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Insertion into delicate tissue, such as retina vein occlusion, cell manipulation and vitreoretinal injection, poses challenges to surgeons and biomedical researchers due to the high resolution, large movement range, compact structure and multi-DOF output requirements. In order to meet these requirements, a 2-DOF arched needle insertion device driven by inertial piezoelectric actuator was proposed in this work. This device could perform theoretical unlimited translational movement and full rotation with high step resolution. A prototype was fabricated with compact structure, the length and diameter were 230 mm and 32 mm, respectively. The experimental tests were carried out, the insertion device output 2.47 m and 0.56 mrad step distance with maximum velocity of 382 m/s and 200.9 mrad/s under 120 V driving signals, the maximum insertion force of 32 mN was measured. Additionally, a handheld controller with friendly user interface was also developed for open-loop control utilization, which could automatically calculate and generate the required control signals according to the motion command. This device explores the biomedical application of inertial piezoelectric actuator within a compact size, providing a new choice for numerous innovative treatment and biological research involving precision operation.

Undulators as the sources of high-brilliance synchrotron radiation are of widespread interest in new generations of light sources and free-electron lasers. Microwave propagation in a plasma-filled elliptical waveguide can be studied as a standard short-period undulator. This structure as a lucrative insertion device can be installed in the storage ring of third- and fourth-generation light sources to produce high-energy and high-brilliance synchrotron radiation. In this article, the propagation of the transverse electric modes in a plasma-filled waveguide with an elliptical cross-section is investigated, and the field components, the cut-off frequencies and the electron beam trajectory are calculated. With due consideration of the electron beam dynamics and in order to achieve a standard short-period undulator, parameters such as the dimensions of the waveguide elliptical cross-section, the microwave frequency and the plasma density are calculated.

High energy photon source (HEPS) is the fourth-generation light source, which uses a large number of high-performance insertion devices to generate synchrotron radiation. The control system is an important part of the insertion device (ID). Cryogenic permanent magnet undulator (CPMU) is one kind of IDs that works in liquid nitrogen temperature and ultra-high vacuum environment, and its control system is more difficult and complex than in-air ID. The design of the control system for CPMU will be introduced in detail. The sub-systems include high-precision magnetic gap control, safety protection, measurement and compensation of magnetic gap at cryogenic temperature and cryogenic temperature monitoring. Mature, reliable, stable technical schemes are designed to meet the technical specifications of sub-systems. The experiment results show that the magnetic gap motion accuracy can be controlled within 0.2–0.3 μm under the step size of 1 μm. The safety protection system has been tested in turn, and the predetermined protection can be achieved. The average value of magnetic gap cold contraction is 1.512 mm measured by optical micrometer, and the compensation is realized by software. The average temperature of the main magnet structure measured by the temperature sensors is 81.0 K, and the temperature gradient is 0.7 K/m. The temperature monitoring is reliable and stable. The CPMU control system which is based on EPICS has been successfully applied to the CPMU prototype, and the test results have met the design specifications.

Fourth-generation storage rings (4GSR) based on multi-bend achromat (MBA) lattices promise to deliver stable X-ray beams with higher brightness and coherence than existing third-generation light sources. The basic ingredient in achieving higher brightness is a further reduction of the electron beam emittance in storage rings dedicated to light sources. These 4GSR lattices can lead to 1 to 2 orders of magnitude reductions in the beam emittance by employing a MBA, where many dipoles per cell are used to keep the dispersion function low inside the dipoles. Moreover, these low emittance beams are transported to the beam-line through the insertion device or center-bend, which is a permanent magnet with a 2 T magnetic field. In this paper, we will introduce the characteristics of the synchrotron radiation of 4GSR compared to present third-generation sources, PLS-II.

Radiation damage has been a known problem at many synchrotron radiations and free-electron lasers facilities, especially those that use hybrid or pure permanent magnet undulators to produce high brightness light. Field strength loss due to demagnetization makes it necessary to remove the insertion device from the tunnel for inspection and repair, which brings several inconveniences. We aimed to develop an in situ radiation damage detection system for undulators capable of diagnosing relative field changes of 10−4 (100 ppm) or smaller. The system measures the flux change in a flexible printed circuit board coil attached to the undulator magnet array by periodically measuring the integral flux change during the opening and closing of the undulator gap. If the magnet block damage occurs, the signal from the coil will decrease proportionally to the damage. First tests performed on variable gap hybrid undulators for the Linac Coherent Light Source II (LCLS-II) at SLAC National Accelerator Laboratory showed that the system is capable of measuring flux changes with a relative precision of approximately $0.7 \times 10^{-4}$ over several days. Relative field changes smaller than 10−4 were detected in short-term measurements. The novel system that we propose here opens the possibility of detecting radiation damage in undulators during operation.

