scholarly journals Investigation on radiation generated by sub-GeV electrons in ultrashort silicon and germanium bent crystals

2021 ◽  
Vol 81 (4) ◽  
Author(s):  
L. Bandiera ◽  
A. Sytov ◽  
D. De Salvador ◽  
A. Mazzolari ◽  
E. Bagli ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Beam Direction ◽  
X Ray ◽  
Radiation Spectra ◽  
Radiation Sources ◽  
Angular Acceptance ◽  
Volume Reflection ◽  
Silicon And Germanium ◽  
Bent Crystals ◽  
First Time

AbstractWe report on the measurements of the spectra of gamma radiation generated by 855 MeV electrons in bent silicon and germanium crystals at MAMI (MAinzer MIkrotron). The crystals were 15 $$\upmu \text {m}$$ μ m thick along the beam direction to ensure high deflection efficiency. Their (111) crystalline planes were bent by means of a piezo-actuated mechanical holder, which allowed to remotely change the crystal curvature. In such a way it was possible to investigate the radiation emitted under planar channeling and volume reflection as a function of the curvature of the crystalline planes. We showed that, using volume reflection, intense gamma radiation can be produced – with intensity comparable to that obtained in channeling but with higher angular acceptance. We studied the trade-off between radiation intensity and angular acceptance at different values of the crystal curvature. The measurements of radiation spectra have been carried out for the first time in bent germanium crystals. In particular, the intensity of radiation in the germanium crystal is higher than in the silicon one due to the higher atomic number, which is important for the development of the X-ray and gamma radiation sources based on higher-Z deformed crystals, such as crystalline undulators.

scholarly journals Shadow monochromatic backlighting: Large-field high resolution X-ray shadowgraphy with improved spectral tunability

2001 ◽  
Vol 19 (2) ◽  
pp. 285-293 ◽  
Author(s):  
T.A. PIKUZ ◽  
A. YA. FAENOV ◽  
M. FRAENKEL ◽  
A. ZIGLER ◽  
F. FLORA ◽  
...  
Keyword(s):  
High Resolution ◽  
High Spatial Resolution ◽  
Field Of View ◽  
Large Field ◽  
X Ray ◽  
Traditional Scheme ◽  
Wide Range ◽  
Wide Wavelength Range ◽  
Bent Crystals ◽  
First Time

The shadow monochromatic backlighting (SMB) scheme, a modification of the well-known soft X-ray monochromatic backlighting scheme, is proposed. It is based on a spherical crystal as the dispersive element and extends the traditional scheme by allowing one to work with a wide range of Bragg angles and thus in a wide spectral range. The advantages of the new scheme are demonstrated experimentally and supported numerically by ray-tracing simulations. In the experiments, the X-ray backlighter source is a laser-produced plasma, created by the interaction of an ultrashort pulse, Ti:Sapphire laser (120 fs, 3–5 mJ, 1016 W/cm2 on target) or a short wavelength XeCl laser (10 ns, 1–2 J, 1013 W/cm2 on target) with various solid targets (Dy, Ni + Cr, BaF2). In both experiments, the X-ray sources are well localized spatially (∼20 μm) and are spectrally tunable in a relatively wide wavelength range (λ = 8–15 Å). High quality monochromatic (δλ/λ ∼ 10−5–10−3) images with high spatial resolution (up to ∼4 μm) over a large field of view (a few square millimeters) were obtained. Utilization of spherically bent crystals to obtain high-resolution, large field, monochromatic images in a wide range of Bragg angles (35° < Θ < 90°) is demonstrated for the first time.

scholarly journals The Dosimetric Parameters Investigation of the Pulsed X-ray and Gamma Radiation Sources

2016 ◽  
Vol 671 ◽  
pp. 012051 ◽  
Author(s):  
S G Stuchebrov ◽  
I A Miloichikova ◽  
X O Shilova
Keyword(s):  
Gamma Radiation ◽  
X Ray ◽  
Radiation Sources

Cyclic topology effects on the morphology of biocompatible and environment-friendly poly(ε-caprolactone) under nanoscale film confinement

