data collection times required for this inherently weak scattering process.

Hard x-ray absorption spectroscopy is combined with scanning microtomography to reconstruct full near-edge spectra of an elemental species at each location on an arbitrary virtual section through a sample. These spectra reveal the local concentrations of different chemical compounds of the absorbing element inside the sample and give insight into the oxidation state, the local atomic structure, and the local projected free density of states. The method is implemented by combining a quick scanning monochromator and data acquisition system with a scanning microprobe setup based on refractive x-ray lenses.

We have constructed an X-ray phase plate to produce linearly and circularly polarized X-rays at discrete energies between 20 keV and 88 keV. The plate is a monolithic two-crystal design, constructed from germanium. We have measured the degree of circular polarization at 65 keV to be 90%±4%, which is significantly better than that produced by silicon phase plates. This radiation was used to measure the magnetic Compton profile for Fe, which was found to be in good agreement with theory and previous work. The underlying X-ray optics and the characterization of the device between 62 keV and 93 keV at the Cornell High Energy Synchrotron Source are presented.

Over the last five years, based on the operating experiences, many upgrades have been made to the beamline standard components to continue improving beamline performance and reliability at the Advanced Photon Source (APS). In this article, the particular design upgrades, as well as the new component design specifications of APS beamline standard components, are summarized.

Real-time evolution of nanoparticles grown at the semiconductor/electrolyte interface formed between a single crystalline n-type GaAs wafer and an aqueous solution of AgNO(3) has been studied by using high-energy synchrotron X-ray diffraction. The results reveal the distinct nucleation and growth steps involved in the growth of anisotropic Ag nanoplates on the surface of the GaAs wafer. For the first time, a quick transit stage is observed to be responsible for the structural transformation of the nuclei to form structurally stable seeds that are critical for guiding their anisotropic growth into nanoplates. Reaction between a GaAs wafer and AgNO(3) solution at room temperature primarily produces Ag nanoplates on the surface of the GaAs wafer in the dark and at room temperature. In contrast, X-ray irradiation can induce charge separation in the GaAs wafer to drive the growth of nanoparticles made of silver oxy salt (Ag(7)NO(11)) and silver arsenate (Ag(3)AsO(4)) at the semiconductor/electrolyte interface if the GaAs wafer is illuminated by the X-ray and reaction time is long enough.

The considerable intensity of Advanced Photon Source (APS) undulator A as a source of high-energy X-rays permits the performance of numerous types of experiments that require such photon energies. Measured and calculated properties, in the 50-200 keV range, of the X-ray beam from undulator A, installed in sector 1 of the APS, are presented. The flux spectra observed at various gaps agree well with calculations that incorporate the actual magnetic field within the device and the emittance and energy spread of the stored positrons. The field errors and energy spread cause the X-ray beam to lose undulator radiation properties at high energies, as seen in the smeared-out spectral harmonics and increased beam divergence, giving resemblance to a low-K wiggler source. Owing to the wiggler-like behavior in this photon-energy range, the optimal operating condition for undulator A is in the vicinity of the closed-gap setting, corresponding to a maximum critical energy.

Hard x-ray absorption spectroscopy is combined with scanning microtomography to reconstruct full near edge spectra of an elemental species at each location on an arbitrary virtual section through a sample. These spectra reveal the local concentrations of different chemical compounds of the absorbing element inside the sample and give insight into the oxidation state, the local atomic structure, and the local projected free density of states. The method is implemented by combining a quick scanning monochromator and data acquisition system with a scanning microprobe setup based on refractive x-ray lenses. The full XANES spectra reconstructed at each point of the tomographic slice allow to detect slight variations in concentrations of chemical compounds, such as metallic and monovalent copper. The method is applied to the analysis of a heterogeneous catalyst.

Interpenetrating Al2O3/Al composites were created by liquid-metal infiltration of alumina preforms with three-dimensional periodicity produced by a robotic deposition method. Volume-averaged lattice strains in the alumina phase were measured by synchrotron x-ray diffraction at various uniaxial compression stresses up to 350 MPa. Load transfer, which is experimentally found to occur between the aluminum and the alumina phase, is in agreement with simple rule of mixtures models. Spatially resolved measurements showed variations in load transfer at different positions within the composite for the elastic-, plastic-, and damage-deformation regimes. Using phase-enhanced imaging, the extent of damage within the composites was observed.

A set of precision horizontal and vertical white‐beam slits has been designed for the Advanced Photon Source x‐ray undulator beamlines at Argonne National Laboratory. There are several new design concepts applied in this slit set, including a grazing‐incidence knife‐edge configuration to minimize the scattering of x rays downstream, enhanced heat transfer tubing to provide water cooling, and a secondary slit to eliminate the thermal distortion on the slit knife edge. The novel aspect of this design is the use of two L‐shaped knife‐edge assemblies, which are manipulated by two precision X‐Z stepping linear actuators. The principal and structural details of the design for this slit set are presented in this paper.

We have used a new approach involving simultaneous diffraction and small angle scattering to study the amorphous-to-crystalline phase transformation in Zr-based bulk metallic glass. In situ, time-resolved data provided the first direct demonstration of a phase separation prior to crystallization. There is evidence that nucleation and growth of the crystalline phase occur in separate stages, with different kinetics. Our data support the view that crystalline nucleation is achieved via short-range diffusion of small atoms (e.g., Ni), whereas the growth is dictated by long-range diffusion.

This paper reports on experiments in which high-energy (65.35 keV) X-rays were used to record the detailed diffuse diffraction patterns of a number of ceramic materials. The methodology has enabled a greater q-range to be explored (up to sintheta/lambda approximately 0.97) than is possible with laboratory-based experiments, with better q-space resolution and increased sensitivity, thus allowing previously unseen detail in diffraction patterns to be recorded. In all, 11 sections of data have been collected for Ca-CSZ, eight for Y-CSZ and six for wuestite.