A hybrid cryogenic permanent-magnet undulator (CPMU) with a 15-mm period length is being constructed for a TPS Phase-II beamline. A control system for this CPMU (CU15) is under development since 2018 and is based on the Experimental Physics and Industrial Control System (EPICS) architecture and Ethernet Control Automation Technology (EtherCAT) framework. The main control components include a motor with encoder for gap adjustment, corrector magnet power supplies, ion pumps and BA gauges for the vacuum system, resistance temperature detectors (RTD) and heaters for temperature control of the cryogenic environment and magnet arrays, motion safety interlock, cryogenic system and vibration monitor system. The design and implementation of the CU15 control system will be summarized in this paper.

An Insertion Device (ID) is a key component of synchrotron radiation source and free electron laser. It is a periodic arrangement of diploe magnets according to Halbach rule. The precision fabrication and measurement of the ID is a crucial factor to the performance of the radiation source. A standard procedure is to measure the magnetic field quality from Hall probe measurement bench and analyze the data to extract information on phase error, field integral and straightness of the electron beam passing through the device. In this paper we report a user-friendly MATLAB code to analyze the Hall probe data. The code is used on data collected from one meter long undulator installed at Insertion Device application and Laser Instrumentation Laboratory at Devi Ahilya University, Indore, Madhya Pradesh, India.

The refrigerant flow distribution in the parallel flow microchannel evaporators is experimentally investigated to study the effect of header configuration. Six different configurations are tested in the same evaporator by installing insertion device and partition plate in the header to ensure the consistency of the other structure parameters. The results show that the uniformity of refrigerant flow distribution and the heat transfer rate are greatly improved by reducing the sectional area of header. The heat transfer rate can increase by 67.93% by reducing the sectional area of both inlet and outlet headers. The uniformity of refrigerant flow distribution and the heat transfer rate become worse after installing the partition plate in the insertion devices and changing the inner structure of the header further.

A superconducting wiggler with a magnetic field of 7 T is installed as an insertion device for three X-ray beamlines with photon energies of more than 30 keV used at the Dortmund Electron Accelerator (DELTA, Germany), a source of 1.5 GeV synchrotron radiation. Each of the two side beamlines is separated from the central one by 15 mrad and all three beamlines use a horizontal aperture of 5 mrad. To meet these requirements, the insertion device must have a period of 127 mm and a magnetic field of 7 T for the vertical aperture of a beam vacuum chamber 10 mm long and a flange-to-flange distance of 2.2 m. A superconducting 22-pole wiggler with a field of 7 T and a period of 127 mm operating in the zero boil-off mode is described. The concept and main approaches to designing the magnetic and the cryogenic systems are presented, along with the main parameters and results from testing the new 7-tesla superconducting wiggler for the DELTA storage ring.

We have discussed a versatile three-color IR-FEL scheme as an insertion device for Iranian light source facility which can works in three different wavelengths in the range of infrared spectrum. Three output wavelengths are regarded in tune with the electron beam parameters at the exit of three linacs of the ILSF pre-accelerator section. Studies have been done in the context of a 1D numerical method governing the nonlinear dynamics of a single-pass FEL. The characteristics of the FEL output corresponding to three different electron beam energies have been presented and discussed.

A cantilevered liquid-nitrogen-cooled silicon mirror is described that will achieve diffraction-limited performance even under extreme power density. This mirror will serve as a robust first optic for the high-brightness undulator beamlines at the upgraded Advanced Light Source., This paper presents a novel cantilevered liquid-nitro­gen-cooled silicon mirror design for the first optic in a new soft X-ray beamline that is being developed as part of the Advanced Light Source Upgrade (ALS-U) (Lawrence Berkeley National Laboratory, USA). The beamline is optimized for photon energies between 400 and 1400 eV with full polarization control. Calculations indicate that, without correction, this design will achieve a Strehl ratio greater than 0.85 for the entire energy and polarization ranges of the beamline. With a correction achieved by moving the focus 7.5 mm upstream, the minimum Strehl ratio is 0.99. This design is currently the baseline plan for all new ALS-U insertion device beamlines.

The process of tyre removal as it is being done in developing economies before repair and replacement after repair requires so much human effort and is prone to accident. This article reports the development and testing of an improved technology which is a modification on the existing technology for bead breaking, tyre removal and insertion which overcomes a significant percentage of the drawbacks of the technology currently in use. The development considered the ease of operation, direction of application of force and the amplification of input effort. Performance evaluation was carried out for tyre of rim sizes 14 and 15 inches and the results show that the overall time taken for the entire bead breaking and tyre insertion process is shorter than that required for conventional bead breaking device.

The upgrade of the Advanced Light Source at Lawrence Berkeley National Lab to a Diffraction-Limited Storage Ring (DLSR) will feature four new and upgraded beamlines, designed to take full advantage of the coherence and high brightness of the insertion device source operating mostly in the soft x-ray regime (100–2000 eV). The round and highly coherent beam drives specific design choices for the photon transport optics and monochromator, and technical challenges in terms of performances, optical tolerances and stability. We have used the simulation tools Shadow (for raytracing) or SRW (wavefront propagation), and their implementation in OASYS and Sirepo to refine tolerance specifications, using their scripting capabilities and new add-ons to perform a comprehensive beamline analysis and confirm that specifications matched our performance requirements, taking into account partial coherence and issues related to heatload.

