Design of a prototype split-and-delay unit for XFEL pulses, and their evaluation by synchrotron radiation X-rays

2017 ◽  
Vol 24 (1) ◽  
pp. 95-102 ◽  
Author(s):  
Jun'ya Sakamoto ◽  
Kenji Ohwada ◽  
Masahiko Ishino ◽  
Jun'ichiro Mizuki ◽  
Masami Ando ◽  
...  
Keyword(s):  
Delay Time ◽  
Bragg Reflection ◽  
Silicon Crystal ◽  
X Rays ◽  
Charge Coupled Device ◽  
X Ray ◽  
Delay Unit ◽  
Delay Times ◽  
Crystal Alignment ◽  
Longitudinal Coherence

A prototype split-and-delay unit (SDU) for X-ray free-electron laser (XFEL) pulses is proposed based on the Graeff–Bonse four-Bragg-reflection interferometer by installing 12.5° slopes. The SDU can continuously provide a delay time from approximately −20 to 40 ps with a resolution of less than 26 fs. Because the SDU was constructed from a monolithic silicon crystal, alignment is straightforward. The obtained thoroughputs of the SDU reached 0.7% at 7.46 keV and 0.02% at 14.92 keV. The tunability of the delay time using the proposed SDU was demonstrated by finding the interference effects of the split X-rays, and the time resolution of the proposed SDU was evaluated using the width of the interference pattern recorded on the X-ray charge-coupled device camera by changing the energy, i.e. longitudinal coherence length, of the incident X-rays. It is expected that the proposed SDU will be applicable to XFEL experiments using delay times from tens of femtoseconds to tens of picoseconds, e.g. intensity correlation measurements.

Investigation of the phase shift in X-ray forward diffraction using an X-ray interferometer

1998 ◽  
Vol 5 (3) ◽  
pp. 967-968 ◽  
Author(s):  
Keiichi Hirano ◽  
Atsushi Momose
Keyword(s):  
Phase Shift ◽  
Silicon Crystal ◽  
Dynamical Theory ◽  
Perfect Crystal ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bragg Geometry

The phase shift of forward-diffracted X-rays by a perfect crystal is discussed on the basis of the dynamical theory of X-ray diffraction. By means of a triple Laue-case X-ray interferometer, the phase shift of forward-diffracted X-rays by a silicon crystal in the Bragg geometry was investigated.

Diamond channel-cut crystals for high-heat-load beam-multiplexing narrow-band X-ray monochromators

2021 ◽  
Vol 28 (6) ◽  
Author(s):  
Yuri Shvyd'ko ◽  
Sergey Terentyev ◽  
Vladimir Blank ◽  
Tomasz Kolodziej
Keyword(s):  
Heat Load ◽  
Narrow Band ◽  
Bragg Reflection ◽  
High Heat ◽  
High Repetition Rate ◽  
X Rays ◽  
Ray Optics ◽  
X Ray ◽  
Load Beam ◽  
High Heat Load

Next-generation high-brilliance X-ray photon sources call for new X-ray optics. Here we demonstrate the possibility of using monolithic diamond channel-cut crystals as high-heat-load beam-multiplexing narrow-band mechanically stable X-ray monochromators with high-power X-ray beams at cutting-edge high-repetition-rate X-ray free-electron laser (XFEL) facilities. The diamond channel-cut crystals fabricated and characterized in these studies are designed as two-bounce Bragg reflection monochromators directing 14.4 or 12.4 keV X-rays within a 15 meV bandwidth to 57Fe or 45Sc nuclear resonant scattering experiments, respectively. The crystal design allows out-of-band X-rays transmitted with minimal losses to alternative simultaneous experiments. Only ≲2% of the incident ∼100 W X-ray beam is absorbed in the 50 µm-thick first diamond crystal reflector, ensuring that the monochromator crystal is highly stable. Other X-ray optics applications of diamond channel-cut crystals are anticipated.

scholarly journals Experimentally obtained and computer-simulated X-ray non-coplanar 18-beam pinhole topographs for a silicon crystal

