Energy spectra considerations for synchrotron radiotherapy trials on the ID17 bio-medical beamline at the European Synchrotron Radiation Facility
The aim of this study was to validate the kilovoltage X-ray energy spectrum on the ID17 beamline at the European Synchrotron Radiation Facility (ESRF). The purpose of such validation was to provide an accurate energy spectrum as the input to a computerized treatment planning system, which will be used in synchrotron microbeam radiotherapy trials at the ESRF. Calculated and measured energy spectra on ID17 have been reported previously but recent additions and safety modifications to the beamline for veterinary trials warranted a fresh investigation. The authors used an established methodology to compare X-ray attenuation me...
Source: Journal of Synchrotron Radiation - June 26, 2015 Category: Physics Authors: Crosbie, J.C.Fournier, P.Bartzsch, S.Donzelli, M.Cornelius, I.Stevenson, A.W.Requardt, H.Bräuer-Krisch, E. Tags: synchrotron radiotherapy energy spectra treatment planning research papers Source Type: research

MISTRAL: a transmission soft X-ray microscopy beamline for cryo nano-tomography of biological samples and magnetic domains imaging
The performance of MISTRAL is reported, the soft X-ray transmission microscopy beamline at the ALBA light source (Barcelona, Spain) which is primarily dedicated to cryo soft X-ray tomography (cryo-SXT) for three-dimensional visualization of whole unstained cells at spatial resolutions down to 30 nm (half pitch). Short acquisition times allowing for high-throughput and correlative microscopy studies have promoted cryo-SXT as an emerging cellular imaging tool for structural cell biologists bridging the gap between optical and electron microscopy. In addition, the beamline offers the possibility of imaging magnetic domains ...
Source: Journal of Synchrotron Radiation - June 25, 2015 Category: Physics Authors: Sorrentino, A.Nicolás, J.Valcárcel, R.Chichón, F.J.Rosanes, M.Avila, J.Tkachuk, A.Irwin, J.Ferrer, S.Pereiro, E. Tags: X-ray microscopy tomography correlative imaging magnetic domains imaging beamlines Source Type: research

A phase-space beam position monitor for synchrotron radiation
The stability of the photon beam position on synchrotron beamlines is critical for most if not all synchrotron radiation experiments. The position of the beam at the experiment or optical element location is set by the position and angle of the electron beam source as it traverses the magnetic field of the bend-magnet or insertion device. Thus an ideal photon beam monitor would be able to simultaneously measure the photon beam's position and angle, and thus infer the electron beam's position in phase space. X-ray diffraction is commonly used to prepare monochromatic beams on X-ray beamlines usually in the form of a double-...
Source: Journal of Synchrotron Radiation - June 25, 2015 Category: Physics Authors: Samadi, N.Bassey, B.Martinson, M.Belev, G.Dallin, L.de Jong, M.Chapman, D. Tags: beam position monitor X-ray diffraction K-edge absorption phase space research papers Source Type: research

Development of variable-magnification X-ray Bragg optics
A novel X-ray Bragg optics is proposed for variable-magnification of an X-ray beam. This X-ray Bragg optics is composed of two magnifiers in a crossed arrangement, and the magnification factor, M, is controlled through the azimuth angle of each magnifier. The basic properties of the X-ray optics such as the magnification factor, image transformation matrix and intrinsic acceptance angle are described based on the dynamical theory of X-ray diffraction. The feasibility of the variable-magnification X-ray Bragg optics was verified at the vertical-wiggler beamline BL-14B of the Photon Factory. For X-ray Bragg magnifiers, Si(22...
Source: Journal of Synchrotron Radiation - June 25, 2015 Category: Physics Authors: Hirano, K.Yamashita, Y.Takahashi, Y.Sugiyama, H. Tags: X-ray magnifier variable-magnification dynamical diffraction imaging image processing research papers Source Type: research

Single-image phase retrieval using an edge illumination X-ray phase-contrast imaging setup
A method is proposed which enables the retrieval of the thickness or of the projected electron density of a sample from a single input image acquired with an edge illumination phase-contrast imaging setup. The method assumes the case of a quasi-homogeneous sample, i.e. a sample with a constant ratio between the real and imaginary parts of its complex refractive index. Compared with current methods based on combining two edge illumination images acquired in different configurations of the setup, this new approach presents advantages in terms of simplicity of acquisition procedure and shorter data collection time, which are ...
Source: Journal of Synchrotron Radiation - June 25, 2015 Category: Physics Authors: Diemoz, P.C.Vittoria, F.A.Hagen, C.K.Endrizzi, M.Coan, P.Brun, E.Wagner, U.H.Rau, C.Robinson, I.K.Bravin, A.Olivo, A. Tags: X-ray imaging phase-contrast imaging phase retrieval image formation theory research papers Source Type: research

Assessment of freeware programs for the reconstruction of tomography datasets obtained with a monochromatic synchrotron-based X-ray source
Synchrotron-based in-line phase-contrast computed tomography (PC-CT) allows soft tissue to be imaged with sub-gross resolution and has potential to be used as a diagnostic tool. The reconstruction and processing of in-line PC-CT datasets is a computationally demanding task; thus, an efficient and user-friendly software program is desirable. Four freeware programs (NRecon, PITRE, H-PITRE and Athabasca Recon) were compared for the availability of features such as dark- and flat-field calibration, beam power normalization, ring artifact removal, and alignment tools for optimizing image quality. An in-line PC-CT projection dat...
Source: Journal of Synchrotron Radiation - June 24, 2015 Category: Physics Authors: Wolkowski, B.Snead, E.Wesolowski, M.Singh, J.Pettitt, M.Chibbar, R.Melli, S.Montgomery, J. Tags: phase-contrast computed tomography computed tomography reconstruction teaching and education Source Type: research