This study is trying to design the thermal load effect on the soft x-ray beamline first mirror from ID (Insertion Device). The beamline first mirror is HFM (Horizontal Focus Mirror), the HFM need to absorb the thermal energy, soft X-ray the footprint size om HFM is 120*5.2 mm, the thermal power is about 270 W. The HFM cooling by the water pipe mounted on the thermal fin, mirror and thermal fin contact by Gallium–Indium alloy. The HFM thermal fin's Gallium–Indium alloy seal by nickel tube avoids leaking in the vacuum chamber. The HFM thermal fin design can cooling mirror backside and part of frontside, and the HFM thermal bump need small than 10u rad.

In this paper we provide an update on the development of a novel cantilevered-liquid-nitrogen-cooled-silicon mirror for a new insertion device beamline included in the Advanced Light Source Upgrade (ALS-U). The goals of this mirror development are to achieve diffraction limited performance, demonstrate reliability, minimize coolant flow induced vibration, and demonstrate carbon contamination prevention and cleaning techniques. In this paper we summarize the design requirements, the design of the mirror system, and prototype fabrication.

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.

Measuring a magnetic field by applying electric current to a wire in a magnetic field for a short duration and recording the resulting travelling wave is referred to as the pulsed wire method. This technique is beneficial when other methods for acquiring magnetic field data are not feasible, e.g. small aperture limit of a Hall probe to measure an insertion device, or it can be used as a complement to other techniques. Data collected during pulsed wire measurements require corrections due to dispersion of the travelling wave and averaging effects of the current pulse duration. A flexible method for correcting dispersion has been developed using all pass digital filtering techniques and deconvolution is used to correct for pulse width averaging. Implementing the correction method is described along with the results of measuring a reference magnet and a 2.4-meter long undulator.

The Taiwan Photon Source Front End (TPS FE) vacuum systems are located between the storage ring and beam lines and include various high-heat-load (HHL) components. We investigate the change in dynamic pressure over time in the FE vacuum system, including measurements of HHL component temperatures, residual gas analyzer (RGA) data analysis, and the effect of changing the insertion device (ID) gap during beam current operation. Our results reveal that the exponential slopes of dynamic pressures in the FE versus accumulated beam dose is nearly −0.5 for all cases. With beam current at 400 mA and ID gap close to 7 mm, the dynamic pressure and HHL component temperature are 1.5 × 10−8 Pa and 45 °C, respectively. The RGA data show that the main dynamic pressure contributions are H2, H2O, CO and CO2. H2O, CO and CO2 come from the chamber surface, while H2 comes from the vacuum chamber materials. The dynamic pressure was ∼2.3 × 10−11 Pa/mA at 1000 Ah, and it continues to decrease with an increase in accumulated beam dose. These results indicate that the total dynamic pressure reaches to a value of 10−7 Pa at full operation current in the FE systems.

The first cryogenic permanent-magnet undulator installed at National Synchrotron Radiation Research Center (NSRRC) suffered in the first year from an issue of a high operating temperature. Two bulged transition tapers were identified as possible sources for the large heat load. The profile modeling of the upstream transition taper enabled an estimate of the parasitic heating power, and indicated the cause of the large heat load. Simultaneously, one longitudinal instability was observed when the stored beam current of the TPS storage ring was 500 mA. A corresponding study of the longitudinal coupled-bunch instability induced by the resonance mode of the bulged transition tapers has been undertaken. The simulation results indicated that the longitudinal coupled-bunch instability would become damped by the radiation damping of the accelerator. The newly constructed transition tapers with a new design of the tapers significantly decrease the parasitic heating power. This study focuses on the impacts on beam dynamics of the electron storage ring resulting from the cavity-like structure.

X-ray microprobes (XRM) coupled with high-brightness synchrotron X-ray facilities are powerful tools for environmental biogeochemistry research. One such instrument, the XRM at the Geo Soil Enviro Center for Advanced Radiation Sources Sector 13 at the Advanced Photon Source (APS; Argonne National Laboratory, Lemont, IL) was recently improved as part of a canted undulator geometry upgrade of the insertion device port, effectively doubling the available undulator beam time and extending the operating energy of the branch supporting the XRM down to the sulfur K edge (2.3 keV). Capabilities include rapid, high-resolution, elemental imaging including fluorescence microtomography, microscale X-ray absorption fine structure spectroscopy including sulfur K edge capability, and microscale X-ray diffraction. These capabilities are advantageous for (i) two-dimensional elemental mapping of relatively large samples at high resolution, with the dwell times typically limited only by the count times needed to obtain usable counting statistics for low concentration elements, (ii) three-dimensional imaging of internal elemental distributions in fragile hydrated specimens, such as biological tissues, avoiding the need for physical slicing, (iii) spatially resolved speciation determinations of contaminants in environmental materials, and (iv) identification of contaminant host phases. In this paper, we describe the XRM instrumentation, techniques, applications demonstrating these capabilities, and prospects for further improvements associated with the proposed upgrade of the APS.

