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1.
This workshop was held to gather scientists interested in exploiting beamlines I06 and I10 of the Surface and Interfaces Village at Diamond Light Source from June 10–11, 2009. Sarnjeet Dhesi introduced the meeting with a short explanation of the village structure at Diamond. This village includes the Nanoscience beamline (I06), catering for soft X-rays for Photo-Emission Electron Microscopy (PEEM) and X-ray Magnetic Circular and Linear Dichroism (XMCD and XMLD), and the Beam Line for Advanced Dichroism Experiments (BLADE, beamline I10), which is a polarized soft X-ray beam for XMCD, XMLD, and soft X-ray diffraction. I06 has been operational for over two years, while I10 is scheduled to come on-line in late 2010. In addition, there are two surface science beamlines (I07 and I09) in the village dedicated to surface diffraction and X-ray standing waves.  相似文献   

2.
ALBA is the Spanish synchrotron facility located in the area of Barcelona. It is a low-emittance, 3 GeV machine having, at present, seven state-of-the-art operating beamlines covering soft and hard X-rays. The hard X-ray beamlines comprise macromolecular crystallography, non-crystalline diffraction (SAXS and WAXS), high-resolution powder diffraction, and absorption spectroscopy. The soft X-ray beamlines include a photoemission beamline with two endstations—one devoted to photoelectron microscopy (PEEM) and the second to near ambient pressure photoemission (NAPP)—and another beamline devoted to XMCD and soft X-ray scattering. Both beamlines allow full control of the polarization of the beam, since they are equipped with helical undulators. An additional soft X-ray beamline, installed on a bending magnet port, is equipped with a full-field transmission X-ray microscope. Additional information may be found at http://www.albasynchrotron.es/en/beamlines.  相似文献   

3.
Synchrotron infrared beamlines are powerful tools on which to perform spectroscopy on microscopic length scales but require working with large bending‐magnet source apertures in order to provide intense photon beams to the experiments. Many infrared beamlines use a single toroidal‐shaped mirror to focus the source emission which generates, for large apertures, beams with significant geometrical aberrations resulting from the shape of the source and the beamline optics. In this paper, an optical layout optimized for synchrotron infrared beamlines, that removes almost totally the geometrical aberrations of the source, is presented and analyzed. This layout is already operational on the IR beamline of the Brazilian synchrotron. An infrared beamline design based on a SOLEIL bending‐magnet source is given as an example, which could be useful for future IR beamline improvements at this facility.  相似文献   

4.
Vibration is often a problem causing poor quality of photon beams at synchrotron radiation facilities, since beamlines are quite sensitive to vibrations. Therefore, vibration analysis and control at synchrotron radiation facilities is crucial. This paper presents investigations on mechanical vibrations at four beamlines and endstations at the Canadian Light Source, i.e. the Canadian Macromolecular Crystallography Facility 08ID‐1 beamline, the Hard X‐ray MicroAnalysis 06ID‐1 beamline, the Resonant Elastic and Inelastic Soft X‐ray Scattering 10ID‐2 beamline, and the Scanning Transmission X‐ray Microscope endstation at the Spectromicroscopy 10ID‐1 beamline. This study identifies vibration sources and investigates the influence of mechanical vibrations on beamline performance. The results show that vibrations caused by movable mechanical equipment significantly affect the data acquired from beamlines.  相似文献   

5.
The aim of the present work is to make a comparative study of the EXAFS spectra recorded at the BL-8 dispersive EXAFS beamline at 2 GeV Indus-2 synchrotron source at RRCAT, Indore (India) with those recorded at other synchrotron EXAFS beamlines, viz., X-19A at NSLS, BNL (USA), EXAFS wiggler beamline 4-1 at the SSRL (USA) and beamline 11.1 at ELETTRA (Italy). For this purpose, EXAFS spectra at Cu K-edge in copper metal have been recorded at these four beamlines. Further, EXAFS spectra at Cu K-edge in a copper complex have also been recorded at BL-8 beamline and beamline 11.1 at ELETTRA (Italy). The obtained experimental μ(E) data have been background-subtracted and then normalized. The normalized data have been then converted to χ(k) data, which have been Fourier-transformed and then fitted with the theoretical model, thereby yielding different structural parameters. It has been shown that the results obtained from the EXAFS spectra recorded at the BL-8 beamline are comparable with those obtained from other synchrotron EXAFS beamlines and also with the crystallographic results reported by earlier workers. The reliability, usefulness and data quality of the BL-8 beamline have been discussed.  相似文献   

