scholarly journals Pixelated transmission-mode diamond X-ray detector

2015 ◽  
Vol 22 (6) ◽  
pp. 1396-1402 ◽  
Author(s):  
Tianyi Zhou ◽  
Wenxiang Ding ◽  
Mengjia Gaowei ◽  
Gianluigi De Geronimo ◽  
Jen Bohon ◽  
...  
Keyword(s):  
Single Channel ◽  
Sampling Rate ◽  
Incident Beam ◽  
Chemical Vapor ◽  
High Energy ◽  
Transmission Mode ◽  
Beam Position ◽  
Synchrotron Source ◽  
X Ray ◽  
Single Crystal Diamond

Fabrication and testing of a prototype transmission-mode pixelated diamond X-ray detector (pitch size 60–100 µm), designed to simultaneously measure the flux, position and morphology of an X-ray beam in real time, are described. The pixel density is achieved by lithographically patterning vertical stripes on the front and horizontal stripes on the back of an electronic-grade chemical vapor deposition single-crystal diamond. The bias is rotated through the back horizontal stripes and the current is read out on the front vertical stripes at a rate of ∼1 kHz, which leads to an image sampling rate of ∼30 Hz. This novel signal readout scheme was tested at beamline X28C at the National Synchrotron Light Source (white beam, 5–15 keV) and at beamline G3 at the Cornell High Energy Synchrotron Source (monochromatic beam, 11.3 keV) with incident beam flux ranges from 1.8 × 10−2to 90 W mm−2. Test results show that the novel detector provides precise beam position (positional noise within 1%) and morphology information (error within 2%), with an additional software-controlled single channel mode providing accurate flux measurement (fluctuation within 1%).

Confocal X-ray Fluorescence (XRF) Microscopy: A New Technique for the Nondestructive Compositional Depth Profiling of Paintings

2004 ◽  
Vol 852 ◽  
Author(s):  
Arthur R. Woll ◽  
Donald H. Bilderback ◽  
Sol Gruner ◽  
Ning Gao ◽  
Rong Huang ◽  
...  
Keyword(s):  
Depth Profiling ◽  
Incident Beam ◽  
High Energy ◽  
X Rays ◽  
Oil Painting ◽  
Synchrotron Source ◽  
X Ray ◽  
Glass Slides ◽  
A New Technique ◽  
Paint Films

ABSTRACTA confocal x-ray fluorescence microscope was built at the Cornell High Energy Synchrotron Source (CHESS) to determine the composition of buried paint layers that range from 10–80 μm thick in paintings. The microscope consists of a borosilicate monocapillary optic to focus the incident beam and a borosilicate polycapillary lens to collect the fluorescent x-rays. The overlap of the two focal regions is several tens of microns in extent, and defines the active, or confocal, volume of the microscope. The capabilities of the technique were tested using acrylic paint films with distinct layers brushed onto glass slides and a twentieth century oil painting on canvas. The position and thickness of individual layers were extracted from their fluorescence profiles by fitting to a simple, semi-empirical model.

Side-bounce beamlines using single-reflection diamond monochromators at Cornell High Energy Synchrotron Source

2021 ◽  
Vol 28 (2) ◽  
pp. 429-438
Author(s):  
Stanislav Stoupin ◽  
Thomas Krawczyk ◽  
David Sagan ◽  
Alexander Temnykh ◽  
Louisa Smieska ◽  
...  
Keyword(s):  
Chemical Vapor ◽  
Functional Materials ◽  
Soft Materials ◽  
High Energy ◽  
Bragg Angle ◽  
Chemical Vapor Deposition Method ◽  
X Rays ◽  
Time Resolved ◽  
Synchrotron Source ◽  
X Ray

The design and implementation of new beamlines featuring side-bounce (single-reflection) diamond monochromators at Cornell High Energy Synchrotron Source (CHESS) are described. Undulator radiation is monochromated using an interchangeable set of diamond crystal plates reflecting radiation in the horizontal (synchrotron) plane, where each crystal plate is set to one of the low-index Bragg reflections (111, 220, 311 and 400) in either Bragg or Laue reflection geometries. At the nominal Bragg angle of 18° these reflections deliver monochromated X-rays with photon energies of 9.7, 15.9, 18.65 and 22.5 keV, respectively. An X-ray mirror downstream of the diamond monochromator is used for rejection of higher radiation harmonics and for initial focusing of the monochromated beam. The characteristics of the X-ray beam entering the experimental station were measured experimentally and compared with the results of simulations. A reasonable agreement is demonstrated. It is shown that the use of selected high-dislocation-density `mosaic' diamond single-crystal plates produced using the chemical vapor deposition method yields a few-fold enhancement in the flux density of the monochromated beam in comparison with that delivered by perfect crystals under the same conditions. At present, the Functional Materials Beamline at CHESS, which is used for time-resolved in situ characterization of soft materials during processing, has been outfitted with the described setup.

