Insertion Device Beamline Research Articles

High-throughput and high-resolution powder X-ray diffractometer consisting of six sets of 2D CdTe detectors with variable sample-to-detector distance and innovative automation system.

The demand for powder X-ray diffraction analysis continues to increase in a variety of scientific fields, as the excellent beam quality of high-brightness synchrotron light sources enables the acquisition of high-quality measurement data with high intensity and angular resolution. Synchrotron powder diffraction has enabled the rapid measurement of many samples and various in situ/operando experiments in nonambient sample environments. To meet the demands for even higher throughput measurements using high-energy X-rays at SPring-8, a high-throughput and high-resolution powder diffraction system has been developed. This system is combined with six sets of two-dimensional (2D) CdTe detectors for high-energy X-rays, and various automation systems, including a system for automatic switching among large sample environmental equipment, have been developed in the third experimental hutch of the insertion device beamline BL13XU at SPring-8. In this diffractometer system, high-brilliance and high-energy X-rays ranging from 16 to 72 keV are available. The powder diffraction data measured under ambient and various nonambient conditions can be analysed using Rietveld refinement and the pair distribution function. Using the 2D CdTe detectors with variable sample-to-detector distance, three types of scan modes have been established: standard, single-step and high-resolution. A major feature is the ability to measure a whole powder pattern with millisecond resolution. Equally important, this system can measure powder diffraction data with high Q exceeding 30 Å-1 within several tens of seconds. This capability is expected to contribute significantly to new research avenues using machine learning and artificial intelligence by utilizing the large amount of data obtained from high-throughput measurements.

Commissioning of a gas monitor detector for an undulator beamline in the VUV and EUV wavelength range

A gas detector system was implemented to monitor the absolute photon flux at the insertion device beamline of the Metrology Light Source. This system should overcome the drawbacks in the use of traceably calibrated semiconductor photodiodes, which are prone to radiation-induced degradation and not qualified for permanent real-time monitoring during the measurements at the beamline endstation. Gas monitor detectors are based on atomic photoionization. They do not suffer from radiation-induced degradation, and their transparency makes them suitable for real-time monitoring of the photon flux. We calibrated and commissioned such a monitor at the insertion device beamline in the vacuum- and extreme ultraviolet spectral range from 14 eV to 111 eV photon energy. The resulting photon flux measurement was compared to measurements made with a photodiode and shows deviations below 5 %, which agrees well with the calculated relative uncertainty of 4.7 %.

Focusing a round coherent beam by spatial filtering the horizontal source.

This paper illustrates the use of spatial filtering with a horizontal slit near the source to enlarge the horizontal coherence in an experimental station and produce a diffraction-limited round focus at an insertion device beamline for X-ray photon correlation spectroscopy experiments. Simple expressions are provided to guide the optical layout, and wave propagation simulations confirm their applicability. The two-dimensional focusing performance of Be compound refractive lenses to produce a round diffraction-limited focus at 11 keV capable of generating a high-contrast speckle pattern of an aerogel sample is demonstrated. The coherent scattering patterns have comparable speckle sizes in both horizontal and vertical directions. The focal spot sizes are consistent with hybrid ray-tracing calculations. Producing a two-dimensional focus on the sample can be helpful to resolve speckle patterns with modern pixel array detectors with high visibility. This scheme has now been in use since 2019 for the 8-ID beamline at the Advanced Photon Source, sharing the undulator beam with two separate beamlines, 8-ID-E and 8-ID-I at 7.35 keV, with increased partially coherent flux, reduced horizontal spot sizes on samples, and good speckle contrast.

Feasibility Study of Upgrades to the PLS-II Storage Ring

The PLS-II is a third-generation light source; it has been operating since 2011. It has a double-bend structure with non-zero dispersion along the straight section. Here, we assess three proposed upgrades to the PLS-II. First, we evaluate use of a canted insertion device beamline to increase the number of beamlines. Second, we evaluate the consequences of upgrading the bending magnet to a superbend magnet; the change doubles the strength of the bending field and increases the critical energy from 8.7 keV to 17 keV. Finally, a short-bunch mode for time-resolved experiments is studied; the goal is to achieve a bunch length of 5 ps rms by using a low-alpha mode and increasing the RF gap voltage.

Compensation of heat load deformations using adaptive optics for the ALS upgrade: a wave optics study.

