The design principles, construction and characterization of a 4- bounce dispersive crystal monochromator is discussed. This monochromator is designed to reduce the bandpass of synchrotron radiation to 10--50 meV level, without sacrificing angular acceptance. This is achieved by combining an asymmetrically-cut, low ...
DOE Information Bridge
The vertical divergences of bending magnet and wiggler synchrotron sources are generally considerably larger than the acceptance angles of typical monochromator systems. This is particularly true at high energies (E greater than or equal to 14 keV) where the Darwin widths of perfect crystals are of the order 10/sup -6/ radians. By ...
The possibility to use X-ray multilayer mirrors (XMLMs) as synchrotron radiation (SR) X-ray monochromators was investigated. It was shown that XMLMs have advantages in comparison with ideal crystal monochromators when used in experiments demanding the waveband (??/?) 10-1-10-3 and acceptance angles from 0.02 to 5 ...
NASA Astrophysics Data System (ADS)
A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut ...
DOEpatents
Simple methods for the cooling of the second crystals of cryogenically cooled undulator and wiggler double crystal monochromators are described. Copper braids between the first and second crystals are used to cool the second crystals of the double crystal ...
For the beamlines of the new synchrotron radiation source PETRA III, fixed exit double crystal monochromators with specific features were developed. To achieve a compact arrangement of the canted undulator beamlines at Sectors 2 and 6, it is necessary to shift one of the two beamlines in vertical direction. This is done by Large Offset ...
At the Advanced Photon Source (APS), undulator insertion devices are capable of producing x-ray beams with total power of about 5 kW and normal incidence heat fluxes of about 170 W/mm{sup 2} at 30 m from the source. On beamlines in which the first optical element is a mirror, the reflected beam from the mirror still carries considerable power and power density. Depending on its location, the ...
Energy Citations Database
We describe the sagittal focusing of x rays with singly bent crystals that accept the meridian plane divergence from a similar but flat crystal to form a pair in a nondispersive two-crystal Bragg monochromator. Curved crystals can intercept from 5 to 20 times the sagittal ...
... Title : X-RAY ANALYSIS APPARATUS INCLUDING A MONOCHROMATOR CRYSTAL HAVING CRYSTAL LATTICE SURFACES - PATENT ...
DTIC Science & Technology
A variable incident angle, asymmetric cut, double crystal monochromator was tested for use on beamlines at the Advanced Photon Source (APS). For both undulator and wiggler beams the monochromator can expand area of footprint of beam on surface of the crystals to 50 times the area of incident beam; this will reduce ...
Cryogenically cooled, single-crystal silicon, x-ray monochromators offer much better thermal performance than room-temperature silicon monochromators. The improved performance can be quantified by a figure-of-merit equal to the ratio of the thermal conductivity to the coefficient of thermal expansion. This ratio increases by about a ...
Curved crystal, focusing monochromators featuring cubed-root thickness profiles typically employ side-clamped cooling to reduce thermally induced overall bend deformation of the crystal. While performance is improved, residual bend deformation is often an...
National Technical Information Service (NTIS)
A continuous bent sagittally focusing monochromator has been designed and built. The monochromator is compatible with the present single-point bender apparatus designed for polygonal (ribbed) triangular sagittally focusing monochromators. This monochromator implements a new design concept taking advantage of a ...
A new simple design for a fixed-exit monochromator has been developed. The set-up uses a linear slide to couple the rotation of the crystals to a translation of the second one to compensate for the 2hcos{theta} dependence of the beam-offset in a double crystal monochromator. This set-up requires just one motor for ...
The APS sector 33 bending magnet beamline was designed to provide high X-ray flux with relatively small focal spot (1 mm�0.5 mm with �1012 ph/s/100 mA flux) and energy resolution limited mostly by the intrinsic resolution of the monochromator optics, ?E/E=1.5�10-4. The beamline accepts 4 mrad of the dipole radiation fan and uses a fixed offset ...
A beamline for macromolecular crystallography has been designed for the ALS. The source will be a 37-pole wiggler with a, 2-T on-axis peak field. The wiggler will illuminate three beamlines, each accepting 3 mrad of horizontal aperture. The central beamline will primarily be used for multiple-wavelength anomalous dispersion measurements in the wavelength range from 4 to 0.9 ...
The combined effect of focussing and diffraction for a double crystal monochromator which is being designed for the Superconducting Wiggler beamline (SCOW) on ADONE. A double separated crystal system has been chosen; the possibility of obtaining focalizat...
The sensitivity of a novel inclined crystal monochromator design to misalignments has been calculated, and compared to data. Rocking curve line narrowing as well as broadening can occur because the asymmetry factor of dynamical diffraction given by b=s(su...
The relative merits of crystals versus mirrors for focusing synchrotron radiation at energies above 10 keV are explored. As mirrors have critical angles of reflection typically 1/20 of the Bragg scattering angles for crystals, large mirror surface areas are required. Sagittal focusing is weak for mirrors and limits the amount of radiation intercepted. ...
The Oak Ridge National Laboratory's (ORNL) beamline at the National Synchrotron Light Source (NSLS) incorporates several novel features including x-ray optics based on sagittal focusing with crystals and a cantilevered mirror whose center becomes the pivot for all downstream optical elements. Crystal focusing accepts a much ...
Silicon crystal mirrors are used to reflect high-intensity X-ray beams. A large amount of heat is generated in each mirror. To minimize the effect of thermal expansion on the crystal mirrors, heat is removed by pumping liquid gallium (with a boiling point of 29.8 C) through passages in the crystal mirrors. During system operation, ...
The major problem in neutron protein crystallography is the low flux of present neutron sources. The collection of a data set using a conventional rotation technique and a 2D detector takes many weeks. One way to increase the flux at the sample is to increase the wavelength bandwidth. The conventional technique using a standard monochromator like Cu or Be has a typical ...
The authors have designed a double crystal, fixed exit monochromator which allows windowless operation of the APS beamlines. The crystals are mounted on a turntable with the first crystal at the center of rotation. A mechanical linkage is used to correctly position the second crystal and ...
The design of high-precision tunable double crystal monochromator is described. Each crystal of the monochromator can be aligned independently by a double-axis gimbal mechanism providing rotations about two perpendicular axes. Two orthogonal linear actuators operate the gimbal mechanism via a connecting bar. The ...
The performance of a dynamical sagittal-focusing monochromator for hard X-rays is described. It consists of a flat first crystal and a diamond-shaped ribbed second crystal which is clamped by its central rib and dynamically bent by applying a force on its two apices. The system has proved to perform very well on the GILDA beamline at ...