Charge redistribution and a shortening of the Fe—As bond at the quantum critical point of SmO1–xFxFeAs
Many researchers have pointed out that there is a quantum critical point (QCP) in the F-doped SmOFeAs system. In this paper, the electronic structure and local structure of the superconductive FeAs layer in SmO1–xFxFeAs as a function of the F-doping concentration have been investigated using Fe and As K-edge X-ray absorption spectroscopy. Experiments performed on the X-ray absorption near-edge structure showed that in the vicinity of the QCP the intensity of the pre-edge feature at the Fe-edge decreases continuously, while there is a striking rise of the shoulder-peak at the As edge, suggesting the occurrence of char...
Source: Journal of Synchrotron Radiation - June 24, 2015 Category: Physics Authors: Cheng, J.Dong, P.Xu, W.Liu, S.Chu, W.Chen, X.Wu, Z. Tags: quantum critical point iron-based superconductor XAS electronic structure local structure research papers Source Type: research

Picosecond-resolved X-ray absorption spectroscopy at low signal contrast using a hard X-ray streak camera
A picosecond-resolving hard-X-ray streak camera has been in operation for several years at Sector 7 of the Advanced Photon Source (APS). Several upgrades have been implemented over the past few years to optimize integration into the beamline, reduce the timing jitter, and improve the signal-to-noise ratio. These include the development of X-ray optics for focusing the X-rays into the sample and the entrance slit of the streak camera, and measures to minimize the amount of laser light needed to generate the deflection-voltage ramp. For the latter, the photoconductive switch generating the deflection ramp was replaced with m...
Source: Journal of Synchrotron Radiation - June 24, 2015 Category: Physics Authors: Adams, B.W.Rose-Petruck, C.Jiao, Y. Tags: X-ray streak camera high repetition rate ultrafast laser photochemistry research papers Source Type: research

Compound focusing mirror and X-ray waveguide optics for coherent imaging and nano-diffraction
A compound optical system for coherent focusing and imaging at the nanoscale is reported, realised by high-gain fixed-curvature elliptical mirrors in combination with X-ray waveguide optics or different cleaning apertures. The key optical concepts are illustrated, as implemented at the Göttingen Instrument for Nano-Imaging with X-rays (GINIX), installed at the P10 coherence beamline of the PETRA III storage ring at DESY, Hamburg, and examples for typical applications in biological imaging are given. Characteristic beam configurations with the recently achieved values are also described, meeting the different requireme...
Source: Journal of Synchrotron Radiation - June 23, 2015 Category: Physics Authors: Salditt, T.Osterhoff, M.Krenkel, M.Wilke, R.N.Priebe, M.Bartels, M.Kalbfleisch, S.Sprung, M. Tags: coherent imaging nano-diffraction waveguides holography feature articles Source Type: research

Focusing performance of a multilayer Laue lens with layer placement error described by dynamical diffraction theory
The multilayer Laue lens (MLL) is essentially a linear zone plate with large aspect ratio, which can theoretically focus hard X-rays to well below 1 nm with high efficiency when ideal structures are used. However, the focusing performance of a MLL depends heavily on the quality of the layers, especially the layer placement error which always exists in real MLLs. Here, a dynamical modeling approach, based on the coupled wave theory, is proposed to study the focusing performance of a MLL with layer placement error. The result of simulation shows that this method can be applied to various forms of layer placement error. (So...
Source: Journal of Synchrotron Radiation - June 19, 2015 Category: Physics Authors: Hu, L.Chang, G.Liu, P.Zhou, L. Tags: multilayer Laue lens dynamical diffraction theory layer placement error research papers Source Type: research

The Extreme Conditions Beamline P02.2 and the Extreme Conditions Science Infrastructure at PETRA III
A detailed description is presented of the Extreme Conditions Beamline P02.2 for micro X-ray diffraction studies of matter at simultaneous high pressure and high/low temperatures at PETRA III, in Hamburg, Germany. This includes performance of the X-ray optics and instrumental resolution as well as an overview of the different sample environments available for high-pressure studies in the diamond anvil cell. Particularly emphasized are the high-brilliance and high-energy X-ray diffraction capabilities of the beamline in conjunction with the use of fast area detectors to conduct time-resolved compression studies in the mil...
Source: Journal of Synchrotron Radiation - June 19, 2015 Category: Physics Authors: Liermann, H.-P.Konôpková, Z.Morgenroth, W.Glazyrin, K.Bednarčik, J.McBride, E.E.Petitgirard, S.Delitz, J.T.Wendt, M.Bican, Y.Ehnes, A.Schwark, I.Rothkirch, A.Tischer, M.Heuer, J.Schulte-Schrepping, H.Kracht, T.Franz, H. Tags: extreme conditions high-pressure high-temperature low temperature diamond anvil cell micro-diffraction time-resolved diffraction radial diffraction laser heating resistive heating cryostat PDF high energies research papers Source Type: research

High-accuracy X-ray absorption spectra from mM solutions of nickel (II) complexes with multiple solutions using transmission XAS
A new approach is introduced for determining X-ray absorption spectroscopy (XAS) spectra on absolute and relative scales using multiple solutions with different concentrations by the characterization and correction of experimental systematics. This hybrid technique is a development of standard X-ray absorption fine structure (XAFS) along the lines of the high-accuracy X-ray extended range technique (XERT) but with applicability to solutions, dilute systems and cold cell environments. This methodology has been applied to determining absolute XAS of bis(N-n-propyl-salicylaldiminato) nickel(II) and bis(N-i-propyl-salicylaldim...
Source: Journal of Synchrotron Radiation - June 19, 2015 Category: Physics Authors: Chantler, C.T.Islam, M.T.Best, S.P.Tantau, L.J.Tran, C.Q.Cheah, M.H.Payne, A.T. Tags: XAS with uncertainty hybrid technique transmission XAS nickel(II) complexes research papers Source Type: research

