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The design and operation of a new small‐angle X‐ray scattering instrument, optimized for high throughput at a synchrotron source, high angular and wavelength resolution, large sample cross‐sectional area, accurate energy tuning, excellent signal‐to‐noise ratio and harmonic rejection are presented. The principles of design and implementation are given, as are the details of primary calibration of absolute intensity and experimental desmearing. The instrument has been tested for application to anomalous‐scattering measurements near the chromium K edge. Preliminary results on samples of a heat‐treated steel are presented as a demonstration of the capability of this experiment to separate the microstructure evolution as a function of temperature of a chromium‐rich precipitate from the thermal behavior of other precipitates in the steel.

A high-performance magnetic shield with large length-to-diameter ratio Rev. Sci. Instrum. 83, 065108 (2012) Radiation and near field in resistance-inductor circuit transients J. Appl. Phys. 111, 114907 (2012) Loss characterization of Mo-doped FeNi flake for DC-to-DC converter and MHz frequency applications J. Appl. Phys. 111, 07E329 (2012) The electron cyclotron resonance ion source with arc-shaped coils concept (invited) Rev. Sci. Instrum. 83, 02A312 (2012) Additional information on J. Appl. Phys.Calculations are reported for the spatial distribution of magnetic fields in the neighborhood of a long surface crack in a conductor, where a uniform ac magnetic field is applied parallel to the length of the crack. The problem is resolved into tractable parts consisting of the cases of eddy currents near a semiinfinite crack with a sharp tip and eddy currents near a square comer. The semi-infinite crack problem is solved exactly by a modification of Sommerfeld's diffraction theory and the comer problem is treated by a Green's function obtained by the method of images. The composite solution is valid for a crack of depth equal to four times the electromagnetic skin depth or greater. From the solution, the Poynting vector is calculated and its integral over the surface computed. The change in power dissipation relative to the "uncracked" surface is given in a simple form.

The asymmetric Bragg diffraction microscope is a novel x-ray microscope which forms a magnified in-line near-field hologram by asymmetric reflection from two crossed flat crystals. In this paper, the optics of the microscope is studied theoretically. The optical transfer function is obtained, and the limiting spatial resolution, rated at 25% modulation transfer, is determined to be 0.30 microm at an optimum magnification of 89x with Si crystals, over a wide range of hard x-ray wavelengths. Absorption and phase contrast images can be computed from holograms acquired at several object distances. Application to submicrometer resolution hard x-ray microtomography is envisioned.

A high-resolution hard x-ray microscope is described. This system is capable of detecting line features as small as 0.6 µm in width, and resolving line pairs 1.2-µm wide and 1.2-µm apart. Three types of two-dimensional image detectors are discussed and compared for use with hard x rays in high resolution. Principles of x-ray image magnification are discussed based on x-ray optics and diffraction physics. Examples of applications are shown in microradiography with fiber reinforced composite materials (SiC in Ti3Al Nb) and in diffraction imaging (topography) with device patterns on a silicon single crystal. High-resolution tomography has now become a reality.