PubMed
The soft x-ray micro-characterization beamline (SXRMB) has recently undergone commissioning at the Canadian Light Source. SXRMB is a synchrotron bending magnet based design that covers a photon energy range of 1.7-10 keV, using a double-crystal monochromator that employs two crystal pairs - InSb-111 and Si-111. The indium antimonide ...
... Abstract : The first crystal of the Brown-Hower x ray monochromator of the LBL-EXXON 54 pole wiggler beamline at Stanford Synchrotron Radiation ...
General properties of monochromators are discussed, and some useful formulas for optical design are given. The discussion is limited to the Rowland reflection grating. Topics covered include focussing properties of a toroidal grating, aberrations, dispersion, resolution, and phase space acceptance. (LEW)
It is shown that for reflection-type quartz bent--crystal monochromators, the penetration aberration is the limiting factor on the monochromator resolution in the case of isolation of the K alpha /sub 1/ component of K alpha x rays, especially for shorter wavelengths. The residual K alpha /sub 2/ relative intensity due to ...
This paper describes a UHV-compatible double crystal monochromator with independent drives for 2 linear and 2 angular crystal motions. Precise angular crystal positioning is achieved by using a spindle with a double gimbal mechanism, which converts linear motion of 0.1 micron to an angular motion of 0.042 arcsec. ...
Single crystal silicon has been the material of choice for x-ray monochromators for the past several decades. However, the need for suitable monochromators to handle the high heat load of the next generation synchrotron x-ray beams on the one hand and the rapid and on-going advances in synthetic diamond technology on the other make a ...
The analytical results and design considerations for a novel cryogenically cooled Advanced Photon Source (APS) monochromator are presented. Because the monochromator uses silicon crystal, cryogenic cooling enables one to take advantage of the high conductivity and low thermal expansion coefficient of silicon at cryogenic temperatures. ...
Various focusing monochromators are compared and evaluated for use in an EXAFS spectrometer. For a line focus the Johann and Johansson case are found to be most suitable. Obtaining a point focus is more difficult, with the best case appearing to be a singly bent mirror used in conjunction with the Johann or Johansson crystals.
There has been considerable interest in the use of diamonds in high heat load monochromators (HHLMs) in the last several years. The superb thermal and mechanical properties of single crystal diamonds serve to minimize distortions caused by a given thermal...
The resolution and efficiency of the rotating crystal chopper are derived theoretically as a function of the crystal and collimator parameters. It is shown that the limiting resolution of the device is the same as that of a crystal monochromator. An experimental model chopper is described and its observed ...
In the design of Sector II of the Synchrotron Radiation Instrumentation (SRI) CAT, an x-ray mirror with multiple coatings is chosen as the first optical component of the undulator beamline. Two significant advantages of using the mirror are: A significant reduction in the peak radiation heat flux and total power on the downstream monochromator, and (2) availability of the ...
The triple monochromator for the TOF neutron spectrometer Pelican at ANSTO has been fully optimised in terms of overall performance, including the determination of the thickness of the pyrolytic graphite crystals. A total of 24 composite crystals were designed and fabricated. The calculated optimum thickness of 1.3 mm and the length of ...
A double crystal monochromator including two identical, parallel crystals, each of which is cut such that the normal to the diffraction planes of interest makes an angle less than 90 degrees with the surface normal. Diffraction is symmetric, regardless of whether the crystals are symmetrically or asymmetrically ...
A double crystal monochromator is described including two identical, parallel crystals, each of which is cut such that the normal to the diffraction planes of interest makes an angle less than 90 degrees with the surface normal. Diffraction is symmetric, regardless of whether the crystals are symmetrically or ...
This paper describes the design, expected performance, and preliminary test results of a contact-cooled monochromator for use on high heat load x-ray beamlines. The monochromator has a cross section in the shape of the letter U. This monochromator should be suitable for handing heat fluxes up to 5 W/square millimeter. As such, for the ...
We have tested the first diamond double-crystal monochromator at the Advanced Photon Source (APS). The monochromator consisted of two synthetic type lb (111) diamond plates in symmetric Bragg geometry. We tested two pairs of single-crystal plates: the first pair was 6 mm by 5 mm by 0.25 mm and 6 mm by 5 mm by 0.37 ...
A monochromator system consisting of perfect silicon crystal lamellae is described. The resolution and the intensity of this lamellae-system can be controlled by choice. It can be used in plane or bent configuration. In case of bent lamellae, some criteria are given for the validity of the dynamical theory of diffraction by bent lattices. In a ...
A monochromator for use at 13.84 keV with a calculated bandpass of 5.2 meV was designed built, and tested. Tuning was performed by rotating the inner crystal of a pair of nested silicon channel-cut crystals. The inner crystal employs the (884) reflection, and the outer crystal employs a ...
For several neutron tomography methods, the use of monochromatic radiation is important. In order to select a wavelength band from a white spectrum commonly used devices are velocity selectors, choppers and crystal monochromators. We show how a crystal monochromator changes the well-known L/D-ratio in CT ...
... spectral response of silicon photovoltaic cells over a ... The cells, a diffused- junction, single-crystal ... a prism-monochromator illuminated the silicon cell. ...
A computer program TISTA has been employed to study the behavior of reactor-neutrons at the sample position of a neutron spectrometer diffracted from Ge(111), (220), and (311) monochromators. Our aim is to design a double axis neutron spectrometer and to determine the behavior of beam intensity and resolution at the sample position. The study will be helpful to design ...
A set of Fortran programs have been developed to calculate the expected throughput of x-ray monochromators with a filtered synchrotron source and is applicable to bending magnet and wiggler beamlines. These programs calculate the normalized throughput and filtered synchrotron spectrum passed by multiple element, flat un- focussed monochromator ...
A double crystal monochromator at the Stanford Synchrotron Radiation Laboratory is used to study the
NASA Technical Reports Server (NTRS)
An ultra-high vacuum double-crystal fixed-exit x-ray monochromator has been designed and built for soft X-ray (0.8-8 KeV) spectroscopic studies. This unit, currently installed at the NSLS on beamline X-11B, uses two crystal carousels, each of which can ho...
Point-focusing Johansson Ge monochromator crystal designed for Cu K? radiation and 333 diffraction condition with a radius of curvature of 300 mm is presented. The crystal was prepared by a hot plastic deformation at a temperature very close to the melting point of Ge. Good crystal quality and precise deformation ...
