Phase-Contrast Mammography at the SYRMEP Beamline of Elettra

At the SYnchrotron Radiation for MEdical Physics (SYRMEP) beamline of Elettra, a widespread research activity in bio-medical imaging has been developed since 1997 [1 Arfelli, F. 1998. Low-dose phase contrast X-ray medical imaging. Phys. Med. Biol, 43: 2845 [Google Scholar]]. The core program carried out by the SYRMEP research team concerns the use of synchrotron radiation (SR) for mammography in the effort of improving image diagnostic quality innovating the imaging technique and the detection system.     

Characterization of polymer thin films with small‐angle X‐ray scattering under grazing incidence (GISAXS)

FEMTO, a femtosecond (fs) X-ray source based on laser interaction with a relativistic electron beam, began operation in the fall of 2006. It is installed at the μXAS beamline of the Swiss Light Source (SLS) at the Paul Scherrer Institut, Villigen. “Laser slicing” of an electron beam has first been proposed and demonstrated at the ALS [] and has recently been implemented at BESSY [2 Khan, S. 2006. Phys. Rev. Lett, 97: 074801[Crossref], [Web of Science ®] , [Google Scholar]] to generate fs soft X-rays (1–2 keV) with variable polarization. FEMTO is the first undulator source providing tunable, fs hard X-rays in the range 4.5–12 keV for laser/X-ray pump-probe absorption and diffraction experiments.     

Photon-In/Photon-Out Soft X-ray Spectroscopy at the TPS 45A Beamline

Owing to the current energy crisis and extreme changes in the global climate, there is great interest in finding renewable energy resources. Vast progress has been made in the development of new materials related to renewable energy, and their physical/chemical properties can be tailored by nanostructuring and other advanced synthetic approaches. In many important energy systems, such as solar hydrogen systems, the atomic/electronic structures of materials and fundamental interfacial phenomena of systems critically determine the energy conversion efficiency of materials [1 S. Shen et al., Energy Environ. Sci. 9, 2744 (2016).[Crossref], [Web of Science ®] , [Google Scholar], 2 J. Chen et al., J. Mater. Chem. A 2, 4605 (2014).[Crossref], [Web of Science ®] , [Google Scholar]]. Without knowledge of the fundamental electronic structures of the materials during conversion reactions, better engineering of the material for practical use is difficult. Understanding and controlling the interfaces in energy generation/conversion/storage materials requires in-situ/operando approaches [3 V. Iablokov et al., Nano Lett. 12, 2091 (2012).[Crossref], [Web of Science ®] , [Google Scholar], 4 F. Zheng et al., Nano Lett. 11, 847 (2011).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]]. The Taiwan Photon Source (TPS) Soft X-ray Spectroscopic beamline provides the capabilities for X-ray absorption (XAS) and X-ray emission (XES) spectroscopies, which can be utilized to investigate unoccupied (conduction-band) and occupied (valence-band) electronic states, respectively. Moreover, resonant inelastic X-ray scattering (RIXS) can be used to study intra-band (including d-d or f-f excitations) and inter-band (charge transfer) transitions [5 S. M. Butorin et al., Phys. Rev. Lett. 77, 574 (1996).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 6 P. Kuiper et al., Phys. Rev. Lett. 80, 5204 (1988).[Crossref], [Web of Science ®] , [Google Scholar]]. The former provides details about electronic energy splitting in various crystal fields and the latter involves electron transfer between a metal and a ligand, which determines chemical activity [7 H. Liu, Nano Lett. 7, 1919 (2007).[Crossref], [Web of Science ®] , [Google Scholar], 8 V. Bisogni et al., Phys. Rev. Lett. 114, 096402 (2015).[Crossref], [Web of Science ®] , [Google Scholar]].     

