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The SYRMA-CT project aims to set-up the first clinical trial of phase-contrast breast Computed Tomography with synchrotron radiation at the SYRMEP beamline of Elettra, the Italian synchrotron light source. The challenge in a dedicated breast CT is to match a high spatial resolution with a low dose level. In order to fulfil these requirements, the SYRMA-CT project uses a large area CdTe single photon counting detector (Pixirad-8), simultaneous algebraic reconstruction technique (SART) and phase retrieval pre-processing. This work investigates the imaging performances of the system in a continuous acquisition mode and with a low dose level towards the clinical application. A custom test object and a large surgical sample have been studied.

A planar permanent magnet undulator based beamline for atomic, molecular and optical science research is proposed on Indus-2, a third generation synchrotron light source, at Raja Ramanna Centre for Advanced Technology, Indore, India. A varied line spacing plane grating monochromator in a converging beam and constant included angle mode is used for obtaining monochromatic light in this beamline. This monochromator contains a toroidal focusing mirror and four interchangeable gratings in a new orientation to disperse photons in the energy range of 6–250 eV. We have obtained resolving powers ~104. Details of the methodology followed in evaluation of new mounting proposed for varied line spacing plane grating monochromator, preparation and optimization of beamline optical layout, imaging properties, resolution attainable and intensity at sample position are presented in this paper.

The design of the MAX IV 3 GeV ultralow-emittance storage ring is presented and the implementation of solutions to the technological challenges imposed by the compact multi-bend achromat lattice are described., The MAX IV facility, currently under construction in Lund, Sweden, features two electron storage rings operated at 3 GeV and 1.5 GeV and optimized for the hard X-ray and soft X-ray/VUV spectral ranges, respectively. A 3 GeV linear accelerator serves as a full-energy injector into both rings as well as a driver for a short-pulse facility, in which undulators produce X-ray pulses as short as 100 fs. The 3 GeV ring employs a multibend achromat (MBA) lattice to achieve, in a relatively short circumference of 528 m, a bare lattice emittance of 0.33 nm rad, which reduces to 0.2 nm rad as insertion devices are added. The engineering implementation of the MBA lattice raises several technological problems. The large number of strong magnets per achromat calls for a compact design featuring small-gap combined-function magnets grouped into cells and sharing a common iron yoke. The small apertures lead to a low-conductance vacuum chamber design that relies on the chamber itself as a distributed copper absorber for the heat deposited by synchrotron radiation, while non-evaporable getter (NEG) coating provides for reduced photodesorption yields and distributed pumping. Finally, a low main frequency (100 MHz) is chosen for the RF system yielding long bunches, which are further elongated by passively operated third-harmonic Landau cavities, thus alleviating collective effects, both coherent (e.g. resistive wall instabilities) and incoherent (intrabeam scattering). In this paper, we focus on the MAX IV 3 GeV ring and present the lattice design as well as the engineering solutions to the challenges inherent to such a design. As the first realisation of a light source based on the MBA concept, the MAX IV 3 GeV ring offers an opportunity for validation of concepts that are likely to be essential ingredients of future diffraction-limited light sources.

The first proposed lattice for a ‘diffraction-limited light source’ is reported. This approach has now more or less been used for the MAX IV project., By the beginning of 1990, three third-generation synchrotron light sources had been successfully commissioned in Grenoble, Berkeley and Trieste (ESRF, ALS and ELETTRA). Each of these new machines reached their target specifications without any significant problems. In parallel, already at that time discussions were underway regarding the next generation, the ‘diffraction-limited light source (DLSR)’, which featured sub-nm rad electron beam emittance, photon beam brilliance exceeding 1022 and the potential to emit coherent radiation. Also, at about that time, a first design for a 3 GeV DLSR was developed, based on a modified multiple-bend achromat (MBA) design leading to a lattice with normalized emittance of ∊x = 0.5 nm rad. The novel feature of the MBA lattice was the use of seven vertically focusing bend magnets with different bending angles throughout the achromat cell to keep the radiation integrals and resulting beam emittance low. The baseline design called for a 400 m ring circumference with 12 straight sections of 6 m length. The dynamic aperture behaviour of the DLSR lattice was estimated to produce > 5 h beam lifetime at 100 mA stored beam current.

For a future synchrotron light source based on a linac, e.g. an X-ray free electron laser and an energy recovery linac (ERL), an injector is a key component to generate a high brightness electron beam. For the acceleration and transportation of the electron beam in the injector, the adjustment of beam orbit inside the cavity is important to avoid the deterioration of the beam quality due to the transverse electric field of it, which causes the transverse emittance growth. To adjust the beam orbit, an investigation of the electromagnetic center of the cavity is required in the beam operation. This paper shows a new method for measuring the electromagnetic center of the cavity, and describes an analytical model of emittance growth due to a combination of transverse electric field and orbit offset. The validation of the method was confirmed by the emittance measurement in the compact ERL (cERL) injector at KEK.