In this paper we present an exploratory study of the thermal performance of silicon and diamond monochromators of both natural and pure isotopic composition under the heat load generated by X-ray Free Electron Lasers (X-FELs). The thermo-mechanical performance of these crystals are compared and discussed. The impact of the particular time structure of the ...
A novel, silicon crystal monochromator has been designed and tested for use on undulator and focused wiggler beamlines at third-generation synchrotron sources. The crystal utilizes a thin, partially transmitting diffracting element fabricated within a liq...
This document contains the design specifications of the APS high heat load (HHL) monochromator and associated accessories as of February 1993. It should be noted that work is continuing on many parts of the monochromator including the mechanical design, crystal cooling designs, etc. Where appropriate, we have tried to add supporting ...
Sagittal focusing of undulator radiation is shown to be compatible with the proposed inclined double-crystal monochromator geometry for heat load reduction. The focusing aberrations are found to be negligible for typical undulator-beam divergences over a ...
This paper describes the experimental and analytical program in cryogenic cooling of high-heat-load optics at the Advanced-Photon Source. A prototype liquid nitrogen pumping system has been procured. This pump provides a variable flow rate of 1 to 10 gpm of pressurized liquid nitrogen and is sized to handle up to 5 kW of optic heat load. Also, a high-vacuum, double-crystal ...
Silicon saw-tooth refractive lenses have been in successful use for vertical focusing and collimation of high-energy X-rays (50-100 keV) at the 1-ID undulator beamline of the Advanced Photon Source. In addition to presenting an effectively parabolic thickness profile, as required for aberration-free refractive optics, these devices allow high transmission and continuous tunability in photon energy ...
A common view is that color displays cannot match the performance of monochrome displays, normally used for diagnostic x-ray imaging. This view is based largely on historical experience with cathode-ray tube (CRT) displays, and does not apply in the same way to liquid-crystal displays (LCDs). Recent advances in color LCD technology have considerably ...
A monochromator stabilization system with a semi-automatic tuning procedure has been developed. The system comprises an X-ray beam position/intensity monitor, a control electronics unit, a computer program that operates on a personal computer or workstation, a piezo translator attached to the first crystal of a double crystal ...
In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto ...
Curved crystal, focusing monochromators featuring cubed-root thickness profiles typically employ side-clamped cooling to reduce thermally induced overall bend deformation of the crystal. While performance is improved, residual bend deformation is often an important limiting factor in the monochromator performance. ...
At the high energy synchrotron radiation beamline BW5 at DORIS III at DESY a new monochromator providing broad energy bandwidth and high reflectivity is in use. On a small 10�10�5 mm3 silicon crystal scattering at the (311) reflection a thermal gradient is applied, which tunes the scattered energy bandwidth. The (311) reflection strongly suppresses the ...
The use of cryogenically cooled monochromators looks to be a very Promising possibility for the Advanced Photon Source. This position has recently been bolstered by several experiments performed on beamlines at the ESRF and CHESS. At the ESRF, several crystal geometries have been tested that were designed for high power densities (> 150 W/mm{sup 2})and ...
A new revolving monochromator intercepting 2 mrad of the radiation fan at the State University of New York (SUNY) X3 beamline at the National Synchrotron Light Source (NSLS) is described. The design allows for easy interchange between four different monochromator crystals. The photons are reflected in the horizontal plane to provide a ...
Two sequential simulation studies were conducted to evaluate the usability and acceptability of pictorial format displays for fighter aircraft; to determine whether usability and acceptability were affected by display mode--color or monochrome; and to rec...
The performance and application of an ultra-high-vacuum compatible constant-deviation double-crystal monochromator (JUMBO) in operation at SSRL is demonstrated. The monochromator can be operated with any of four pairs of crystals interchangeable in situ. An electronic-maximum-search feedback loop optimizes the ...
The design and performance of a new double crystal monochromator for x-ray undulator beamline at the PF-AR are described. The monochromator consists of flat silicon (111) crystals, which are cooled by liquid nitrogen in order to reduce the deformation caused by a heat load problem. One of the characteristic points ...
A study of the coherence and wavefront properties of a pseudo-channel-cut monochromator in comparison with a double-crystal monochromator is presented. Using a double-grating interferometer designed for the hard X-ray regime, the complex coherence factor was measured and the wavefront distortions at the sample position were analyzed. A ...
The design and operating principles of a focusing x-ray monochromator are described. Consistent with extended x-ray absorption fine structure (EXAFS) applications it allows rapid tuning while maintaining high energy resolution and a fixed focus at the sample. The basic instrument consists of two opposing two crystal monochromators with ...
A newly designed cryogenically cooled, thin Si crystal monochromator was tested at the European Sychrotrons Radiation Facility (ESRF) beamline BL3. It exhibited less than 1 arcsec of thermal strain up to a maximum incident power of 186 W and average power...
We report on a design and on some experimental results for the performance of a new high energy resolution monochromator. It is a large channel-cut Si crystal with a 197 mm separation between the two faces designed to operate in a near-backscattering regime. The device was tested as a second monochromator on Sector 3 of the Synchrotron ...
A tunable, double multilayer x-ray monochromator has recently been implemented on the National Synchrotron Light Source (NSLS) X25 wiggler beam line. It is based on a parallel pair of tungsten-boron-carbide multilayer films grown on silicon substrates and purchased from Osmic, Inc. of Troy, Michigan, USA. It acts as an optional alternative to the conventional double silicon ...
The new inclined crystal geometry has been successfully used in high heat load X-ray monochromator tests. The important aspect of this geometry is that from a diffraction point of view, when properly aligned, is is a symmetric Bragg reflection; i.e., b = k{sub i} . n/k{sub out}.n = {minus}1. An interesting result of this geometry is that with a single ...
A sagittal focusing monochromator which utilizes a bimetallic strip as its active focusing member has been designed and has undergone preliminary testing. The crystal bender is very easy to use as only setting the temperature of the bimetallic strip is ne...
Low temperature luminescence anomalies of MnF2 crystals were studied. The luminescence spectra were studed by means of a prism monochromator. The intensity of luminescence was recorded by the EEU-17A photomultiplier. The three optical transitions in MnF2 ...
The intensity of a monoenergetic neutron beam obtained by reflection from a crystal monochromator is very often decreased due to the additional so- called parasitic scattering. Since this effect gives several percent fluctuations of the intensity, it must be taken into account in precise measurements. In particular, it is important in neutron ...