Users of HEPS require polarization adjustable and high-flux synchrotron radiation with energy of 100–2000 eV. To achieve 100 eV photon energy at HEPS, a 6 GeV storage ring, the problem of on-axis heat load becomes a significant challenge for users. A new type of four-row merged APPLE–Knot undulator recently proposed seems to be the most effective solution to reduce on-axis power density. However, as an undulator with such complex magnetization orientation distribution of magnetic blocks, its field integrals correction and the effect of field errors on the radiation performance are different from that of conventional EPU. Whether it can realize its field integrals correction and perform as well as in theory with field errors has become a concern. Here, a set of field integrals correction schemes is reported and field errors analysis has been done. A general method for evaluating the effect of magnetization orientation deviation of the magnetic block on radiation performance is proposed. It can be used for any insertion device containing permanent magnetic magnets if necessary.

As an insertion device, the superconducting wiggler has been developed for about 40 years, the superconducting magnet of which is usually made of NbTi and set in a cryostat. The performance of the cryostat is vital to the success of the superconducting wiggler. In this paper, a cryostat of the superconducting wiggler with 32 poles and 2.6 T field for the High Energy Photon Source Test Facility (HEPS-TF) was developed in the Institute of High Energy Physics (IHEP). In the cryostat, a novel design of thermal structure and cooling capacity distribution was proposed. Compared with the conventional two thermal shields, the single thermal shield was adopted to simplify the mechanical design, which was extended to the outside of the vacuum chamber to decrease the heat loads at 4.2 K. The current leads were optimized to minimize the heat loads at 60 K. After the systematic thermal analysis and optimization, the total heat load was covered by the four Gifford-Mcmahon cryocoolers successfully. In the experiment, the measured heat load was 3.85 W with magnet current of 320 A and beam of 250 mA. And the residual cooling power was 0.65 W.

It is shown that an extensive set of accurate ionization-chamber measurements with a primary polychromatic synchrotron X-ray beam transmitted through various filter combinations/thicknesses can be used to quite effectively estimate the absolute flux distribution. The basic technique is simple but the `inversion' of the raw data to extract the flux distribution is a fundamentally ill-posed problem. It is demonstrated, using data collected at the Imaging and Medical Beamline (IMBL) of the Australian Synchrotron, that the absolute flux can be quickly and reliably estimated if a suitable choice of filters is made. Results are presented as a function of the magnetic field (from 1.40 to 4.00 T) of the superconducting multi-pole wiggler insertion device installed at IMBL. A non-linear least-squares refinement of the data is used to estimate the incident flux distribution and then comparison is made with calculations from the programsSPECTRA,XOPandspec.exe. The technique described is important not only in estimating flux itself but also for a variety of other, derived, X-ray properties such as beam quality, power density and absorbed-dose rate. The applicability of the technique with a monochromatic X-ray beam for which there is significant harmonic contamination is also demonstrated. Whilst absolute results can also be derived in this monochromatic beam case, relative (integrated) flux values are sufficient for our primary aim of establishing reliable determinations of the percentages of the various harmonic components.

© 2018 Ultra-flexible electrode arrays with a cross-sectional area of only a few μm² show great promise for long-term, high resolution neural interfacing without detrimental scar tissue formation. However, due to their low stiffness, insertion is a challenge. In this work, we investigate microneedles consisting of quickly biodegradable, short-chained, acid terminated PLGA (50:50 lactide:glycolide ratio) as insertion device for a polyimide-based neural electrode array of 1 μm thickness. An upscalable, wafer-level fabrication process is presented. Both separate PLGA microneedles as well as complete, assembled neural probes were tested in vivo for up to 4 months. The arrays allowed to record spontaneous spike activity and evoked local field potentials in the somatosensory cortex of rats on all measured timepoints. Very limited lesion formation, measuring about 20% of the cross sectional area of the original microneedle, was observed. Neurons can be seen to infiltrate the area originally taken up by the dissolving PLGA microneedle. The results indicate that the presented electrode arrays and insertion method are well suitable for application in long-term, high resolution neural recording. ispartof: Sensors And Actuators B-Chemical vol:284 pages:369-376 status: published

We present a system for scalable and customizable recording and stimulation of neural activity. In large animals and humans, the current benchmark for high spatial and temporal resolution neural interfaces are fixed arrays of wire or silicon electrodes inserted into the parenchyma of the brain. However, probes that are large and stiff enough to penetrate the brain have been shown to cause acute and chronic damage and inflammation, which limits their longevity, stability, and yield. One approach to this problem is to separate the requirements of the insertion device, which should to be as stiff as possible, with the implanted device, which should be as small and flexible as possible. Here, we demonstrate the feasibility and scalability of this approach with a system incorporating fine and flexible thin-film polymer probes, a fine and stiff insertion needle, and a robotic insertion machine. Together the system permits rapid and precise implantation of probes, each individually targeted to avoid observable vasculature and to attain diverse anatomical targets. As an initial demonstration of this system, we implanted arrays of electrodes in rat somatosensory cortex, recorded extracellular action potentials from them, and obtained histological images of the tissue response. This approach points the way toward a new generation of scaleable, stable, and safe neural interfaces, both for the basic scientific study of brain function and for clinical applications.