A staggered undulator with high-temperature superconducting bulks might be a solution to achieve an undulator with an extremely short period for a synchrotron light source. YBCO bulk was thus selected to investigate the feasibility. This bulk (diameter 32 mm, thickness 2.5 mm) was used to build a staggered-magnet array structure and a mock-up staggered undulator of period 5 mm and fixed gap 4 mm was designed for this test. The potential generation of a sinusoidal field was tested in a 3-T magnetization system with field-cooling magnetization (FCM). The practicability of a HTS undulator is discussed in regard to the possibility of correction of the local field, repetition of field trapping and long-term stability. In addition, a field simulation concept was developed for designing the staggered undulator with YBCO bulks.

The experimental application of a novel technique utilizing a high resolution 2D pixel detector (PILATUS) in scanning transmission X-ray microscopy is presented. Measurements were performed at beamline P11 at the PETRA III synchrotron light source. Results are compared to the approach based on a segmented-type detector. A full simulation of the experimental line has been implemented in C++ programming language. Concepts of ptychography and its application in X-ray microscopy are also brie y discussed.

Over the three decades since the feasibility study for the establishment of the Taiwan Light Source (TLS) in 1981, the National Synchrotron Radiation Research Center (NSRRC) has evolved into a well-known light source facility. With rapid advances in the international scientific community, as well as increasing demands for bright X-rays from users to facilitate their challenging scientific experiments, a point was reached at which the construction of a new synchrotron facility was vital to ensuring that NSRRC remained globally competitive. After conducting numerous assessments with our users, the decision to construct the Taiwan Photon Source (TPS) was made at a board meeting held in July 2004. This large-scale project will establish, at the current campus of NSRRC, a new, low-emittance, synchrotron light source of circumference 518 m and with an electron beam of energy 3 GeV.

ALBA is a low-emittance, 3 GeV synchrotron light source located near Barcelona. It is funded equally by the Spanish central and the Catalan autonomous governments. Seven state-of-the-art beamlines (BL), comprising soft and hard X-rays, are in operation to satisfy the requirements of the user community. This paper updates the status of the facility, focusing on its transition from commissioning to user operation, which has taken place during the last two years.

New methods are needed to rapidly identify malaria parasites in blood smears. The coupling of a Focal Plane Array (FPA) infrared microscope system to a synchrotron light source at IRENI enables rapid molecular imaging at high spatial resolution. The technique, in combination with hyper-spectral processing, enables imaging and diagnosis of early stage malaria parasites at the single cell level in a blood smear. The method relies on the detection of distinct lipid signatures associated with the different stages of the malaria parasite and utilises resonant Mie extended multiplicative scatter correction to pre-process the spectra followed by full bandwidth image deconvolution to resolve the single cells. This work demonstrates the potential of focal plane technology to diagnose single cells in a blood smear. Brighter laboratory based infrared sources, optical refinements and higher sensitive detectors will soon see the emergence of focal plane array imaging in the clinical environment.

Transverse beam coupling impedance is a source of beam instabilities that limits the machine performance in circular accelerators. Several beam based techniques have been used to measure the transverse impedance of an accelerator, usually based on the optics distortion produced by the impedance source itself. Beam position monitor turn-by-turn analysis for impedance characterization has been usually employed in large circumference machines, while synchrotron light sources have mainly used slow orbit based techniques. Instead, the work presented in this paper uses for the first time turn-by-turn data at ALBA to advance the measurement technique into the range of the typically small impedance values of modern light sources. We have measured local impedance contributions through the observation of phase advance versus bunch charge using the betatron oscillations excited with a fast dipole kicker. The ALBA beam position monitor system and the precision of the turn-by-turn analysis allowed to characterize the main sources of transverse impedance, in good agreement with the model values, including the impedance of an in-vacuum undulator.

Coherent light sources are one of the most fundamental research tools in biology, technology and in other areas. Synchrotron light source consists of a few basic parts: energy source – which is an electron beam accelerator, energy converter between electron and photon beams – which is an undulator, and photon user experimental lines. Each of these parts is separately a complex system, which is currently a subject to fast technological development. Future light sources of the fifth generation are based on completely new solutions of these fundamental parts, in comparison with the sources of the previous generations. Energy source is a new generation laser – plasma accelerator with electrical field in the area of multiple GV/m. A miniature undulator is tested in the MEMS technology from new materials. Classical light beam lines, vacuum, and difficult for management and beam distribution, change their meaning in the case of availability of miniature undulators positioned immediately at or even inside the experimental stations. After an introduction concerning the light sources of the previous generations, the article shows current research efforts on the mentioned key components of the fifth generation light sources. In some cases this is a continuation and modernization of the previous technologies, in the majority it is a brave endeavour to apply completely new technologies, like laser – plasma acceleration.

Beam emittance reduction is an effective method to increase the brightness of a synchrotron light source. Robinson wiggler can play a role in the beam emittance reduction by increasing the horizontal damping partition number. A replacement of the quadrupoles in the arc section with short combined function dipoles will construct a single-periodic Robinson wiggler in the SSRF storage ring. This scheme provides a lower beam emittance, without occupying any straight section. Detailed analysis is presented in this paper.