2020 ◽  
Vol 11 (28) ◽  
pp. 4630-4638 ◽  
Author(s):  
Li Xiang ◽  
Wonyeong Ryu ◽  
Jehan Kim ◽  
Moonhor Ree
Keyword(s):  
Synchrotron Radiation ◽  
Grazing Incidence ◽  
Film Morphology ◽  
Environment Friendly ◽  
X Ray ◽  
X Ray Scattering ◽  
Radiation Sources ◽  
First Time ◽  
Ray Scattering

Quantitative grazing incidence X-ray scattering analysis combined with X-ray reflectivity using synchrotron radiation sources was explored for the first time cyclic topology effects on the nanoscale film morphology of poly(ε-caprolactone).

scholarly journals Degradation of 4-Chlorophenol by Gamma Radiation of 137Cs and X-rays

2019 ◽  
Vol 54 (3) ◽  
Author(s):  
Julio César González-Juárez ◽  
Jaime Jiménez-Becerril ◽  
Jesús Cejudo-Álvarez
Keyword(s):  
Energy Transfer ◽  
Gamma Radiation ◽  
Crystalline Structure ◽  
Linear Energy Transfer ◽  
The Other ◽  
X Rays ◽  
137Cs Source ◽  
X Ray ◽  
Radiolytic Degradation ◽  
Radiation Sources

This paper presents results of radiolytic degradation of 4-chlorophenol in the presence of TiO2, Al2O3, y SiO2, using different radiation sources than 60Co, which is so common in this type of experiment. The radiation sources used were X-rays with energy of 100 keV and radiation from 137Cs (662 keV). After irradiation with a dose of 50 cGy X-ray and TiO2 obtained a degradation of about 5%, no degradation was obtained with 137Cs source and other oxides. This may be due to the fact that X-rays have a linear energy transfer (LET) greater value, and in the case of TiO2 present a crystalline structure, whereas the other two oxides are amorphous. Both characteristics result in better formation of a reactive species that allows the degradation of the compound.

scholarly journals Angular asymmetry of the nuclear interaction probability of high energy particles in short bent crystals

2020 ◽  
Vol 80 (1) ◽  
Author(s):  
W. Scandale ◽  
F. Cerutti ◽  
L. S. Esposito ◽  
M. Garattini ◽  
S. Gilardoni ◽  
...  
Keyword(s):  
Silicon Crystal ◽  
Nuclear Interaction ◽  
High Energy ◽  
Planar Channeling ◽  
The North ◽  
Volume Reflection ◽  
Bent Crystals ◽  
First Time ◽  
High Energy Particles ◽  
Hadron Beam

AbstractThe rate of inelastic nuclear interactions in a short bent silicon crystal was precisely measured for the first time using a 180 GeV/c positive hadron beam produced in the North Experimental Area of the CERN SPS. An angular asymmetry dependence on the crystal orientation in the vicinity of the planar channeling minimum has been observed. For the inspected crystal, this probability is about $$\sim 20\%$$∼20% larger than in the amorphous case because of the atomic density increase along the particle trajectories in the angular range of volume reflection, whose dimension is determined by the crystal bending angle. Instead, for the opposite angular orientation with respect to the planar channeling, there is a smaller probability excess of $$\sim 4\%$$∼4%.

Gamma radiation sources with57CO for x-ray fluorescence analysis

Atomic Energy ◽  
1992 ◽  
Vol 72 (4) ◽  
pp. 366-368
Author(s):  
A. I. Leonov ◽  
V. G. Meshcheryakov ◽  
G. V. Tyamin
Keyword(s):  
Gamma Radiation ◽  
Fluorescence Analysis ◽  
X Ray ◽  
Radiation Sources

scholarly journals Correct interpretation of diffraction properties of quartz crystals for X-ray optics applications

2018 ◽  
Vol 51 (1) ◽  
pp. 140-147 ◽  
Author(s):  
Xian-Rong Huang ◽  
Thomas Gog ◽  
Jungho Kim ◽  
Elina Kasman ◽  
Ayman H. Said ◽  
...  
Keyword(s):  
Rotational Symmetry ◽  
Bragg Angle ◽  
Correct Interpretation ◽  
Ray Optics ◽  
Quartz Crystals ◽  
X Ray ◽  
Angular Acceptance ◽  
Silicon And Germanium ◽  
Laue Method