Brain machine interfaces notoriously face difficulties in achieving long term implanted recording stability. It has been shown that damage and inflammation, caused during insertion by electrodes that are too large and stiff, provoke a sustained inflammatory tissue response. This is commonly referred to as the foreign body response, resulting in encapsulation and thus increased electrode impedance over time. Accordingly, neural interfaces with ever smaller and more flexible electrodes are continually in development, but unfortunately face challenges of their own, first and foremost of which is buckling and bending during insertion. This work presents the development of a prototype insertion method, comprising an insertion device and novel probe architecture, that promotes straight insertion without buckling, while simultaneously minimizing the insertion force for multi-microwire electrode probes. When compared against insertion of probes with unsupported free electrodes, the prototype method achieved significantly straighter electrode insertion, resulting in both a smaller distance between electrode recording tips and a greater average insertion depth. While achieving less straight insertion than probes with sucrose coated electrodes, a common technique for promoting reliable insertion without buckling, the tested method was able to maintain significantly lower insertion forces.

The aim of this study was to evaluate the effect of three different macrodesigns and two different insertion devices on the accuracy of static computer-assisted implant surgery (sCAIS).Ninety implant replicas with three different macrodesigns: Soft tissue level (TL), bone level (BL), and bone level tapered (BLT) were placed in 30 dental models with two implant insertion devices: Guided adapter and guided screwed-in mount. Preoperative and postoperative positions of implants were compared and the mean angular deviation, crestal, and apical three-dimensional (3D) deviation were calculated for each implant macrodesign and each insertion device. Data were analyzed using analysis of variance, post hoc t-tests and Bonferroni-Holm's adjustment method. P values less than .05 were considered statistically significant.BLT implants had lower mean 3D deviation values at the crest and the apex when compared with 3D deviations with BL and TL implants (P .05). Also, BLT implants had lower angular deviations, when compared with BL and TL Implants, however, angular deviations were not statistically significant (P .05). Considering the insertion device method, no significant differences were noted between insertion devices irrespective of the deviation analyzed.The macrodesign of dental implants may have an influence on the accuracy of sCAIS, with tapered designs offering slightly better positional accuracy than parallel-walled macrodesigns independent on the method of insertion used.

Small gap wigglers become more and more attractive to produce high photon fluxes in the hard X-ray photon range. They use magnet blocks of high magnetization which resists much better to heating (baking, synchrotron radiation) than in the past, produce high magnetic field with numerous periods and are very compact. They also are a very good alternative to superconducting technology which requires special infrastructure, heavy maintenance and is not running cost free. SOLEIL, operating presently at 2.75 GeV has designed and built an in-vacuum wiggler of 38 periods of 50 mm producing 2.1 T at a minimum gap of 5.5 mm to delivered photon beam between 20 keV and 50 keV. Already in operation, further improvements are presently in progress to push photons towards higher energy, in particular thanks to the operation at lower gap (4.5 mm). MAX IV and SOLEIL, in the frame of collaboration, ave built an upgraded version of the existing SOLEIL wiggler with the target to extend the spectral range at high energy (above 50 keV) but also at low energy (4 keV) with the same insertion device. The design of the existing magnetic system has been modified to reach 2.4 T at a minimum gap of 4.2 mm and includes taper operation to avoid undulator structure in the radiated spectrum at low energy. (Less)

Overshooting trocar insertion in Iaparoscopic surgery has been extensively cited as a major cause of surgical injury. The complexity and extensive insertion force required of the current handheld insertion method increases the risk of overshooting and is difficult for novice and female operators. Hence, we developed a trocar insertion device to make the procedure easier and safer. The device is designed so it is easy to handle and assemble. It used negative pressure and pneumatic cylinders to lift the abdominal wall and two motors to drive the trocar insertion. In addition, we interpreted the characteristics of the insertion force and developed an algorithm to detect whether the trocar is properly inserted. By monitoring changes in the insertion force with this device, the trocar insertion can be stopped automatically and immediately. The development of this device has realized the automation of trocar insertion. It reduces the demand on operators and improves the safety of the procedure.

To supply a high flux of full adjustable polarization synchrotron radiation with low on-axis power density for users of HEPS, a new type of pure permanent magnetic (PPM) undulator structure called delta–knot has been proposed. The physical design of a prototype of a 3-period cryogenic delta–knot undulator is presented herein. It can achieve a maximum 1.6 T peak magnetic field with a periodic length of 40 mm using PrFeB material at 80 K. Specifications of the main magnetic structure as well as the field performances and radiation spectra at arbitrary polarization modes are also obtained. It is demonstrated that the on axis power density is significantly reduced in any polarization mode except the 45° incline polarization mode.