A compact tube furnace has been developed for high temperature X-ray diffraction studies using high energy synchrotron radiation. The furnace design has a low absorption path in transmission yet allows for a high degree of control of the sample atmosphere and a minimal temperature gradient across the sample. The design allows for a maximum temperature of 1500°C with a variety of atmospheres including inert, reducing, and oxidizing. Preliminary results obtained at the SRI-CAT I-ID undulator line (60keV) at the APS facility and the A2 24 pole wiggler line (45keV) at CHESS on the Ti5Si3Z5 (Z = C, N, O) system will be presented to demonstrate the feasibility of this approach.

At the Advanced Photon Source (APS), each insertion-device (ID) beamline front end has two X-ray beam position monitors (XBPMs) to monitor the X-ray beam position for both vertical and horizontal directions. Performance challenges for a conventional photoemission-type XBPM during operations are contamination of the signal from the neighbouring bending-magnet sources and the sensitivity of the XBPM to the insertion-device gap variations. Problems are exacerbated because users change the ID gap during their operations, and hence the percentage level of the contamination in the front-end XBPM signals varies. A smart XBPM system with a high-speed digital signal processor has been built at the Advanced Photon Source for the ID beamline front ends. The new version of the software, which uses an artificial-intelligence method, provides a self-learning and self-calibration capability to the smart XBPM system. The structure of and recent test results with the system are presented in this paper.

The inclined double crystal monochromator arrangement is very effective in handling high heat loads and holds considerable promise as a monochromator for undulator beams at third generation synchrotrons. Results for the ideal inclined crystal case have been obtained by dynamical diffraction calculations, and diffraction results for the (111) reflection of silicon are presented for an inclination angle of 85{degree}0 and energies of 5 key and 13.84 key. The diffraction characteristics resemble closely diffraction from-asymmetric (111) plane of silicon. However, the inclined and noninclined cases are not identical. Diffraction in the inclined case is slightly different due to refraction. The full width at half maximum of the Darwin-Prins reflectivity curve is slightly increased ({approximately}l%), and the angles of the outgoing beam after one reflection are slightly altered. That is, except for a wave incident at the Laue point in reciprocal space, the diffraction is always slightly asymmetric. The effect can be exactly reversed by an identical second crystal in the (+,{minus}) arrangement.

The inclined double crystal monochromator arrangement is very effective in handling high heat loads and holds considerable promise as a monochromator for undulator beams at third generation synchrotrons. Results for the ideal inclined crystal case have been obtained by dynamical diffraction calculations, and diffraction results for the (111) reflection of silicon are presented for an inclination angle of 85{degrees} and energies of 5 keV and 13.84 keV. The diffraction characteristics resemble closely diffraction from a symmetric (111) plane of silicon. However, the inclined and noninclined cases are not identical. Diffraction in the inclined case is slightly different due to refraction. The full width at half maximum of the Darwin-Prins reflectivity curve is slightly increased ({approximately} 1%), and the angles of the outgoing beam after one reflection are slightly altered. That is, except for a wave incident at the Laue point in reciprocal space, the diffraction is always slightly asymmetric. The effect can be exactly reversed by an identical second crystal in the (+,-) arrangement.

Hard x-ray absorption spectroscopy is combined with scanning microtomography to reconstruct full near edge spectra of an elemental species at each point on an arbitrary virtual section through a sample. These spectra reveal the local concentration of different chemical compounds of the absorbing element inside the sample and give insight into the oxidation state and the local projected free density of states. The method is implemented by combining a quick scanning monochromator and data acquisition system with a scanning microprobe setup based on refractive x-ray lenses. The full XANES spectra reconstructed at each point of the tomographic slice allow one to detect slight variations in concentration of the chemical compounds, such as Cu and Cu(I)2O.

Since high‐energy photons (≳50 keV) are well suited for certain types of x‐ray scattering experiments, we present calculated results for the Advanced Photon Source (APS) Undulator A and APS Wiggler A at high energies. The undulator calculations include the effect of magnetic field errors, which is to smear the high‐order spectral harmonics. At their anticipated initial minimum gap settings, Undulator A should perform better than Wiggler A from the point of view of most high energy experiments up to at least ∼280 keV. A comparison of APS insertion devices to high energy insertion devices in other synchrotron radiation laboratories is also provided.

Three high-energy optics accomplishments are presented. The first is a cryogenically cooled, bent, double-Laue monochromator for 50–200 keV x rays, which delivers over ten times more flux than that from a flat crystal monochromator, but without an increase in energy width. Second, the microfocusing of 50 keV undulator radiation using two stacked Fresnel zone plates is described. Third, a high-resolution inverse-Cauchois scanning analyzer, consisting of a bent Laue crystal, is presented for Compton and fluorescence spectroscopy applications.

The first undulator radiation has been extracted from the Advanced Photon Source (APS). The results from the characterization of this radiation are very satisfactory. With the undulator set at a gap of 15.8 mm (K=1.61), harmonics as high as the 17th were observed using a crystal spectrometer. The angular distribution of the third-harmonic radiation was measured, and the source was imaged using a zone plate to determine the particle beam emittance. The horizontal beam emittance was found to be 6.9 {plus_minus} 1.0 nm-rad, and the vertical emittance coupling was found to be less than 3%. The absolute spectral flux was measured over a wide range of photon energies, and it agrees remarkably well with the theoretical calculations based on the measured undulator magnetic field profile and the measured beam emittance. These results indicate that both the emittance of the electron beam and the undulator magnetic field quality exceed the original specifications.