La contaminación del medio hídrico por metales pesados y metaloides (en adelante metales) en solución puede estar asociado potencialmente al drenaje ácido de mina (AMD, de las siglas en inglés de Acid Mine Drainage) o a los lixiviados procedentes de suelos sulfatados ácidos (ASS, de las siglas en inglés de Acid Sulfate Soils). Tanto el AMD como el ASS procede de la exposición y oxidación de los sulfuras presentes en depósitos minerales o en suelos desarrollados en condiciones reducidas, respectivamente. En ambos casos, la oxidación de sulfuras, principalmente pirita, libera protones, sulfato, hierro ferroso y otros metales, reduciendo el pH e incrementando la carga iónica en solución. Esta contaminación es atenuada por la precipitación de fases nanominerales tales como schwertmannita y basaluminita. Las características estructurales de schwertmannita y su afinidad por los contaminantes se han estudiado previamente en profundidad; sin embargo, poco se sabe aún sobre basaluminita. Así, el principal objetivo de esta Tesis Doctoral es proponer un modelo estructural para basaluminita y estudiar su capacidad para retener contaminantes por medio de técnicas no convencionales basadas en radiación sincrotrón (por ejemplo difracción de rayos-X de alta energía y Absorción de rayos-X en estructura fina). 1) En primer lugar, se realizaron experimentos de neutralización con un agua ácida reducida en condiciones atmosféricas y anóxicas para determinar, por separado, la capacidad de retención de elementos trazas en schwertmannita y basaluminita. Bajo condiciones atmosféricas, la precipitación inicial de schwertmannita condujo a la retirada total de Fe, As, Pb y Cr de la solución, enmascarando el posible potencial de la basaluminita en los procesos de atenuación, como ocurre en condiciones naturales. Sin embargo, en condiciones anóxicas, la neutralización de la solución reducida con el hierro en solución causó la precipitación inicial de basaluminita, demostrando una elevada afinidad de esta fase, no descrita anteriormente, por As y Cr. 2) En segundo lugar, se realizaron experimentos de isotermas de adsorción para cuantificar la capacidad máxima de adsorción de As y Se en schwertmannita y basaluminita sintéticas, así como el efecto competitivo del sulfato por los sitios de adsorción superficial. Además, se emplearon técnicas basadas en radiación sincrotrón para determinar la coordinación local de los complejos de As y Se en ambas estructuras. Los resultados mostraron que el intercambio de oxianiones entre sulfato estructural y As o Se en solución fue el mecanismo principal de retención. La capacidad máxima de adsorción de As en basaluminita fue dos veces mayor que en schwertmannita y tres veces mayor al Se en ambas fases. La presencia de sulfato en solución no afectó a la adsorción de As, pero sí tuvo un fuerte impacto en la retirada de Se. Los resultados de sincrotrón mostraron que el tipo de coordinación más probable para As en ambas fases y Se en schwertmannita fue el complejo bidentado binucleado de esfera interna, mientras que Se en basaluminita se sitúa en posición de esfera externa. 3) Finalmente, se realizaron experimentos de sincrotrón y modelos de simulación Monte Cario para determinar la estructura de rango corto de la basaluminita. Este nanomineral mostró altos contenidos en sulfatos en diferentes posiciones estructurales entre muestras naturales (esfera externa) y sintéticas (esfera interna). Ambas muestras de basaluminita tuvieron idéntico orden local con un dominio coherente de 1.2 nm. Por otro lado, el Al en basaluminita mostró características similares a los A1I3 con estructura keggin, con ~1% y 5% de Al en coordinación tetraèdrica y pentaédrica, respectivamente. De acuerdo con los modelos estructurales, la basaluminita presentó fuertes similitudes a la felsobányaita, la cual estuvo formada por capas de Al octaédrico con posiciones vacantes y una alta distorsión angular y longitudinal de los octaedros, donde el sulfato y el agua se aloja en los espacios entre capas. En conclusión, esta Tesis Doctoral describe la basaluminita como un nanomineral estratégico en la movilidad de metales en áreas afectadas por AMD y ASS, y su estudio ha permitido entender mejor los procesos de atenuación natural que ocurren en sistemas afectados por oxidación de sulfuros. Esta información ayudará también a mejorar la eficiencia de los sistemas de tratamiento y a plantear nuevas estrategias enfocadas a la recuperación de metales con interés económico., The pollution of the aquatic environment by heavy metals and metalloids (from now on referred as ‘metals’) in solution can be potentially associated with acid mine drainage (AMD) or with leachates from acid sulfate soils (ASS). Both AMD and ASS derive from the exposition and oxidation of sulfide minerals contained in mineral ore bodies or in soils formed under reducing conditions,, respectively. In both cases, sulfide oxidation, mainly pyrite, releases protons, sulfate, ferrous iron and other metals; reducing the pH and increasing the ionic load in the solution. This pollution is attenuated by precipitation of nanominerals such as schwertmannite and basaluminite. The schwertmannite structural framework and its affinity by metals have been previously studied in depth, whereas little is known about basaluminite. Thus, the main objective of this doctoral dissertation is to propone a structural model for basaluminite and to study its properties as scavenger of toxic elements by means of non-conventional techniques based on synchrotron radiation (e.g. High Energy X-ray Diffraction and X-ray absorption fine structure). 1) Firstly, neutralization experiments were conducted using a naturally reduced AMD with all aqueous Fe as Fe(II) under atmospheric and anoxic conditions to elucidate, individually, the sorption capacity of trace elements in solution by schwertmannite and basaluminite. Under atmospheric conditions, initial precipitation of schwertmannite led to the total removal of Fe, As, Cr and Pb in solution, masking the possible basaluminite affinity by these elements, as occurs in natural systems. However, under anoxic conditions, neutralization of the reduced solution with all Fe available in solution led first to the basaluminite precipitation, unveiling a heretofore unknown affinity of this phase for As and Cr. 2) Secondly, adsorption isotherm experiments were conducted to quantify the maximum As and Se adsorption capacities on synthetic schwertmannite and basaluminite, as well as the sulfate competitive effect for surface sorption sites. In addition, synchrotron-based techniques were used to determine the local coordination of As and Se complexes in both structural frameworks. The results showed that oxyanion exchange between structural sulfate and As or Se in solution was the main removal mechanism. Maximum As adsorption capacity by basaluminite was twice higher than by schwertmannite and three times higher than Se by both phases. The presence of sulfate had little effect on the sorption As capacity; although it had a strong negative effect on Se removal. Synchrotron results indicated that bidentate binuclear inner-sphere was the most probable ligand for As on both phases and for Se on schwertmannite, whereas Se formed outer-sphere complexes in basaluminite. 3) Finally, synchrotron experiments and reverse Monte Carlo analysis were performed to determine the short-range structure of basaluminite. This nanomineral showed high sulfate contents with different structural coordination between natural (outer-sphere position) and synthetic (inner-sphere position) samples. Both synthetic and natural basaluminites had identical local order with 1.2 nm of coherent domain. On the other hand, A1 in basaluminite showed similar features to Ali3 keggin ions with -1% and 5% of tetrahedral and pentahedral coordination, respectively. According to the structural models, basaluminite revealed similar structural framework to felsobanyaite, which was formed by octahedral A1 layers layers with vacant positions and high angular and longitudinal octahedral distortion, where sulfate and water molecules were emplace in the interlayer space. In conclusion, this doctoral dissertation describes basaluminite as a strategic nanomineral on the metals behavior in areas affected by AMD and ASS, and its study has allowed better understand the natural attenuation processes occurring in systems affected by sulfide oxidation. This information will help also to improve the efficiency of the treatment systems and to develop new strategies focused on metal recovery with economic interest.

