On symmetric X-ray beam splitting with high efficiency by use of reflection gratings with rectangular profile in the extreme off-plane configuration

ABSTRACT:As dispersing elements, grazing incidence reflection gratings offer the unique combination of high dispersion and wide spectral coverage at high efficiency. They can therefore be coupled with large area, low-resolution mirrors and high quantum efficiency detectors to yield moderate resolution spectroscopy of faint X-ray sources. Various design options are presented and compared, including both objective and convergent-beam configurations and both in-plane and off-plane grating mountings. A specific reflection grating payload design for ESA’s X-Ray Multi-Mirror Mission (XMM) is reviewed in more detail. Predicted performance curves derived from ray trace studies are presented along with preliminary X-ray reflectivity measurements of prototype grating samples.

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Tender X-ray beam splitting with high efficiency by use of multilayer grating based on conical diffraction

Second Target Recognition and Artificial Intelligence Summit Forum ◽

10.1117/12.2552216 ◽

2020 ◽

Author(s):

Liangliang Du ◽

Limin Meng ◽

Ran An ◽

Yan Ye

Keyword(s):

High Efficiency ◽

Beam Splitting ◽

X Ray ◽

Multilayer Grating

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An efficient plane-grating monochromator based on conical diffraction for continuous tuning in the entire soft X-ray range including tender X-rays (2–8 keV)

Journal of Synchrotron Radiation ◽

10.1107/s1600577515021839 ◽

2016 ◽

Vol 23 (1) ◽

pp. 187-195 ◽

Cited By ~ 5

Author(s):

Werner Jark

Keyword(s):

Photon Energy ◽

X Rays ◽

Double Crystal ◽

Efficient Operation ◽

X Ray ◽

Continuous Tuning ◽

Rectangular Profile ◽

Reflection Gratings ◽

Minimum Bandwidth ◽

Grazing Angles

Recently it was verified that the diffraction efficiency of reflection gratings with rectangular profile, when illuminated at grazing angles of incidence with the beam trajectory along the grooves and not perpendicular to them, remains very high for tender X-rays of several keV photon energy. This very efficient operation of a reflection grating in the extreme off-plane orientation,i.e.in conical diffraction, offers the possibility of designing a conical diffraction monochromator scheme that provides efficient continuous photon energy tuning over rather large tuning ranges. For example, the tuning could cover photon energies from below 1000 eV up to 8 keV. The expected transmission of the entire instrument is high as all components are always operated below the critical angle for total reflection. In the simplest version of the instrument a plane grating is preceded by a plane mirror rotating simultaneously with it. The photon energy selection will then be made using the combination of a focusing mirror and exit slit. As is common for grating monochromators for soft X-ray radiation, the minimum spectral bandwidth is source-size-limited, while the bandwidth can be adjusted freely to any larger value. As far as tender X-rays (2–8 keV) are concerned, the minimum bandwidth is at least one and up to two orders of magnitude larger than the bandwidth provided by Si(111) double-crystal monochromators in a collimated beam. Therefore the instrument will provide more flux, which can even be increased at the expense of a bandwidth increase. On the other hand, for softer X-rays with photon energies below 1 keV, competitive relative spectral resolving powers of the order of 10000 are possible.

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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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ESA’s X-Ray Astronomy Mission, XMM

International Astronomical Union Colloquium ◽

10.1017/s0252921100076971 ◽

1990 ◽

Vol 123 ◽

pp. 129-140

Author(s):

B.G. Taylor ◽

A. Peacock

Keyword(s):

Resolving Power ◽

Science Program ◽

Eccentric Orbit ◽

Ccd Cameras ◽

Optical Telescope ◽

X Ray ◽

Medium Resolution ◽

Reflection Gratings ◽

Better Than

AbstractESA’s X-ray Astronomy Mission, XMM, scheduled for launch in 1998, is the second of four cornerstones of ESA’s long term science program Horizon 2000. Covering the range from about 0.1 to 10 keV, it will provide a high throughput of 5000 cm2 at 7 keV with three independant telescopes, and have a spatial resolution better than 30 arcsec. Broadband spectrophotometry is provided by CCD cameras while reflection gratings provide medium resolution spectroscopy (resolving power of about 400) in the range 0.3–3 keV. Long uninterrupted observations will be made from the 24 hr period, highly eccentric orbit, reaching a sensitivity approaching 10−15 erg cm−2 s−1 in one orbit. A 30 cm UV/optical telescope is bore-sighted with the x-ray telescopes to provide simultaneous optical counterparts to the numerous serendipitous X-ray sources which will be detected during every observation.

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