An X-ray Free Electron Laser Driven by an Ultimate Storage Ring

There is a worldwide interest in developing so-called ultimate storage ring (USR) light sources having electron emittances near the X-ray diffraction limit that would provide spectral brightness one or two orders of magnitude higher than present-day, third-generation sources and very large coherent flux in the multi-keV photon energy range [1 Hettel, R. and Qin, Q. 2013. Report on the Workshop on Accelerator R&D for Ultimate Storage Rings, Oct. 30–Nov. 1, 2012, Beijing, China, SLAC-PUB-15379, February [Google Scholar]]. At the same time, there is a growing scientific interest in X-ray FEL sources that can provide a continuous train of evenly spaced, low peak power, coherent photon pulses at repetition rates of above 1 kHz, unlike the bursts of much higher frequency pulses that can be provided by linac-based FELs pulsed with repetition rates of order 100 Hz or less. These CW sources would enable dynamic imaging of materials undergoing transitions in millisecond or less time scales and would open up the development of new non-line spectroscopic techniques that could lead to a better understanding of electronic and nuclear dynamics in materials.     

Sirius: A 5BA Low-Emittance Lattice with Superbends for the New Brazilian Synchrotron Light Source

Starting in the late 1980s and into the 1990s, Brazil developed its own technology for the production of synchrotron light, designing and building UVX, a light source based on a 1.37 GeV electron storage ring with a circumference of 93 m and natural emittance of 100 nm.rad [1 Liu, L., Jahnel, L. and Tavares, P. The LNLS UVX2 soft X-ray source. Proc. of the EPAC 92 Conference. Berlin. pp.450–452.  [Google Scholar]]. Over more than 15 years of routine operation for users, the expansion capabilities for this light source, either in terms of new beamlines or upgrades to its accelerators, have reached fundamental limits that can no longer be overcome. The first discussions about a new low-emittance light source for Brazil started in 2006 among the scientific and accelerator communities during the 16^th LNLS Annual Users Meeting. In November 2008, a decision by the Brazilian Federal Government was taken to fund preliminary studies for this new source, leading to the final decision to fund the whole project in 2011. The proposed new synchrotron light source, Sirius, is based on a 3 GeV electron storage ring with a circumference of 518 m, a natural emittance of 0.28 nm.rad, and a total of 20 straight sections, of which 18 are for insertion devices. The new facility is being built at the same LNLS site as shown in Figure 1.     

Technical Report: In-situ Monitoring and Validation of a Uranium Mill Tailings Management Facility Design Using X-ray Absorption Near Edge Structure (XANES) Spectroscopy

SOLEIL, a 2.75 GeV third-generation synchrotron light source [1 Nadji, A., Brunelle, P., Couprie, M.-E., Denard, J.-C., Filhol, J.-M., Lamarre, J.-F., Lebasque, P., Loulergue, A., Marchand, P., Nagaoka, R. and Nadolski, L. S. Proceedings of the Second International Particle Accelerator Conference. San Sebastian, Spain. pp.3002–3004.  [Google Scholar]], is presently delivering photons to 24 beamlines for users in five different filling patterns with top-up injection. The 430 mA multibunch (with three successive quarters filled; i.e., 312 out of 416 bunches) is complemented with time-resolved (hybrid multibunch, eight bunches and single bunch) and 4-2 ps bunch-length low-alpha modes. Even shorter bunches will be available at the end of 2013 with the forthcoming Femto-slicing project. With the continuous improvements of transverse beam position (200 nm RMS in the vertical plane) and the understanding of collective effects, the beam current and the stability provided to the beamlines have been steadily increased. New exotic modes of operation and upgrades of the optics to reduce the 3.9 nm.rad horizontal emittance are being studied.     

The Berkeley Center for Structural Biology at the Advanced Light Source

The Berkeley Center for Structural Biology (BCSB) operates and develops a suite of protein crystallography beamlines at the Advanced Light Source (ALS) located at Lawrence Berkeley National Laboratory (LBNL). Although the ALS was conceived as a low-energy (1.9-GeV), third-generation synchrotron source of vacuum ultraviolet (VUV) and soft X-ray radiation, it was realized during the development of the facility in the mid-1990s that a multipole wiggler coupled with brightness-preserving optics would result in a beamline whose performance in the energy range of 5 to 15 keV would be sufficient for most protein crystallographic experiments. Later, the hard X-ray capabilities of the ALS were expanded by the addition of three superconducting bending magnets, resulting in additional protein crystallography facilities at the ALS [1 A.A. MacDowell, J Synchrotron Radiation 11(6), 447–55 (2004).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]].     