Phase-contrast computed tomography for quantification of structural changes in lungs of asthma mouse models of different severity
Lung imaging in mouse disease models is crucial for the assessment of the severity of airway disease but remains challenging due to the small size and the high porosity of the organ. Synchrotron inline free-propagation phase-contrast computed tomography (CT) with its intrinsic high soft-tissue contrast provides the necessary sensitivity and spatial resolution to analyse the mouse lung structure in great detail. Here, this technique has been applied in combination with single-distance phase retrieval to quantify alterations of the lung structure in experimental asthma mouse models of different severity. In order to mimic an...
Source: Journal of Synchrotron Radiation - June 17, 2015 Category: Physics Authors: Dullin, C.Larsson, E.Tromba, G.Markus, A.M.Alves, F. Tags: phase-contrast CT single-distance phase retrieval lung imaging asthma mouse models short communications Source Type: research

Characteristics of Friedel pairs and diffraction contrast tomography with non-perpendicular rotation axis
The characteristics of Friedel pairs in diffraction contrast tomography (DCT) are studied in the condition that the rotation axis of the sample is not exactly perpendicular to the incident X-ray direction. For the rotation axis approximately aligned along the vertical direction, the Friedel pairs close to the horizontal plane are insensitive to the non-perpendicularity of the rotation axis, and can be used to refine the sample-to-detector distance and X-ray energy, while the Friedel pairs close to the vertical direction are sensitive to the non-perpendicularity of the rotation axis, and can be used to determine the rotatio...
Source: Journal of Synchrotron Radiation - June 17, 2015 Category: Physics Authors: Yi, Q.Li, G.Zhang, J.Luo, S.-N.Fan, D.Gao, Z.Wang, Y.Gao, G.Jiang, S.Jiang, X. Tags: diffraction contrast tomography Friedel pair non-perpendicular rotation axis non-perpendicularity. research papers Source Type: research

A simple optical system delivering a tunable micrometer pink beam that can compensate for heat-induced deformations
The radiation from an undulator reflected from one or more optical elements (usually termed `pink-beam') is used in photon-hungry experiments. The optical elements serve as a high-energy cutoff and for focusing purposes. One of the issues with this configuration is maintaining the focal spot dimension as the energy of the undulator is varied, since this changes the heat load absorbed by the first optical element. Finite-element analyses of the power absorbed by a side water-cooled mirror exposed to the radiation emitted by an undulator at the Advanced Photon Source (APS) and at the APS after the proposed upgrade (APSU) rev...
Source: Journal of Synchrotron Radiation - June 9, 2015 Category: Physics Authors: Reininger, R.Liu, Z.Doumy, G.Young, L. Tags: ray tracings pink beam undulator radiation microfocusing heat load research papers Source Type: research

Quantitative phase retrieval in X-ray Zernike phase contrast microscopy
In recent years, increasing attention has been devoted to X-ray phase contrast imaging, since it can provide high-contrast images by using phase variations. Among the different existing techniques, Zernike phase contrast microscopy is one of the most popular phase-sensitive techniques for investigating the fine structure of the sample at high spatial resolution. In X-ray Zernike phase contrast microscopy, the image contrast is indeed a mixture of absorption and phase contrast. Therefore, this technique just provides qualitative information on the object, which makes the interpretation of the image difficult. In this contri...
Source: Journal of Synchrotron Radiation - June 9, 2015 Category: Physics Authors: Chen, H.Wang, Z.Gao, K.Hou, Q.Wang, D.Wu, Z. Tags: X-ray microscopy Zernike phase contrast phase retrieval phase ring research papers Source Type: research

Design and performance of the APPLE-Knot undulator
Along with the development of accelerator technology, synchrotron emittance has continuously decreased. This results in increased brightness, but also causes a heavy heat load on beamline optics. Recently, optical surfaces with 0.1 nm micro-roughness and 0.05 µrad slope error (r.m.s.) have become commercially available and surface distortions due to heat load have become a key factor in determining beamline performance, and heat load has become a serious problem at modern synchrotron radiation facilities. Here, APPLE-Knot undulators which can generate photons with arbitrary polarization, with low on-axis heat loa...
Source: Journal of Synchrotron Radiation - June 9, 2015 Category: Physics Authors: Ji, F.Chang, R.Zhou, Q.Zhang, W.Ye, M.Sasaki, S.Qiao, S. Tags: undulator Knot undulator figure-8 undulator APPLE undulator APPLE-8 undulator Apple-Knot undulator research papers Source Type: research

Two-dimensional in situ metrology of X-ray mirrors using the speckle scanning technique
In situ metrology overcomes many of the limitations of existing metrology techniques and is capable of exceeding the performance of present-day optics. A novel technique for precisely characterizing an X-ray bimorph mirror and deducing its two-dimensional (2D) slope error map is presented. This technique has also been used to perform fast optimization of a bimorph mirror using the derived 2D piezo response functions. The measured focused beam size was significantly reduced after the optimization, and the slope error map was then verified by using geometrical optics to simulate the focused beam profile. This proposed techni...
Source: Journal of Synchrotron Radiation - June 6, 2015 Category: Physics Authors: Wang, H.Kashyap, Y.Laundy, D.Sawhney, K. Tags: speckle X-ray optics metrology research papers Source Type: research