Ultra-thin optical grade scCVD diamond as X-ray beam position monitor

2014 ◽  
Vol 21 (6) ◽  
pp. 1217-1223 ◽  
Author(s):  
Kewin Desjardins ◽  
Michal Pomorski ◽  
John Morse
Keyword(s):  
Plasma Etching ◽  
Collection Efficiency ◽  
Sampling Rate ◽  
Central Area ◽  
Chemical Vapor ◽  
Beam Position Monitor ◽  
Beam Position ◽  
Charge Collection Efficiency ◽  
X Ray ◽  
Diamond Plate

Results of measurements made at the SIRIUS beamline of the SOLEIL synchrotron for a new X-ray beam position monitor based on a super-thin single crystal of diamond grown by chemical vapor deposition (CVD) are presented. This detector is a quadrant electrode design processed on a 3 µm-thick membrane obtained by argon–oxygen plasma etching the central area of a CVD-grown diamond plate of 60 µm thickness. The membrane transmits more than 50% of the incident 1.3 keV energy X-ray beam. The diamond plate was of moderate purity (∼1 p.p.m. nitrogen), but the X-ray beam induced current (XBIC) measurements nevertheless showed a photo-charge collection efficiency approaching 100% for an electric field of 2 V µm−1, corresponding to an applied bias voltage of only 6 V. XBIC mapping of the membrane showed an inhomogeneity of more than 10% across the membrane, corresponding to the measured variation in the thickness of the diamond plate before the plasma etching process. The measured XBIC signal-to-dark-current ratio of the device was greater than 105, and the X-ray beam position resolution of the device was better than a micrometer for a 1 kHz sampling rate.

scholarly journals Improved Phebus laser performances required for precision laser–target experiments

1998 ◽  
Vol 16 (2) ◽  
pp. 253-265 ◽  
Author(s):  
G. Thiell ◽  
R. Bailly-Salins ◽  
J.L. Bruneau ◽  
G. Coulaud ◽  
P. Estraillier ◽  
...  
Keyword(s):  
Laser Energy ◽  
Incident Beam ◽  
High Energy ◽  
Target Chamber ◽  
Laser Target ◽  
Time Resolved ◽  
X Ray ◽  
Target Experiment ◽  
Pointing Precision ◽  
Energy Shots

The Precision Phebus program, started in 1993, emphasizes a series of laser and target experiment objectives on the two-beam Phebus Nd-phosphate glass laser. Recently, three major objectives that are also very important issues for megajoule-class lasers have been met: First, the balance of the incident beam-to-beam 3ω power is shown to be in the range from 5 to 12% for 3-ns, 3ω-shaped pulses of reproducible high-energy shots; second, the smoothing uniformity of the laser energy deposited on the target, that is, the contrast of the spatial beam modulations, can be kept lower than 5%; and, finally, the tight control of the beam targeting leads to a pointing precision of less than 10 μrd on the target at the target chamber center (TCC) and of 80 μrd on X-ray sources located up to 3 cm from the TCC to improve the space- and time-resolved X-ray shadowgraphy techniques performed for target physics experiments such as implosion and hydrodynamical instability studies.

scholarly journals X-Ray Beam Position Monitor Based on a Single Crystal Diamond Performing Bunch by Bunch Detection

2013 ◽  
Vol 425 (21) ◽  
pp. 212001 ◽  
Author(s):  
M Di Fraia ◽  
M Antonelli ◽  
A Tallaire ◽  
J Achard ◽  
S Carrato ◽  
...  
Keyword(s):  
Single Crystal ◽  
Beam Position Monitor ◽  
Beam Position ◽  
X Ray ◽  
Single Crystal Diamond

Time-Resolved X-Ray Studies During Pulsed-Laser Irradiation of Ge

1984 ◽  
Vol 35 ◽  
Author(s):  
J.Z. Tischler ◽  
B.C. Larson ◽  
D.M. Mills
Keyword(s):  
Melting Point ◽  
Laser Irradiation ◽  
Pulsed Laser ◽  
Laser Pulses ◽  
High Energy ◽  
Measured Temperature ◽  
Time Resolved ◽  
Synchrotron Source ◽  
X Ray ◽  
Pulsed Laser Irradiation

