MX1 is a bending-magnet crystallography beamline at the 3 GeV Australian Synchrotron. The beamline delivers hard X-rays in the energy range from 8 to 18 keV to a focal spot at the sample position of 120 mm FWHM. The beamline endstation and ancillary equipment facilitate local and remote access for both chemical and biological macromolecular crystallography. Here, the design of the beamline and endstation are discussed. The beamline has enjoyed a full user program for the last seven years and scientific highlights from the user program are also presented.

A microfocus macromolecular crystallography beamline at the Australian Synchrotron is presented.

Abstract. We present herein the current status of the X-ray Absorption Spectroscopy (XAS) Beamline at the 3 GeV Australian Synchrotron. The optical design and performance, details of the insertion device (Wiggler), end station capabilities and construction and commissioning timeline are given.

The amount fraction of oxygen in oxygen–nitrogen gas mixtures has been measured with a relative uncertainty of ±0.02% within the range 100–1000 mmol mol−1. The method employed uses an auto-null ‘dumbbell’ type paramagnetic oxygen sensor, which has high resolution (10 µmol mol−1) and excellent linearity. The sensor is used to compare the sample gas mixture with pure oxygen and nitrogen gases, which compensates for drift and pressure change, and avoids the uncertainty from using bottled calibration gas mixtures. The method was verified by measuring primary standard gas mixtures at the National Physical Laboratory. To the authors knowledge the uncertainty achieved is better than any other analytical instrument, within the specified range.