6.
The EMBL Hamburg Outstation currently operates two tunable protein crystallography beamlines suitable for single and multiple anomalous diffraction (SAD/MAD) experiments. The first beamline, designated X31, is located on a bending magnet of the DORIS III storage ring whereas the second beamline, BW7A, is positioned at a multipole wiggler at the same storage ring. X31 is equipped with an energy stabilization device to ensure constant wavelength during longer data-collection periods. The in-house built crystallographic end-station is now equipped with a Mar345 imaging-plate scanner as a detector. The wiggler beamline BW7A features a novel sagitally focusing monochromator. The end-station used here has also been developed and built in-house. The beamline is currently operated with a Mar 165 CCD detector. In this paper the hardware and software developments of the last years will be summarized and the outlook for substantial upgrades will be given. The future plans include the design and construction of a third tunable beamline, designated X12, for protein crystallography. The development of automated beamlines for protein crystallography is of particular importance with respect to structural genomics initiatives. The analysis of the projects of the last years shows the wide range of anomalous scatterer used on the tunable beamlines thus demonstrating the need of a wide range of accessible energies and fast and reliable energy changes.  相似文献   

7.
Biological small-angle X-ray scattering (SAXS) provides powerful complementary data for macromolecular crystallography (MX) by defining shape, conformation and assembly in solution. Although SAXS is in principle the highest throughput technique for structural biology, data collection is limited in practice by current data collection software. Here the adaption of beamline control software, historically developed for MX beamlines, for the efficient operation and high-throughput data collection at synchrotron SAXS beamlines is reported. The Blu-Ice GUI and Distributed Control System (DCS) developed in the Macromolecular Crystallography Group at the Stanford Synchrotron Radiation Laboratory has been optimized, extended and enhanced to suit the specific needs of the biological SAXS endstation at the SIBYLS beamline at the Advanced Light Source. The customizations reported here provide a potential route for other SAXS beamlines in need of robust and efficient beamline control software. As a great deal of effort and optimization has gone into crystallographic software, the adaption and extension of crystallographic software may prove to be a general strategy to provide advanced SAXS software for the synchrotron community. In this way effort can be put into optimizing features for SAXS rather than reproducing those that have already been successfully implemented for the crystallographic community.  相似文献   

8.
The short wavelength of X-rays makes them an excellent choice for probing materials on the nanometer scale and for crystallography of sub-micrometer crystallites. The objective of nanofocusing optics is to produce a small, focused beam size in order to obtain the highest X-ray flux on a small sample or as a fine spatial probe. Achieving nanometer-scale focused X-ray beam sizes puts great demands on the optical elements in an X-ray beamline—the optics must balance the requirements to de-magnify the electron beam X-ray source, to reduce the diffraction-limited focus size, and to minimize the contribution to the focus of aberrations in the optics while collecting the maximum X-ray flux into the focused beam. These requirements dictate that an extreme demagnifying geometry should be employed and that high-specification optical elements must be used. Nanofocusing optics has often been added as an upgrade to existing beamlines at Diamond, extending the range of science that can be carried out. Extreme nanofocusing also forms the basis of new beamlines at Diamond, such as the nanoprobe beamline (I14), which aims to provide sub-30-nm-dimension focused X-ray beams for mapping samples at high spatial resolution. The demand for nanometer-scale diffraction-limited X-ray beams is expected to grow at Diamond and requires corresponding advances in X-ray optics to exploit the present source and future lower emittance storage ring sources; for example, the proposed Diamond II upgrade, projected to give a factor 20 emittance reduction.  相似文献   

9.
In early July 2011 it became clear that the initial MAX IV beamline program would receive the required funding of 400 MSEK from the Knut and Alice Wallenberg Foundation and 160 MSEK from Swedish universities. The construction program will start immediately and the beamlines are projected to be operative in late 2015.  相似文献   

