Modifications of the beam profile in the new inclined crystal geometry (original) (raw)
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The CRYSTAL Storage Ring project at Legnaro
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The two stage crystal collimator for RHIC
PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268), 2001
The use of a two stage crystal collimation system in the RHIC yellow ring is examined. The system includes a copper beam scraper and a bent silicon crystal. While scrapers were installed in both of the RHIC rings before the year 2000 run, the crystal is installed for the 2001 run in one ring only, forming a two stage collimation system there. We present simulations of the expected channeling through the bent silicon crystal for both protons and gold ions with various beam parameters. This gives a picture of the particle losses around the ring, and the expected channeling efficiency. These results are then used to optimize the beam parameters in the area of the crystal to obtain maximum channeling efficiency, minimize out-scattering in the secondary collimator, and reduce beam halo.
The Materials Science Beamline at the Swiss Light Source
1999
A step-by-step account is presented describing how to determine the rotational movements of the sample and detector in order to record an ¡ hkl ¢ reflection of a single crystal mounted either in horizontal or vertical geometry on the surface diffractometer of the Materials Science beamline of the Swiss Light Source.
The materials science beamline at the Swiss Light Source: design and realization
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2005
The Materials Science Beamline at the Swiss Light Source (SLS) has been designed to produce hard X-rays in the photon-energy range 5-40 keV, at an intermediate energy (2.4 GeV) synchrotron. To this end, it employs a novel ''minigap wiggler''. Important issues in the design and realization of the beamline are the high heat load, robust system design, flexibility of operation and user-friendliness. A conventional collimating-mirror/sagittally focusing doublecrystal monochromator/focusing mirror optics has been chosen with approximately 1:1 symmetry. Established component designs have been used wherever possible. Three serial end-stations are served with X-rays. Besides the minigap wiggler, other novel or unusual features are: continuous ''top-up'' injection in the SLS storage-ring, a rotating carbon ''cup'' filter in the beamline front-end, angles and bending radii of the optics mirrors which are adjusted at each change in photon-energy and special experimental-station equipment including high-speed one-and two-dimensional semiconductor detectors for powder and surface diffraction and a two-dimensional ''Bragg magnifier'' for tomography. In this work, a comparison is made between predicted and measured beamline properties, and Appendices with useful formulae and algorithms are provided. r
A Sagittally Bent Crystal for the Short Pulse X-ray Beamline at the Advanced Photon Source
Journal of Physics: Conference Series, 2014
The Short Pulse X-ray Imaging and Microscopy (SPXIM) Beamline at the Advanced Photon Source (APS) is being designed to provide a short-pulse focused beam at the sample some 60 m from the source. The second crystal in the horizontally diffracting doublecrystal monochromator system is sagittally bent to focus the full vertical fan of the beam, preserving the flux of a typical undulator beamline at the APS, while providing a time-angle correlated beam on the sample with a few-picosecond pulse duration. An energy scan using this system requires changing the bent radius of the second crystal. Undesirable distortions in the sagittally bent second crystal are due to anticlastic deformations. In this paper, the analysis and design of the bent crystal is presented including an examination of the mechanical interaction between the crystal and the two pairs of rollers used to bend it. Ray tracings including the anticlastic deformations obtained from an optimized finite element model show a minimal effect on the spot size at the sample position.
Sadhana, 2004
An extended X-ray absorption fine structure (EXAFS) beam-line for X-ray absorption studies using energy dispersive geometry and position sensitive detector is being developed for the INDUS-II synchrotron source. The optical design of the beam-line has been completed based on the working principle that a single crystal bent in the shape of an ellipse by a crystal bender would act as a dispersing as well as focusing element. The heart of the beam-line is the crystal bender which has been designed on the basis of the principle of four-point bending and has been fabricated indigenously. The crystal bender is capable of producing pre-defined elliptical curvature on a crystal surface by applying different couples at the two-ends of the crystal which has variable width along its length. The focusing property of the crystal bender has been tested using a laser source and has been compared with the theoretically simulated results.
New results from the CERN-SPS beam deflection experiments with bent crystals
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1996
Presented at the Workshop on "Channeling and other Coherent Crystal Effects are observed. the beam splits into several beams corresponding to the different planes, and even weak planes 450 GeV/c. Qualitatively similar behaviour as in previous experiments at 12 GeV/c is seen; positive particles using axial alignment of a bent silicon crystal has been investigated at time, and a small reduction in efficiency is seen in the irradiated region. Finally, deflection of deflection efficiencies using a strongly irradiated silicon crystal have been measured for the first significantly smaller than expected for such a crystal with higher atomic number. Fourth, Slightly higher deflection efficiencies than for silicon are seen for large bending angles, but the first results from beam deflection at high energy using a germanium crystal are shown. are seen, but no negative particles are bent through the full bending angle of the crystal. Third, crystal, for incidence along the (1 1 1) plane as well as the <1l0> axis. Small deflection effects silicon crystal. Second, deflection of negative pions at 200 GeV/c is investigated for the same 450 GeV/c proton beam for a bending angle of 3.1 mrad along the (111) plane in a 50 mm presented. First, deflection of a positive pion beam at 200 GeV/c is compared to the standard Results from five distinct bending experiments performed recently in the H8 beam at CERN are