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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   

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The Canadian Light Source (CLS) is Canada's national synchrotron radiation facility. The CLS mission statement includes a mandate to “participate actively in educational, social and cultural development of our communities.” Over 6,000 people annually, more than half of them school children, tour the CLS. This is facilitated by the design of the building, which has a mezzanine affording panoramic views of the accelerators and experimental floor (see Figure 1). CLS staff have presented to more than a thousand educators through various professional development sessions, and for these educators classroom resource material is made available for easy inclusion in daily lessons where possible. The CLS also hosts an annual workshop for teachers where, since 2006, more than one hundred teachers have spent several days at CLS becoming familiar with the facility.  相似文献   

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Synchrotron-based X-ray scattering (SR-XRS) techniques offer the ability to probe nano- and atomic-scale structures that dictate the properties of advanced technological and environmental materials. Important materials studied at the Stanford Synchrotron Radiation Lightsource (SSRL) include organic and inorganic thin films and interfaces, nanoparticles, complex oxides, solutions, polymers, minerals, and poorly crystalline materials. Good planning and a good working knowledge of beamlines and techniques are required to successfully conduct SR-XRS measurements. This sixth annual School at SSRL on Synchrotron X-ray Scattering Techniques in Materials and Environmental Sciences was held at the SLAC National Accelerator Laboratory on May 29-31, 2012, and provided a practical users' guide to planning and conducting scattering measurements at SSRL beam lines. There was an emphasis on information that cannot be found in textbooks. More than 50 researchers, mostly graduate students and postdoctoral associates, participated in this workshop. Attendees represented a variety of fields including material sciences, chemical engineering, applied physics, chemistry and earth sciences.  相似文献   

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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 T. W. Wysokinski, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 775, 14 (2015).[Crossref], [Web of Science ®] [Google Scholar]3 T. W. Wysokinski, Nucl Instr Meth Phys Res A 582, 7376 (2007).[Crossref], [Web of Science ®] [Google Scholar]]. 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.  相似文献   

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Dose estimates are undertaken when injected electrons strike a tapered copper absorber of the insertion device beamline during injection at the Canadian Light Source (CLS).A model consisting of a tapered copper absorber, a wiggler vessel, a stainless steel beam pipe and a concrete ratchet and side wall is constructed. The doses immediately behind the ratchet wall are estimated by calculating the energy depositions in a water phantom that encloses the entire structure. Also estimated are the doses along the side wall and near the inner edge of the ratchet wall.The accumulated doses are calculated assuming various injection efficiencies to the storage ring and the number of electrons lost at the tapered copper absorber during injection. From these values, the dose rates are obtained with or without a local shield.  相似文献   

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Four workshops were held on November 18, 2005, prior to the plenary Users' Meeting. The sessions were well attended and featured topics of interest both to veteran synchrotron users and interested workers from a variety of disciplines, ranging from archeology and accelerator physics to plant sciences and “extreme imaging.” A one-day workshop was devoted to future single-bunch operation at the CLS. The workshop's mandate was twofold. One aim was to gauge the interest of the user community for a single bunch mode of operation, including specific requirements such as the bunch current and the bunch purity.  相似文献   

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X-ray PEEM at liquid helium temperatures at a 3rd generation synchrotron is discussed. Detailed instrument design and performance is presented along with examples of the scientific opportunities afforded through routine low temperature performance with negligible tradeoffs of imaging performance or general ease of use.  相似文献   

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

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Synchrotron-based engineering science covers a large field of applications. However, they are all connected in two ways. First, the very synchrotron techniques employed to study the various applications all work in the same way in that they determine structural parameters on the atomic and microscopic scale. Secondly, the portfolio of applications discussed here describes the complete life cycle of an engineering material, starting with processing of the base material—often from the melt—then the characterization of material properties, followed by the forming and joining into components, then component characterization during service, material aging, damage and failure and, finally, recycling or decommissioning. The structural problems which occur during the different stages in the life cycle of a material are complex, due to the advanced material technology of today's devices. We have created alloys for special applications, compound materials with novel properties, sophisticated bulk and surface treatments, and new forming and joining techniques. We are also concerned with the effect of the material on the environment after it has ended its service.  相似文献   

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The Advanced Light Source (ALS) is a 1.9-GeV, third-generation synchrotron optimized for the production of VUV and soft X-rays from undulators. There is also a hard X-ray program at the ALS, which is based around three 6-T superconducting bending magnets [1 Robin, D. Proceedings of the 2002 European Particle Accelerator Conference. Paris, France. pp.215Geneva: EPAC..  [Google Scholar]] that shift the critical energy from 3 keV to 12 keV. The extreme conditions beamline at the ALS is situated on Beamline 12.2.2, which benefits from radiation produced by one of these superbend sources. The beamline is designed for X-ray diffraction, X-ray spectroscopy, and X-ray imaging of samples held in diamond-anvil high-pressure cells (DACs). In a DAC, samples are on the order of 10 to 50 μm in diameter and 10 to 30 μm thick and are contained in a metal gasket of typical inner diameters of 100 to 150 μm. For high-quality diffraction patterns with little or no contamination from diffraction from the gasket, the X-ray beam size needs to be on the order of 10 μm × 10 μm.  相似文献   

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A radiation shielding study against primary and secondary gas bremsstrahlung is carried out for a tungsten collimator/stop, which is one of the components employed in the VESPERS beamline at the Canadian Light Source. The dose and dose rate are obtained by calculating the energy deposition in a water phantom which surrounds the collimator/stop unit. The dose rate behind a vacuum hole of the collimator/stop which leads to the experimental hutch is closely examined. The dose rates are further investigated with the addition of a tungsten shutter that is positioned in front of the collimator/stop.  相似文献   

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No energy, whether renewable, clean or known by any other name can possibly be relied upon as the only solution for ensuring a supply of electricity compatible with a nation’s economic and social development. Brazilian consumption and installed capacity of electric power generation per capita indices are still inadequate and below the world average—this crucial fact must be considered. It obliges Brazil to take the most advantage of all resources available to increase its electricity generation capacity as rapidly as possible, thereby enabling consumption to reach levels compatible with the quality of life the Brazilian population aspires to. Planning of a country’s electric system requires efficient management of a diversified portfolio of energy sources. In Brazil, hydroelectricity will continue for many years yet to be the main component of its portfolio of electric power generation sources, but it must be supplemented by thermal sources—uranium, coal, biomass, natural gas, and oil by-products derived from petroleum—in this order of importance, keeping in mind aspects related to local availability, cost, environmental impacts, and use in other applications.  相似文献   

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I discuss some of the most outstanding challenges in relativistic astrophysics in the subjects of compact objects (black holes and neutron stars), dark sector (dark matter and dark energy), plasma astrophysics (origin of jets, cosmic rays, and magnetic fields), and the primordial universe (physics at the beginning of the Universe). In these four subjects, I discuss 12 of the most important challenges. These challenges give us insight into new physics that can only be studied in the large scale universe. The near-future possibilities, in observations and theory, for addressing these challenges are also discussed.  相似文献   

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Synchrotron radiation circular dichroism (SRCD) is a well established technique in structural biology. The first UV‐VIS beamline, dedicated to circular dichroism, at Diamond Light Source Ltd, a third‐generation synchrotron facility in south Oxfordshire, UK, has recently become operational and it is now available for the user community. Herein the main characteristics of the B23 SRCD beamline, the ancillary facilities available for users, and some of the recent advances achieved are summarized.  相似文献   

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