10.
The International Synchrotron Radiation Circular Dichroism (SRCD) Spectroscopy Meeting was held at the Physikzentrum, Bad Honnef, Germany on May 17–20, 2015, as the 590th WE-Heraeus-Seminar. It was the third in the series of SRCD Workshops, following the first one held at the Daresbury Synchrotron (UK) in 2001, and the second at the Beijing Synchrotron Radiation Facility (BSRF) and the Institute of High Energy Physics (IHEP) in 2009. SRCD2015 was organized by Dr. Jochen Bürck, Prof. Anne Ulrich, and Dr. Dirk Windisch (all of Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, Germany) and Prof. Bonnie Ann Wallace (Birkbeck College, University of London, UK). It was aimed at both synchrotron CD beamline scientists and scientific users of the beamlines, and included participants from 14 countries. For the first time, representatives of all operational SRCD beamlines worldwide were present at the same meeting, and scientists developing two new SRCD beamlines also participated.  相似文献   

11.
There are currently no simple and easy to apply techniques for determining the degree of linear polarization of a soft X-ray beam delivered by a synchrotron beamline despite the fact that this parameter is important for a wide range of synchrotron-based soft X-ray experiments. This work presents a new method for the quantitative determination of the linear polarization state of synchrotron radiation using an HOPG crystal as the standard sample. The method is straightforward to perform without the need for experimental apparatus beyond that commonly available at beamlines in this energy range. In addition, the high-degree of order that can easily be achieved in a HOPG sample means that it is potentially more accurate than currently employed comparative methods. We show how the method can be applied to experimentally determine the linear polarization state of various soft X-ray synchrotron beamlines and we discuss the wide variations in the degree of linear polarization that are measured.  相似文献   

12.
Carbon NEXAFS and EELS spectra of soot, and NEXAFS spectra of soot extracts, are presented. The EELS spectra of solid soot particles from a TEM-EELS show fewer structures than the corresponding NEXAFS spectra obtained at two different synchrotron beamlines. We attribute radiation damage in the TEM-EELS to the failure at resolving structures of surface functional carbon groups in or on soot. NEXAFS spectra of soot extracts studied with a scanning transmission X-ray microscope show alterations during X-ray exposure, which can be explained by a simple chemical model where oxygen apparently reacts with the sample. When the same extract is studied in an ultrahigh-vacuum beamline, no such alterations are observed.  相似文献   

13.
Abstract

In the second phase construction of further insertion devices, beamlines and experimental stations at the Beijing Synchrotron Radiation Facility, a dedicated high-pressure x-ray diffraction station will be constructed. We outline the synchrotron radiation source, beamline optics and high-pressure x-ray diffraction apparatus. This facility is planned to operate for users in 1994.

Presented at the IUCr Workshop on ‘Synchrotron Radiation Instrumentation for High Pressure Crystallography’, Daresbury Laboratory 20-21 July 1991  相似文献   

14.
在北京同步辐射装置新建4B7B束线没有安装反射率计,且用户空间有限的情况下,利用X光基准点还原的方法建立了一种Dante谱仪固定角度平面镜反射率标定方法。利用三光束瞄准方法完成了束线软X光基准重建,通过准直方法实现了平面镜与X光之间的高定角精度,并采取了相应的角度姿态监测,最终在实验中得到的平面镜标定角不确定度为1.0 mrad。基于固定角度平面镜多次安装和朝各个方向转动后的标定结果,获得了高精度的反射率曲线。  相似文献   

15.
Three-dimensional structures derived from X-ray diffraction of protein crystals provide a wealth of information. Features and interactions important for the function of macromolecules can be deduced and catalytic mechanisms postulated. Still, many questions can remain, for example regarding metal oxidation states and the interpretation of `mystery density', i.e. ambiguous or unknown features within the electron density maps, especially at ~2 ? resolutions typical of most macromolecular structures. Beamline X26-C at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory (BNL), provides researchers with the opportunity to not only determine the atomic structure of their samples but also to explore the electronic and vibrational characteristics of the sample before, during and after X-ray diffraction data collection. When samples are maintained under cryo-conditions, an opportunity to promote and follow photochemical reactions in situ as a function of X-ray exposure is also provided. Plans are in place to further expand the capabilities at beamline X26-C and to develop beamlines at NSLS-II, currently under construction at BNL, which will provide users access to a wide array of complementary spectroscopic methods in addition to high-quality X-ray diffraction data.  相似文献   