A realistic wave optics simulation method has been developed to study how wavefront distortions originating from heat load deformations can be corrected using adaptive X-ray optics. Several planned soft X-ray and tender X-ray insertion-device beamlines in the Advanced Light Source upgrade rely on a common design principle. A flat, first mirror intercepts the white beam; vertical focusing is provided by a variable-line-space monochromator; and horizontal focusing comes from a single, pre-figured, adaptive mirror. A variety of scenarios to cope with thermal distortion in the first mirror are studied by finite-element analysis. The degradation of the intensity distribution at the focal plane is analyzed and the adaptive optics that correct it is modeled. The range of correctable wavefront errors across the operating range of the beamlines is reported in terms of mirror curvature and spatial frequencies. The software developed is a one-dimensional wavefront propagation package made availablein the OASYS suite, an adaptable, customizable and efficient beamline modeling platform.

Bubble Formation in the Electrolyte Triggers Voltage Instability in CO2 Electrolyzers.

SummaryThe electrochemical reduction of CO2 is promising for mitigating anthropogenic greenhouse gas emissions; however, voltage instabilities currently inhibit reaching high current densities that are prerequisite for commercialization. Here, for the first time, we elucidate that product gaseous bubble accumulation on the electrode/electrolyte interface is the direct cause of the voltage instability in CO2 electrolyzers. Although bubble formation in water electrolyzers has been extensively studied, we identified that voltage instability caused by bubble formation is unique to CO2 electrolyzers. The appearance of syngas bubbles within the electrolyte at the gas diffusion electrode (GDE)-electrolyte chamber interface (i.e. ∼10% bubble coverage of the GDE surface) was accompanied by voltage oscillations of 60 mV. The presence of syngas in the electrolyte chamber physically inhibited two-phase reaction interfaces, thereby resulting in unstable cell performance. The strategic incorporation of our insights on bubble growth behavior and voltage instability is vital for designing commercially relevant CO2 electrolyzers.

Development of the Beamline Front End at the Pohang Light Source(PLS)-II

The third-generation synchrotron radiation accelerator has been providing beams to users since 1995 and have been made to upgrade the performances of the accelerators and the experimental devices. For that reason, the PLS-II was started in 2009 as a three-year project. An important feature is the extension of the ID (insertion device) beamline and the efficient placement of the storage ring magnet structure. The overall structure of the beamline as well as the length and structure of the front end had to be changed to expand the ID beamline. Also, the safety of many vacuum parts that would be exposed to the large heat due to the increase in the beam energy was firstly considered in the design, and an analysis was performed in parallel. This paper describes the overall structure of the front end, including the design and analysis of the vacuum components in the Pohang Light Source(PLS)-II beamline.

A compact dispersive refocusing Rowland circle X-ray emission spectrometer for laboratory, synchrotron, and XFEL applications.

X-ray emission spectroscopy is emerging as an important complement to x-ray absorption fine structure spectroscopy, providing a characterization of the occupied electronic density of states local to the species of interest. Here, we present details of the design and performance of a compact x-ray emission spectrometer that uses a dispersive refocusing Rowland (DRR) circle geometry to achieve excellent performance for the 2-2.5 keV range, i.e., especially for the K-edge emission from sulfur and phosphorous. The DRR approach allows high energy resolution even for unfocused x-ray sources. This property enables high count rates in laboratory studies, approaching those of insertion-device beamlines at third-generation synchrotrons, despite use of only a low-powered, conventional x-ray tube. The spectrometer, whose overall scale is set by use of a 10-cm diameter Rowland circle and a new small-pixel complementary metal-oxide-semiconductor x-ray camera, is easily portable to synchrotron or x-ray free electron laser beamlines. Photometrics from measurements at the Advanced Light Source show excellent overall instrumental efficiency. In addition, the compact size of this instrument lends itself to future multiplexing to gain large factors in net collection efficiency or its implementation in controlled gas gloveboxes either in the lab or in an endstation.