Live small-animal X-ray lung velocimetry and lung micro-tomography at the Australian Synchrotron Imaging and Medical Beamline
The high flux and coherence produced at long synchrotron beamlines makes them well suited to performing phase-contrast X-ray imaging of the airways and lungs of live small animals. Here, findings of the first live-animal imaging on the Imaging and Medical Beamline (IMBL) at the Australian Synchrotron are reported, demonstrating the feasibility of performing dynamic lung motion measurement and high-resolution micro-tomography. Live anaesthetized mice were imaged using 30 keV monochromatic X-rays at a range of sample-to-detector propagation distances. A frame rate of 100 frames s−1 allowed lung motion to be deter...
Source: Journal of Synchrotron Radiation - June 6, 2015 Category: Physics Authors: Murrie, R.P.Morgan, K.S.Maksimenko, A.Fouras, A.Paganin, D.M.Hall, C.Siu, K.K.W.Parsons, D.W.Donnelley, M. Tags: lung X-ray velocimetry microtomography phase contrast research papers Source Type: research

Distinct effect of xenobiotics on the metal-binding properties of protein molecules
The X-ray standing-wave method was applied to study the elemental composition and molecular organization of ordered protein films of alkaline phosphatase exposed to different xenobiotics (drug compounds, lead). Binding of metal ions from triply distilled water to protein molecules has been experimentally observed. Definite differences in the arrangement of impurity metal ions in the films have been established. The considerable enhancement of protein–metal interactions is attributed to partial rearrangement of the protein native structure, induced by xenobiotics. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - June 6, 2015 Category: Physics Authors: Novikova, N.Kovalchuk, M.Stepina, N.Gaynutdinov, R.Chukhrai, E.Yurieva, E. Tags: alkaline phosphatase trace metal binding chelating drug compounds Langmuir – Blodgett monolayer X-ray fluorescence X-ray total external reflection research papers Source Type: research

Laue-DIC: a new method for improved stress field measurements at the micrometer scale
A better understanding of the effective mechanical behavior of polycrystalline materials requires an accurate knowledge of the behavior at a scale smaller than the grain size. The X-ray Laue microdiffraction technique available at beamline BM32 at the European Synchrotron Radiation Facility is ideally suited for probing elastic strains (and associated stresses) in deformed polycrystalline materials with a spatial resolution smaller than a micrometer. However, the standard technique used to evaluate local stresses from the distortion of Laue patterns lacks accuracy for many micromechanical applications, mostly due to (i) th...
Source: Journal of Synchrotron Radiation - May 9, 2015 Category: Physics Authors: Petit, J.Castelnau, O.Bornert, M.Zhang, F.G.Hofmann, F.Korsunsky, A.M.Faurie, D.Le Bourlot, C.Micha, J.S.Robach, O.Ulrich, O. Tags: X-ray diffraction microbeam stress field elastic strain research papers Source Type: research

PRIGo: a new multi-axis goniometer for macromolecular crystallography
The Parallel Robotics Inspired Goniometer (PRIGo) is a novel compact and high-precision goniometer providing an alternative to (mini-)kappa, traditional three-circle goniometers and Eulerian cradles used for sample reorientation in macromolecular crystallography. Based on a combination of serial and parallel kinematics, PRIGo emulates an arc. It is mounted on an air-bearing stage for rotation around ω and consists of four linear positioners working synchronously to achieve x, y, z translations and χ rotation (0–90°), followed by a ϕ stage (0–360°) for rotation around the sample holder axi...
Source: Journal of Synchrotron Radiation - May 9, 2015 Category: Physics Authors: Waltersperger, S.Olieric, V.Pradervand, C.Glettig, W.Salathe, M.Fuchs, M.R.Curtin, A.Wang, X.Ebner, S.Panepucci, E.Weinert, T.Schulze-Briese, C.Wang, M. Tags: multi-axis goniometry macromolecular crystallography diffractometer diffraction data collection strategy beamline endstation research papers Source Type: research

X-ray pulse wavefront metrology using speckle tracking
An instrument allowing the quantitative analysis of X-ray pulsed wavefronts is presented and its processing method explained. The system relies on the X-ray speckle tracking principle to accurately measure the phase gradient of the X-ray beam from which beam optical aberrations can be deduced. The key component of this instrument, a semi-transparent scintillator emitting visible light while transmitting X-rays, allows simultaneous recording of two speckle images at two different propagation distances from the X-ray source. The speckle tracking procedure for a reference-less metrology mode is described with a detailed accou...
Source: Journal of Synchrotron Radiation - May 9, 2015 Category: Physics Authors: Berujon, S.Ziegler, E.Cloetens, P. Tags: metrology phase sensing wavefront speckle research papers Source Type: research

Vibration measurements of high-heat-load monochromators for DESY PETRA III extension
The requirement for vibrational stability of beamline optics continues to evolve rapidly to comply with the demands created by the improved brilliance of the third-generation low-emittance storage rings around the world. The challenge is to quantify the performance of the instrument before it is installed at the beamline. In this article, measurement techniques are presented that directly and accurately measure (i) the relative vibration between the two crystals of a double-crystal monochromator (DCM) and (ii) the absolute vibration of the second-crystal cage of a DCM. Excluding a synchrotron beam, the measurements are con...
Source: Journal of Synchrotron Radiation - May 8, 2015 Category: Physics Authors: Kristiansen, P.Horbach, J.Döhrmann, R.Heuer, J. Tags: cryocooled DCM vibration research papers Source Type: research

