July 2000 issue
The effect of the surface roughness of optical elements, such as Be windows and reflection mirrors, in synchrotron radiation beamlines on the spatial coherence of the X-ray beam is investigated systematically by means of digital simulation, in which a new model for X-ray reflection from a rough surface is proposed.
The efficiency of Y3Al5O12:Ce phosphor powder screens in the VUV and soft X-ray regions is reported. Also, a custom-built camera for making measurements in forward and backward modes is described.
A prototype X-ray detector, based on silicon microstrip technology, has been developed for energy-dispersive EXAFS studies and tested at the UK Synchrotron Radiation Source (SRS).
Instrumentation for time-resolved diffraction studies of transient photoinduced species is described. Equations are given for the maximum and average fractional excited-state populations as a function of lifetime, pulse frequency and efficiency of excitation.
Wavelength normalization of Laue X-ray diffraction data obtained using insertion devices is presented. Reproducibility and accuracy of the data-derived spectra are discussed for sources with complex spectra, such as wiggler/undulator tandems and single-line undulators.
A microdeformation device has been constructed and used to collect force/strain and micro-SAXS data in real time from single struts of an elastomeric polyurethane foam.
A total of 40 high-quality powder patterns on a manganate perovskite (Nd0.43Sr0.57MnO3) in the temperature range 105–200 K were obtained in less than 2 h by making use of synchrotron radiation and an area detector equipped with online readout capabilities. The data made possible a detailed study of the temperature dependence of the structural changes taking place in this material.
An experimental facility for combined high-pressure EXAFS, X-ray diffraction and photoluminescence is described.
How to use the classical statistical tools to estimate statistical errors on EXAFS and its Fourier transform.
B12 cofactors can be photoreduced by X-rays when their cobalt centre is coordinated by an inorganic ligand (water or cyanide), but not when it carries an organometallic `upper' ligand. This could be demonstrated by X-ray absorption spectroscopy.
A new experimental technique for reciprocal X-ray holography has been developed. The experimental set-up makes it possible to measure a reciprocal hologram without unwanted mixture of the X-ray fluorescence holography signal.
A large monolithic X-ray interferometer having a view size of width 25 mm and height 15 mm has been fabricated to observe large objects in phase-contrast X-ray imaging.
A computer program for X-ray absorption spectroscopic data acquisition is described, including the program architecture, basic operation and graphical user interface.