X-ray transmission properties of intelligent anvils in diamond anvil cells

High-pressure and/or high-temperature analysis of geo- and material science samples routinely employs diamond anvil cells (DACs) as a research instrument. In particular, DACs allow for various in situ characterizations (e.g. Raman and Fourier transform infra red spectroscopies, X-ray diffraction (XRD), X-ray spectroscopy including fluorescence (XRF) and absorption (XAS)) at elevated pressure and temperature. The measurement of pressure (P) and/or temperature (T) in the sample chamber is crucial, but not always accurate, more specifically in the case of low-pressure applications (a few GPa). The development of modified diamonds (intelligent anvils ‘i-anvils’) adapted to a new generation of DACs (intelligent diamond anvil cells: iDAC) can contribute to solve this problem, as the diamond itself serves as the PT sensor, being prepared, for example, by high-energy ion implantation [H. Bureau, M. Burchard, S. Kubsky et al., This volume (2006).] on a micrometric scale. Several most interesting measurement methods used with DACs are based on X-ray techniques (e.g. XRF, XRD, XAS). We present the first results of X-ray transmission measurements with iDACs, performed at the hard-X-ray microfocus beamline ID22 at the ESRF (European Synchrotron Radiation Facility), Grenoble, France. Sensor response to intense irradiation as a function of X-ray energy (E _ph∈10;18.1 Burchard, M., Zaitsev, A. M. and Maresh, W. 2003. Rev. Sci. Instr., 74: 1263–1266.  [Google Scholar] keV) was investigated. The values of the sensor were found to be independent of the irradiation in the investigated energy range and thus validate the use of these sensors for precise and reliable measurements on a wide range of applications with high-energy synchrotron radiation. No influence of the sensor on the X-ray transmission properties of the anvil has been found.     

Meeting Report: Second International Workshop on Grazing Incidence Small Angle Scattering at HASYLAB

After the big success of the first GISAXS workshop in 2005, HASYLAB/DESY hosted the “2nd GISAXS Workshop 2007” in Hamburg, Germany, from May 9 to 11, 2007. GISAXS stands for Grazing Incidence Small Angle X-ray Scattering, a powerful surface sensitive technique to observe structures on multiple length scales, ranging from some nanometers to up to several micrometers. Organized by R. Gehrke and S.V. Roth from HASYLAB and P. Müller-Buschbaum from Technical University Munich, the workshop attracted more than 100 participants from more than 20 countries, making up a very exciting and stimulating atmosphere with invited keynote lectures, two sessions with more than 50 contributed posters, and practical training including real data acquisition at HASYLAB beamline BW4 [1 Roth, S. V., Döhrmann, R., Dommach, M., Kuhlmann, M., Kröger, I., Gehrke, R., Walter, H., Schroer, C., Lengeler, B. and Müller-Buschbaum, P. 2006. Rev. Sci. Instr, 77: 085106 [Google Scholar]].     

Large-Field X-ray Imaging at SPring-8 BL20B2

The medium-length (215 m) bending-magnet beamline 20B2 is allocated to medical applications and various X-ray micro imaging techniques (e.g., angiography, computed tomography, phase contrast imaging and diffraction topography) [1 S. Goto, Nuclear Instruments and Methods in Physics Research A 467–468, 682–685 (2001).[Crossref], [Web of Science ®] , [Google Scholar]]. The unique properties of BL20B2 are high spatial coherence (large coherent length) and its wide beam cross-section, which come from its long beam transport path and bending magnet light source. The horizontal angular aperture of BL20B2 is 1.5 mrad, as in all bending magnet beamlines at SPring-8. The horizontal beam width at the end station is larger than 300 mm for a 215 m beamline length.     