A monochromatic x-ray irradiation system for in vitro studies at synchrotron beamlines

The use of synchrotron light in radiobiological keV x-ray in vitro studies has been accompanied by compromises in culture conditions and sample handling procedures. The presented monochromatic x-ray system bridges the gap between synchrotron science and cell biology by facilitating the irradiation of adherent cells uninterruptedly maintained under cell type-specific conditions throughout the entire experiment. The system for horizontal irradiations consists of a single crystal Laue monochromator, a beam monitor, and a scanning sample stage. As implemented at the BMIT-BM beamline, the system enables homogeneous cell culture irradiations with intense and purely monochromatic x-ray beams (10–30 keV). The first MCF-7 dose-response study demonstrates how the establishment of a stress-minimized experimental procedure leads to accurate and precise in vitro irradiation results. The cell survival as a function of the surface dose is well described by a first-order exponential decay, indicating that the cellular damage induced by 11.9 keV x-rays is comparable to the lethal effects caused by high linear energy transfer particles. The system design opens up the pathway for combined live-cell imaging and monochromatic keV x-ray applications, while the implementation of the system at insertion device beamlines can help to establish novel investigations on the fundamental role of photonactivation agents in an energy regime up to 100 keV.

Operating synchrotron light sources with a high gain free electron laser

Since the 1980s synchrotron light sources have been considered as drivers of a high repetition rate (RR), high gain free electron laser (FEL) inserted in a by-pass line or in the ring itself. As of today, the high peak current required by the laser is not deemed to be compatible with the standard multi-bunch filling pattern of synchrotrons, and in particular with the operation of insertion device (ID) beamlines. We show that this problem can be overcome by virtue of magnetic bunch length compression in a ring section, and that, after lasing, the beam returns to equilibrium conditions without beam quality disruption. Bunch length compression brings a double advantage: the high peak current stimulates a high gain FEL emission, while the large energy spread makes the beam less sensitive to the FEL heating and to the microwave instability in the ring. The beam’s large energy spread at the undulator is matched to the FEL energy bandwidth through a transverse gradient undulator. Feasibility of lasing at 25 nm is shown for the Elettra synchrotron light source at 1 GeV, and scaling to shorter wavelengths as a function of momentum compaction, beam energy and transverse emittance in higher energy, larger rings is discussed. For the Elettra case study, a low (100 Hz) and a high (463 kHz) FEL RR are considered, corresponding to an average FEL output power at the level of ∼1 W (∼1013 photons per pulse) and ∼300 W (∼1011 photons per pulse), respectively. We also find that, as a by-product of compression, the ∼5 W Renieri’s limit on the average FEL power can be overcome. Our conclusion is that existing and planned synchrotron light sources may be made compatible with this new hybrid IDs-plus-FEL operational mode, with little impact on the standard beamlines functionality.

Beamlines of the biomedical imaging and therapy facility at the Canadian light source – part 3

The BioMedical Imaging and Therapy (BMIT) facility provides synchrotron-specific imaging and radiation therapy capabilities [1–4]. We describe here the Insertion Device (ID) beamline 05ID-2 with the beam terminated in the SOE-1 (Secondary Optical Enclosure) experimental hutch. This endstation is designed for imaging and therapy research primarily in animals ranging in size from mice to humans to horses, as well as tissue specimens including plants. Core research programs include human and animal reproduction, cancer imaging and therapy, spinal cord injury and repair, cardiovascular and lung imaging and disease, bone and cartilage growth and deterioration, mammography, developmental biology, gene expression research as well as the introduction of new imaging methods.The source for the ID beamline is a multi-pole superconducting 4.3T wiggler [5]. The high field gives a critical energy over 20keV. The high critical energy presents shielding challenges and great care must be taken to assess shielding requirements [6–9]. The optics in the POE-1 and POE-3 hutches [4,10] prepare a monochromatic beam that is 22cm wide in the last experimental hutch SOE-1. The double crystal bent-Laue or Bragg monochromator, or the single-crystal K-edge subtraction (KES) monochromator provide an energy range appropriate for imaging studies in animals (20–100+ keV).SOE-1 (excluding the basement structure 4m below the experimental floor) is 6m wide, 5m tall and 10m long with a removable back wall to accommodate installation and removal of the Large Animal Positioning System (LAPS) capable of positioning and manipulating animals as large as a horse [11]. This end-station also includes a unique detector positioner with a vertical travel range of 4.9m which is required for the KES imaging angle range of +12.3° to –7.3°. The detector positioner also includes moveable shielding integrated with the safety shutters.An update on the status of the other two end-stations at BMIT, described in Part 1&2 [3,4] of this article, is included. 1PACS Codes: 07.85.Qe, 07.85.Tt, 87.62.+n, 87.59.–e