Current events
(Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 30, 2015 Category: Physics Authors: , Tags: current events Source Type: research

In situ synchrotron X-ray diffraction investigation of the evolution of a PbO2/PbSO4 surface layer on a copper electrowinning Pb anode in a novel electrochemical flow cell. Corrigendum
Figures 7 and 8 of the article by Clancy et al. [(2015), J. Synchrotron Rad. 22, 366–375] are corrected. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 30, 2015 Category: Physics Authors: Clancy, M.Styles, M.J.Bettles, C.J.Birbilis, N.Chen, M.Zhang, Y.Gu, Q.Kimpton, J.A.Webster, N.A.S. Tags: PbO2 PbSO4 electrochemical cycling flow cell in situ X-ray diffraction Rietveld refinement quantitative phase analysis addenda and errata Source Type: research

CDApps: integrated software for experimental planning and data processing at beamline B23, Diamond Light Source. Corrigendum
In the paper by Hussain et al. [(2015), J. Synchrotron Rad. 22, 465–468], Daniel Myatt is missing from the list of authors. The complete list of authors should be Rohanah Hussain, Kristian Benning, Daniel Myatt, Tamas Javorfi, Edoardo Longo, Timothy R. Rudd, Bill Pulford and Giuliano Siligardi. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 30, 2015 Category: Physics Authors: Hussain, R.Benning, K.Myatt, D.Javorfi, T.Longo, E.Rudd, T.R.Pulford, B.Siligardi, G. Tags: synchrotron radiation circular dichroism (SRCD) vacuum-ultraviolet (VUV) secondary structure protein denaturation CDApps integrated software addenda and errata Source Type: research

An introduction to the special issue on X-ray free-electron lasers
This issue of the Journal of Synchrotron Radiation is a special issue on X-ray free-electron lasers. Here, a brief introduction to these special issue papers is given. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 30, 2015 Category: Physics Authors: Schlichting, I.White, W.E.Yabashi, M. Tags: X-ray free-electron lasers XFELs editorial Source Type: research

Water window ptychographic imaging with characterized coherent X-rays
A ptychographical coherent diffractive imaging experiment in the water window with focused soft X-rays at 500 eV is reported. An X-ray beam with high degree of coherence was selected for ptychography at the P04 beamline of PETRA III synchrotron radiation source. The beam coherence was measured with the newly developed non-redundant array method, and a coherence length of 4.1 µm and global degree of coherence of 35% at 100 µm exit slit opening in the vertical direction were determined. A pinhole, 2.6 µm in size, selected the coherent part of the beam that was used to obtain ptychographic reconstruc...
Source: Journal of Synchrotron Radiation - April 23, 2015 Category: Physics Authors: Rose, M.Skopintsev, P.Dzhigaev, D.Gorobtsov, O.Senkbeil, T.Gundlach, A. vonGorniak, T.Shabalin, A.Viefhaus, J.Rosenhahn, A.Vartanyants, I. Tags: ptychography non-redundant array water window imaging diatom research papers Source Type: research

Dual-energy X-ray analysis using synchrotron computed tomography at 35 and 60 keV for the estimation of photon interaction coefficients describing attenuation and energy absorption
A novel method for dual-energy X-ray analysis (DEXA) is tested using measurements of the X-ray linear attenuation coefficient μ. The key is a mathematical model that describes elemental cross sections using a polynomial in atomic number. The model is combined with the mixture rule to describe μ for materials, using the same polynomial coefficients. Materials are characterized by their electron density Ne and statistical moments Rk describing their distribution of elements, analogous to the concept of effective atomic number. In an experiment with materials of known density and composition, measurements of μ are wr...
Source: Journal of Synchrotron Radiation - April 23, 2015 Category: Physics Authors: Midgley, S.Schleich, N. Tags: linear attenuation coefficient mass energy absorption coefficient dual-energy X-ray analysis research papers Source Type: research

Simultaneous multiplexed materials characterization using a high-precision hard X-ray micro-slit array
The needs both for increased experimental throughput and for in operando characterization of functional materials under increasingly realistic experimental conditions have emerged as major challenges across the whole of crystallography. A novel measurement scheme that allows multiplexed simultaneous measurements from multiple nearby sample volumes is presented. This new approach enables better measurement statistics or direct probing of heterogeneous structure, dynamics or elemental composition. To illustrate, the submicrometer precision that optical lithography provides has been exploited to create a multiplexed form of u...
Source: Journal of Synchrotron Radiation - April 22, 2015 Category: Physics Authors: Zhang, F.Allen, A.J.Levine, L.E.Mancini, D.C.Ilavsky, J. Tags: measurement-in-parallel simultaneous in operando characterization heterogeneous structure uncertainty reduction multiplexed materials characterization research papers Source Type: research

Optical laser systems at the Linac Coherent Light Source
Ultrafast optical lasers play an essential role in exploiting the unique capabilities of recently commissioned X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS). Pump–probe experimental techniques reveal ultrafast dynamics in atomic and molecular processes and reveal new insights in chemistry, biology, material science and high-energy-density physics. This manuscript describes the laser systems and experimental methods that enable cutting-edge optical laser/X-ray pump–probe experiments to be performed at LCLS. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 22, 2015 Category: Physics Authors: Minitti, M.P.Robinson, J.S.Coffee, R.N.Edstrom, S.Gilevich, S.Glownia, J.M.Granados, E.Hering, P.Hoffmann, M.C.Miahnahri, A.Milathianaki, D.Polzin, W.Ratner, D.Tavella, F.Vetter, S.Welch, M.White, W.E.Fry, A.R. Tags: FEL ultrafast lasers pump – probe research papers Source Type: research