ABSTRACTSynchrotron x-ray pulses from the Cornell High Energy Synchrotron Source (CHESS) have been used to carry out nanosecond resolution measurements of the temperature distrubutions in Ge during UV pulsed-laser irradiation. KrF (249 nm) laser pulses of 25 ns FWHM with an energy density of 0.6 J/cm2 were used. The temperatures were determined from x-ray Bragg profile measurements of thermal expansion induced strain on <111> oriented Ge. The data indicate the presence of a liquid-solid interface near the melting point, and large (1500-4500°C/pm) temperature gradients in the solid; these Ge results are analagous to previous ones for Si. The measured temperature distributions are compared with those obtained from heat flow calculations, and the overheating and undercooling of the interface relative to the equilibrium melting point are discussed.

scholarly journals In Situ Stress Tensor Determination during Phase Transformation of a Metal Matrix Composite by High-Energy X-ray Diffraction

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1415 ◽  
Author(s):  
Guillaume Geandier ◽  
Lilian Vautrot ◽  
Benoît Denand ◽  
Sabine Denis
Keyword(s):  
Phase Transformation ◽  
Stress Tensor ◽  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Metal Matrix ◽  
High Energy ◽  
X Ray Diffraction ◽  
Synchrotron Source ◽  
X Ray

In situ high-energy X-ray diffraction using a synchrotron source performed on a steel metal matrix composite reinforced by TiC allows the evolutions of internal stresses during cooling to be followed thanks to the development of a new original experimental device (a transportable radiation furnace with controlled rotation of the specimen). Using the device on a high-energy beamline during in situ thermal treatment, we were able to extract the evolution of the stress tensor components in all phases: austenite, TiC, and even during the martensitic phase transformation of the matrix.

scholarly journals Cornell’s Role in Developing Synchrotron Radiation for Mineral Physics

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 514
Author(s):  
William A. Bassett
Keyword(s):  
Perfect Match ◽  
Emission Spectra ◽  
High Energy ◽  
Complex Ions ◽  
Synchrotron Source ◽  
Mineral Physics ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Diamond Anvil ◽  
Deep Focus

The newly invented diamond anvil cell (DAC) in 1960, and the newly constructed Cornell High Energy Synchrotron Source (CHESS) in 1979 were a perfect match, as CHESS could provide such an intense X-ray beam with such extraordinary properties that a whole new approach to mineral physics research became possible. The very high intensity of the X-ray beam from CHESS made it possible to make real-time observations of crystal structures during phase transitions for the first time. For instance, the olivine-spinel transition, important for understanding deep focus earthquakes can be shown to take place first by the displacive shift of oxygen layers supporting shear stress as most likely earthquake trigger followed by the diffusion of the cations to their positions in the spinel structure. X-ray emission spectra of high-pressure, high-temperature samples also made it possible to determine phase compositions, as well as the structures of complex ions in solution.

Characterization of X-ray gas attenuator plasmas by optical emission and tunable laser absorption spectroscopies

2017 ◽  
Vol 24 (6) ◽  
pp. 1195-1208 ◽  
Author(s):  
Álvaro Martín Ortega ◽  
Ana Lacoste ◽  
Stéphane Béchu ◽  
Alexandre Bès ◽  
Nader Sadeghi
Keyword(s):  
Incident Beam ◽  
Tunable Laser ◽  
Optical Emission ◽  
High Energy ◽  
Beam Power ◽  
Beam Path ◽  
Optical Elements ◽  
X Ray ◽  
Laser Absorption ◽  
X Ray Absorption

X-ray gas attenuators are used in high-energy synchrotron beamlines as high-pass filters to reduce the incident power on downstream optical elements. The absorption of the X-ray beam ionizes and heats up the gas, creating plasma around the beam path and hence temperature and density gradients between the center and the walls of the attenuator vessel. The objective of this work is to demonstrate experimentally the generation of plasma by the X-ray beam and to investigate its spatial distribution by measuring some of its parameters, simultaneously with the X-ray power absorption. The gases used in this study were argon and krypton between 13 and 530 mbar. The distribution of the 2pexcited states of both gases was measured using optical emission spectroscopy, and the density of argon metastable atoms in the 1s5state was deduced using tunable laser absorption spectroscopy. The amount of power absorbed was measured using calorimetry and X-ray transmission. The results showed a plasma confined around the X-ray beam path, its size determined mainly by the spatial dimensions of the X-ray beam and not by the absorbed power or the gas pressure. In addition, the X-ray absorption showed a hot central region at a temperature varying between 400 and 1100 K, depending on the incident beam power and on the gas used. The results show that the plasma generated by the X-ray beam plays an essential role in the X-ray absorption. Therefore, plasma processes must be taken into account in the design and modeling of gas attenuators.

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