The first crystal of the Brown-Hower x-ray monochromator of the LBL-EXXON 54 pole wiggler beamline at Stanford Synchrotron Radiation Laboratory (SSRL) is subjected to intense synchrotron radiation. To provide an accurate thermal/structural analysis of the existing monochromator design, a finite element analysis (FEA) was performed. A ...
Silicon and diamond monochromators (crystals), often used in the Advanced Photon Source X-ray beamlines, require a good quality surface finish and stress-free installation to ensure optimal performance. The device used to mount the crystal has been shown to be ajor contributing source of stress. In this case, an adjustable mounting ...
General properties of monochromators are discussed, and some useful formulas are given for optical design. Only the Rowland reflection grating, whose groove pattern consists of the intersection of the substrate surface with a set of parallel equispaced planes, is considered. The focusing properties of a toroidal grating are discussed. Some aberrations are briefly described, ...
Big changes in resistivity along with the changing of local structure in some oxide systems, such as high-temperature superconductors and colossal magnetoresistance system, strongly suggest the need of a systematic investigation of their local electronic and atomic structures. In this work we present the high-resolution X-ray emission spectra and the spin-polarized X-ray absorption near-edge ...
Measurements of the harmonic content from single and double crystal silicon monochromators have been made in the 20 to 100 keV at the X17 Superconducting Wiggler Beamline at the NSLS. These measurements are compared with calculations which estimate the monochromatic beam harmonic content and the detection system efficiency with good agreement. At high ...
Due to its outstanding thermal properties, diamond is an attractive alternative to silicon as a monochromator material for high intensity X-ray beams. To date, however, the practical applications have been limited by the small size and relatively poor crystallographic quality of the crystals available. The ESRF Diamond Project Group has studied the ...
The preparation of intercalated graphite compounds is now well established at the Institut Laue Langevin (ILL). We are able to manufacture several types of intercalated crystals, such as KC8, RbC8, KC24 and RbC24 compounds, in large quantities and in a reproducible manner. Even though the mosaic distribution is large, these compounds exhibit a high neutron peak reflectivity of ...
Pre-polished Ge(111) single-crystal wafers were deformed just below the melting temperature to prepare point-focusing Johansson monochromator crystals. The (111) lattice plane had curvature 2R in the focusing plane and R perpendicular to it, with a hemispherical inner surface with a radius of R = 600 mm. By using Cu Kalpha radiation, ...
Plastically deformed Si-crystal wafers were characterized by monochromatic neutron diffraction. During the cylindrically curved deformation, a resolution-limit Bragg peak changes into a box-type angular profile in accordance with the bulk curvature, associated with an enhancement in the angle-integrated intensity (I?). Stacking such wafers is efficient in amplifying I? ...
Internally cooled monochromator crystals have been successfully fabricated and tested with synchrotron radiation. A single block of silicon was parted in the middle and grooves on a mm scale were cut into one half. The two blocks were then bonded back together with a silver-glass die attach paste. After firing in air at 430 /degree/C, the composite ...
A high-energy double-crystal x-ray monochromator has been constructed for use on the X-17 beam line at the National Synchrotron Light Source (NSLS). Its design is based on the boomerang'' right angle linkage, and features a fixed exit beam, a cooled first crystal, and an energy range of 8--92 keV. The entire ...
An ultra-high vacuum double-crystal fixed-exit x-ray monochromator has been designed and built for soft X-ray (0.8-8 KeV) spectroscopic studies. This unit, currently installed at the NSLS on beamline X-11B, uses two crystal carousels, each of which can hold four different crystals to allow ...
Preserving the high source brightness of the third generation of synchrotron radiation facilities will require that thermal and pressure deformations of the monochromator crystals be maintained within a few arc- seconds. Recent experiments at the National Synchrotron Light Source (NSLS) have demonstrated the potential of adaptive ...
Critical UV applications such as disinfections and dermatological treatments call for accurate UV spectral irradiation measurements. Single monochromators and spectrographs are not able to provide satisfying accuracy due to poor stray light rejection. The main drawbacks of a double monochromator scanning system are the need for motion synchronization, the ...
YB(sub 66), a complex binary semiconducting compound, cubic in crystal structure with a cell parameter of 23.44 (Angstrom), has been singled out as a potentially useful soft x-ray monochromator for dispersing synchrotron radiation. There is no intrinsic a...
A three-axis spectrometer is described in which the monochromator and the analyzer crystals are curved both in the vertical and in the horizontal direction. Figures are given for the resolution in energy and in momentum transfer of this instrument. It is demonstrated that valuable data can be obtained on very small samples. It is further shown that ...
The intensity of a monoenergetic neutron beam obtained by reflection from a crystal monochromator is very often decreased due to the additional so- called parasitic scatterings. Since this effect gives several percent fluctuations of the intensity, it has to be taken into account in precise measurements. In particular it is important in neutron ...
Three water-cooled pin-post monochromators, to be used on a wiggler beamline at the Advanced Photon Source (APS), were built with the heat exchanger engineered to provide very high heat transfer. The geometry of the heat exchanger as well as calculated data on the heat transfer will be presented. Before using the monochromators on the beamline, they were ...
The characterization and initial operation of a materials science EXAFS beam line at the NSLS is described. This line has a unique combination of components including a 4-crystal focusing monochromator and SiC collimating mirror. Discussion of the monochromator will include a comparison with conventional two ...
We present initial characterization results of a novel ultra-high-vacuum-compatible artificial channel-cut monochromator that has been installed as part of undulator beamline 8-ID-I at the Advanced Photon Source. We present details of the mechanical design and control-system implementation of the new device. The monochromator has been designed to meet the ...
We present design and characterization results of a novel ultra-high-vacuum-compatible artificial channel-cut monochromator that has been installed at the undulator beamline 8-ID-I at the Advanced Photon Source. The monochromator has been designed to meet the challenging stability and optical requirements of the x-ray photon correlation spectroscopy ...
Perfect single crystals of silicon are used to monochromate the high-intensity X-ray beams in the Advanced Photon Source at Argonne National Laboratory. Depending on the crystal geometry and the insertion device, the crystal may absorb anywhere from several hundred watts to in excess of a thousand watts. To ...
A fixed-exit double crystal monochromator based on one rotation has been designed for an absorption spectroscopy beamline. The first crystal is mounted in the center of rotation, while the second crystal is translated by simple mechanical means. This change of the gap distance d keeps the beam offset constant. The ...