The majority of the beamlines at the Brazilian Synchrotron Light Source Laboratory (LNLS) use radiation produced in the storage-ring bending magnets and are therefore currently limited in the flux that can be used in the harder part of the X-ray spectrum (above ~ 10 keV). A 4 T superconducting multipolar wiggler (SCW) was recently installed at LNLS in order to improve the photon flux above 10 keV and fulfill the demands set by the materials science community. A new multi-purpose beamline was then installed at the LNLS using the SCW as a photon source. The XDS is a flexible beamline operating in the energy range between 5 and 30 keV, designed to perform experiments using absorption, diffraction and scattering techniques. Most of the work performed at the XDS beamline concentrates on X-ray absorption spectroscopy at energies above 18 keV and high-resolution diffraction experiments. More recently, new setups and photon-hungry experiments such as total X-ray scattering, X-ray diffraction under high pressures, resonant X-ray emission spectroscopy, among others, have started to become routine at XDS. Here, the XDS beamline characteristics, performance and a few new experimental possibilities are described. Fil: Lima, Frederico Alves. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Saleta, Martin Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Pagliuca, Rafael José dos Santos. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Eleotério, Marcos Antônio. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Reis, Ricardo D.. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Fonseca Júnior, Jairo. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Meyer, Bernd. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Bittar, Eduardo Matzenbacher. Centro Brasileiro de Pesquisas Físicas; Brasil Fil: Souza Neto, Narcizo Marques. Laboratorio Nacional de Luz Sincrotron; Brasil Fil: Granado, Eduardo. Universidade de Campinas; Brasil

A low-frequency superconducting cavity is needed in main accelerators for storage ring light sources with ultralow emittance. A compact 166.6 MHz superconducting proof-of-principle cavity was designed adopting a quarter-wave β = 1 geometry for a High Energy Photon Source (HEPS). It is a 6 GeV diffraction-limited synchrotron light source currently being developed at the Institute of High Energy Physics. The cavity is exceedingly compact in size yet possessing a low resonant frequency. The nearest higher order mode is largely separated from the fundamental, making the cavity an attractive geometry for effective damping of these modes in high current accelerators such as HEPS. The achieved accelerating voltage of 3.0 MV is well beyond the designed 1.5 MV and required 1.2 MV for HEPS operation. High surface electromagnetic fields were reached with excellent rf and mechanical performances, and multipacting barriers were easily processed. This constitutes the first demonstration of a compact low-frequency β = 1 superconducting cavity for HEPS. The design, fabrication, surface preparation, and cryogenic tests of the cavity are presented.