The Pohang Accelerator Laboratory’s X-ray free-electron laser (PAL-XFEL), a 4th generation light source, is currently being installed and will be completed by December 2015 so that users can be supported beginning in 2016. The PAL-XFEL equipment must continuously maintain the bunch-tobunch beam parameters (60 Hz, Energy: 10 GeV, Charge: 200 pC, Bunch Length: 60 fs, Emittance X/Y: 0.481/0.256 mm rad) in order to supply stable photons with the energy and flux appropriate for tests by beamline users. To this end, the PAL-XFEL equipment has to be kept precisely aligned (Linear Accelerator: +/− 100 μm, Undulator: +/− 50 μm). As a part of the process for installing the PAL-XFEL, a GPS-using surface geodetic network is being constructed for precise equipment measurement and alignment, and the installation of a tunnel measurement network inside the buildings is in the preparation stage; additionally, the fiducialization of major equipment is underway. After the PAL-XFEL equipment is optimized and aligned, if the ground and the buildings go through vertical changes during operation, misalignment (and tilt) of the equipment, including various magnets and RF structures, will cause errors in the electron beam’s trajectory, which will lead to changes to the beam parameters. For continuous and systemic measurement of vertical changes in the buildings and monitoring of ground sinking and uplifting, the Budker Institute of Nuclear Physics (BINP) Ultrasonic-type Hydrostatic Levelling System (HLS) is to be installed and operated in all sections of the PAL-XFEL for the linear accelerator, the insertion device (undulator) and the beamline. This study will introduce the operation principle, design concept, and advantages (self-calibration) of the HLS and will outline its installation plan and operation plan.

An insertion device (ID) is a crucial component in a third-generation synchrotron light source, which produces highly brilliant, forward-directed, and quasi-monochromatic radiation over a broad energy range. The Taiwan Photon Source (TPS) project involves building another synchrotron light source with increased electron energy. In phase I of TPS, seven in-vacuum undulators with magnetic period 22 mm (IU22) were installed; commissioning is in process. The control system for IU22 is based on an EPICS framework. The main control components include motors with encoders for gap adjustment, trimming power supplies for corrector magnets, ion pumps and Bayard-Alpert gauges for vacuum systems, temperature sensors for ID baking, and an interlock system (limit switches, emergency button) for safety. The design and implementation of the IU22 control system are summarized in this report.

The cryogenic permanent magnet undulator (CPMU), utilizing the magnetic characteristics of the magnets made of NdFeB or PrFeB that both the remanence and the intrinsic coercivity increase with the decrease in temperature, is a promisingly competitive insertion device type to obtain high magnetic field in short period. The Shanghai Institute of Applied Physics (SINAP) has been studying the related key technology since the early of 2013. An NdFeB-based hybrid CPMU prototype with a period of 20 mm and a magnetic length of 1.6 m was developed for the Shanghai Synchrotron Radiation Facility (SSRF). This paper presents the study on the CPMU magnet cooling technique in details. The cooling technique of the CPMU magnet array has been studied by both theoretical analyses and experimental tests. The design of the magnets cooling structure and the experimental tests are provided.

Center for Advanced Microstructures and Devices of Louisiana State University (LSU CAMD) is a research center for optimization of synchrotron radiation (SR) for production of soft X-rays. New research projects have necessitated expansion of the SR spectral range to harder X-rays. This task was solved via installation of a superconducting insertion device. This paper presents a description of the superconducting wiggler with a field of 7.5 T made by Budker INP and installed on the storage ring of LSU CAMD. The wiggler consists of 11 main bending magnets with magnetic field with alternating sign and an amplitude of 7.5 T and four side poles (two on each end of the magnet array), which are to make the first and second field integrals in the longitudinal direction equal to zero at any field level of the main poles. The main attention at the designing and production of the magnetic system of the wiggler was paid to the magnetic field quality at all field levels. Presented are results of field magnetic measurements using Hall probes. The dynamic behavior of the first and second field integrals during field ramping up and down, as measured by the method of stretched wire with current, is discussed. The wiggler was installed and successfully commissioned on the CAMD LSU storage ring in 2013.

