New opportunities in biological and chemical crystallography

This article, now updated, was originally published in Indian J. Phys. [(2001), A84, 1–11] which in turn was based on the Professor K. Banerjee Birth Centennial Medal lecture of the author given in Calcutta in September 2000.

A multiple-scattering theory of circular and linear dichroism for photoemission and photoabsorption

A unfied approach is presented for calculating magnetic and natural dichroism (both circular and linear) in (spin-resolved) photoemission and absorption, valid in the many-body case and for extended systems. The reduction of this scheme to the independent particle approach describes these spectroscopies within the framework of multiple-scattering theory.

Measuring wavelengths and lattice constants with the Mössbauer wavelength standard

The ⁵⁷Fe Mössbauer wavelength standard is used to measure the lattice constants of Al₂O₃, as well as the wavelengths of the ¹⁵¹Eu, ¹¹⁹Sn and ¹⁶¹Dy Mössbauer radiation.

Multiple-order reflections from monochromating crystals for the collection of X-ray absorption spectra at extremely high energies

Extended X-ray absorption fine structure experiments can be performed at extremely high energies (>50 keV) by using multiple-order reflections from the monochromator. Examples show that, notwithstanding the considerable core-hole broadening of the spectra, quantitative data can be extracted both from bulk and diluted samples.

Energy-selective (+, +) monolithic monochromator and relative lattice-spacing measurement of Si wafers with synchrotron radiation

Since synchrotron radiation has no characteristic (wavelength) spectral lines, a (+, +) high-resolution channel-cut monolithic monochromator has been introduced as an energy-selective device for the study of the lattice spacing of single crystals. Using two types of monolithic monochromator, two systems are proposed and applied to the high-precision measurement of the lattice spacing of Si wafers. The system can be applied for a fast and precise measurement of the lattice-spacing changes due to the doping in Si, GaAs and other single crystals.

High-sensitivity CCD-based X-ray detector

The 49 × 86 mm 28 Mpixel detector discriminates single X-ray photons, has a large dynamic range, and a computer-controlled readout system that allows multiple pixel binning schemes and flexible operation in time-resolved experiments.

Design and performance of ESRF high-power undulator front-end components

Compact high-power absorbers and diamond windows have been tested and installed on undulator-based ESRF front ends. The absorber has been tested at a peak power density of 1200 W mm⁻² at normal incidence.

APS gets funding for new beamlines for structural biology

SSRL and Daresbury enter into a Memorandum of Understanding

Technical Director for DIAMOND appointed

John Helliwell becomes CCLRC's Director of Synchrotron Radiation Science based at Daresbury

Francesco Sette takes over from Christof Kunz

Roger Fourme becomes Life Science Director for SOLEIL

APS gets a new head

Notes for Authors

Forthcoming meetings and short courses