Zehra Sayers won a science-diplomacy award for her role in setting up the region’s first synchrotron light source. Zehra Sayers won a science-diplomacy award for her role in setting up the region’s first synchrotron light source.

SOLEIL, a 2.75 GeV third-generation synchrotron light source [1], 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 European XFEL and DESY Photon Science Annual Users' Meeting 2013 set a new record: more than 800 participants, scientists, staff, and students from 25 countries registered for this event. The three-day meeting took place from January 23 to 25, 2013, at DESY in Hamburg (Germany). There was great interest in the latest news on the construction of the European XFEL and on the extension projects at PETRA III and FLASH, and the participants had plenty of opportunities to catch up on recent free-electron laser (FEL) and synchrotron light source developments ranging from THz to hard X-rays applications.

Injection into the two MAX IV storage rings will not make use of a 4-kicker local injection bump. Instead, pulsed multipole injection will be used for initial filling as well as top-up injection. Since commissioning a pulsed multipole magnet for injection into a storage ring is non-trivial, it has been decided to install a single dipole kicker magnet into the storage rings to provide a simple method for injection during early commissioning. Design studies have revealed that injection with a single dipole kicker into the MAX IV storage rings is not only efficient, but also allows for accumulation of beam. Although this accumulation cannot be made transparent to users (i.e. it is not compatible with user top-up operation), it does provide a simple and robust injection method during commissioning. In addition, the dipole kicker can be used as a pinger magnet during machine studies with a single-bunch filling. This paper reports on the design studies performed for dipole kicker injection into the MAX IV storage rings and presents a summary of the expected performance of such an injection scheme.

Using arbitrary periodic pulse patterns we show the enhancement of specific frequencies in a frequency comb. The envelope of a regular frequency comb originates from equally spaced, identical pulses and mimics the single pulse spectrum. We investigated spectra originating from the periodic emission of pulse trains with gaps and individual pulse heights, which are commonly observed, for example, at high-repetition-rate free electron lasers, high power lasers, and synchrotrons. The ANKA synchrotron light source was filled with defined patterns of short electron bunches generating coherent synchrotron radiation in the terahertz range. We resolved the intensities of the frequency comb around 0.258 THz using the heterodyne mixing spectroscopy with a resolution of down to 1 Hz and provide a comprehensive theoretical description. Adjusting the electron's revolution frequency, a gapless spectrum can be recorded, improving the resolution by up to 7 and 5 orders of magnitude compared to FTIR and recent heterodyne measurements, respectively. The results imply avenues to optimize and increase the signal-to-noise ratio of specific frequencies in the emitted synchrotron radiation spectrum to enable novel ultrahigh resolution spectroscopy and metrology applications from the terahertz to the x-ray region.

In this report, AI-BL1.0, an open-source Labview-based program for automatic on-line beamline optimization, is presented. The optimization algorithms used in the program are Genetic Algorithm and Differential Evolution. Efficiency was improved by use of a strategy known as Observer Mode for Evolutionary Algorithm. The program was constructed and validated at the XAFCA beamline of the Singapore Synchrotron Light Source and 1W1B beamline of the Beijing Synchrotron Radiation Facility.

The optical design of the BOREAS beamline operating at the ALBA synchrotron radiation facility is described. BOREAS is dedicated to resonant X-ray absorption and scattering experiments using soft X-rays, in an unusually extended photon energy range from 80 to above 4000 eV, and with full polarization control. Its optical scheme includes a fixed-included-angle, variable-line-spacing grating monochromator and a pair of refocusing mirrors, equipped with benders, in a Kirkpatrick–Baez arrangement. It is equipped with two end-stations, one for X-ray magnetic circular dichroism and the other for resonant magnetic scattering. The commissioning results show that the expected beamline performance is achieved both in terms of energy resolution and of photon flux at the sample position.

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e− electronic noise charge (, Journal of Synchrotron Radiation, 23 (2), ISSN:0909-0495, ISSN:1600-5775