Integration and first data with a Pilatus3 6M at APS beamline 23ID-D

GM/CA@APS operates two insertion-device beamlines, 23ID-B and 23ID-D, and one bending magnet beamline, 23BM-B, in sector 23 of the Advanced Photon Source. We recently integrated a Pilatus3 6M detector - a new generation of large sensitive area detectors based on pixel array detector technology and marketed by Dectris. The sensitive area of the device is 423.6 mm × 434.6 mm. The Pilatus3 features the newly implemented re-triggering mechanism that increases the count-rate capabilities by almost an order of magnitude compared to previous generation Pilatus detectors. The detector installed on beamline 23ID-D is the first Pilatus3 6M with a 1000-micron thick sensor, offering higher efficiency at energies above 12 keV. The fast read-out (0.95 ms) and high speed (up to 100 Hz) of the detector allow shutterless data collection. The detector has been fully integrated into the JBluIce user interface and data processing pipeline at GM/CA. Systematic studies with protein crystals were carried out in order to optimize data collection parameters. Overall data collection speed (frame rate), oscillation width per frame, spindle axis speed, and re-triggering have been studied. Different sets of optimal parameters have been established for crystallographic data collection and for crystal screening with the raster feature (grid scanning). The results of these studies and of performance measurements will be presented. This project and GM/CA @ APS are supported by the National Institute of General Medical Sciences and Cancer Institute of NIH.

A Rebirth of Laboratory XANES and XES

We have recently launched a reinvestigation of laboratory-based measurement of x-ray absorption near edge structure (XANES) and high-resolution x-ray emission spectroscopy (XES). Driven by the roughly one-hundred-fold improvement in the efficiency of high resolution x-ray optics compared to the 1970's, we have demonstrated that surprisingly impressive performance is now possible with laboratory XES instruments and that quite useful performance is possible for laboratory XANES. For applications in the 5 keV- 10 keV energy range, i.e., appropriate for 3d transition metal K edges and lanthanide L edges, we find XES performance that is intermediate between what can be achieved at bending-magnet and insertion-device beamlines at third generation synchrotron light sources. In the same energy range, we find that high quality XANES measurements can be performed in transmission mode on concentrated samples with the present instrument and should be possible, in many cases, in fluorescence mode after a planned upgrade brings the monochromatic beam flux up to approximately 10M/sec.

Automated High-Throughput Data Collection at IMCA-CAT

The Industrial Macromolecular Crystallography Association Collaborative Access Team (IMCA-CAT) operates a data collection facility at the Advanced Photon Source for protein crystallography. IMCA-CAT meets the demands of IMCA member pharmaceutical companies for reliable, high-quality, high-throughput data collection, while ensuring a secure environment for proprietary research. The 17ID micro-focused high-flux insertion device beamline, equipped with a Pilatus 6M pixel array detector, allows for very fast data collection times. The focused beam size (30 μm x 70 μm) can be easily optimized for each sample using a GM/CA-CAT mini-beam quad collimator, with user-selectable beam sizes of 50, 20, 10 and 5 μm. An Alio goniometer has a small (1.2 μm) sphere of confusion, providing stable sample positioning, and X-ray beam position is maintained within 2 μm by custom software in real time. Automated sample mounting is performed with a Rigaku ACTOR robot, accepting both Rigaku and ALS/Unipuck style magazines, providing fast yet reliable sample exchanges and enabling remote access and unattended data collection. Rigaku JDirector software for robot control and data collection has been customized to incorporate additional tools, such as diffraction-based sample centering for both manual and unattended data collection modes, vector data collection and inverse beam anomalous data collection. While targeting the needs of industrial research, the automation and rapid data collection times at 17ID are also ideally suited for structural genomics and other research efforts requiring high-throughput experiments. Access is available to interested researchers through the APS General User Program and through subscription memberships for those needing regular and guaranteed proprietary beamtime.

Exploiting coherence for real-time studies by single-bunch imaging.

First real-time studies of ultra-fast processes by single-bunch imaging at the European Synchrotron Radiation Facility are reported. By operating the storage ring of the ESRF in single-bunch mode with its correspondingly increased electron bunch charge density per singlet, the polychromatic photon flux density at insertion-device beamlines is sufficient to capture hard X-ray images exploiting the light from a single bunch (the corresponding bunch length is 140 ps FWHM). Hard X-ray imaging with absorption contrast as well as phase contrast in combination with large propagation distances is demonstrated using spatial samplings of 11 µm and 35 µm pixel size. The images acquired allow one to track crack propagation in a bursting piece of glass, breaking of an electrical fuse as well as cell wall rupture in an aqueous foam. Future developments and their potential in the frame of the proposed Phase II of the ESRF Upgrade Program are discussed.