16.
Based on the radiation characteristics of the bend magnet source, the output characteristics of the BSRF-3B3 beamline was analyzed and discussed. The result is the foundation of adjustment and diagnosis of the beamline. A calculation model is provided to analyze characteristics of beamlines attached to bend magnet sources.  相似文献   

17.
从北京正负电子对撞机储存环弯转磁铁光源的辐射特性入手, 分析了BSRF-3B3光源及其光束线光学系统的输出特性, 分别给出各光学元件的传输效率和采用不同单色器晶体在样品处的计算结果. 为光束线设计、调试及诊断提供了理论依据. 同时也为弯转磁铁光源光束线的输出特性的计算, 提供了一个模式.  相似文献   

18.
The diffraction beamline BM01A at the European Synchrotron Radiation Facility (CRG Swiss–Norwegian beamlines) has been successfully operational for 20 years. Recently, a new multifunctional diffractometer based on the Dectris Pilatus 2M detector has been constructed, commissioned and offered to users. The diffractometer combines a fast and low‐noise area detector, which can be tilted and moved horizontally and vertically, together with flexible goniometry for sample positioning and orientation. The diffractometer is controlled by a user‐friendly and GUI‐based software Pylatus which is also used to control various auxiliary equipment. The latter includes several heating and cooling devices, in situ cells and complimentary spectroscopic tools.  相似文献   

19.
To foster scientific collaborations among the Advanced Photon Source (APS), the European Synchrotron Radiation Facility (ESRF), and the Super Photon Ring-8 GeV (SPring-8), the three facilities meet on a regular basis to hold technical discussions on accelerator and beamline topics and management and operational issues of common interest. The 2008 Three-Way Meeting (3WM) was held on March 18–19 at the APS with more than 20 representatives from each facility. Satellite workshops were also held on the topics of X-ray Optics, Nanoscience with X-rays, User Services, and Accelerator R&;D. The 3WM and satellite workshops served as platforms for presentations and discussions of new and exciting developments at the three synchrotron sources.  相似文献   

20.
The NSLS-II storage ring completed commissioning in 2014 and all project-beamline IDs have also been commissioned. As of February 2015, six beamlines are about to finish commissioning. By the end of 2015, the ring is expected to store 300 mA with top-up injection capability and 500 mA with a second superconducting RF cavity installed in the following year. The design principle of the NSLS-II ring is to employ low-field BMs and simultaneously install high-field wigglers in non-dispersive straights to reduce the horizontal emittance. The more wigglers are installed, the smaller the horizontal electron beam emittance becomes. At this stage, six 3.4-m-long wigglers with 1.8 T effective field and 100 mm period length have been installed in three straight sections, which could reduce emittance in a bare lattice from 2.1 nm.rad to approximately 1.0 nm. rad. Two 2.0-m-long EPU49s are installed for the coherent soft X-ray (CSX) beamline in a short straight (SS) section also known as the low-βx straight section. These are Apple-II-type devices with four movable arrays. Two 3.0-m-long IVU20s are installed in two SS's, one for the Hard X-ray Nano-Probe (HXN) beamline and the other for the Coherent Hard X-ray (CHX) beamline. One 1.5-m-long IVU21 is installed in a canted short straight section for the Sub-Micron Resolution X-ray Spectroscopy (SRX) beamline. Its canting angle is 2 mrad outboard in the center of the straight section. The first ID for this beamline is installed in the downstream portion of the straight section. Another 3.0-m-long IVU22 is installed in a long straight section (LS: high-βx) where a second device is planned to be added in the future. Three 2.8-m-long IVU23s are planned to be installed in long straight sections, either in an asymmetric canted configuration or in a straight configuration. One 1.4 m EPU57 and one 2.8 m EPU105 are planned for the Electron Spectro-Microscopy (ESM) beamline in a SS, while one 3.5m EPU57 in a LS is planned for the Soft Inelastic X-ray Scattering (SIX) beamline. Table 1 shows the specifications of all the IDs funded so far.  相似文献   

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