Im Rahmen dieser Dissertation wird die Stärke der Multibunch-Instabilität (MBI), die von longitudinalen Dipol-, transversalen Dipol- und Quadrupolschwingungsmoden höherer Ordnung getrieben werden mithilfe von analytischen Rechnungen und Trackingsimulationen in dem Ausbauprojekt BESSY Variable Pulse Length Storage Ring (BESSY VSR) des Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB) untersucht und mit dem vorhanden aktiven Dämpfungssystem verglichen. Algorithmen für Trackingsimulationen werden hergeleitet und eine halbempirische Formel zur Abschätzung der transversalen quadrupolaren MBI wird präsentiert. MBI Studien bilden einen wesentlichen Teil der Beurteilung der BESSY VSR Hohlraumresonatoren und begleiteten und beeinflussten ihren Entwicklungsprozess. Mit Berechnungen auf Grundlage des neusten BESSY VSR Hohlraumresonatormodels kann Strahlstabilität als wahrscheinlich und unabhängig vom Füllmuster angesehen werden. Des weiteren wurden Messungen der MBI an BESSY II und der Metrology Light Source (MLS) der Physikalisch-Technischen Bundesanstalt durchgeführt, bei welcher die longitudinale langreichende Impedanz charakterisiert wurde. Transiente Strahllast wird in dieser Arbeit mit analytischen Formeln und neuen, experimentell überprüften Trackingsimulationen berechnet. Für das Standardfüllmuster von BESSY VSR wurde gezeigt, dass die besondere Konfiguration der Hohlraumresonatorfrequenzen zu einer relativ starken Beeinflussung der langen Elektronenpakete führt. Diese verkürzt das Elektronenpaket und vergrößert die Touschekverluste. In the scope of this thesis, the strength of coupled bunch instabilities (CBIs) driven by longitudinal monopole higher order modes (HOMs) and transverse dipole and quadrupole HOMs is evaluated for the upgrade project BESSY Variable Pulse Length Storage Ring (BESSY VSR) at Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), based on analytic calculations and tracking simulations, and compared to the performance of an active bunch-by-bunch feedback (BBFB). Algorithms for tracking codes are derived, and a semi-empirical formula for the estimation of transverse quadrupole CBIs is presented. CBI studies are an integral part of the benchmarking of the cavity models for BESSY VSR and have been accompanying and influencing their entire design process. Based on the BESSY VSR cavity model with highly advanced HOM damping, beam stability is likely to be reached with a BBFB system, independent of the bunch fill pattern. Additionally, measurements of CBIs have been performed at BESSY II and the Metrology Light Source of the Physikalisch-Technische Bundesanstalt (MLS), where the longitudinal long range impedance was characterized. Transient beam loading is evaluated by means of analytic formulas and new experimentally verified tracking codes. For the baseline bunch fill pattern of BESSY VSR, it is shown that the particular setup of cavity frequencies amplifies the transient effect on the long bunch, limiting its elongation and potentially resulting in increased Touschek losses.

The current status of the TwinMic beamline at Elettra synchrotron light source, that hosts the European twin X-ray microscopy station, is reported. The X-ray source, provided by a short hybrid undulator with source size and divergence intermediate between bending magnets and conventional undulators, is energy-tailored using a collimated plane-grating monochromator. The TwinMic spectromicroscopy experimental station combines scanning and full-field imaging in a single instrument, with contrast modes such as absorption, differential phase, interference and darkfield. The implementation of coherent diffractive imaging modalities and ptychography is ongoing. Typically, scanning transmission X-ray microscopy images are simultaneously collected in transmission and differential phase contrast and can be complemented by chemical and elemental analysis using across-absorption-edge imaging, X-ray absorption near-edge structure or low-energy X-ray fluorescence. The lateral resolutions depend on the particular imaging and contrast mode chosen. The TwinMic range of applications covers diverse research fields such as biology, biochemistry, medicine, pharmacology, environment, geochemistry, food, agriculture and materials science. They will be illustrated in the paper with representative results.

X-ray phase and dark-field imaging techniques provide complementary and inaccessible information compared to conventional X-ray absorption or visible light imaging. However, such methods typically require sophisticated experimental apparatus or X-ray beams with specific properties. Recently, an X-ray speckle-based technique has shown great potential for X-ray phase and dark-field imaging using a simple experimental arrangement. However, it still suffers from either poor resolution or the time consuming process of collecting a large number of images. To overcome these limitations, in this report we demonstrate that absorption, dark-field, phase contrast and two orthogonal differential phase contrast images can simultaneously be generated by scanning a piece of abrasive paper in only one direction. We propose a novel theoretical approach to quantitatively extract the above five images by utilising the remarkable properties of speckles. Importantly, the technique has been extended from a synchrotron light source to utilise a lab-based microfocus X-ray source and flat panel detector. Removing the need to raster the optics in two directions significantly reduces the acquisition time and absorbed dose, which can be of vital importance for many biological samples. This new imaging method could potentially provide a breakthrough for numerous practical imaging applications in biomedical research and materials science.

We report on a high resolution sapphire backscattering monochromator installed at the Dynamics beamline P01 of PETRA III. The device enables nuclear resonance scattering experiments on Mössbauer isotopes with transition energies between 20 and 60 keV with sub-meV to meV resolution. In a first performance test with $^{119}$Sn nuclear resonance at a X-ray energy of 23.88 keV an energy resolution of 1.34 meV was achieved. Thedevice extends the field of nuclear resonance scattering at the PETRA III synchrotron light source to many further isotopes like $^{151}$Eu, $^{149}$Sm, $^{161}$Dy, $^{125}$Te and $^{121}$Sb.