A novel ultra-high-vacuum (UHV)-compatible x-ray monochromator has been designed and commissioned at the undulator beamline 8-ID-I at the Advanced Photon Source (APS) for x-ray photon correlation spectroscopy applications. To meet the challenging stability and x-ray optical requirements, the monochromator integrates two new precision angular positioning ...
High-energy X-ray focusing with bent-crystal monochromators is known to be hampered by so-called depth or crystal-thickness aberrations. A theoretical model of focus broadening based on the geometrical theory of X-ray diffraction in slightly deformed crystals is presented and compared with experimental data. First, ...
SPring-8 standard double-crystal monochromators containing water-cooled crystals were stabilized to a sufficient level to function as a part of optics components to supply stable microfocused x-ray beams, by determining causes of the instability and then removing them. The instability was caused by two factors-thermal deformation of ...
High energy wigglers produce extremely high total powers. For example, the insertion device for one beamline of the Basic Energy Sciences Synchrotron Research Center (BESSRC) is an elliptical multipole wiggler (EMPW) which can generate circularly polarized X-rays on axis and produces a total power of {approximately}8 kW. This insertion device will be used to simultaneously provide x-rays to three ...
Silicon crystals at room temperature employed as x-ray monochromators on synchrotron radiation beamlines, when subjected to high-power-density loading, suffer thermal distortions which compromise their x-ray diffraction efficiency and result in a reduction of the inherent brilliance of the synchrotron beam. At cryogenic temperatures however (below 150 K), ...
Active-matrix liquid crystal displays (AMLCDs) are light-modulating devices that generate images by differentially transmitting a nearly uniform luminous field provided by a backlight. While emissive displays exhibit a quasi-Lambertian emission with almost constant contrast at off-normal viewing, the anisotropy of the electro-optic effect that controls light transmission in ...
YB(66)(400) crystals present a new advance in monochromator crystals suitable for use at energies below 2 keV. In this paper a comparison of their performance with that provided by the more usual beryl and quartz crystals, which cover the same energy range, is presented. In general, the YB(66) ...
A high-precision water-cooled, small offset, double crystal monochromator has been developed for the Advanced Photon Source (APS) UNICAT Sector 34 beamline. The design incorporates the supports and gravity feed water cooling of two diamond or silicon crystals correctly positioned about a common rotation axis so that the incident and ...
A high-precision cryogenically-cooled crystal monochromator has been developed for the APS diagnostics beamline. The design permits simultaneous measurements of the particle beam size and divergence. It provides for a large rotation angle, {minus}15{degree} to 180{degree}, with a resolution of 0.0005{degree}. The roll angle of the ...
Multiple reflection effects resulting in Umweganregung or Aufhellung have been studied in elastically bent perfect silicon single-crystals which are often used for focusing monochromators or analyzers. It has been proved that under certain conditions strong multiple reflections with intensities comparable or even higher than those corresponding to single ...
A new Cowan type'' double-crystal monochromator, based on the boomerang design used at National Synchrotron Light Source (NSLS) beamline X-24A, has been developed for beamline 9.3.1 at the Advanced Light Source (ALS), a windowless ultrahigh vacuum beamline covering the 1--6 keV photon-energy range. Beamline 9.3.1 is designed to ...
Recently, a new type of cryogenically cooled high heat load monochromator was proposed and, developed at Argonne National Laboratory and tested at European Synchrotron Radiation Facility (ESRF.) These tests showed that powers of 153 W and power densities ...
The next generation of synchrotron radiation sources will produce very high power and power density x-ray beams. For example, the Advanced Photon Source (APS) under construction at Argonne National Laboratory will produce beams containing up to 5 kill of power and peak normal power densities in excess of 150 W/mm{sup 2}. Normally, the first optical component to intercept the x-ray beam is a ...
Raman scattering has been observed from the hydroxyl ion in NaCl, Kcl, and KBr crystals. The measurements were made using an argon ion laser as a light source and a tandem double monochromator with photoelectric detection. A Raman emission attributed to t...
A sapphire backscattering monochromator with 1.1?(1)?meV bandwidth for hard X-rays (20-40?keV) is reported. The optical quality of several sapphire crystals has been studied and the best crystal was chosen to work as the monochromator. The small energy bandwidth has been obtained by decreasing the ...
During the period of this report the photon power of Stanford Synchrotron Radiation Project (SSRP) was roughly doubled with the addition of the new second beam line. This beam initially started up with the second channel-cut crystal monochromator system d...
A double crystal-type monochromator has been installed at the ANTARES facility at FRM II, Munich, close to the collimator where the beam size is still only a few centimetres. Using this new set-up, it is now possible to perform high-resolution monochromatic neutron imaging in a wavelength range from 2.7 to 6.5 � with a wavelength resolution ??/? of 4-1%. ...
ABS>An experimental arrangement that uses two bent-crystal monochromators in transmission rather than in reflection to reduce background scattering, virtually eliminate parasitic scattering beyond an angle of about 10' of arc, and to minimize the thermal diffuse scattering near the Bragg angle without using narrow slits is described. ...
This paper describes some of the aspects of the cryogenic optics program at the Advanced Photon Source (APS). A liquid-nitrogen-cooled, high-vacuum, double crystal monochromator is being fabricated at Argonne National Laboratory (ANL). A pumping system capable of delivering a variable flow rate of up to 10 gallons per minute of pressurized liquid nitrogen ...
A vacuum-compatible double-crystal monochromator with constant exit-beam height has been installed and operated for several years at beamline BL7A at the UVSOR facility at the Institute for Molecular Science, Okazaki, Japan, The beamline is used both for the photons from a normal bending-magnet section and those from a 4 T superconducting three-pole ...
We report measurements of the thermal expansion of high-purity single crystal sapphire along the a and c directions. The data were acquired using a thermal expansion cell that is constructed of fused silica with a relative resolution of approximately 3x10-9. Comparison will be made to existing literature values determined from dilatometry and high-resolution x-ray diffraction. ...
Perfect crystals in transmission (Laue) geometry can be used effectively for x-ray monochromators, and moreover, perfect Laue crystals show an interesting focusing effect when the incident beam is white and divergent. This focusing is directly dependent on the incident beam divergence and on the diffraction profile width of the ...
This paper describes a novel six-circle diffractometer dedicated to diffraction and diffuse scattering measurements from single crystals. The goniometer allows also the study of protein structures with a bidimensional detector. This complex instrument is set up on a beam line (bending magnet) at LURE DCI (Orsay, France). A double crystal ...