Effects of self-seeding and crystal post-selection on the quality of Monte Carlo-integrated SFX data
Serial femtosecond crystallography (SFX) is an emerging method for data collection at free-electron lasers (FELs) in which single diffraction snapshots are taken from a large number of crystals. The partial intensities collected in this way are then combined in a scheme called Monte Carlo integration, which provides the full diffraction intensities. However, apart from having to perform this merging, the Monte Carlo integration must also average out all variations in crystal quality, crystal size, X-ray beam properties and other factors, necessitating data collection from thousands of crystals. Because the pulses provided ...
Source: Journal of Synchrotron Radiation - April 22, 2015 Category: Physics Authors: Barends, T.White, T.A.Barty, A.Foucar, L.Messerschmidt, M.Alonso-Mori, R.Botha, S.Chapman, H.Doak, R.B.Galli, L.Gati, C.Gutmann, M.Koglin, J.Markvardsen, A.Nass, K.Oberthur, D.Shoeman, R.L.Schlichting, I.Boutet, S. Tags: free-electron laser serial femtosecond crystallography data processing protein crystallography research papers Source Type: research

Correction of complex nonlinear signal response from a pixel array detector
The pulsed free-electron laser light sources represent a new challenge to photon area detectors due to the intrinsic spontaneous X-ray photon generation process that makes single-pulse detection necessary. Intensity fluctuations up to 100% between individual pulses lead to high linearity requirements in order to distinguish small signal changes. In real detectors, signal distortions as a function of the intensity distribution on the entire detector can occur. Here a robust method to correct this nonlinear response in an area detector is presented for the case of exposures to similar signals. The method is tested for the ca...
Source: Journal of Synchrotron Radiation - April 22, 2015 Category: Physics Authors: van Driel, T.B.Herrmann, S.Carini, G.Nielsen, M.M.Lemke, H.T. Tags: FEL detector nonlinearity diffuse scattering research papers Source Type: research

High-resolution X-ray emission spectroscopy with transition-edge sensors: present performance and future potential
X-ray emission spectroscopy (XES) is a powerful element-selective tool to analyze the oxidation states of atoms in complex compounds, determine their electronic configuration, and identify unknown compounds in challenging environments. Until now the low efficiency of wavelength-dispersive X-ray spectrometer technology has limited the use of XES, especially in combination with weaker laboratory X-ray sources. More efficient energy-dispersive detectors have either insufficient energy resolution because of the statistical limits described by Fano or too low counting rates to be of practical use. This paper updates an approach...
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: Uhlig, J.Doriese, W.B.Fowler, J.W.Swetz, D.S.Jaye, C.Fischer, D.A.Reintsema, C.D.Bennett, D.A.Vale, L.R.Mandal, U.O'Neil, G.C.Miaja-Avila, L.Joe, Y.I.El Nahhas, A.Fullagar, W.Parnefjord Gustafsson, F.Sundström, V.Kurunthu, D.Hilton, G.C.Schmidt, D.R.Ullo Tags: X-ray spectroscopy energy-dispersive X-ray detector X-ray emission spectroscopy (XES) resonant inelastic x-ray scattering (RIXS) low-temperature detector microcalorimeter research papers Source Type: research

X-ray detectors at the Linac Coherent Light Source
Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation...
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: Blaj, G.Caragiulo, P.Carini, G.Carron, S.Dragone, A.Freytag, D.Haller, G.Hart, P.Hasi, J.Herbst, R.Herrmann, S.Kenney, C.Markovic, B.Nishimura, K.Osier, S.Pines, J.Reese, B.Segal, J.Tomada, A.Weaver, M. Tags: FEL X-ray detectors fast readout research papers Source Type: research

The FERMI free-electron lasers
FERMI is a seeded free-electron laser (FEL) facility located at the Elettra laboratory in Trieste, Italy, and is now in user operation with its first FEL line, FEL-1, covering the wavelength range between 100 and 20 nm. The second FEL line, FEL-2, a high-gain harmonic generation double-stage cascade covering the wavelength range 20–4 nm, has also completed commissioning and the first user call has been recently opened. An overview of the typical operating modes of the facility is presented. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: Allaria, E.Badano, L.Bassanese, S.Capotondi, F.Castronovo, D.Cinquegrana, P.Danailov, M.B.D'Auria, G.Demidovich, A.De Monte, R.De Ninno, G.Di Mitri, S.Diviacco, B.Fawley, W.M.Ferianis, M.Ferrari, E.Gaio, G.Gauthier, D.Giannessi, L.Iazzourene, F.Kurdi, G.M Tags: lasers free-electron lasers coherence research papers Source Type: research

The Low Density Matter (LDM) beamline at FERMI: optical layout and first commissioning
The Low Density Matter (LDM) beamline has been built as part of the FERMI free-electron laser (FEL) facility to serve the atomic, molecular and cluster physics community. After the commissioning phase, it received the first external users at the end of 2012. The design and characterization of the LDM photon transport system is described, detailing the optical components of the beamline. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: Svetina, C.Grazioli, C.Mahne, N.Raimondi, L.Fava, C.Zangrando, M.Gerusina, S.Alagia, M.Avaldi, L.Cautero, G.de Simone, M.Devetta, M.Di Fraia, M.Drabbels, M.Feyer, V.Finetti, P.Katzy, R.Kivimäki, A.Lyamayev, V.Mazza, T.Moise, A.Möller, T.O'Keeffe, P.Ovch Tags: beamline free-electron laser low-density matter photon transport metrology research papers Source Type: research

