issue contents
September 2016 issue
facility information
feature articles
Free
The vast majority of biomolecular processes are controlled by the bound water and there is no direct method to address the important biological problems associated with protein–water interactions. In this article, the progress that has been made in synchrotron-based radiolytic labeling and mass spectroscopy techniques for both the identification of bound waters and for characterizing the role of water in protein conformational changes at a high degree of spatial and temporal resolution are summarized.
research papers
The first simultaneous lasing of three different free-electron lasers driven by the same superconducting linear accelerator at FLASH at DESY is presented.
Open access
The 25 nrad RMS, 1–2500 Hz, vibrational performance of a horizontal double-crystal monochromator is presented.
The performance of a cooled Be compound refractive lens has been tested at the Advanced Photon Source to enable vertical focusing of the pink beam and permit the X-ray beam to spatially overlap with an 80 µm-high low-density plasma that simulates astrophysical environments.
The traditional figuring model, which is based on height profiles, is problematic in the cases wherein slope profiles are applied. Therefore, an advanced figuring model based directly on slope profiles is proposed.
A new kind of prism-array lens for high-energy X-ray focusing is designed, fabricated by LIGA technology and measured using the knife-scan method.
A theoretical and experimental investigation of the effect of angular vibrations of a double-crystal monochromator on the X-ray beam quality is presented.
A 30-lens interferometer was designed, manufactured and tested at X-ray energies from 30 to 65 keV. The interferometer was used to measure an effective source (FWHM) of 15 µm from the interference pattern recorded at the fundamental Talbot distance.
A novel in situ high-speed X-ray atomic force microscope was used in situ in normal-incidence X-ray experiments to characterize radiation damage on semiconducting organic thin films. Local morphological damage occurring at specific timescales was observed and compared with the corresponding variation of the diffraction patterns.
Fabrication and results of high-resolution X-ray topography characterization of diamond single-crystal plates with large surface area (10 mm × 10 mm) and (111) crystal surface orientation for applications in high-heat-load X-ray crystal optics are reported.
A new optical layout adapted to large vacuum-ultraviolet bending-magnet synchrotron beamline extractions is proposed, which provides intense and aberration-free vacuum-ultraviolet radiation beams.
Open access
A portable device, using the speckle scanning technique, has been developed for in situ metrology of X-ray mirrors at synchrotron light facilities.
The first commercially sold compact light source has been installed in Munich, Germany; here information on the performance of the machine, such as produced flux, source sizes and spectra, is provided.
Open access
The SwissFEL Experimental Laser facility and its integration with experimental stations are presented. The main aspects are reliability and performance to meet the versatile requirements from operations and users.
In both step- and fly-scanning modes, robust, simultaneous XFM–SXDM (X-ray fluorescence microscopy–scanning X-ray diffraction microscopy) at the Australian Synchrotron XFM beamline is demonstrated. Using the fast-scanning Maia detector system, robust, event-mode SXDM data organization allows rapid imaging of large samples to be routine.
Electron spectroscopy in laser-pump/X-ray probe experiments is used to characterize electron dynamics, with an emphasis on space-charge acceleration.
A prototype unit of the ePix100 camera was used for coherent scattering studies at the Linac Coherent Light Source. The performance of the detector was tested over a broad range of incident flux from 23 down to 0.01 photons per pixel on average.
The ability of a high-resolution silicon-based single strip detector to perform pre-treatment quality control in microbeam radiation therapy is investigated. The study is based on in-air measurements of energy deposition in silicon by arrays of microbeams. Special attention was dedicated to the detection of the multi-slit collimator misalignment, the device in charge of the spatial fractionation of the primary beam into an array of microbeams.
Combined use of a synchrotron X-ray microbeam-irradiated three-dimensional reactive oxygen species gel and confocal laser scanning fluorescence microscopy provides a simple dosimetry method for track analysis of X-ray photoelectric nanoradiator radiation, suggesting extensive cellular damage with dose-enhancement beyond a single cell containing Fe3O4 nanoparticles.
Using the dual-energy K-edge subtraction technique it was possible to observe nanoparticles inside insects (mealworm beetles).
A comparative study using experimental data from grating-based interferometry and propagation-based phase contrast combined with single-distance phase retrieval applied to a non-homogeneous sample is presented.
Open access
The performance of a diamond X-ray phase retarder to enable the production of circularly polarized X-rays has been quantitatively measured and magnetic dichroism contrast in transmission and diffraction geometries has been demonstrated. Feasibility tests for dichroic Bragg coherent diffractive imaging experiments were performed and showed that the diamond X-ray phase retarder does not produce significant distortions to the X-ray wavefront and that Bragg coherent diffractive imaging reconstructions are achievable.
A robust end-point constraint used in thinning to generate a geometry-preserving skeleton to improve the precision of the quantitative assessment of micro-vasculature acquired from synchrotron-based X-ray computed micro-tomography is proposed
Radiation from a tokamak applicable for runaway electrons diagnosis has been proposed.
short communications
In-vacuum grating angles calibration with a digital autocollimator.
An intensity summation method for correction of runout errors of the rotation stage in computed tomography is presented.
The possibility of using both polychromatic and monochromatic hard X-rays to facilitate 3D Bragg coherent diffraction imaging experiments of individual crystallites from a textured population is explored. Approaches to measure 3D Bragg peaks without moving the sample via monochromatic energy scanning and by pink beam diffraction analyzers are presented.
beamlines
Open access
A beamline is described for grazing-incidence X-ray diffraction at Diamond Light Source that houses two experimental hutches, the first housing a large multi-circle diffractometer on which a wide variety of sample environments can be mounted and the second with an ultrahigh-vacuum system on the diffractometer to enable in situ studies of molecular beam epitaxy. Techniques available include X-ray reflectivity, surface X-ray diffraction, grazing-incidence small-angle X-ray scattering, grazing-incidence wide-angle X-ray scattering and grazing-incidence diffraction.
computer programs
A flexible experiment workflow system based on high-throughput data acquisition and processsing for feedback-driven and online imaging experiments is presented.
Open access
CTM4DOC, a new graphical user interface for electronic structure calculations in X-ray spectroscopy, is introduced and examples in transition metal complexes are described.
addenda and errata
Free
Formulae in the paper by Balyan (2015) [J. Synchrotron Rad. 22, 1410–1418] are corrected.