Protein crystallographers are nowadays regular users of synchrotron radiation (SR) facilities for several applications. The goal of majority of users is simply to extract more accurate, higher resolution data from existing crystals; they use monochromatic radiation and the rotation method, in order to get a complete survey of the reciprocal space in a short time. In fact the ...
In human medical imaging, the performance of the monitor used for image reporting has a substantial impact on the diagnostic performance of the entire digital system. Our purpose was to compare the display quality of different monitors used in veterinary practice. Two medical-grade gray scale monitors (one cathode-ray tube [CRT], one liquid crystal display [LCD]) and two ...
The use of water-cooling channels in silicon x-ray monochromators for the Cornell High Energy Synchrotron Source (CHESS) high power wiggler beamlines has been studied by finite element analysis. The efficiency from channels of different dimensions, ranging from 25 mm to 2 mm width and 5 mm depth, has been calculated. The new crystals are designed to ...
The design and performance of a novel ultra-high-vacuum-compatible artificial channel-cut monochromator that has been commissioned at undulator beamline 8-ID-I at the Advanced Photon Source are presented. Details of the mechanical and optical design, control system implementation and performance of the new device are given. The monochromator was designed ...
Cryogenically cooled silicon monochromators have found wide application at the Advanced Photon Source (APS) and other third-generation synchrotron radiation facilities. Currently, 17 insertion device beamlines at the APS are implementing cryogenic, silicon double-crystal monochromators (DCM) as the first optical element. Recently, ...
Cryogenically cooled silicon monochromators have found wide application at the Advanced Photon Source (APS) and other third-generation synchrotron radiation facilities. Currently, 17 insertion device beamlines at the APS are implementing cryogenic, silicon double-crystal monochromators (DCM) at the first optical element. Recently, ...
Simplicity, symmetric design, variable energy range, and support for both sides of the crystals are features of a new fixed-exit crystal monochromator that we have designed, built and tested. It is less complex; therefore it is less expensive to build, easier to understand, and easier to maintain. All high-precision ground surfaces ...
Outlined are design features of a versatile high-resolution two-axis diffractometer that is being constructed for operation at the Photon Factory as an Australian national facility. The instrument features optional use of multiple-imaging plates on a translating cassette to allow rapid recording of an almost complete range of data covering both the high-angle and small-angle scattering regime or ...
The performance of sagittal focusing for hard X-rays with a cylindrical bent crystal at the SPring-8 is described. The bending mechanism is designed for the SPring-8 standard bending-magnet beamlines. Two-dimensional focusing is achievable by combining sagittal horizontal focusing and vertical focusing mirror. The results underline that the two-dimensional focusing was ...
The construction of a universal double-crystal neutron spectrometer of high precision is described. The instrument can be used for double- or single- crystal neutron spectrometry, as a neutron monochromator for cross section measurements in the range 0.03 to 10 ev, and as a diffractograph for powder diffraction crystallographic ...
We present the present status and recent advances in diffractive neutron optics at the ILL. Very high-quality copper crystals with intrinsic mosaics of the order of 1? can now be produced which is of interest for the reproducible production of higher-mosaic anisotropic crystals for neutron monochromators and potentially for a gamma-ray ...
For the stabilization of the SPring-8 double-crystal monochromator with water-cooled inclined-cut silicon crystals, we have changed the water path of the first crystal, remodeled the crystal holders and attached x-ray and electron shield parts. The improvements are effective to supply ...
To predict the performance of the cryogenically cooled silicon crystal, intensive studies have been carried out to sort out the influences of various parameters, such as heat load power and power distribution, cooling coefficient, and beam size. The thermal slope error of the crystal is calculated by finite element modeling. Quadratic law was applied to ...
Recent advances in liquid crystal technology have enabled us to construct tunable birefringent filters with bandwidths between approximately 0.1 nm and 50 nm. The center wavelength of these filters can be selected electronically, in a few tens of milliseconds, with no moving parts. These liquid crystal tunable filters (LCTF's), together with ...
Recent advances in liquid crystal technology have enabled us to construct tunable birefringent filters with bandwidths between approximately 0.1 nm and 50 nm. The center wavelength of these filters can be selected electronically, in a few tens of milliseconds, with no moving parts. These liquid crystal tunable filters (LCTF's), together with existing CCD ...
A new set-up is reported of an indirect cryogenic cooling system for a double-crystal monochromator which runs on the BM30b/FAME beamline at the ESRF (Grenoble, France). This device has been conceived to limit the vibrations on the first diffracting crystal and to maintain it at a constant temperature. These points are crucial for ...
Recently, preliminary measurements were taken to demonstrate the quality of narrow spectral band, two-dimensional imaging of a specially-shaped quartz x-ray diffracting crystal. The evaluation consisted of back-illuminating a fine wire mesh, located off the focal circle of the crystal, with a monochrome of aluminum K radiation and ...
The effect of ultrasound (US) on neutron Laue's diffraction is studied for perfect and deformed crystals. In a perfect crystal the oscillations of relative diffraction intensity were observed, which depend on the ultrasound wave amplitude. In a deformed crystal the ultrasound distorts the adiabatic motion of the image points along the ...
An optically transparent furnace having a detection apparatus with a pedestal enclosed in an evacuated ampule for growing a crystal thereon is disclosed. Temperature differential is provided by a source heater, a base heater and a cold finger such that material migrates from a polycrystalline source material to grow the crystal. A quartz halogen lamp ...
An optically transparent furnace (10) having a detection apparatus (29) with a pedestal (12) enclosed in an evacuated ampule (16) for growing a crystal (14) thereon. Temperature differential is provided by a source heater (20), a base heater (24) and a cold finger (26) such that material migrates from a polycrystalline source material (18) to grow the ...
The results of the latest high-heat-load studies made on the APS/CHESS prototype undulator are summarized. Four different crystals were tested: two slotted, symmetrically cut silicon crystals and a core-drilled, asymmetrically cut silicon crystal and a diamond crystal that was jet cooled using water. The purpose of ...
New concepts for time-resolved x-ray absorption spectroscopy using the quick-extended x-ray absorption fine structure (QEXAFS) method are presented. QEXAFS is a powerful tool to gain structural information about, e.g., fast chemical reactions or phase transitions on a subsecond scale. This can be achieved with a monochromator design that employs a channel-cut ...