ALBA is a Spanish synchrotron facility generating intense beams of synchrotron radiation from a 3 GeV electron accelerator. At ALBA Synchrotron, electrons are first accelerated in a 110 MeV linear accelerator and then injected in Booster ring which increases the energy up to 3 GeV. Finally, the electron beam is stored in a synchrotron Storage Ring with a current up to 400 mA emitting intense beam of synchrotron radiation. Both the Booster and the Storage Ring are located inside the same concrete building, the Tunnel, while the LINAC is located in a separated concrete building, the Bunker. Outside the Tunnel, and tangentially to the Storage Ring, are located the experimental research laboratories, the Beamlines, where scientists receive synchrotron light for a wide variety of experiments. At present ALBA has 8 Beamlines installed, 3 Beamline under construction, and 1 Beamlines in the design stage. This paper details the design of the shielding elements of the new Beamlines under construction called LOREA, NOTOS and XAIRA. The first one is a soft X-ray and the other two are hard X-ray Beamlines. Shielding calculations are performed using FLUKA Monte Carlo code and aim at quantifying the total dose rate produced by the different sources of radiation at the Beamlines in operation. In particular, it details the dose generated by the gas bremsstrahlung radiation resulting from the interaction of the 3 GeV electron beam with the residual gas of the storage ring vacuum chamber and compares it to the dose rate generated by the insertion device radiation flux. The objective of the FLUKA simulations performed in this work is to establish the requirements for all the Beamline shielding elements to ensure a public dose (dose rate lower than 0.5 μSv/h) outside the shielding during Beamline operation. Results from the simulations set the general requirements for all the Beamline shielding elements, from a radiation protection point of view.

Objective: To demonstrate the feasibility of a single electrode and grounding pad approach for delivering high frequency irreversible electroporation treatments (H-FIRE) in in-vivo hepatic tissue. Methods: Ablations were created in porcine liver under surgical anesthesia by adminstereing high frequency bursts of 0.5–5.0 μs pulses with amplitudes between 1.1–1.7 kV in the absence of cardiac synchronization or intraoperative paralytics. Finite element simulations were used to determine the electric field strength associated with the ablation margins (ELethal) and predict the ablations feasible with next generation electronics. Results: All animals survived the procedures for the protocol duration without adverse events. ELethal of 2550, 1650, and 875 V/cm were found for treatments consisting of 100x bursts containing 0.5 μs pulses and 25, 50, and 75 μs of energized-time per burst, respectively. Treatments with 1 μs pulses consisting of 100 bursts with 100 μs energized-time per burst resulted in ELethal of 650 V/cm. Conclusion: A single electrode and grounding pad approach was successfully used to create ablations in hepatic tissue. This technique has the potential to reduce challenges associated with placing multiple electrodes in anatomically challenging environments. Significance: H-FIRE is an in situ tumor ablation approach in which electrodes are placed within or around a targeted region to deliver high voltage electrical pulses. Electric fields generated around the electrodes induce irrecoverable cell membrane damage leading to predictable cell death in the relative absence of thermal damage. The sparing of architectural integrity means H-FIRE offers potential advantages compared to thermal ablation modalities for ablating tumors near critical structures.

At the Metrology Light Source, an electron storage ring dedicated to metrological applications, the U125 insertion device beamline utilizes undulator radiation for various applications over a broad spectral range. Using a hybrid normal-incidence and grazing-incidence in-vacuum switchable plane-grating monochromator, a spectral region ranging from the near-infrared to soft X-ray is covered. The beamline is dedicated to surface-analytical methods, e.g. ellipsometry, photoelectron spectroscopy or photoemission tomography. The traceability of radiometric quantities, i.e. quantitative determination of the available radiant power (or photon flux), is required for some of these applications to support the metrological aspect of the measurements. In particular, attention is paid to the suppression of unwanted spectral contributions from higher diffraction orders, and to the monitoring of the radiation intensity during the measurements. With the results from the beamline commissioning, an uncertainty budget for all relevant radiometric quantities was established.

The fresh-slice technique improved the performance of several self-amplified spontaneous emission free-electron laser schemes by granting selective control on the temporal lasing slice without spoiling the other electron bunch slices. So far, the implementation has required a special insertion device to create the beam yaw, called a dechirper. We demonstrate a novel scheme to enable fresh-slice operation based on electron energy chirp and orbit dispersion that can be implemented at any free-electron laser facility without additional hardware.

Calibration is an extremely important part of VNA measurement. It can minimize the system error of signal reflection and transmission, thus effectively improve the measurement accuracy. But when calibrating the non-insertion device, because it is not directly connected to the test port, an adapter must be used when a through connection is made. Since the adapter was used when calibrated, the measurement was not used, thus reducing the precision of the measurement, so the effect of the adapter was removed when calibrating. This causes a certain disturbance to common calibration. In this paper, we introduce some common methods of calibrating the non-insertion device and the advantages and disadvantages of these methods. And an advanced calibration method is introduced that is unknown through calibration. The principle and the algorithm are given in detail.

The Biomedical Imaging and Therapy (BMIT) beamlines at the Canadian Light Source (CLS) comprise a multi-modality synchrotron imaging facility capable of imaging objects with 2–200 μm resolution with beam sizes up to ~200 mm wide and ~10 mm high in the experimental hutches [1–3]. BMIT hosts two beamlines, a bend magnet 05B1-1 and an insertion device 05ID-2, with capabilities to apply absorption imaging, in-line phase contrast imaging (PCI), analyzer-based imaging (ABI) or diffraction-enhanced imaging (DEI), and K-Edge Subtraction (KES) imaging. Talbot or grating interferometry is under development.