2019 ◽  
Vol 75 (3) ◽  
pp. 483-488 ◽  
Author(s):  
Kouhei Okitsu ◽  
Yasuhiko Imai ◽  
Yoshitaka Yoda
Keyword(s):  
Silicon Crystal ◽  
Dynamical Theory ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Good Agreement

Non-coplanar 18-beam X-ray pinhole topographs for a silicon crystal were computer simulated by fast Fourier transforming the X-ray rocking amplitudes that were obtained by solving the n-beam (n = 18) Ewald–Laue dynamical theory (E-L&FFT method). They were in good agreement with the experimentally obtained images captured using synchrotron X-rays. From this result and further consideration based on it, it has been clarified that the X-ray diffraction intensities when n X-ray waves are simultaneously strong in the crystal can be computed for any n by using the E-L&FFT method.

Measurements of Soft and Ultrasoft X-Rays with Total Reflection Monochromator

1986 ◽  
Vol 30 ◽  
pp. 213-223
Author(s):  
Tomoya Arai
Keyword(s):  
Gas Flow ◽  
Bragg Reflection ◽  
Optical Resolution ◽  
Fluorescence Analysis ◽  
Total Reflection ◽  
X Rays ◽  
Light Elements ◽  
Lower Intensity ◽  
Measured Intensity ◽  
X Ray

The development of X-ray spectrographic analysis of light elements, which are O, C and B, has bee n performed for many applications using an end-window type X-ray tube with Rh-target and thin Be-window, wavelength dispersing devices, which are synthetic multilayers or total reflection mirror (with a specific filter) and a gas flow proportional counter with a thin film window. In Fig. 1 factors related to the intensity measurements in X-ray fluorescence analysis are shown. The excitation efficiency in the soft and ultrasoft X-ray region is very low because of the lower intensity of primary X-rays and low fluorescence yield of light elements. Instead of the wavelength dispersive method of Bragg reflection, having high resolution and low reflectivity, monochromatization combining total reflection by a selected mirror and an appropriate filter offered an alternate approach in order to increase measured intensity with reasonable optical resolution. Synthetic multilayers which have higher resolution and lower intensity compared with the performance of the mirror method have become popular for the detection of soft and ultrasoft X-ray region.

GENERATION OF X-RAYS WITH A HIGH DEGREE OF LONGITUDINAL COHERENCE

2007 ◽  
Vol 21 (03n04) ◽  
pp. 513-518
Author(s):  
ROBERT ROSSMANITH
Keyword(s):  
Synchrotron Radiation ◽  
Storage Rings ◽  
Light Sources ◽  
X Rays ◽  
X Ray ◽  
Electron Accelerators ◽  
Longitudinal Coherence ◽  
High Degree

Synchrotron radiation produced either in storage rings or SASE-FELs is longitudinally incoherent. In this paper a way to produce short longitudinally coherent X-ray pulses is discussed. In addition it is investigated if these sources can be modified to use them as light sources for vacuum electron accelerators.

Limits of the X-Ray Collimation by One Asymmetrical Bragg Reflection

1982 ◽  
Vol 37 (6) ◽  
pp. 519-523 ◽  
Author(s):  
◽  
H. R. Höche ◽  
J. Nieber
Keyword(s):  
Bragg Reflection ◽  
Dynamical Theory ◽  
X Rays ◽  
Optimum Conditions ◽  
X Ray Diffraction ◽  
X Ray

Abstract In connection with the production of highly collimated X-rays the study of extremely asymmetrical Bragg reflections became of interest. In this paper the so-called extended dynamical theory of X-ray diffraction will be tested experimentally. As a result of this investigations the optimum conditions for X-ray collimation by means of one asymmetrical Bragg reflection are being discussed.