A system for area-beam energy-subtraction monochromatic radiography was developed and tested. It utilizes a bent Laue crystal monochromator developed at the National Synchrotron Light Source (NSLS), and a compact rotating anode X-ray source developed at the Science Research Laboratory (SRL). The K(alpha) characteristic lines (both K(alpha 1) and K(alpha 2) ...
Powder diffraction patterns from SRM Si640b are used to calibrate the energy scale for two experiments using a monochromated synchrotron X-ray beam in the high energy region 38-50 keV. The energy of the beam is determined to accuracies between 0.0007% and 0.07% of the beam energy. Uncertainties in the energy scale are reduced by correcting for the zero offset angle of the ...
A new ``Cowan type`` double-crystal monochromator, based on the boomerang design used at NSLS beamline X-24A, has been developed for beamline 9.3.1 at the ALS, a windowless UHV beamline covering the 1-6 keV photon-energy range. Beamline 9.3.1 is designed to simultaneously achieve the goals of high energy resolution, high flux, and high brightness at the ...
To test the efficiency of time-of-flight (TOF) spectroscopy on a long pulse spallation source a prototype of a TOF monochromator instrument for powder diffraction (within the resolution range of about 1-5�10-3 for /?d/d) is installed on the reactor source at KFKI in Budapest. Due to the fact that the considered instrument uses choppers to generate a short neutron pulse and ...
We present a temperature stabilised high resolution sapphire backscattering monochromator. The device consists of a sapphire crystal inside a cold nitrogen gas cooled, temperature stabilised chamber with a passively temperature stabilised screen. The achieved temperature stability of {+-}2mK allows for an energy resolution of {delta}E/E {<=} 10-7 at ...
This note summarizes the results of the single crystal monochromator high-heat-load tests performed at the CHESS F-2 wiggler station. The results from two different cooling geometries are presented: (1) the ``pin-post`` crystal and (2) the ``criss-cross`` crystal. The data presented were taken in August 1993 ...
The need to monochromatize and focus X-rays emitted into appreciable horizontal apertures by storage ring sources (bending magnets and wigglers) leads to the design of focusing monochromators. In order to optimize their design, it is important to understand the combined effect of focusing and diffraction of the flux available at the sample. We analyze here the combined effect ...
The desire for increasingly smaller X-ray beams for macromolecular crystallography experiments also stimulates the need for improvements in beam stability. There are numerous sources of instability, which influence beam quality on the micron-size scale. Typically, the most problematic source is thermal drift within the double crystal monochromators. In ...
We have used a direct optical measurement of the distortion of the first silicon crystal of the CHESS A2 monochromator. The total X-ray power absorbed by the crystal was in the range of 2 to 190 Watts. The X-ray powers measured by a bolometer were in good agreement with the XOP calculations. In-situ optical measurements were used to ...
We describe the mechanical design of a medical-imaging monochromator for the Multiple Energy Computed Tomography (MECT) project at the X17B superconducting beamline of the NSLS. The monochromator consists of two independent two-crystal Laue-Laue units in tandem, with the option of using a Laue-Bragg/Bragg-Laue configuration. It ...
The inclined double crystal monochromator arrangement is very effective in handling high heat loads and holds considerable promise as a monochromator for undulator beams at third generation synchrotrons. Results for the ideal inclined crystal case have been obtained by dynamical diffraction calculations, and ...
A two-crystal x-ray monochromator was built at LNLS. It is based on the Golovchenko (J. A. Golovchenko, R. A. Levesque, and P. L. Cowan, Rev. Sci. Instrum. {bold 52}, 51 (1981)) geometry with one rotation and two translations in order to tune the wavelength and keep constant the position of the monochromatic beam, respectively. The Bragg angle can vary ...
A new method for calibrating the energy scale of x-ray absorption spectra from an energy dispersive spectrometer has been developed. Distinct features in the diffracted intensity of the curved silicon crystal monochromator have been assigned to multiple-beam diffraction. The photon energies of these structures can be calculated if the precise spacing of ...
The design of monochromators for x-ray applications, using either standard laboratory sources on synchrotron radiation sources, requires a knowledge of the reflectivity of the crystals. The reflectivity depends on the crystals used, the geometry of the reflection, the energy range of the radiation, and, in the present case, the ...
An Advanced Photon Source (APS) Collaborative Access Team (CAT) Workshop on Beamline Optical Designs was held at Argonne National Laboratory on July 26--27, 1993. The goal of this workshop was to bring together experts from various synchrotron sources to provide status reports on crystal, reflecting, and polarizing optics as a baseline for discussions of issues facing optical ...
In this work, we intend to relate the mineral to non-mineral bone scattering intensity ratio with the bone-mineral density (BMD) reduction. In this way, EDXRD can be a novel technique to measure BMD loss in function of the mineral and non-mineral scattering intensity. The scattering profiles were obtained at Laborat�rio Nacional de Luz S�ncrotron (LNLS) at the X-ray diffraction beamline XD2. A ...
The crystal and molecular structure of amidithion (O,O-dimethyl S-(N-2-methoxyethylcarbamoylmethyl) phosphorodithioate), (CH/sub 3/O)/sub 2/P(S)SCH/sub 2/C(O)NHC/sub 2/H/sub 4/OCH/sub 3/, has been determined by three-dimensional x-ray analysis. The compound crystallizes in the monoclinic space group P2/sub 1//c with a = 10.975 (3), b = 9.335 (2), c = ...
The inclined crystal geometry has been suggested as a method of reducing the surface absorbed power density of high-heat-load monochromators for third-generation synchrotron radiation sources. Computer simulations have shown that if the crystals are perfectly aligned and have no strains then the diffraction properties of a pair of ...
The total neutron cross section of exp 159 Tb has been measured in the energy range from 0.062 to 1 eV with a crystal spectrometer using the Be(1011) crystal planes as a monochromator. The data in the left wing of the first neutron resonance in exp 159 Tb...
photonic crystal unit cells.11 III. THEORETICAL CONCEPTS For the pump beam incident along the pore axis of a photonic band gap can be redshifted via the Kerr effect with a pump beam at 2.0 m. For a pump wavelength the entry point of the pump beam. The reflected probe beam is passed through a 0.25 mm monochromator
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A newly designed, cryogenically cooled, thin Si crystal monochromator was tested at the European Synchrotron Radiation Facility (ESRF) beamline BL3. It exhibited less than 1 arcsec of thermal strain up to a maximum incident power of 186 W and average powe...
The neutron optics of three-axis spectrometers with curved ideal monochromator and analyser crystals is considered. The computation technique allows for both real-and reciprocal-space focusing effects. The possibility is revealed of obtaining very high re...