First observations of infrared synchrotron radiation at Elettra

Significant progress has been made in the last few years in short-bunch operation of third-generation synchrotron light sources, achieved by “lowα” optics for storage rings [1 Abo-Bakr, M. 2002. Phys. Rev. Lett., 88: 254801[Crossref], [PubMed] , [Google Scholar]–4 Müller, A.-S. Short-pulse operation of storage ring light sources. Proceedings of IPAC2013. Shanghai, China. (in press) [Google Scholar]]. The term α is a machine optics parameter describing the particle orbit length L as a function of the particle momentum p, L = L₀(1 + α(p ? p₀)/p₀), with respect to the nominal values indicated by the index “₀”. The “zero current” bunch length σ is then proportional to . Included here is the rf-voltage temporal gradient, V′ = dV/dt, which additionally influences the bunch length and will be required further. Thus, lowering α leads to a reduced bunch length all around the ring and radiation of the short bunches is supplied to all beamlines. These short bunches produce short X-ray pulses of equal length suitable for time-resolved measurements. Simultaneously, the short electron pulses emit intense, coherent THz radiation.     

First X-ray Absorption Spectroscopy at SSRP in 1974

The study of X-ray absorption spectroscopy (XAS) began at an exciting time in science. In the early years of the twentieth century, wave mechanics, X-ray diffraction, X-ray scattering from non-crystalline materials, electron diffraction, and XAS were all being developed simultaneously. Many XAS concepts and experimental techniques advanced in parallel with these other subjects; however, the difficulty of obtaining good XAS data from conventional X-ray tubes limited the field to a potentially interesting minor subject [1 R. Stumm von Bordwehr, Ann. Phys. Fr., 14, 377–466 (1989).[Crossref], [Web of Science ®] , [Google Scholar], 2 F. W. Lytle, J. Synchrotron Rad., 6, 123–134 (1999).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]].     

LURE in the 1970s

In France, Yvette Cauchois, Director of the Laboratoire de Chimie Physique in Paris, was the first person who came up with the idea of using synchrotron radiation. The experiment was done in collaboration with Italian scientists at the Frascati synchrotron in 1963 [1 Y. Cauchois, C. Bonnelle and G. Missoni, C. R. Acad. Sci. Paris, 257, 409 (1963a) and 1242 (1963b). [Google Scholar]]. For a few years, interesting results were obtained by her group and that of Pierre Jaéglé (Orsay) [2 P. Jaeglé, P. Missoni and P. Dhez, Phys. Rev. Lett., 18, 887 (1967).[Crossref], [Web of Science ®] , [Google Scholar]]. After that, they contacted the laboratory for high-energy physics at Orsay (LAL), hoping to install a beamline on the ACO (electron-positron collider), but their request was turned down.     

Magnetic Measurement Techniques for the Large-Scale Production of Undulator Segments for the European XFEL

The European X-ray free electron laser (EXFEL) facility is currently under construction [1 M. Altarelli, The European X-ray Free-electron Laser, Technical Design Report (2006). [Google Scholar]]. Using the principle of self-amplified spontaneous emission (SASE) [2 A.M. Kondratenko and E.L. Saldin, Part. Accel., 10, 207 (1980). [Google Scholar], 3 R. Bonifacio, C. Pellegrini, and L.M. Narducci, Opt. Commum. 50, 373 (1984).[Crossref], [Web of Science ®] , [Google Scholar]], intense FEL radiation is generated in three gap-tuneable undulator systems called SASE1, SASE2, and SASE3. The electron beam energy of the EXFEL is variable between 8.5 and 17.5 GeV. SASE1 and SASE2 are hard X-ray FELs using planar undulators with a period length of 40 mm, called U40s. By a suitable choice of the beam energy and undulator gap, the wavelength can be tuned from 0.05 to 0.4 nm. SASE3 is a soft X-ray FEL using planar undulators with a period length of 68 mm, called U68s. Under the same conditions, the wavelength can be tuned from 0.4 to 5.2 nm.     

