Preparation of bent crystals as high-efficiency optical elements for hard x-ray astronomy

The Canadian Macromolecular Crystallography Facility (CMCF) at the Canadian Light Source (CLS) is a suite of fully automated beamlines, 08ID-1 and 08B1-1 [1]. It serves over 60 Canadian groups plus academic and commercial users in the US. Besides remote data collection, we offer Mail-In service where data are collected by CMCF staff. Beamline 08B1-1 has been in operation since 2011 and beamline 08ID-1 since 2006. When beamline 08ID-1 was designed, over 10 years ago, small crystals were defined as having sizes of 50-100 μm. Today, the most challenging experiments require more intense X-ray beams that can be focused to accommodate much smaller crystal sizes of less than 5 μm with flux on the order of 10^11 photons/s. To reach these stringent parameters, a new more powerful source of X-rays will be required, which will be provided by a longer small-gap in-vacuum undulator (SGU). To accommodate the higher power levels and to focus X-rays to a smaller focal spot with a high degree of spatial and temporal stability, the existing X-ray optical elements need to be upgraded. The remaining components of the project include a 5-axis alignment table for improving alignment of small samples with the microbeam, a high-efficiency robotic sample-changer and a single-photon X-ray detector. Several options for the new design will be discussed. These developments are consistent with the current direction of structural biology research at the CLS [2]. Since 2006 over 225 (240) papers and 400 (444) PDB deposits reported data collected at beamline 08ID-1. Parentheses indicate the total number for the CMCF. Many of these have been published in very high impact journals such as N. Engl. J. Med., Nature, Cell, Science, PNAS, among others (http://cmcf.lightsource.ca/publications/).

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Combined Microstructure X-Ray Optics; Multilayer Diffraction Gratings

MRS Proceedings ◽

10.1557/proc-103-307 ◽

1987 ◽

Vol 103 ◽

Cited By ~ 7

Author(s):

Troy W. Barbee

Keyword(s):

High Efficiency ◽

Extreme Ultraviolet ◽

Diffraction Gratings ◽

Experimental Results ◽

Optical Elements ◽

Ray Optics ◽

X Ray ◽

Spectral Ranges

ABSTRACTMultilayers are man-made microstructures engineered to vary in depth that are now of sufficient quality to be used as x-ray, soft x-ray and extreme ultraviolet optics. Gratings are in-plane man-made microstructures which have been used as optic elements for most of this century. Joining of these two optical elements to form combined microstructure optics has the potential for greatly enhancing both the resolution and the throughput attainable in these spectral ranges. Experimental results for multilayer gratings are presented and discussed. It will be demonstrated that multilayer diffraction gratings act as x-ray prisms and are high efficiency dispersion elements.

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General method to calculate the elastic deformation and X-ray diffraction properties of bent crystal wafers

IUCrJ ◽

10.1107/s2052252520014165 ◽

2021 ◽

Vol 8 (1) ◽

pp. 102-115

Author(s):

Ari-Pekka Honkanen ◽

Simo Huotari

Keyword(s):

Stress And Strain ◽

Light Sources ◽

X Ray Diffraction ◽

Optical Elements ◽

Theoretical Understanding ◽

Strain Fields ◽

X Ray ◽

Bent Crystal ◽

Bent Crystals ◽

General Method

Toroidally and spherically bent single crystals are widely employed as optical elements in hard X-ray spectrometry at synchrotron and free-electron laser light sources, and in laboratory-scale instruments. To achieve optimal spectrometer performance, a solid theoretical understanding of the diffraction properties of such crystals is essential. In this work, a general method to calculate the internal stress and strain fields of toroidally bent crystals and how to apply it to predict their diffraction properties is presented. Solutions are derived and discussed for circular and rectangular spherically bent wafers due to their prevalence in contemporary instrumentation.

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High diffraction efficiency in crystals curved by surface damage

Journal of Applied Crystallography ◽

10.1107/s0021889813022954 ◽

2013 ◽

Vol 46 (6) ◽

pp. 1576-1581 ◽

Cited By ~ 17

Author(s):

Claudio Ferrari ◽

Elisa Buffagni ◽

Elisa Bonnini ◽

Dusan Korytar

Keyword(s):

Surface Damage ◽

Curvature Radius ◽

Optical Elements ◽

X Ray ◽

Integrated Intensity ◽

Damage Process ◽

Extinction Length ◽

Lattice Planes ◽

Bent Crystals ◽

Strong Curvature

Diffraction profiles of curved Si and GaAs crystals obtained by a controlled damage process on one side of planar crystals have been investigated at X-ray energiesE= 17, 59 and 120 keV. AtE= 17 and 59 keV in the condition of slight curvature, that is when the diffracting plane bending over the extinction length is lower than the Darwin width, the Laue diffraction profiles with lattice planes parallel or inclined with respect to the curvature radiusRshow an enhancement of integrated intensity proportional to 1/R, much larger than in the corresponding perfect bent crystals. AtE= 120 keV, in the condition of strong curvature, the crystals behave as bent perfect crystals with integrated intensity corresponding to that of a mosaic crystal. These crystals are proposed as optical elements for focusing hard X-ray beams.