A new design of a bent crystal analyzer for high energy resolution inelastic X-ray scattering has been recently proposed. It has been theoretically predicted that an analyzer with reflecting planes at a certain angle with respect to a crystal surface, bent with two different radii of curvature, will have the same energy resolution as a perfect ...
The objective of this study was to compare the contrast-detail performance of five different commercial liquid crystal displays (LCDs) to other LCD and cathode-ray tube (CRT) displays for medical applications. A contrast-detail phantom, supplemented with 5 in. of acrylic, was imaged on a commercial digital radiographic system using techniques comparable to chest radiography. ...
The properties of a detuned nondispersive Si(111) double crystal monochromator were studied by using the ray tracing method. The program used was the PC version of shadow V2.3.3 with gui V1.2. This article concentrates on detuning of the second crystal since detuning of the first crystal causes a larger shift of ...
Automatic tuning of double-crystal monochromators presents an interesting challenge in software. The goal is to either maximize, or hold constant, the throughput of the monochromator. An additional goal of the software feedback is to disable itself when there is no beam and then, at the user's discretion, re-enable itself when the beam ...
For the new LNLS dispersive beam line it was designed a single-crystal monochromator and a 2-theta arm. The monochromator uses a new bender design assembled on the top of an in-vacuum HUBER goniometer. This bender is able to apply independent torque on each extremity of the crystal in a way that changes in the ...
For some x-ray experiments, only a fraction of the intense central cone of x-rays generated by high-power undulator sources can be used; the x-ray source emittance is larger than the useful emittance for the experiment. For example with microfocusing optics, or for coherence experiments, x-ray beams with cross sections less than 0.1 mm{sup 2} are desirable. With such small beams, the total thermal ...
First optical elements at third-generation, hard x-ray synchrotrons, such as the Advanced Photon Source (APS), are subjected to immense heat fluxes. The optical elements include crystal monochromators, multilayers and mirrors. This paper presents a mathematical model of the thermal strain of a three-layer (faceplate, heat exchanger, and baseplate), ...
A systematic study is presented in which multilayers of different composition (W/Si, Mo/Si, Pd/B(4)C), periodicity (from 2.5 to 5.5 nm) and number of layers have been characterized. In particular, the intrinsic quality (roughness and reflectivity) as well as the performance (homogeneity and coherence of the outgoing beam) as a monochromator for synchrotron radiation hard X-ray ...
Position sensitive detectors (PSDs) have been in use at MURR for nearly 20 years, while focusing monochromators have been developed only during the past six years. Incremental improvements in both systems have led to a high resolution powder diffraction system with a fast data acquisition rate for small samples (typically one gram of material). This is achieved by matching ...
The University of Wisconsin-Madison Physical Sciences Laboratory (PSL) has designed and built two new types of double crystal monochromator (DCM): the Compact DCM and the Broomstick DCM. The Compact DCM has a single rotational stage and features a frame footprint only 0.74 m by 0.84 m, with a distance of only 0.35 m from beam centerline to the back of the ...
At CHESS, 2500 W total are absorbed by the first crystal of the double bounce monochromators located at the A2 and F2 wiggler beamlines. In order to dissipate this absorbed power and deliver the highest X-ray flux to an end station, we have explored the technique of internally cooling the silicon first crystals with water channels. ...
At CHESS, 2500 W total are absorbed by the first crystal of the double bounce monochromators located on the A2 and F2 wiggler beamlines. In order to dissipate this absorbed power and deliver the highest x-ray flux to an end station, we have explored the technique of internally cooling the silicon first crystals with water channels. ...
Nuclear reactor slow neutron spectra obtained by the use of a crystal monochromator contain a number of irregular fluctuations in the form of inverted peaks due to fluctuations in the reflectivity of the crystal. It is shown that these fluctuations are due to Bragg reflection of neutrons by reflecting planes other than that ...
Nuclear-reactor slow-neutron spectra obtained by the use of a crystal monochromator contain a number of irregular fluctuations in the form of inventsd peaks, due to fluctuations in the reflectivity of the crystal. It is shown that these fluctuations are due to Bragg reflection of neutrons by reflecting planes other than that ...
The design and operation of beam line X-11A at the NSLS is described. It employs a unique optical design using a two/four crystal monochromator and a SiC collimating mirror. In either two or four crystal mode a sagittal focusing crystal allows collection of up to 5 mrad of horizontal divergence. Two techniques for ...
Both simulations and recent experiments conducted at the Advanced Photon Source showed that the performance of liquid-nitrogen-cooled single-silicon crystal monochromators can degrade in a very rapid nonlinear fashion as the power and for power density is increased. As a further step towards improving the performance of silicon optics, we propose cooling ...
We have developed a new design for a cryogenically cooled monochromator employing a thin-crystal strategy which is capable of handling the central-cone power of the Advanced Photon Source's undulator A at closed gap and at the full design current of 300 mA. We have designed and fabricated a Si (111) crystal which has a thin ...
We have developed a new design for a cryogenically cooled monochromator employing a thin-crystal strategy which is capable of handling the central-cone power of the Advanced Photon Source`s Undulator A at closed gap and at the full design current of 300 mA. We have designed and fabricated a Si (111) crystal which has a thin section ...
The insertion-device-based, third-generation, synchrotron radiation sources now under construction in Europe, the USA, and Japan bring new opportunities and challenges in the design and manufacture of x-ray optics. These high brightness sources provide new opportunities to overcome some of the outstanding problems associated with nuclear resonant monochromatization of synchrotron radiation. New ...
The third generation of synchrotron radiation sources, such as the Advanced Photon Source (APS), will provide users with a high brilliance x-ray beam with high power and power densities. In many cases, the first optical component to intercept the x-ray beam is a silicon-crystal monochromator. Due to extreme heat loading, the photon throughput and ...
We report on the performance of a double crystal monochromator exposed to large heat loads from a 6 pole wiggler magnet running at 15.6 kG peak field and a 5.3 GeV electron beam. This source of synchrotron radiation can produce between 1.8 and 4.5 kW of X-ray power depending on beam conditions. Various single crystals of silicon have ...
When a wide fan-shaped x-ray beam is diffracted by a bent crystal in the Laue geometry, the profile of the diffracted beam generally does not appear as a straight line, but as a line with its ends curved up or curved down. This effect, referred to as 'beam-smiling', has been a major obstacle in developing bent-Laue crystal ...