Detectors and Calibration Concept for the European XFEL

The European X-ray Free Electron Laser (XFEL.EU) is an international research facility presently under construction in the area of Hamburg, Germany, which will start its operation at the end of 2016 [1 M. Altarelli, European X-ray Free Electron Laser, European XFEL GmbH, Technical Design Report (2006). [Google Scholar]]. The superconducting linear accelerator of the facility will deliver electron bunches with an energy of up to 17.5 GeV, arranged in trains of typically 2700 bunches at a repetition rate of 4.5 MHz. Each train will be followed by a gap of 99.4 ms. Spatially coherent X-rays are generated from the electron bunches in a series of undulators based on the Self-Amplified Spontaneous Emission (SASE) process, in three photon beamlines extending over a length of up to 200 m. Each beamline serves two experiments with different scientific goals.     

The Evolution of High-Throughput Macromolecular Crystallography at Synchrotrons

On May 11 and 12, 2000, the Stanford Synchrotron Radiation Laboratory, as it was then known, hosted a “Workshop on Techniques for Automated Mounting, Viewing and Centering Pre-Cooled Protein Crystals” [1 http://www-ssrl.slac.stanford.edu/conferences/workshops/px-robotics/. [Google Scholar], 2 E. Abola, Nature Structural Biology 7, 973–977 (2000).[Crossref], [PubMed] , [Google Scholar]]. The 12 presentations during the meeting all focused on the impact that automation could have on the performance of synchrotron beamlines and thus on research in structural biology. Two principal themes ran through the workshop: (1) robotics to mount crystals on a diffractometer; and (2) methods to place a crystal in the X-ray beam. Five conceptual and prototype robotic systems for automated mounting were described—the original ACTOR from Abbott Laboratories, later modified and marketed by Rigaku/MSC, and the systems which in final form become the ALS [3 G. Snell, Structure 12, 537–545 (2004).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]], EMBL/ESRF SC3 [4 F. Cipriani, Acta Cryst. D62(10), 1251–1259 (2006). [Google Scholar]], APS/SBC [5 D. Shu, AIP Conference Proceedings 705(1), 1201–1204 (2004).[Crossref] , [Google Scholar]], and SSRL SAM robots [6 A. E. Cohen, J. Appl. Cryst. 5(6), 720–726 (2002).[Crossref], [Web of Science ®] , [Google Scholar]]. By December of that year, the ACTOR had been installed for testing at Sector 32 of the Advanced Photon Source (Figure 1). Within three years, by the end of 2003, several of these robots, plus the commercial MARcsc from MAR Research, had been deployed to handle frozen protein crystals at beamlines for macromolecular crystallography (MX). Currently, at least 13 distinct robot types, not including variants of the ALS automounter, are employed at synchrotron beamlines to transfer crystals from storage to beam position.     

Undulator Development Towards Very Short Period Lengths

Synchrotron light sources have made progress through the third generation to the fourth generation. Realization of linac-based free electron lasers is a representative example of recent remarkable achievements in fourth-generation light sources. In this progress, there has been a demand to reach shorter wave lengths to expand research possibilities. The on-axis wavelength λ_k of the k-th harmonic of the undulator radiation is given by

Here, K is a deflection parameter proportional to the period length λ_u of the undulator magnetic field and the strength B₀ of a periodic field of the undulator,