A system has been developed to measure the vertical position and angle of the electron beam at a single location from a synchrotron source. The system uses a monochromator tuned to the absorption edge of a contrast material and has a sensitivity comparable with other beam position monitors., The stability of the photon beam position on synchrotron beamlines is critical for most if not all synchrotron radiation experiments. The position of the beam at the experiment or optical element location is set by the position and angle of the electron beam source as it traverses the magnetic field of the bend-magnet or insertion device. Thus an ideal photon beam monitor would be able to simultaneously measure the photon beam’s position and angle, and thus infer the electron beam’s position in phase space. X-ray diffraction is commonly used to prepare monochromatic beams on X-ray beamlines usually in the form of a double-crystal monochromator. Diffraction couples the photon wavelength or energy to the incident angle on the lattice planes within the crystal. The beam from such a monochromator will contain a spread of energies due to the vertical divergence of the photon beam from the source. This range of energies can easily cover the absorption edge of a filter element such as iodine at 33.17 keV. A vertical profile measurement of the photon beam footprint with and without the filter can be used to determine the vertical centroid position and angle of the photon beam. In the measurements described here an imaging detector is used to measure these vertical profiles with an iodine filter that horizontally covers part of the monochromatic beam. The goal was to investigate the use of a combined monochromator, filter and detector as a phase-space beam position monitor. The system was tested for sensitivity to position and angle under a number of synchrotron operating conditions, such as normal operations and special operating modes where the photon beam is intentionally altered in position and angle at the source point. The results are comparable with other methods of beam position measurement and indicate that such a system is feasible in situations where part of the synchrotron beam can be used for the phase-space measurement.

A spatially periodic magnetic field is essential to cause an electron beam to wiggle and to emit electromagnetic radiation in a synchrotron (SR) source of radiation, and to provide fully coherent light in free electron lasers (FEL). To create this field, permanent magnets (PM) or electromagnets are patterned in a device commonly called an insertion device for SR and a radiator or modulator for FEL. In reality, magnet blocks or iron poles are not identical, in terms of geometry and magnetic properties, even with progressive manufacture. Compensatory methods are thus desired to recover the magnetic field and also to decrease the duration of construction. Magnet sorting is a pre-process that aims to eliminate the effect of manufacturing error. Before assembly of an insertion device, data of each component, especially the magnetic properties of each magnet block and the gap variation of mechanical structure, are organized to optimize the performance of the magnetic field. After that process, there is sometime...

In the framework of its upgrade, the ESRF is designing a new lattice to replace the present double-bend achromat structure. This new lattice fulfills the following constraints and requirements: It fits in the present tunnel and keeps the insertion device source points at the same location;Its target horizontal emittance is around 150 pm;It keeps the electron energy at 6 GeV in order to preserve the spectral properties of the present beamlines;It minimizes the radiation losses and the magnet electrical consumption in order to decrease operating costs;The present injector complex is re-used with minor changes.

We present the application of fully- and partially-coherent synchrotron radiation wavefront propagation simulation functions, implemented in the "Synchrotron Radiation Workshop" computer code, to create a ‘virtual beamline’ mimicking the Coherent Hard X-ray scattering beamline at NSLS-II. The beamline simulation includes all optical beamline components, such as the insertion device, mirror with metrology data, slits, double crystal monochromator and refractive focusing elements (compound refractive lenses and kinoform lenses). A feature of this beamline is the exploitation of X-ray beam coherence, boosted by the low-emittance NSLS-II storage-ring, for techniques such as X-ray Photon Correlation Spectroscopy or Coherent Diffraction Imaging. The key performance parameters are the degree of Xray beam coherence and photon flux, and the trade-off between them needs to guide the beamline settings for specific experimental requirements. Simulations of key performance parameters are compared to measurements obtained during beamline commissioning, and include the spectral flux of the undulator source, the degree of transverse coherence as well as focal spot sizes.

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 1 μSv/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.

The effects of an insertion device (ID) on the beam dynamics of the PLS-II storage ring have been investigated quantitatively. Although the linear perturbations caused by high field wigglers, such as tune shift and beta-beating, are corrected by using iterative Twiss-matching, particles may be unstable in the transverse planes due to nonlinear ID fields. Intrinsic non-linear fields and transverse magnetic field roll off cause ID field-perturbations making the beam unstable and possibly causing a reduction in the injection efficiency and the beam’s lifetime. Therefore, a frequency map analysis is used to analyze the transverse dynamics with high field IDs. In order to analyze the transverse dynamics by using frequency map analysis, we model a three dimensional magnetic field based on numerical data with a Taylor expansion to accurately represent the actual field. As a result, new operation tunes, 15.245 and 9.18, are suggested rather than the designed tunes of 15.28 and 9.18. The new tunes are used for Twiss-matching and require several iterations to reduce both the horizontal and the vertical beta beatings. In this paper, the effects of an insertion device and their compensations will be presented.