A synchrotron-radiation-based variable angle ellipsometer for the visible to vacuum ultraviolet spectral range.

A rotating analyzer spectroscopic polarimeter and ellipsometer with a wide-range θ-2θ goniometer installed at the Insertion Device Beamline of the Metrology Light Source in Berlin is presented. With a combination of transmission- and reflection-based polarizing elements and the inherent degree of polarization of the undulator radiation, this ellipsometer is able to cover photon energies from about 2 eV up to 40 eV. Additionally, a new compensator design based on a CaF2 Fresnel rhomb is presented. This compensator allows ellipsometric measurements with circular polarization in the vacuum ultraviolet spectral range and thus, for example, the characterization of depolarizing samples. The new instrument was initially used for the characterization of the polarization of the beamline. The technical capabilities of the ellipsometer are demonstrated by a cohesive wide-range measurement of the dielectric function of epitaxially grown ZnO.

Macromolecular crystallography beamline X25 at the NSLS.

Beamline X25 at the NSLS is one of the five beamlines dedicated to macromolecular crystallography operated by the Brookhaven National Laboratory Macromolecular Crystallography Research Resource group. This mini-gap insertion-device beamline has seen constant upgrades for the last seven years in order to achieve mini-beam capability down to 20 µm × 20 µm. All major components beginning with the radiation source, and continuing along the beamline and its experimental hutch, have changed to produce a state-of-the-art facility for the scientific community.

Performance Prediction for a Hockey-Puck Silicon Crystal Monochromator at the Advanced Photon Source

One of the Key Performance Parameters of the upgrade of the Advanced Photon Source (APS) is the increase of the storage ring current from 100 to 150 mA. In order to anticipate the impact of this increased heat load on the X-ray optics of the beamlines, the APS has implemented a systematic review, by means of finite element analysis and computational fluid dynamics, of the thermal performance of the different types of monochromators installed at the highest-heat-load insertion device beamlines. We present here simulations of the performance of a directly liquid nitrogen-cooled silicon crystal, the hockey-puck design. Calculations of the temperature and slope error at multiple ring currents under multiple operational conditions, including the influence of power, cooling, and diffraction surface thickness are included.

Supplemental shielding of BMIT SOE-1 at the Canadian Light Source

High field superconducting wiggler beamlines present shielding challenges due to the high critical energy of the synchrotron spectrum. An unexpected, but predictable, weakness in the secondary optical enclosure (SOE-1) was discovered on the BioMedical Imaging and Therapy (BMIT) insertion device (ID) beamline 05ID-2 at the Canadian Light Source (CLS). SOE-1 is a monochromatic beam hutch; the beam in it is supplied by three monochromators housed in an upstream primary optical enclosure (POE-3). The initial shielding of SOE-1 was based on a shielding calculation against target scattered and direct monochromatic (fundamental and harmonics) beams from the monochromators in POE-3. During a radiation survey of the hutch, radiation above the expected level was measured at the downstream end of SOE-1. This increment in radiation level is attributed to scattered white beam into SOE-1 by a K-Edge subtraction (KES) monochromator׳s crystal (a single crystal monochromator) in POE-3. Though this is peculiar to the BMIT beamline 05ID-2, it may not be uncommon for other beamlines that use single crystal monochromators.Calculations of the level of expected leakage radiation due to the scattered white beam arriving on the downstream wall of the SOE-1 are presented, as well as the supplemental shielding that will reduce the leakage to less than 1μSv/h as required at the CLS. Also presented are the installed supplemental shielding, and a comparison of the calculations and measurements of the dose rates on the back wall of SOE-1 End Wall, before and after installation of the supplemental shielding.

Upgrade of Pohang Light Source (PLS-II) and Challenge to PAL XFEL

In December 10, 2010, the Pohang Light Source (PLS) permanently stopped its operation. The PLS was the first third-generation light source in Korea and operated for 15 years. The PLS energy was 2.5 GeV. With strong user requests to increase the number of high-quality insertion device (ID) beamlines and to further improve beam quality of the PLS, the Pohang Accelerator Laboratory (PAL) started a new project in 2009 to convert the old PLS to a new and advanced third-generation light source, PLS-II [1]. The PLS-II project period and budget were three years from 2009 and US $100 M. The project was successfully completed on time and within budget in 2011. The PLS-II fully opened its door to users on March 21, 2012.