At the High Energy Accelerator Research Organization of the Photon Factory (KEK-PF), research and development for in-vacuum undulators have focused on obtaining shorter wavelengths and higher-energy photons. Here, the undulator magnets are contained in the vacuum of the light source accelerator. This method allows one to utilize the shortest period length of the undulator field which can be produced by novel magnet materials provided with the newest magnet technology. The first breakthrough was a successful in-vacuum undulator with a period length of 4 cm, which was installed in the 6.5 GeV Photon Factory-Accumulation Ring (PF-AR) [1 S. Yamamoto, Rev. Sci. Instrum. 63, 400 (1992).[Web of Science ®] , [Google Scholar], 2 S. Yamamoto, J. Appl. Phys., 74, 500 (1993).[Web of Science ®] , [Google Scholar]] for use on the Moessbouer beamline. This was followed by several in-vacuum undulators with the same period length which were installed in the PF-AR, and by several in-vacuum short gap undulators (SGU) installed in the 2.5 GeV PF ring. The latter have period lengths of 1–2 cm and are capable of producing hard X-rays with the third or fifth (or higher) harmonics [3 S. Yamamoto, AIP Conf. Proc., 879, 384 (2007).[Crossref] , [Google Scholar], 4 S. Yamamoto, AIP Conf. Proc., 1234, 599 (2010). [Google Scholar]].     

Flipper: A new instrument for xmcd at the srs

We propose to build at SOLEIL a facility for the accurate measurement of the properties of optical elements and detectors from the extreme ultraviolet (EUV), soft X-ray spectral regions up to the hard X-rays. The beamline will serve as a standard for such measurements and hence we call it a calibration and standards beamline, or alternatively, a metrology beamline. This beamline will also be valuable as a general-purpose beamline to prepare, test and set up a wide range of experiments. A complementary important aspect of this installation is the realization of a primary standard (as in BESSY II) [1 Ulm, G. 2003. Radiometry with synchrotron radiation. Metrologia, 40: S101–S106. [Crossref], [Web of Science ®] , [Google Scholar]]: in this case, the metrology beamline of SOLEIL could become the national primary standard source in collaboration with the Laboratoire National d'Essais (LNE) partner of this project. In another field, this installation will be used in the design and characterization of several diagnostics for the Megajoule Laser in Bordeaux in collaboration with the CEA DIF, also a partner of this project.     

Serial Femtosecond Crystallography

X-ray free-electron lasers produce brief flashes of X-rays that are of about a billion times higher peak brightness than achievable from storage ring sources. Such a tremendous jump in X-ray source capabilities, which came in 2009 when the Linac Coherent Light Source began operations, was unprecedented in the history of X-ray science. Protein structure determination through the method of macromolecular crystallography has consistently benefited from the many increases in source performance from rotating anodes to all generations of synchrotron facilities. But when confronted with the prospects of such bright beams for structural biology, enthusiastic proposals were tempered by trepidation of the effects of such beams on samples and challenges to record data [1 M. Wilmanns, J. Synchr. Rad. 7, 41 (2000).[Crossref], [PubMed] , [Google Scholar]]. A decade after these discussions (and others in the USA) on the applications of X-ray FELs for biology, the first experiments took place at LCLS, giving results that fulfilled many of the dreams of the early visionaries. In particular, the concept that diffraction representing the pristine object could be recorded before the X-ray pulse completely vaporizes the object was validated [2 H.N. Chapman, Nature 470, 73 (2011).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]], confirming predictions [3 R. Neutze, Nature 406, 753 (2000).[Crossref], [Web of Science ®] , [Google Scholar]] that established dose limits could be vastly exceeded using femtosecond-duration pulses. The first experiments illuminated a path to achieve room-temperature structures free of radiation damage, from samples too small to provide useful data at synchrotron facilities, as well as providing the means to carry out time-resolved crystallography at femtoseconds to milliseconds. In the five years since, progress has been substantial and rapid, invigorating the field of macromolecular crystallography [4 J.C.H. Spence and H.N. Chapman, Phi. Trans. Roy. Soc. B 369, 20130309 (2014).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 5 I. Schlichting, IUCrJ 2, 246 (2015).[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]]. This phase of development is far from over, but with both the LCLS and the SPring-8 Ångström Compact Free-electron Laser (SACLA) providing facilities for measurements, the benefits of X-ray FELs are already being translated into new biological insights.