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Complete Ring Artifacts Reduction Procedure for Lab-Based X-ray Nano CT Systems

Sensors ◽

10.3390/s21010238 ◽

2021 ◽

Vol 21 (1) ◽

pp. 238

Author(s):

Jakub Šalplachta ◽

Tomáš Zikmund ◽

Marek Zemek ◽

Adam Břínek ◽

Yoshihiro Takeda ◽

...

Keyword(s):

High Efficiency ◽

Image Inpainting ◽

Simulated Data ◽

Complementary Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

Detection Accuracy ◽

Reduction Procedure ◽

X Ray ◽

Artifacts Reduction ◽

Ct Data

In this article, we introduce a new ring artifacts reduction procedure that combines several ideas from existing methods into one complex and robust approach with a goal to overcome their individual weaknesses and limitations. The procedure differentiates two types of ring artifacts according to their cause and character in computed tomography (CT) data. Each type is then addressed separately in the sinogram domain. The novel iterative schemes based on relative total variations (RTV) were integrated to detect the artifacts. The correction process uses the image inpainting, and the intensity deviations smoothing method. The procedure was implemented in scope of lab-based X-ray nano CT with detection systems based on charge-coupled device (CCD) and scientific complementary metal–oxide–semiconductor (sCMOS) technologies. The procedure was then further tested and optimized on the simulated data and the real CT data of selected samples with different compositions. The performance of the procedure was quantitatively evaluated in terms of the artifacts’ detection accuracy, the comparison with existing methods, and the ability to preserve spatial resolution. The results show a high efficiency of ring removal and the preservation of the original sample’s structure.

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Monte Carlo Modeling and Design of Photon Energy Attenuation Layers for >10× Quantum Yield Enhancement in Si-Based Hard X-ray Detectors

Instruments ◽

10.3390/instruments5020017 ◽

2021 ◽

Vol 5 (2) ◽

pp. 17

Author(s):

Eldred Lee ◽

Kaitlin M. Anagnost ◽

Zhehui Wang ◽

Michael R. James ◽

Eric R. Fossum ◽

...

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Quantum Yield ◽

Photon Energy ◽

High Efficiency ◽

High Energy ◽

Yield Enhancement ◽

X Ray ◽

Simulation Results ◽

Conversion Efficiencies

High-energy (>20 keV) X-ray photon detection at high quantum yield, high spatial resolution, and short response time has long been an important area of study in physics. Scintillation is a prevalent method but limited in various ways. Directly detecting high-energy X-ray photons has been a challenge to this day, mainly due to low photon-to-photoelectron conversion efficiencies. Commercially available state-of-the-art Si direct detection products such as the Si charge-coupled device (CCD) are inefficient for >10 keV photons. Here, we present Monte Carlo simulation results and analyses to introduce a highly effective yet simple high-energy X-ray detection concept with significantly enhanced photon-to-electron conversion efficiencies composed of two layers: a top high-Z photon energy attenuation layer (PAL) and a bottom Si detector. We use the principle of photon energy down conversion, where high-energy X-ray photon energies are attenuated down to ≤10 keV via inelastic scattering suitable for efficient photoelectric absorption by Si. Our Monte Carlo simulation results demonstrate that a 10–30× increase in quantum yield can be achieved using PbTe PAL on Si, potentially advancing high-resolution, high-efficiency X-ray detection using PAL-enhanced Si CMOS image sensors.

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Holographic x-ray detection: A method for high resolution, high efficiency x-ray detection with differential phase contrast

Applied Physics Letters ◽

10.1063/5.0053357 ◽

2021 ◽

Vol 118 (26) ◽

pp. 261105

Author(s):

G. K. Herring ◽

L. Hesselink

Keyword(s):

High Resolution ◽

Phase Contrast ◽

High Efficiency ◽

X Ray ◽

Differential Phase ◽

Differential Phase Contrast

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Combination of Dual-Energy X-ray Transmission and Variable Gas-Ejection for the In-Line Automatic Sorting of Many Types of Scrap in One Measurement

Applied Sciences ◽

10.3390/app11104349 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4349

Author(s):

Tianzhong Xiong ◽

Wenhua Ye ◽

Xiang Xu

Keyword(s):

High Efficiency ◽

Nearest Neighbor ◽

High Energy ◽

Dual Energy ◽

Center Of Gravity ◽

Low Energy ◽

Identification Accuracy ◽

Flow Process ◽

X Ray ◽

Automatic Sorting

As an important part of pretreatment before recycling, sorting has a great impact on the quality, efficiency, cost and difficulty of recycling. In this paper, dual-energy X-ray transmission (DE-XRT) combined with variable gas-ejection is used to improve the quality and efficiency of in-line automatic sorting of waste non-ferrous metals. A method was proposed to judge the sorting ability, identify the types, and calculate the mass and center-of-gravity coordinates according to the shading of low-energy, the line scan direction coordinate and transparency natural logarithm ratio of low energy to high energy (R_value). The material identification was satisfied by the nearest neighbor algorithm of effective points in the material range to the R_value calibration surface. The flow-process of identification was also presented. Based on the thickness of the calibration surface, the material mass and center-of-gravity coordinates were calculated. The feasibility of controlling material falling points by variable gas-ejection was analyzed. The experimental verification of self-made materials showed that identification accuracy by count basis was 85%, mass and center-of-gravity coordinates calculation errors were both below 5%. The method proposed features high accuracy, high efficiency, and low operation cost and is of great application value even to other solid waste sorting, such as plastics, glass and ceramics.

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