The photon-ion merged-beams technique was used at a synchrotron light source for measuring absolute cross sections of double and triple photodetachment of O$^{-}$ ions. The experimental photon energy range of 524-543 eV comprised the threshold for K-shell ionization. Using resolving powers of up to 13,000, the position, strength and width of the below-threshold 1s 2s2 2p6 2S resonance as well as the positions of the 1s 2s2 2p5 3P and 1s 2s2 2p5 1P thresholds for K-shell ionization were determined with high precision. In addition, systematically enlarged multi-configuration Dirac-Fock calculations have been performed for the resonant detachment cross sections. Results from these ab-initio computations agree very well with the measurements for the widths and branching fractions for double and triple detachment, if double shake-up (and -down) of the valence electrons and the rearrangement of the electron density is taken into account. For the absolute cross sections, however, a previously found discrepancy between measurements and theory is confirmed., Comment: 5 pages, 2 figures

This chapter serves as introduction to particle accelerators used in medicine. Many types of particle accelerator were built for nuclear and particle physics research and most of them have also found some use in medicine, mainly in treatment of cancer with ionizing radiation. Two categories of particle accelerator are known: electrostatic based on charged particle acceleration with electrostatic fields and cyclic based on particle acceleration with electromagnetic fields. The chapter is devoted to a brief discussion of machines used in charged particle acceleration and production of ionizing radiation beams for use in medicine. The chapter starts with x-ray tubes: (Crookes, Coolidge, and carbon nanotube) and continues with brief descriptions of betatron, cyclotron, microtron, synchrotron, and synchrotron light source. The last section of the chapter deals with clinical linear accelerator, the principal machine of modern radiotherapy.

A new cryogen-free full scale (1.5 m long) superconducting undulator with a period length of 15 mm (SCU15) has been successfully tested in the ANKA storage ring. This represents a very important milestone in the development of superconducting undulators for third and fourth generation light sources carried on by the collaboration between the Karlsruhe Institute of Technology and the industrial partner Babcock Noell GmbH. SCU15 is the first full length device worldwide that with beam reaches a higher peak field than what expected with the same geometry (vacuum gap and period length) with an ideal cryogenic permanent magnet undulator built with the best material available PrFeB. After a summary on the design and main parameters of the device, we present here the characterization in terms of spectral properties and the long term operation of the SCU15 in the ANKA storage ring.

Time-resolved experimental techniques are increasingly abundant at storage ring facilities. Recent developments in accelerator technology and beamline instrumentation allow for simultaneous operation of high-intensity and timing-based experiments. The MAX IV facility is a state-of-the-art synchrotron light source in Lund, Sweden, that will come into operation in 2016. As many storage ring facilities are pursuing upgrade programs employing strong-focusing multibend achromats and passive harmonic cavities (HCs) in high-current operation, it is of broad interest to study the accelerator and instrumentation developments required to enable timing-based experiments at such machines. In particular, the use of hybrid filling modes combined with pulse picking by resonant excitation or pseudo single bunch has shown promising results. These methods can be combined with novel beamline instrumentation, such as choppers and instrument gating. In this paper we discuss how these techniques can be implemented and employed at MAX IV.

The NSLS-II Synchrotron Light Source is a 3GeV electron storage ring recently commissioned and is now entering operations at Brookhaven National Laboratory. One of the major tasks was to commission the six project beamline front ends which required a diagnostic to resolve x-ray beam position for the purpose of beam alignment at low current. Since none of the front ends were outfitted with any x-ray diagnostics in the baseline design, an x-ray beam profile monitor or “flag” that could be easily installed into existing front end vacuum chambers was proposed to satisfy this requirement. Here we present the development of this novel device which utilizes a polycrystalline CVD diamond luminescent screen to produce a visible image of the x-ray beam cross-section and is then captured with a CCD camera.

ALBA is a 3GeV synchrotron light source located in Barcelona. Currently it has 7 beamlines fully operational since 2012. Currently, the design of new beamlines has started, and up to 8 have been priorized. Two of them (Phase II) are currently under construction phase (2014-2018). Only one insertion device is foreseen for this phase, namely, an aperiodic helical undulator. The specificities of foreseen applications, specially the capability to reject high harmonics, lead to two possible technical solutions: aperiodic Apple-II or Electromagnetic. Both are presented in this paper. The Phase III will be built according to the funding allowance. Five of them have IDs as light sources. Regarding phase-III beamlines, they include In-vacuum undulators, very narrow gap undulators (

In early stages of various pulmonary diseases, such as emphysema and fibrosis, the change in X-ray attenuation is not detectable with absorption-based radiography. To monitor the morphological changes that the alveoli network undergoes in the progression of these diseases, we propose using the dark-field signal, which is related to small-angle scattering in the sample. Combined with the absorption-based image, the dark-field signal enables better discrimination between healthy and emphysematous lung tissue in a mouse model. All measurements have been performed at 36 keV using a monochromatic laser-driven miniature synchrotron X-ray source (Compact Light Source). In this paper we present grating-based dark-field images of emphysematous vs. healthy lung tissue, where the strong dependence of the dark-field signal on mean alveolar size leads to improved diagnosis of emphysema in lung radiographs.