Quartz has hundreds of strong Bragg reflections that may offer a great number of choices for making fixed-angle X-ray analyzers and polarizers at virtually any hard X-ray energies with selectable resolution. However, quartz crystals, unlike silicon and germanium, are chiral and may thus appear in two different forms of handedness that are mirror images. Furthermore, because of the threefold rotational symmetry along thecaxis, the {h1h2h3L} and {h2h1h3L} Bragg reflections may have quite different Darwin bandwidth, reflectivity and angular acceptance, although they have the same Bragg angle. The design of X-ray optics from quartz crystals therefore requires unambiguous determination of the orientation, handedness and polarity of the crystals. The Laue method and single-axis diffraction technique can provide such information, but the variety of conventions used in the literature to describe quartz structures has caused widespread confusion. The current studies give detailed guidelines for design and fabrication of quartz X-ray optics, with special emphasis on the correct interpretation of Laue patterns in terms of the crystallography and diffraction properties of quartz. Meanwhile, the quartz crystals examined were confirmed by X-ray topography to have acceptably low densities of dislocations and other defects, which is the foundation for developing high-resolution quartz-based X-ray optics.

Comparison of Lead, Copper and Aluminium as Gamma Radiation Shielding Material through Experimental Measurements and Simulation Using MCNP Version 4c

2018 ◽  
Vol 9 (08) ◽  
pp. 20193-20206 ◽  
Author(s):  
Md. Akhlak Bin Aziz ◽  
Md. Faisal Rahman ◽  
Md. Mahidul Haque Prodhan
Keyword(s):  
Gamma Radiation ◽  
Sodium Iodide ◽  
Experimental Approach ◽  
Radiation Shielding ◽  
Test Material ◽  
Simulation Techniques ◽  
Radiation Sources ◽  
Simulation Monte Carlo ◽  
Shielding Material ◽  
Code Version

The paper compares  Lead, Copper and Aluminium as gamma radiation shielding material using both experimental and simulation techniques. Cs- 137 (662KeV), Na-22 (511KeV) and Na- 22(1274KeV) were used as gamma radiation sources and a sodium iodide (NaI) detector was used to detect the radiation. Variations were noted for detected gamma count rates by changing shielding material thickness. In the experimental approach, thickness was varied by placing sheets of a particular test material one by one. For simulation, Monte Carlo n- Particle (MCNP) code version 4c was used and the geometry of the whole experimental setup was plotted in it. The results were then compared for each test material and it was found that lead is the best shielding material for gamma radiation followed by copper and aluminium.

Study of Heptamethine Iodide and Heptamethine PF6 Solutions in Different Solvents for the Measurement of Low Doses of X-Ray & Gamma Radiation

2016 ◽  
Vol 5 (4) ◽  
pp. 308-317
Author(s):  
Hagos Tesfay ◽  
Erika S. Bronze-Uhle ◽  
Augusto Batagin-Neto ◽  
Anna C. Véron ◽  
Thomas Geiger ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Low Doses ◽  
X Ray

Diphosphinoazine Rhodium(I) and Iridium(I) Complexes

2006 ◽  
Vol 71 (2) ◽  
pp. 197-206 ◽  
Author(s):  
Martin Pošta ◽  
Jan Čermák ◽  
Pavel Vojtíšek ◽  
Ivana Císařová
Keyword(s):  
Rhodium Complexes ◽  
Iridium Complexes ◽  
X Ray ◽  
First Time

The first rhodium complexes of diphosphinoazines [{RhCl(1,2-η:5,6-η-CH=CHCH2CH2CH=CHCH2CH2)}2 {μ-R2PCH2C(But)=NN=C(But)CH2PR2] (R = Ph, Cy, Pri) were prepared by cleavage of the bridge in chloro(cycloocta-1,5-diene)rhodium(I) dimer, the analogous iridium(I) complexes were also prepared for the first time. The X-ray structures of isostructural rhodium and iridium complexes with bis(dicyclohexylphosphino)pinacoloneazine were determined. Diphosphinoazine ligands in the complexes remained in (Z,Z) configuration bridging two RhCl(C8H12) units.

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