X-Ray Absroption Table for the 2-to-200 Å Region

1969 ◽  
Vol 13 ◽  
pp. 639-665 ◽  
Author(s):  
B. L, Henke and ◽  
R. L. Elgin
Keyword(s):  
Extreme Ultraviolet ◽  
Bragg Reflection ◽  
Pulse Height ◽  
X Rays ◽  
Temperature Plasma ◽  
X Ray ◽  
Langmuir Blodgett ◽  
Intensity Measurements ◽  
Measured Absorption ◽  
Physical And Chemical

Physical and chemical analysis, X-ray astronomy and high temperature plasma diagnostics which utilize the ultrasoft X-radiations hare made evident a strong need for filling the gap in measured absorption coefficient data for the radiations between the conventional X-rays and the extreme ultraviolet. More than one hundred new coefficients have been measured in this laboratory on the gas state, atomic or molecular, containing He, C, N, 0, F, Ne, S, Cl, Ar, Kr and Xe using eleven fluorescent, characteristic wavelengths Al-Kα (8.34 A) through Be-K (113.8 A). The radiations were isolated by Bragg reflection from multilayer analyzers of the Langmuir-Blodgett type and by pulse height discriminating proportional counter intensity measurements.

scholarly journals X-rays only when you want them: optimized pump–probe experiments using pseudo-single-bunch operation

2015 ◽  
Vol 22 (3) ◽  
pp. 729-735 ◽  
Author(s):  
M. P. Hertlein ◽  
A. Scholl ◽  
A. A. Cordones ◽  
J. H. Lee ◽  
K. Engelhorn ◽  
...  
Keyword(s):  
Laser Excitation ◽  
Ccd Camera ◽  
Single Shot ◽  
X Rays ◽  
Time Resolved ◽  
Pump Probe ◽  
Charge Coupled Device ◽  
X Ray ◽  
X Ray Absorption ◽  
Sample Damage

Laser pump–X-ray probe experiments require control over the X-ray pulse pattern and timing. Here, the first use of pseudo-single-bunch mode at the Advanced Light Source in picosecond time-resolved X-ray absorption experiments on solutions and solids is reported. In this mode the X-ray repetition rate is fully adjustable from single shot to 500 kHz, allowing it to be matched to typical laser excitation pulse rates. Suppressing undesired X-ray pulses considerably reduces detector noise and improves signal to noise in time-resolved experiments. In addition, dose-induced sample damage is considerably reduced, easing experimental setup and allowing the investigation of less robust samples. Single-shot X-ray exposures of a streak camera detector using a conventional non-gated charge-coupled device (CCD) camera are also demonstrated.

Effects of source size and wavefront propagation on the energy resolution of a bent-crystal polychromator

2010 ◽  
Vol 1 (MEDSI-6) ◽  
Author(s):  
J. P. Sutter ◽  
M. Amboage ◽  
S. Hayama ◽  
S. Díaz-Moreno
Keyword(s):  
Energy Resolution ◽  
Silicon Crystal ◽  
X Rays ◽  
Pixel Size ◽  
X Ray ◽  
Bent Crystal ◽  
Full Wave ◽  
Instrumental Resolution ◽  
Optical Treatment ◽  
X Ray Absorption

Polychromators, or elliptically bent diffracting crystals that focus a broad-bandwidth X-ray beam onto a sample, have become a common device at synchrotron beamlines specializing in X-ray absorption spectroscopy (XAS) because they allow a full absorption spectrum to be collected in one shot. Such a device is being planned for the XAS beamline I20 of the Diamond Light Source. A bent silicon crystal diffracting 7 keV X-rays with the (1 1 1) reflection is taken as a model for the simulations of this report. Instrumental resolution is determined by the demagnification of the source, the spread of the diffracted beam during propagation and the pixel size of the position-sensitive detector placed behind the sample. The first is calculated by geometrical optics. The second is calculated by a full wave-optical treatment, which includes Takagi–Taupin integration to find the diffracted amplitude at the crystal's surface and Huygens–Fresnel propagation of the diffracted wave to the sample or detector. This sets the polychromator's intrinsic energy resolution. The pixel size of the detector is then added to find the total instrumental resolution at various sample–detector distances.

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