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The RAPID2 detector readout system that is successfully deployed for MWPC detectors is tested on a prototype 1-D Gas MicroStrip Detector (GMSD). Reference interpolation results from the 2-D RAPID2 micro-gap MWPC recently installed at SPRing-8 are used for comparison. Good agreement is obtained in these initial tests. This paves the way towards the goal of incorporating the RAPID2 readout to a hybrid 2-D multi-wired GMSD that is undergoing the design stage.

The significant degree of X-ray phase contrast created by air-tissue interfaces, coupled with the poor radiographic contrast of conventional chest radiographs, makes the inflated lung an ideal candidate for investigating the potential diagnostic improvement afforded by phase contrast X-ray imaging. In small animals these methods highlight the lung airways and lobe boundaries and reveal the lung tissue as a speckled intensity pattern not seen in other soft tissues. We have compared analyser-based and propagation-based phase contrast imaging modalities, together with conventional radiographic imaging, to ascertain which technique shows the greatest image enhancement for various lung sizes. The conventional radiographic image of a mouse was obtained on a Siemens Nova 3000 mammography system, whilst phase contrast images of mice and rabbit chests were acquired at the medical imaging beamline (20B2) at the SPring-8 synchrotron radiation research facility in Japan. For mice aged 1 day, 1 week and 1 month old it was determined that analyser-based imaging showed the greatest overall image contrast, however, for an adult rabbit both techniques yielded excellent contrast. The success of these methods in creating high quality images for rabbit lungs raises the possibility of improving human lung imaging using phase contrast techniques.

The Diffraction-Enhanced Imaging (DEI) system, which shares access to Beamline 7.6 on the Daresbury Synchrotron Radiation Source (SRS), is now in its third year of existence. The system was developed under a European Commission grant PHase Analyser SYstem (PHASY), won during the Fourth Framework. Typical applications continue to be the imaging of small biological specimens, using a beam of 12–17 keV after monochromation and up to 40 mm in width and 1–2 mm in height, although it is planned to investigate other materials as opportunity permits and time becomes available for more routine scientific use. Recent improvements have been made to the optical alignment procedure for setting up the station before imaging: a small laser device can now be set up to send a beam down the X-ray path through the four crystals, and a small photodiode, which has much better signal-to-noise characteristics than the ion chamber normally used for alignment, has been trailed successfully. A 3-D tomographic reconstruction capability has recently been developed and tested for DEI projection image sets, and will be applied to future imaging work on the SRS, in conjunction with volume visualization software. The next generation of DEI system, planned to operate at up to 60 keV on an SRS wiggler station, is in its design stage; it will feature much improved mechanics and mountings, especially for angular control, and a simplified alignment procedure to facilitate the necessary sharing of the SRS station.

A new enhancement method in medical imaging is required for differentiating soft biological tissues of very similar absorption strengths. Breast cancer screening and studies in articular cartilage are two examples where this is encountered. X-ray refraction in association with highly angular sensitive diffraction optics and a highly collimated synchrotron light source are identified to provide one possible answer. Demonstrative images taken with the new X-ray diffraction enhanced imaging camera on the UK synchrotron light source, SRS at Daresbury Laboratory, are showing encouraging results.

Three-dimensional information is obtained for the Cu site in azurin at very high resolution by combining high-resolution crystallographic structures and EXAFS data for the oxidized and reduced form of the protein. This combined approach has allowed us to define the subtle structural changes (

In a recent preliminary experiment, a test phantom was imaged using Diffraction Enhanced Imaging (DEI). DEI is a synchrotron-based radiographic imaging technique which uses a single energy of X-rays and the fine angular acceptance of Bragg diffraction to separate out the components of the X-ray beam that have undergone different interactions within the sample. The test phantom was imaged using a beam with energy of 14 keV. The techniques used in this experiment meant that two sets of images were produced of the phantom. The first set is composed of refraction and apparent absorption images. The second technique produced an additional ultrasmall angle scattering image. The use of this second method gave more information than the first technique by showing the scattering properties of the phantom components, we intend to study this feature further in future experiments.

The aim of this experiment was to produce X-ray images of mice feet using the diffraction-enhanced imaging (DEI) system at the UK Synchrotron Radiation Source (SRS) at Daresbury. There were two broad types of mice feet samples studied: normal and arthritic. The two types of samples were imaged using several views and compared in order to determine whether it would be possible to detect the early morphological changes linked with this form of arthritis. We found that the DEI images produced were indeed of sufficient quality to show the presence of some osteoarthritic changes.

The problems inherent in the fabrication of short period multilayer mirrors are discussed and results of the synthesis of multilayer structures with nanometer period are presented. The shortest period observed is 13 A for WSi and WB 4 C sputtered multilayers. Measurements of near normal incidence reflectivity at λ = 31–32A are presented for WSc multilayers with a period approximately 16 A. The measured reflectivity reaches a maximum of 3.3% and is in good agreement with theoretical modeling after the inclusion of interfacial roughness.

Diffraction Enhanced Imaging (DEI) is an x-ray phase contrast technique, which is showing great promise for a number of medical imaging problems. For a source it relies on a highly collimated flux of monochromatic x-rays, which is currently only available at synchrotron radiation facilities. Phase shifts occurring as the wave passes through the object are made visible using Bragg diffraction from a post-sample analyser optic. In early 2004 the DEI system on the bending-magnet beam line 7.6 of the Daresbury SRS was used for the first time to image a number of small medical specimens. This paper will report on the performance of the system and the results of these initial studies. A new DEI instrument is currently in the design phase. This facility will be integrated on wiggler station 9.4 on the SRS allowing access to shorter x-ray wavelengths and greater flux. A progress report on the design features and implementation of this system will be given.

Station 7.1 was the first XAFS station to operate at the Synchrotron Radiation Source (SRS) starting in 1981. A major upgrade of 7.1 has been taking place aimed towards a multidimensional XAFS and single crystal facility for 3d elements (Ca to Zn). The optical upgrade included a collimating mirror and QuEXAFS monochromator, also a highly compact and rapid count-rate multi-element solid state detector has been designed, built and recently commissioned. A stopped-flow system is commissioned and a diffractometer stage is planned. The necessary analytical tools for 3D XAFS refinement using crystallographic data as the starting 3D model have been developed for solution XAFS.

A highly compact and rapid-count-rate multi-element solid-state detector has been designed, built and recently commissioned on the oldest XAFS station of the SRS, station 7.1, which has undergone major refurbishment. The low profile of the detector has been achieved by using the monolithic solution where nine elements with a combined active area of 370 mm2 have been fabricated on Ge of diameter 21.8 mm. A typical energy resolution of 170 eV with a semi-Gaussian shaping time of 0.5 µs has been achieved with X-rays of energy 5.9 keV. The low profile of the detector makes it ideal for several synchrotron radiation applications as it can be easily incorporated into complicated experimental set-ups. These include XAFS of single crystals and samples generated in a stopped flow system, protein crystallography (fluorescence XAFS for MAD or for on-line monitoring), microprobe fluorescence imaging and trace-element analysis.

We report on a study of grazing incidence absorption and reflection spectra of NiO in the region of the Ni 2p edge. The aim is to evaluate the distortion of the near edge spectrum by the critical angle behavior of individual components within the spectrum. This can be used to improve the separation of multiplets and enhance low spectral weight line shapes like charge transfer satellites. The measured spectra have been compared with calculations using an optical model.