The Linac Coherent Light Source
(LCLS) at the SLAC National Accelerator Laboratory was the first hard X-ray free-electron laser (FEL) to operate as a user facility. After five years of operation, LCLS is now a mature FEL user facility. Our personal views about opportunities and challenges inherent to these unique light sources are discussed. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: White, W.E.Robert, A.Dunne, M. Tags: FEL, X-ray Linac Coherent Light Source research papers Source Type: research

The X-ray Pump–Probe instrument at the Linac Coherent Light Source
The X-ray Pump–Probe instrument achieves femtosecond time-resolution with hard X-ray methods using a free-electron laser source. It covers a photon energy range of 4–24 keV. A femtosecond optical laser system is available across a broad spectrum of wavelengths for generating transient states of matter. The instrument is designed to emphasize versatility and the scientific goals encompass ultrafast physical, chemical and biological processes involved in the transformation of matter and transfer of energy at the atomic scale. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: Chollet, M.Alonso-Mori, R.Cammarata, M.Damiani, D.Defever, J.Delor, J.T.Feng, Y.Glownia, J.M.Langton, J.B.Nelson, S.Ramsey, K.Robert, A.Sikorski, M.Song, S.Stefanescu, D.Srinivasan, V.Zhu, D.Lemke, H.T.Fritz, D.M. Tags: FEL X-ray pump – probe time-resolved research papers Source Type: research

The Matter in Extreme Conditions instrument at the Linac Coherent Light Source
The LCLS beam provides revolutionary capabilities for studying the transient behavior of matter in extreme conditions. The particular strength of the Matter in Extreme Conditions instrument is that it combines the unique LCLS beam with high-power optical laser beams, and a suite of dedicated diagnostics tailored for this field of science. In this paper an overview of the beamline, the capabilities of the instrumentation, and selected highlights of experiments and commissioning results are presented. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 21, 2015 Category: Physics Authors: Nagler, B.Arnold, B.Bouchard, G.Boyce, R.F.Boyce, R.M.Callen, A.Campell, M.Curiel, R.Galtier, E.Garofoli, J.Granados, E.Hastings, J.Hays, G.Heimann, P.Lee, R.W.Milathianaki, D.Plummer, L.Schropp, A.Wallace, A.Welch, M.White, W.Xing, Z.Yin, J.Young, J.Zast Tags: FEL high energy density science warm dense matter X-ray Thomson scattering high-pressure science research papers Source Type: research

Simultaneous nanocalorimetry and fast XRD measurements to study the silicide formation in Pd/a-Si bilayers
The use of a membrane-based chip nanocalorimeter in a powder diffraction beamline is described. Simultaneous wide-angle X-ray scattering and scanning nanocalorimetric measurements are performed on a thin-film stack of palladium/amorphous silicon (Pd/a-Si) at heating rates from 0.1 to 10 K s−1. The nanocalorimeter works under a power-compensation scheme previously developed by the authors. Kinetic and structural information of the consumed and created phases can be obtained from the combined techniques. The formation of Pd2Si produces a broad calorimetric peak that contains overlapping individual processes. It is ...
Source: Journal of Synchrotron Radiation - April 17, 2015 Category: Physics Authors: Molina-Ruiz, M.Ferrando-Villalba, P.Rodríguez-Tinoco, C.Garcia, G.Rodríguez-Viejo, J.Peral, I.Lopeandía, A.F. Tags: nanocalorimetry thin-film stack WAXS research papers Source Type: research

The Atomic, Molecular and Optical Science instrument at the Linac Coherent Light Source
The Atomic, Molecular and Optical Science (AMO) instrument at the Linac Coherent Light Source (LCLS) provides a tight soft X-ray focus into one of three experimental endstations. The flexible instrument design is optimized for studying a wide variety of phenomena requiring peak intensity. There is a suite of spectrometers and two photon area detectors available. An optional mirror-based split-and-delay unit can be used for X-ray pump–probe experiments. Recent scientific highlights illustrate the imaging, time-resolved spectroscopy and high-power density capabilities of the AMO instrument. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 17, 2015 Category: Physics Authors: Ferguson, K.R.Bucher, M.Bozek, J.D.Carron, S.Castagna, J.-C.Coffee, R.Curiel, G.I.Holmes, M.Krzywinski, J.Messerschmidt, M.Minitti, M.Mitra, A.Moeller, S.Noonan, P.Osipov, T.Schorb, S.Swiggers, M.Wallace, A.Yin, J.Bostedt, C. Tags: FEL X-ray ultrafast spectroscopy imaging research papers Source Type: research

Multipurpose end-station for coherent diffraction imaging and scattering at FERMI@Elettra free-electron laser facility
The Diffraction and Projection Imaging (DiProI) beamline at FERMI, the Elettra free-electron laser (FEL), hosts a multi-purpose station that has been opened to users since the end of 2012. This paper describes the core capabilities of the station, designed to make use of the unique features of the FERMI-FEL for performing a wide range of static and dynamic scattering experiments. The various schemes for time-resolved experiments, employing both soft X-ray FEL and seed laser IR radiation are presented by using selected recent results. The ongoing upgrade is adding a reflection geometry setup for scattering experiments, expa...
Source: Journal of Synchrotron Radiation - April 17, 2015 Category: Physics Authors: Capotondi, F.Pedersoli, E.Bencivenga, F.Manfredda, M.Mahne, N.Raimondi, L.Svetina, C.Zangrando, M.Demidovich, A.Nikolov, I.Danailov, M.Masciovecchio, C.Kiskinova, M. Tags: coherent diffraction imaging holography scattering free-electron laser time-resolved experiments research papers Source Type: research