Summary Leaf venation networks mediate many plant resource fluxes and are therefore of broad interest to research questions in plant physiology, systematics, paleoecology, and physics. However, the study of these networks is limited by slow and destructive imaging methods. X-ray imaging of leaf veins is potentially rapid, of high resolution, and nondestructive. Here, we have developed theory for absorption- and phase-contrast X-ray imaging. We then experimentally test these approaches using a synchrotron light source and two commercially available X-ray instruments. Using synchrotron light, we found that major veins could be consistently visualized using absorption-contrast imaging with X-ray energies

The basics and experimental details of transmission radiation techniques in the application to conservation of wooden cultural objects are described. Standard and synchrotron X-rays, as well as neutrons, can provide very useful options for the non-invasive analysis of the wood structure, its conservation state and the influence of wood treatment in the conservation and decontamination process. The working and application range specific to each kind of radiation is discussed. Although X-ray methods (standard tube systems and synchrotron light source facilities) can cover a wide range in object size and wood density, neutrons can be used preferentially to study and quantify substances with high hydrogen content (moisture, resin, glues, wax) inside the wooden structure. Several examples chosen from studies performed within COST Action IE0601 illustrate the results that can be obtained using these techniques and their combination. The need for further studies using the performances available at large-scale facilities is discussed as a way to establish routine approaches for wood conservation and museums objects.

MIRRORCLE generates brilliant far-infrared, extreme ultraviolet, and hard X-ray beams in a body of tabletop electron storage ring (ESR). In this paper, we report the most recent development of the 4- and 1-MeV, 8-cm orbit radius ESR. X-rays are generated in Bremsstrahlung mechanism by a micron-order ball shape target placed in the ESR electron orbit. Nature of the source is different from either X-ray tubes or synchrotron light sources (SLS). MIRRORCLE generates high-density photons such as SLS, but the emitter size is much smaller than that. The X-ray angular distribution is 1/γ determined by the normalized electron energy γ, thus is much wider than of SLS with the MeV electrons. The energy spectrum is polychromatic like SLS but continues up to MeV range. MIRRORCLE has advantages in magnified phase contrast X-ray 2D and 3D imaging for light as well as heavy materials. It has an advantage in fluorescent analysis of micron-sized objects because focus size is in microns. It is advanced in an ultrasmall-angle scattering experiment by its micron-order focus point. Extended X-ray absorption fine structure is carried out in an energy dispersive mode because of the white spectrum and the wide angular spread of radiation. Copyright © 2012 John Wiley & Sons, Ltd.

A new model of quadrupole composed of permanent magnetic material, coils and soft magnetic material is proposed for the new Brazilian Synchrotron Light Source (Sirius). These quadrupoles must have flexibility about 30% of the total gradient in order to correct the linear effects caused by the insertion devices on the beam dynamics. This flexibility is obtained using coils while permanent magnets are used to supply the constant gradient.

The imaging methods used at the ANKA Synchrotron Light Source (Institute for Synchrotron Radiation, Karlsruhe Institute of Technology) are briefly reviewed. Examples of recent applications of the phase-contrast imaging method using a grating interferometer and fast radiography with optic flow data analysis to study static and moving biological objects are presented.

A one-dimensional diffusion model of the Diamond Light Source storage ring vacuum system is described and its predictions are compared with actual measured static (without beam) and dynamic (with beam) pressures over more than 2000 A h of beam conditioning at 3 GeV. An average specific thermal outgassing yield of 1·10 −11 mbar l/(s cm 2 ) during initial beam circulation is obtained, which reduces to 2·10 −12 mbar l/(s cm 2 ) after an accumulated beam dose of 1000 A h and an elapsed time of 769 days. In the presence of stored electron beam, the pressure rises as expected due to photon stimulated desorption (PSD). The PSD yield reduces with beam dose according to a (−2/3) power law as was applied in the model. Predicted and measured dynamic pressures generally agree within a factor of 2 over the whole range of beam conditioning dose studied.

Taiwan Photon Source is a third-generation 3-GeV synchrotron light source under construction. The electron storage ring of circumference 518.4 m contains 24 unit cells and 24 long straight sections. Each cell of length about 14 m contains two bending chambers and two short straight chambers. To estimate the pressure distribution in the cell vacuum system, a program combining an iterative method and a Monte-Carlo method was used to calculate the pressure. In the modeling, the rate of thermal outgassing of the chamber surfaces and the yield of photon-stimulated desorption of the absorbers are obtained from the experimental results. To provide the effective pumping speed of various pumps that depends on the gas, the composition of residual gases from photon-stimulated desorption was assumed to be 80% H2 and 20% CO. The pressure calculation for the vacuum cell compares the beam cleaning efficiency during the early commissioning stage when the accumulated beam dose attained 1 A h and 100 A h. The effects of the confined pumping design are evaluated through the modeling to assess whether the commissioning can be accelerated. The result of the pressure calculation obtained with the Monte-Carlo method shows that a mean pressure rise per beam current at 1.9 � 10