An X-ray scattering beam line at the national synchrotron light source

Abstract

An X-ray beam line for chemical crystallography and scattering research is under construction at the National Synchrotron Light Source (Brookhaven National Laboratory). The X-ray beam is designed to be tunable in the energy region 4 to 21 keV ( λ = 0.6−3.1 A ̊ ) with an energy resolution ( ΔE/ E) of 5 × 10 −4. The intensity will be uniform to better than 1% over an area of 0.3 ×10.3 mm 2 at the sample position. The beam optics will consist of two mirrors: one spherical and one bent cylinder approximating an ellipsoid, as well as a fixed exit double-crystal (Si) monochromator. The line will be instrumental with a four-circle goniostat (Huber) designed to work in both vertical and horizontal modes. The chi-circle has an inner diameter of 40 cm and an offset phi-axis to allow the use of a variety of sample chambers such as high- or low-temperature devices. The diffractometer will be controlled by a PDP-11/23 microcomputer operating under RSX-11M. The beam line initially will be outfitted with a single-channel detector. Equipment will also include a rotation camera for extensive data collections on macromolecules using film as a detection medium. The beam line is designed and built jointly by a Participating Research Team and the National Synchrotron Light Source Facility and is expected to commence regular experimental research, after an initial start-up period, during the first half of 1982.