Data acquisition system for X-ray free-electron laser experiments at SACLA
A data acquisition system for X-ray free-electron laser experiments at SACLA has been developed. The system has been designed for reliable shot-to-shot data storage with a high data stream greater than 4 Gbps and massive data analysis. Configuration of the system and examples of prompt data analysis during experiments are presented. Upgrade plans for the system to extend flexibility are described. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 17, 2015 Category: Physics Authors: Joti, Y.Kameshima, T.Yamaga, M.Sugimoto, T.Okada, K.Abe, T.Furukawa, Y.Ohata, T.Tanaka, R.Hatsui, T.Yabashi, M. Tags: X-ray free-electron laser shot-to-shot data acquisition massive data analysis research papers Source Type: research

Recent results of PADReS, the Photon Analysis Delivery and REduction System, from the FERMI FEL commissioning and user operations
The Photon Analysis Delivery and REduction System of FERMI (PADReS) has been routinely used during the machine commissioning and operations of FERMI since 2011. It has also served the needs of several user runs at the facility from late 2012. The system is endowed with online and shot-to-shot diagnostics giving information about intensity, spatial-angular distribution, spectral content, as well as other diagnostics to determine coherence, pulse length etc. Moreover, PADReS is capable of manipulating the beam in terms of intensity and optical parameters. Regarding the optics, besides a standard refocusing system based on an...
Source: Journal of Synchrotron Radiation - April 16, 2015 Category: Physics Authors: Zangrando, M.Cocco, D.Fava, C.Gerusina, S.Gobessi, R.Mahne, N.Mazzucco, E.Raimondi, L.Rumiz, L.Svetina, C. Tags: photon transport photon diagnostics FEL research papers Source Type: research

Diverse application platform for hard X-ray diffraction in SACLA (DAPHNIS): application to serial protein crystallography using an X-ray free-electron laser
An experimental system for serial femtosecond crystallography using an X-ray free-electron laser (XFEL) has been developed. It basically consists of a sample chamber, fluid injectors and a two-dimensional detector. The chamber and the injectors are operated under helium atmosphere at 1 atm. The ambient pressure operation facilitates applications to fluid samples. Three kinds of injectors are employed to feed randomly oriented crystals in aqueous solution or highly viscous fluid. Experiments on lysozyme crystals were performed by using the 10 keV XFEL of the SPring-8 Angstrom Compact free-electron LAser (SACLA). The str...
Source: Journal of Synchrotron Radiation - April 16, 2015 Category: Physics Authors: Tono, K.Nango, E.Sugahara, M.Song, C.Park, J.Tanaka, T.Tanaka, R.Joti, Y.Kameshima, T.Ono, S.Hatsui, T.Mizohata, E.Suzuki, M.Shimamura, T.Tanaka, Y.Iwata, S.Yabashi, M. Tags: serial femtosecond crystallography XFEL research papers Source Type: research

Overview of the SACLA facility
In March 2012, SACLA started user operations of the first compact X-ray free-electron laser (XFEL) facility. SACLA has been routinely providing users with stable XFEL light over a wide photon energy range from 4 to 15 keV and an ultrafast pulse duration below 10 fs. The facility supports experimental activities in broad fields by offering high-quality X-ray optics and diagnostics, as well as reliable multiport charge-coupled-device detectors, with flexible experimental configurations. A two-stage X-ray focusing system was developed that enables the highest intensity of 1020 W cm−2. Key scientific results publ...
Source: Journal of Synchrotron Radiation - April 16, 2015 Category: Physics Authors: Yabashi, M.Tanaka, H.Ishikawa, T. Tags: X-ray free-electron laser beamline instrumentation X-ray optics ultrafast X-ray science quantum X-ray optics research papers Source Type: research

Phase-preserving beam expander for biomedical X-ray imaging
The BioMedical Imaging and Therapy beamlines at the Canadian Light Source are used by many researchers to capture phase-based imaging data. These experiments have so far been limited by the small vertical beam size, requiring vertical scanning of biological samples in order to image their full vertical extent. Previous work has been carried out to develop a bent Laue beam-expanding monochromator for use at these beamlines. However, the first attempts exhibited significant distortion in the diffraction plane, increasing the beam divergence and eliminating the usefulness of the monochromator for phase-related imaging techniq...
Source: Journal of Synchrotron Radiation - April 15, 2015 Category: Physics Authors: Martinson, M.Samadi, N.Bassey, B.Gomez, A.Chapman, D. Tags: beam expander bent Laue diffraction double-crystal monochromator biomedical imaging dynamic imaging in-line phase imaging polychromatic focus research papers Source Type: research

The Coherent X-ray Imaging instrument at the Linac Coherent Light Source
The Coherent X-ray Imaging (CXI) instrument specializes in hard X-ray, in-vacuum, high power density experiments in all areas of science. Two main sample chambers, one containing a 100 nm focus and one a 1 µm focus, are available, each with multiple diagnostics, sample injection, pump–probe and detector capabilities. The flexibility of CXI has enabled it to host a diverse range of experiments, from biological to extreme matter. (Source: Journal of Synchrotron Radiation)
Source: Journal of Synchrotron Radiation - April 15, 2015 Category: Physics Authors: Liang, M.Williams, G.J.Messerschmidt, M.Seibert, M.M.Montanez, P.A.Hayes, M.Milathianaki, D.Aquila, A.Hunter, M.S.Koglin, J.E.Schafer, D.W.Guillet, S.Busse, A.Bergan, R.Olson, W.Fox, K.Stewart, N.Curtis, R.Miahnahri, A.A.Boutet, S. Tags: FEL coherent diffracted imaging serial femtosecond crystallography protein crystallography single molecule imaging research papers Source Type: research